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Rutter MK, Carr MJ, Wright AK, Kanumilli N, Milne N, Jones E, Elton P, Ceriello A, Misra A, Del Prato S, Barron E, Hambling C, Sattar N, Khunti K, Valabhji J, Feldman EL, Ashcroft DM. Indirect effects of the COVID-19 pandemic on diagnosing, monitoring, and prescribing in people with diabetes and strategies for diabetes service recovery internationally. Diabetes Res Clin Pract 2024; 212:111693. [PMID: 38719027 DOI: 10.1016/j.diabres.2024.111693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 05/23/2024]
Abstract
The COVID-19 pandemic has caused major disruptions in clinical services for people with chronic long-term conditions. In this narrative review, we assess the indirect impacts of the COVID-19 pandemic on diabetes services globally and the resulting adverse effects on rates of diagnosing, monitoring, and prescribing in people with type 2 diabetes. We summarise potential practical approaches that could address these issues and improve clinical services and outcomes for people living with diabetes during the recovery phase of the pandemic.
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Affiliation(s)
- Martin K Rutter
- Faculty of Medicine, Biology and Health, University of Manchester, Manchester M13 9PL, United Kingdom; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, NIHR Manchester Biomedical Research Centre, Manchester M13 0JE, United Kingdom.
| | - Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, The University of Manchester, Manchester, United Kingdom; NIHR Greater Manchester Patient Safety Research Collaboration, University of Manchester, Manchester, United Kingdom
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, The University of Manchester, Manchester, United Kingdom
| | - Naresh Kanumilli
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, NIHR Manchester Biomedical Research Centre, Manchester M13 0JE, United Kingdom
| | - Nicola Milne
- Brooklands and Northenden Primary Care Network, Greater Manchester, United Kingdom
| | - Ewan Jones
- Greater Manchester & Eastern Cheshire Strategic Clinical Networks, NHS Greater Manchester Integrated Care, United Kingdom
| | - Peter Elton
- Greater Manchester & Eastern Cheshire Strategic Clinical Networks, NHS Greater Manchester Integrated Care, United Kingdom
| | | | - Anoop Misra
- Fortis C-DOC Centre of Excellence for Diabetes, Metabolic Diseases and Endocrinology, Chirag Enclave, National Diabetes Obesity and Cholesterol Foundation and Diabetes Foundation (India), New Delhi, India
| | - Stefano Del Prato
- Department of Clinical and Experimental Medicine, Section of Metabolic Diseases and Diabetes, University of Pisa, Pisa, Italy
| | - Emma Barron
- NHS England, Wellington House, 122-135 Waterloo Road, London, UK; Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, UK; Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
| | - Clare Hambling
- NHS England, Wellington House, 122-135 Waterloo Road, London, UK; Bridge Street Surgery, Norfolk, United Kingdom
| | - Naveed Sattar
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, United Kingdom
| | - Kamlesh Khunti
- Diabetes Research Centre, University of Leicester, Leicester, United Kingdom
| | - Jonathan Valabhji
- NHS England, Wellington House, 122-135 Waterloo Road, London, UK; Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, UK; Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
| | - Eva L Feldman
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Darren M Ashcroft
- NIHR Greater Manchester Patient Safety Research Collaboration, University of Manchester, Manchester, United Kingdom; Centre for Pharmacoepidemiology and Drug Safety, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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Barron E, Khunti K, Wright AK, Ashcroft DM, Carr MJ, Rutter MK, Valabhji J. Impact of the COVID-19 pandemic on new diagnoses of type 2 diabetes in England. Diabetes Obes Metab 2023; 25:3424-3429. [PMID: 37489091 DOI: 10.1111/dom.15223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/27/2023] [Accepted: 07/06/2023] [Indexed: 07/26/2023]
Affiliation(s)
| | - Kamlesh Khunti
- Diabetes Research Centre, Leicester Diabetes Centre, University of Leicester, Leicester, UK
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- NIHR Greater Manchester Patient Safety Research Collaboration (PSRC), University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre, Manchester, UK
| | - Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- NIHR Greater Manchester Patient Safety Research Collaboration (PSRC), University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre, Manchester, UK
| | - Martin K Rutter
- Manchester Academic Health Science Centre, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Diabetes, Endocrinology and Metabolism Centre, NIHR Manchester Biomedical Research Centre, Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - Jonathan Valabhji
- NHS England, London, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, London, UK
- Division of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
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Choon SE, Wright AK, Griffiths CEM, Wong KW, Tey KE, Lim YT, Chua KY, Ashcroft DM. Incidence and prevalence of generalized pustular psoriasis in multiethnic Johor Bahru, Malaysia: a population-based cohort study using routinely captured electronic health records in the Teleprimary Care (TPC®) clinical information system from 2010 to 2020. Br J Dermatol 2023; 189:410-418. [PMID: 37162007 DOI: 10.1093/bjd/ljad158] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 05/11/2023]
Abstract
BACKGROUND There is limited understanding of the epidemiology of generalized pustular psoriasis (GPP) internationally, with no population-based estimates of GPP in South East Asia. OBJECTIVES To determine the incidence and prevalence of GPP in the Malaysian population and characterize its flares and trigger factors. METHODS We conducted a population-based cohort study using the Teleprimary Care database between January 2010 and December 2020. We identified 230 dermatologist-confirmed GPP cases using International Classification of Diseases, 10th revision, diagnostic codes. Annual prevalence and incidence rates were stratified by age, sex and ethnicity. We compared data regarding flares and trigger factors for patients with GPP who had associated psoriasis vulgaris (PV) with those who did not have associated PV. RESULTS The prevalence of GPP was 198 per million (267 women, 127 men) and incidence was 27.2 per million person-years [95% confidence interval (CI) 22.8-31.6]; 35.3 (28.4-42.2) per million person-years for women and 18.3 (13.1-23.5) per million person-years for men. Rates were higher in Chinese individuals [prevalence 271 per million; incidence 41.6 per million person-years (28.9-54.3)] than in the Malay population [prevalence 186; incidence 24.6 (19.4-29.7)] or the Indian ethnic group [prevalence 179; incidence 25.0 (13.8-36.3)]. Annual prevalence was consistently higher in women than in men and highest among the Chinese population, followed by the Indian and Malay populations. Overall, 67% of patients with GPP had associated PV. The prevalence and incidence of GPP without PV were lower than GPP with PV at 66 vs. 132 per million and 19.3 (95% CI 15.6-23.0) vs. 8.0 (95% CI 5.6-10.3) per million person-years, respectively. The mean age at GPP onset was 42.7 years (SD 18.4). A bimodal trend in the age of GPP onset was observed, with first and second peaks at age 20-29 years and age 50-59 years, respectively. Disease onset was significantly earlier in patients with GPP without PV than in those with PV [mean age 37.5 years (SD 20.7) vs. 44.9 years (SD 17.0), P = 0.026]. Flares occurred more frequently in patients without PV than in those with PV [mean number of flares per patient per year was 1.35 (SD 0.77) vs. 1.25 (SD 0.58), P = 0.039]. Common triggers of flares in patients with GPP who did not have PV were infections, pregnancy, menstruation and stress, whereas withdrawal of therapy, particularly systemic corticosteroids, was a more frequent trigger in patients with GPP who also had PV. CONCLUSIONS Our findings contribute to the global mapping of GPP, which will help inform the management of this rare condition.
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Affiliation(s)
- Siew Eng Choon
- Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health Sciences, Monash University, Selangor, Malaysia
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health
| | - Christopher E M Griffiths
- Centre for Dermatology Research, NIHR Manchester Biomedical Research Centre, University of Manchester, Manchester, UK
- Department of Dermatology, King's College Hospital, King's College London, London, UK
| | - Kit Wan Wong
- Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health Sciences, Monash University, Selangor, Malaysia
| | - Kwee Eng Tey
- Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health Sciences, Monash University, Selangor, Malaysia
| | - Yee Ting Lim
- Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health Sciences, Monash University, Selangor, Malaysia
| | - Keow Yin Chua
- Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health Sciences, Monash University, Selangor, Malaysia
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health
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Choon SE, Wright AK, Griffiths CE, Tey KE, Wong KW, Lee YW, Suvelayutnan U, Mariapun J, Ashcroft DM. Incidence and prevalence of psoriasis in multiethnic Johor Bahru, Malaysia: a population-based cohort study using electronic health data routinely captured in the Teleprimary Care (TPC®) clinical information system from 2010 to 2020: Classification: Epidemiology. Br J Dermatol 2022; 187:713-721. [PMID: 35830199 PMCID: PMC9804555 DOI: 10.1111/bjd.21768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/04/2022] [Accepted: 07/09/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND There are no population-based epidemiological data on psoriasis in Southeast Asia, including Malaysia. OBJECTIVES To determine the incidence and prevalence of psoriasis over 11 years in multiethnic Johor Bahru, Malaysia. METHODS A population-based cohort study was made using the Teleprimary Care database between January 2010 and December 2020. Cases of psoriasis, identified by ICD-10 diagnostic codes, were validated by dermatologists. Annual prevalence and incidence were estimated and stratified by age, sex and ethnicity. RESULTS We identified 3932 people with dermatologist-confirmed psoriasis, including 1830 incident cases, among 1 164 724 Malaysians, yielding an 11-year prevalence of 0·34% [95% confidence interval (CI) 0·33-0·35] and incidence of 34·2 per 100 000 person-years (95% CI 32·6-35·8). Rates were higher in Indian patients; the prevalences were 0·54% (0·50-0·58) in Indian, 0·38% (0·36-0·40) in Chinese and 0·29% (0·28-0·30) in Malay patients, and the respective incidences per 100 000 person-years were 52·5 (47·3-57·7), 38·0 (34·1-41·8) and 30·0 (28·2-31·8). Rates were higher in males; the prevalence was 0·39% (0·37-0·41) in males and 0·29% (0·27-0·30) in females, and the respective incidences per 100 000 person-years were 40·7 (38·2-43·2) and 28·3 (26·4-30·3). Between 2010 and 2020, annual psoriasis prevalence and incidence increased steadily from 0·27% to 0·51% and from 27·8 to 60·9 per 100 000 person-years, respectively. Annual rates were consistently higher in male and Indian patients. Overall, psoriasis was significantly more common in males than females [odds ratio (OR) 1·37, 95% CI 1·29-1·46] and in Indian and Chinese patients vs. Malay (OR 1·85, 1·71-2·01 and OR 1·30, 1·20-1·41, respectively). Prevalence increased with age, with the highest rates in the groups aged 50-59 and 60-69 years at 0·67% and 0·66%, respectively. A modest bimodal trend in age of psoriasis onset was observed, with first and second peaks at 20-29 and 50-59 years. Disease onset was significantly earlier in females than males [mean (SD) 36·8 (17·3) vs. 42·0 (17·2) years, P < 0·001] and in Malay vs. Indian and Chinese patients [mean (SD): Malay 36·4 (17·5), Indian 40·8 (15·2), Chinese 47·4 (16·9) years, P < 0·001]. CONCLUSIONS We found that psoriasis incidence and prevalence are increasing and varied by age, sex and ethnicity. Our findings should help inform healthcare planning and management for patients with psoriasis in Malaysia. What is already known about this topic? The incidence and prevalence of psoriasis are generally lower in Asian populations and children. There is a lack of agreement on sex-specific differences in psoriasis incidence and prevalence. There has been no population-based study on the incidence and prevalence of psoriasis in Southeast Asia, including Malaysia. There is no information on differences in psoriasis prevalence and incidence by sex, age and ethnicity in Malaysia. What does this study add? Psoriasis incidence and prevalence are increasing in the multiethnic population of Johor Bahru, Malaysia. Incidence and prevalence rates were higher in male than female patients and were consistently highest among Indian patients, followed by Chinese and Malay. A modest bimodality in the age of psoriasis onset was observed among the groups aged 20-29 and 50-59 years. Psoriasis onset was significantly later in male than female patients and in Chinese vs. Indian and Malay patients.
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Affiliation(s)
- Siew Eng Choon
- Department of DermatologyHospital Sultanah Aminah Johor BahruJohorMalaysia,Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health SciencesMonash UniversityJohorMalaysia
| | - Alison K. Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and HealthUniversity of ManchesterManchesterUK
| | - Christopher E.M. Griffiths
- NIHR Manchester Biomedical Research Centre, Manchester Academic Health Science CentreUniversity of ManchesterManchesterUK,Dermatology Centre, Salford Royal NHS Foundation Trust, Manchester Academic Health Science CentreUniversity of ManchesterManchesterUK
| | - Kwee Eng Tey
- Department of DermatologyHospital Sultanah Aminah Johor BahruJohorMalaysia,Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health SciencesMonash UniversityJohorMalaysia
| | - Kit Wan Wong
- Department of DermatologyHospital Sultanah Aminah Johor BahruJohorMalaysia,Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health SciencesMonash UniversityJohorMalaysia
| | - Yoong Wei Lee
- Department of DermatologyHospital Sultanah Aminah Johor BahruJohorMalaysia
| | - Ushananthiny Suvelayutnan
- Department of Information and Communication TechnologyHospital Sultanah Aminah Johor BahruJohorMalaysia
| | - Jeevitha Mariapun
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine & Health SciencesMonash UniversityJohorMalaysia
| | - Darren M. Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and HealthUniversity of ManchesterManchesterUK,NIHR Manchester Biomedical Research Centre, Manchester Academic Health Science CentreUniversity of ManchesterManchesterUK
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Wright AK, Carr MJ, Kontopantelis E, Leelarathna L, Thabit H, Emsley R, Buchan I, Mamas MA, van Staa TP, Sattar N, Ashcroft DM, Rutter MK. Primary Prevention of Cardiovascular and Heart Failure Events With SGLT2 Inhibitors, GLP-1 Receptor Agonists, and Their Combination in Type 2 Diabetes. Diabetes Care 2022; 45:909-918. [PMID: 35100355 DOI: 10.2337/dc21-1113] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 01/09/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To assess associations between current use of sodium-glucose cotransporter 2 inhibitors (SGLT2is), glucagon-like peptide 1 receptor agonists (GLP-1RAs), and their combination and risk for major adverse cardiac and cerebrovascular events (MACCE) and heart failure (HF) in people with type 2 diabetes. RESEARCH DESIGN AND METHODS In three nested case-control studies involving patients with type 2 diabetes in England and Wales (primary care data from the Clinical Practice Research Datalink and Secure Anonymised Information Linkage Databank with linkage to hospital and mortality records), we matched each patient experiencing an event with up to 20 control subjects. Adjusted odds ratios (ORs) for MACCE and HF among patients receiving SGLT2i or GLP-1RA regimens versus other combinations were estimated using conditional logistic regression and pooled using random-effects meta-analysis. RESULTS Among 336,334 people with type 2 diabetes and without cardiovascular disease, 18,531 (5.5%) experienced a MACCE. In a cohort of 411,206 with type 2 diabetes and without HF, 17,451 (4.2%) experienced an HF event. Compared with other combination regimens, the adjusted pooled OR and 95% CI for MACCE associated with SGLT2i regimens was 0.82 (0.73, 0.92), with GLP-1RA regimens 0.93 (0.81, 1.06), and with the SGLT2i/GLP-1RA combination 0.70 (0.50, 0.98). Corresponding data for HF were SGLT2i 0.49 (0.42, 0.58), GLP-1RA 0.82 (0.71, 0.95), and SGLT2i/GLP-1RA combination 0.43 (0.28, 0.64). CONCLUSIONS SGLT2i and SGLT2i/GLP-1RA combination regimens may be beneficial in primary prevention of MACCE and HF and GLP-1RA for HF. These data call for primary prevention trials using these agents and their combination.
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Affiliation(s)
- Alison K Wright
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, U.K.,Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, U.K
| | - Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, U.K.,National Institute for Health Research Greater Manchester Patient Safety Translational Research Centre, School of Health Sciences, University of Manchester, Manchester, U.K
| | - Evangelos Kontopantelis
- Division of Population Health, Health Services and Primary Care, School of Health Sciences, University of Manchester, Manchester, U.K
| | - Lalantha Leelarathna
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, U.K.,Diabetes, Endocrinology and Metabolism Centre, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, U.K
| | - Hood Thabit
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, U.K.,Diabetes, Endocrinology and Metabolism Centre, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, U.K
| | - Richard Emsley
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, U.K
| | - Iain Buchan
- Institute of Population Health, University of Liverpool, Liverpool, U.K
| | - Mamas A Mamas
- Keele Cardiovascular Group, Centre for Prognosis Research, Keele University, Keele, U.K
| | - Tjeerd P van Staa
- Division of Informatics, Imaging and Data Sciences, School of Health Sciences, University of Manchester, Manchester, U.K
| | - Naveed Sattar
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, U.K
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, U.K.,National Institute for Health Research Greater Manchester Patient Safety Translational Research Centre, School of Health Sciences, University of Manchester, Manchester, U.K
| | - Martin K Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, U.K.,Diabetes, Endocrinology and Metabolism Centre, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, U.K
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Alam NN, Wright AK, Rutter MK, Buchan I, Ashcroft DM, Sperrin M, Renehan AG. Body mass index and cancer mortality in patients with incident type 2 diabetes: A population-based study of adults in England. Diabetes Obes Metab 2022; 24:620-630. [PMID: 34866302 DOI: 10.1111/dom.14614] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 11/14/2021] [Accepted: 12/01/2021] [Indexed: 01/08/2023]
Abstract
AIMS We evaluated the relationship between body mass index (BMI) and cancer mortality in incident type 2 diabetes. METHODS We used the Clinical Practice Research Datalink GOLD (1998-2015), linked with the Office of National Statistics mortalities, and derived an incident type 2 diabetes cohort (N = 176 886; aged 30-85 years). We determined BMI ±12 months diabetes diagnosis. The primary outcome was cancer mortality, categorized into deaths from obesity-related cancers (ORCs) and non-ORCs. Secondary outcomes were site-specific cancer mortality and main causes of deaths [cancer, cardiovascular disease (CVD), non-cancer non-CVD]. We developed gender-specific Cox models and expressed risk as hazard ratios and 95% confidence intervals, stratified by smoking status. RESULTS With 886 850 person-years follow-up, 7593 cancer deaths occurred. Among women who never smoked, there were positive associations between BMI and deaths from endometrial (hazard ratios per 5 kg/m2 : 1.43; 95% confidence interval 1.26-1.61). Among men, associations between BMI and ORC mortality were inverse but attenuated towards null among never smokers and excluding deaths in the first 2 years. In men, the proportion of CVD deaths increased from 36.8% in BMI category 22.5 to 24.9 kg/m2 to 43.6% in BMI category ≥40 kg/m2 (p < .001). CONCLUSIONS We found some relationships between BMI and cancer mortality in patients with type 2 diabetes, but interpretations need to account for smoking status, reverse causality and deaths from CVD.
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Affiliation(s)
- Nasra N Alam
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, UK
| | - Martin K Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, UK
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, UK
| | - Iain Buchan
- Department of Public Health and Policy, Institute of Population Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
- Centre for Health Informatics, Division of Informatics, Imaging and Data Science, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, UK
| | - Matthew Sperrin
- Centre for Health Informatics, Division of Informatics, Imaging and Data Science, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Andrew G Renehan
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Centre for Health Informatics, Division of Informatics, Imaging and Data Science, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Cancer Research Centre, NIHR Manchester Biomedical Research Centre, University of Manchester, Manchester, UK
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Liu J, Richmond RC, Bowden J, Barry C, Dashti HS, Daghlas I, Lane JM, Jones SE, Wood AR, Frayling TM, Wright AK, Carr MJ, Anderson SG, Emsley RA, Ray DW, Weedon MN, Saxena R, Lawlor DA, Rutter MK. Assessing the Causal Role of Sleep Traits on Glycated Hemoglobin: A Mendelian Randomization Study. Diabetes Care 2022; 45:772-781. [PMID: 35349659 PMCID: PMC9114722 DOI: 10.2337/dc21-0089] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 11/18/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To examine the effects of sleep traits on glycated hemoglobin (HbA1c). RESEARCH DESIGN AND METHODS This study triangulated evidence across multivariable regression (MVR) and one- (1SMR) and two-sample Mendelian randomization (2SMR) including sensitivity analyses on the effects of five self-reported sleep traits (i.e., insomnia symptoms [difficulty initiating or maintaining sleep], sleep duration, daytime sleepiness, napping, and chronotype) on HbA1c (in SD units) in adults of European ancestry from the UK Biobank (for MVR and 1SMR analyses) (n = 336,999; mean [SD] age 57 [8] years; 54% female) and in the genome-wide association studies from the Meta-Analyses of Glucose and Insulin-Related Traits Consortium (MAGIC) (for 2SMR analysis) (n = 46,368; 53 [11] years; 52% female). RESULTS Across MVR, 1SMR, 2SMR, and their sensitivity analyses, we found a higher frequency of insomnia symptoms (usually vs. sometimes or rarely/never) was associated with higher HbA1c (MVR 0.05 SD units [95% CI 0.04-0.06]; 1SMR 0.52 [0.42-0.63]; 2SMR 0.24 [0.11-0.36]). Associations remained, but point estimates were somewhat attenuated after excluding participants with diabetes. For other sleep traits, there was less consistency across methods, with some but not all providing evidence of an effect. CONCLUSIONS Our results suggest that frequent insomnia symptoms cause higher HbA1c levels and, by implication, that insomnia has a causal role in type 2 diabetes. These findings could have important implications for developing and evaluating strategies that improve sleep habits to reduce hyperglycemia and prevent diabetes.
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Affiliation(s)
- Junxi Liu
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, U.K
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, U.K
| | - Rebecca C. Richmond
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, U.K
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, U.K
| | - Jack Bowden
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, U.K
- College of Medicine and Health, University of Exeter, Exeter, U.K
| | - Ciarrah Barry
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, U.K
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, U.K
| | - Hassan S. Dashti
- Centre for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Iyas Daghlas
- Centre for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Jacqueline M. Lane
- Centre for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Samuel E. Jones
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - Andrew R. Wood
- Genetics of Complex Traits, University of Exeter Medical School, Exeter, U.K
| | - Timothy M. Frayling
- Genetics of Complex Traits, University of Exeter Medical School, Exeter, U.K
| | - Alison K. Wright
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
| | - Matthew J. Carr
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
- Manchester Academic Health Science Centre, University of Manchester, Manchester, U.K
- National Institute for Health Research (NIHR) Greater Manchester Patient Safety Translational Research Centre, University of Manchester, Manchester, U.K
| | - Simon G. Anderson
- George Alleyne Chronic Disease Research Centre, Caribbean Institute of Health Research, University of the West Indies, Kingston, Jamaica
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
| | - Richard A. Emsley
- Department of Biostatistics and Health Informatics, King’s College London, London, U.K
| | - David W. Ray
- NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, U.K
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, U.K
| | - Michael N. Weedon
- Genetics of Complex Traits, University of Exeter Medical School, Exeter, U.K
| | - Richa Saxena
- Centre for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Deborah A. Lawlor
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, U.K
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, U.K
- NIHR Bristol Biomedical Research Centre, University Hospitals Bristol National Health Service (NHS) Foundation Trust, University of Bristol, Bristol, U.K
| | - Martin K. Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, U.K
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, U.K
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Carr MJ, Wright AK, Leelarathna L, Thabit H, Milne N, Kanumilli N, Ashcroft DM, Rutter MK. Impact of COVID-19 restrictions on diabetes health checks and prescribing for people with type 2 diabetes: a UK-wide cohort study involving 618 161 people in primary care. BMJ Qual Saf 2021; 31:503-514. [PMID: 34642228 PMCID: PMC8520602 DOI: 10.1136/bmjqs-2021-013613] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/25/2021] [Indexed: 12/22/2022]
Abstract
Objective To compare rates of performing National Institute for Health and Care Excellence-recommended health checks and prescribing in people with type 2 diabetes (T2D), before and after the first COVID-19 peak in March 2020, and to assess whether trends varied by age, sex, ethnicity and deprivation. Methods We studied 618 161 people with T2D followed between March and December 2020 from 1744 UK general practices registered with the Clinical Practice Research Datalink. We focused on six health checks: haemoglobin A1c, serum creatinine, cholesterol, urinary albumin excretion, blood pressure and body mass index assessment. Regression models compared observed rates in April 2020 and between March and December 2020 with trend-adjusted expected rates derived from 10-year historical data. Results In April 2020, in English practices, rates of performing health checks were reduced by 76%–88% when compared with 10-year historical trends, with older people from deprived areas experiencing the greatest reductions. Between May and December 2020, the reduced rates recovered gradually but overall remained 28%–47% lower, with similar findings in other UK nations. Extrapolated to the UK population, there were ~7.4 million fewer care processes undertaken March–December 2020. In England, rates for new medication fell during April with reductions varying from 10% (95% CI: 4% to 16%) for antiplatelet agents to 60% (95% CI: 58% to 62%) for antidiabetic medications. Overall, between March and December 2020, the rate of prescribing new diabetes medications fell by 19% (95% CI: 15% to 22%) and new antihypertensive medication prescribing fell by 22% (95% CI: 18% to 26%), but prescribing of new lipid-lowering or antiplatelet therapy was unchanged. Similar trends were observed across the UK, except for a reduction in new lipid-lowering therapy prescribing in the other UK nations (reduction: 16% (95% CI: 10% to 21%)). Extrapolated to the UK population, between March and December 2020, there were ~31 800 fewer people with T2D prescribed a new type of diabetes medication and ~14 600 fewer prescribed a new type of antihypertensive medication. Conclusions Over the coming months, healthcare services will need to manage this backlog of testing and prescribing. We recommend effective communications to ensure patient engagement with diabetes services, monitoring and opportunities for prescribing, and when appropriate use of home monitoring, remote consultations and other innovations in care.
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Affiliation(s)
- Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, The University of Manchester, Manchester, UK .,NIHR Greater Manchester Patient Safety Translational Research Centre, University of Manchester, Manchester, UK
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, The University of Manchester, Manchester, UK.,Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, The University of Manchester, Manchester, UK
| | - Lalantha Leelarathna
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, The University of Manchester, Manchester, UK.,Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Hood Thabit
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, The University of Manchester, Manchester, UK.,Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Nicola Milne
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Naresh Kanumilli
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, The University of Manchester, Manchester, UK.,NIHR Greater Manchester Patient Safety Translational Research Centre, University of Manchester, Manchester, UK
| | - Martin K Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, The University of Manchester, Manchester, UK.,Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
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Khawagi WY, Steinke D, Carr MJ, Wright AK, Ashcroft DM, Avery A, Keers RN. Evaluating the safety of mental health-related prescribing in UK primary care: a cross-sectional study using the Clinical Practice Research Datalink (CPRD). BMJ Qual Saf 2021; 31:364-378. [PMID: 34433681 PMCID: PMC9046740 DOI: 10.1136/bmjqs-2021-013427] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 08/07/2021] [Indexed: 01/28/2023]
Abstract
Background Most patients with mental illness are managed in primary care, yet there is a lack of data exploring potential prescribing safety issues in this setting for this population. Objectives Examine the prevalence of, between-practice variation in, and patient and practice-level risk factors for, 18 mental health-related potentially hazardous prescribing indicators and four inadequate medication monitoring indicators in UK primary care. Method Cross-sectional analyses of routinely collected electronic health records from 361 practices contributing to Clinical Practice Research Datalink GOLD database. The proportion of patients ‘at risk’ (based on an existing diagnosis, medication, age and/or sex) triggering each indicator and composite indicator was calculated. To examine between-practice variation, intraclass correlation coefficient (ICC) and median OR (MOR) were estimated using two-level logistic regression models. The relationship between patient and practice characteristics and risk of triggering composites including 16 of the 18 prescribing indicators and four monitoring indicators were assessed using multilevel logistic regression. Results 9.4% of patients ‘at risk’ (151 469 of 1 611 129) triggered at least one potentially hazardous prescribing indicator; between practices this ranged from 3.2% to 24.1% (ICC 0.03, MOR 1.22). For inadequate monitoring, 90.2% of patients ‘at risk’ (38 671 of 42 879) triggered at least one indicator; between practices this ranged from 33.3% to 100% (ICC 0.26, MOR 2.86). Patients aged 35–44, females and those receiving more than 10 repeat prescriptions were at greatest risk of triggering a prescribing indicator. Patients aged less than 25, females and those with one or no repeat prescription were at greatest risk of triggering a monitoring indicator. Conclusion Potentially hazardous prescribing and inadequate medication monitoring commonly affect patients with mental illness in primary care, with marked between-practice variation for some indicators. These findings support health providers to identify improvement targets and inform development of improvement efforts to reduce medication-related harm.
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Affiliation(s)
- Wael Y Khawagi
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Department of Clinical Pharmacy, College of Pharmacy, Taif University, Taif, Saudi Arabia
| | - Douglas Steinke
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre, Manchester, UK
| | - Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- NIHR Greater Manchester Patient Safety Translational Research Centre, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- NIHR Greater Manchester Patient Safety Translational Research Centre, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Anthony Avery
- NIHR Greater Manchester Patient Safety Translational Research Centre, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Division of Primary Care, School of Medicine, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
| | - Richard Neil Keers
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Pharmacy Department, Greater Manchester Mental Health NHS Foundation Trust, Manchester, UK
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Carr MJ, Wright AK, Leelarathna L, Thabit H, Milne N, Kanumilli N, Ashcroft DM, Rutter MK. Impact of COVID-19 on diagnoses, monitoring, and mortality in people with type 2 diabetes in the UK. Lancet Diabetes Endocrinol 2021; 9:413-415. [PMID: 33989537 PMCID: PMC8112824 DOI: 10.1016/s2213-8587(21)00116-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/05/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023]
Affiliation(s)
- Matthew J Carr
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK; NIHR Greater Manchester Patient Safety Translational Research Centre, University of Manchester, Manchester, UK.
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK
| | - Lalantha Leelarathna
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Hood Thabit
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Nicola Milne
- Manchester Academic Health Science Centre, Manchester, UK; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Naresh Kanumilli
- Manchester Academic Health Science Centre, Manchester, UK; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK; NIHR Greater Manchester Patient Safety Translational Research Centre, University of Manchester, Manchester, UK
| | - Martin K Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK; Manchester Academic Health Science Centre, Manchester, UK; Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester, UK
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11
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Wright AK, Suarez-Ortegon MF, Read SH, Kontopantelis E, Buchan I, Emsley R, Sattar N, Ashcroft DM, Wild SH, Rutter MK. Risk Factor Control and Cardiovascular Event Risk in People With Type 2 Diabetes in Primary and Secondary Prevention Settings. Circulation 2020; 142:1925-1936. [PMID: 33196309 PMCID: PMC7664968 DOI: 10.1161/circulationaha.120.046783] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 09/10/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND To examine the association between the degree of risk factor control and cardiovascular disease (CVD) risk in type 2 diabetes and to assess if the presence of cardio-renal disease modifies these relationships. METHODS A retrospective cohort study using data from English practices from CPRD GOLD (Clinical Practice Research Datalink) and the SCI-Diabetes dataset (Scottish Care Information-Diabetes), with linkage to hospital and mortality data. We identified 101 749 with type 2 diabetes (T2D) in CPRD matched with 378 938 controls without diabetes and 330 892 with type 2 diabetes in SCI-Diabetes between 2006 and 2015. The main exposure was number of optimized risk factors: nonsmoker, total cholesterol ≤4 mmol/L, triglycerides ≤1.7 mmol/L, glycated haemoglobin (HbA1c) ≤53 mmol/mol (≤7.0%), systolic blood pressure <140mm Hg, or <130 mm Hg if high risk. Cox models were used to assess cardiovascular risk associated with levels of risk factor control. RESULTS In CPRD, the mean baseline age in T2D was 63 years and 28% had cardio-renal disease (SCI-Diabetes: 62 years; 35% cardio-renal disease). Over 3 years follow-up (SCI-Diabetes: 6 years), CVD events occurred among 27 900 (27%) CPRD-T2D, 101 362 (31%) SCI-Diabetes-T2D, and 75 520 (19%) CPRD-controls. In CPRD, compared with controls, T2D participants with optimal risk factor control (all risk factors controlled) had a higher risk of CVD events (adjusted hazard ratio, 1.21; 95% confidence interval, 1.12-1.29). In T2D participants from CPRD and SCI-Diabetes, pooled hazard ratios for CVD associated with 5 risk factors being elevated versus optimal risk factor control were 1.09 (95% confidence interval, 1.01-1.17) in people with cardio-renal disease but 1.96 (95% confidence interval, 1.82-2.12) in people without cardio-renal disease. People without cardio-renal disease were younger and more likely to have likely to have suboptimal risk factor control but had fewer prescriptions for risk factor modifying medications than those with cardio-renal disease. CONCLUSIONS Optimally managed people with T2D have a 21% higher CVD risk when compared with controls. People with T2D without cardio-renal disease would be predicted to benefit greatly from CVD risk factor intervention.
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Affiliation(s)
- Alison K. Wright
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, United Kingdom (A.K.W., M.K.R.)
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, United Kingdom (A.K.W., D.M.A.)
| | - Milton Fabian Suarez-Ortegon
- Departamento de Alimentación y Nutrición, Facultad de Ciencias de la Salud, Pontificia Universidad Javeriana Seccional Cali, Colombia (M.F.S.-O.)
- Grupo de Investigación en Ciencias Básicas y Clínicas de la Salud, Facultad de Ciencias de la Salud, Pontificia Universidad Javeriana Seccional Cali, Colombia (M.F.S.-O.)
| | - Stephanie H. Read
- Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, United Kingdom (S.H.R., S.H.W.)
- Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada (S.H.R.)
- Scottish Diabetes Research Network epidemiology group, Scotland, United Kingdom (S.H.W.)
| | - Evangelos Kontopantelis
- Division of Informatics, Imaging and Data Sciences, School of Health Sciences, University of Manchester, United Kingdom (E.K.)
| | - Iain Buchan
- Department of Public Health and Policy, Institute of Population Health Sciences, University of Liverpool, United Kingdom (I.B.)
- Health eResearch Center, Farr Institute, Division of Informatics, Imaging & Data Sciences, School of Health Sciences, University of Manchester, United Kingdom (I.B.)
| | - Richard Emsley
- Department of Biostatistics & Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, United Kingdom (R.E.)
| | - Naveed Sattar
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, United Kingdom (N.S.)
| | - Darren M. Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, United Kingdom (A.K.W., D.M.A.)
| | - Sarah H. Wild
- Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, United Kingdom (S.H.R., S.H.W.)
| | - Martin K. Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, United Kingdom (A.K.W., M.K.R.)
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, United Kingdom (M.K.R.)
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12
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Wright AK, Welsh P, Gill JMR, Kontopantelis E, Emsley R, Buchan I, Ashcroft DM, Rutter MK, Sattar N. Age-, sex- and ethnicity-related differences in body weight, blood pressure, HbA 1c and lipid levels at the diagnosis of type 2 diabetes relative to people without diabetes. Diabetologia 2020; 63:1542-1553. [PMID: 32435821 PMCID: PMC7351865 DOI: 10.1007/s00125-020-05169-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/02/2020] [Indexed: 11/30/2022]
Abstract
AIMS/HYPOTHESIS The aim of this work was to determine how weight patterns together with blood glucose, BP and lipids vary at diagnosis of diabetes by age, sex and ethnicity. METHODS Using the UK Clinical Practice Research Datalink, we identified people with type 2 diabetes (n = 187,601) diagnosed in 1998-2015 and compared their weights, HbA1c, BP and lipid levels at diagnosis with age-matched people without diabetes (n = 906,182), by sex and ethnic group. RESULTS Younger age at diagnosis was associated with greater adjusted mean difference (95% CI) in weight between those with vs without type 2 diabetes: 18.7 (18.3, 19.1) kg at age 20-39 years and 5.3 (5.0, 5.5) kg at age ≥ 80 years. Weight differentials were maximal in white women, and were around double in white people compared with South Asian and black people. Despite lower absolute values, BP differences were also greater at younger age of diabetes onset: 7 (6, 7) mmHg at age 20-39 years vs -0.5 (-0.9, -0.2) at age ≥ 80 years. BP differences were greatest in white people, and especially in women. Triacylglycerol level differences were greatest in younger men. Finally, HbA1c levels were also higher with younger onset diabetes, particularly in black people. CONCLUSIONS/INTERPRETATION At diagnosis of type 2 diabetes, when compared with people without diabetes, weight and BP differentials were greater in younger vs older people, in women vs men and in white vs South Asian and black people. These differences were observed even though South Asian and black people tend to develop diabetes a decade earlier with either similar or greater dysglycaemia. These striking patterns may have implications for management and prevention. Graphical abstract.
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Affiliation(s)
- Alison K Wright
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, UK
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
| | - Paul Welsh
- Institute of Cardiovascular & Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK
| | - Jason M R Gill
- Institute of Cardiovascular & Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK
| | - Evangelos Kontopantelis
- Division of Population Health, Health Services & Primary Care, School of Health Sciences, University of Manchester, Manchester, UK
| | - Richard Emsley
- Department of Biostatistics & Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Iain Buchan
- Department of Public Health and Policy, Institute of Population Health Sciences, University of Liverpool, Liverpool, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
| | - Martin K Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, University of Manchester, Manchester, UK
- Manchester Diabetes Centre, Manchester Academic Health Sciences Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Naveed Sattar
- Institute of Cardiovascular & Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK.
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Affiliation(s)
- Nasra Alam
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Andrew G Renehan
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK; Manchester Cancer Research Centre, National Institute for Health Research, Manchester Biomedical Research Centre, Manchester, M20 4BX, UK.
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14
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Wright AK, Kontopantelis E, Emsley R, Buchan I, Mamas MA, Sattar N, Ashcroft DM, Rutter MK. Cardiovascular Risk and Risk Factor Management in Type 2 Diabetes Mellitus: A Population-Based Cohort Study Assessing Sex Disparities. Circulation 2019; 139:2742-2753. [PMID: 30986362 DOI: 10.1161/circulationaha.118.039100] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND With recent changes in the United Kingdom's clinical practice for diabetes mellitus care, contemporary estimates of sex disparities in cardiovascular risk and risk factor management are needed. METHODS In this retrospective cohort study, using the Clinical Practice Research Datalink linked to hospital and death records for people in England, we identified 79 985 patients with incident type 2 diabetes mellitus (T2DM) between 2006 to 2013 matched to 386 547 patients without diabetes mellitus. Sex-stratified Cox models were used to assess cardiovascular risk. RESULTS Compared with women without T2DM, women with T2DM had a higher cardiovascular event risk (adjusted hazard ratio, 1.20 [95% confidence interval, 1.12-1.28]) with similar corresponding data in men (hazard ratio, 1.12 [1.06-1.19]), leading to a nonsignificant higher relative risk in women (risk ratio, 1.07 [0.98-1.17]). However, some important sex differences in the management of risk factors were observed. Compared with men with T2DM, women with T2DM were more likely to be obese, hypertensive, and have hypercholesterolemia, but were less likely to be prescribed lipid-lowering medication and angiotensin-converting enzyme inhibitors, especially if they had cardiovascular disease. CONCLUSIONS Compared with men developing T2DM, women with T2DM do not have a significantly higher relative increase in cardiovascular risk, but ongoing sex disparities in prescribing should prompt heightened efforts to improve the standard and equity of diabetes mellitus care in women and men.
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Affiliation(s)
- Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Manchester Academic Health Sciences Centre (A.K.W., D.M.A.)
- Division of Diabetes, Endocrinology, and Gastroenterology, School of Medical Sciences (A.K.W., M.K.R.)
| | - Evangelos Kontopantelis
- Division of Population Health, Health Services, & Primary Care, School of Health Sciences, (E.K.)
| | - Richard Emsley
- Department of Biostatistics & Health Informatics, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, UK (R.E.)
| | - Iain Buchan
- Health eResearch Center, Farr Institute, Division of Informatics, Imaging & Data Sciences, School of Health Sciences (I.B.), University of Manchester
- Department of Public Health and Policy, Institute of Population Health Sciences, University of Liverpool, UK (I.B.)
| | - Mamas A Mamas
- Keele Cardiovascular Group, Centre for Prognosis Research, Keele University, Stoke-on-Trent, UK (M.A.M.)
| | - Naveed Sattar
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, UK (N.S.)
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy and Optometry, School of Health Sciences, Manchester Academic Health Sciences Centre (A.K.W., D.M.A.)
| | - Martin K Rutter
- Division of Diabetes, Endocrinology, and Gastroenterology, School of Medical Sciences (A.K.W., M.K.R.)
- Manchester Diabetes Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre (M.K.R.), UK
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Wright AK, Kontopantelis E, Emsley R, Buchan I, Sattar N, Rutter MK, Ashcroft DM. Life Expectancy and Cause-Specific Mortality in Type 2 Diabetes: A Population-Based Cohort Study Quantifying Relationships in Ethnic Subgroups. Diabetes Care 2017; 40:338-345. [PMID: 27998911 DOI: 10.2337/dc16-1616] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 11/30/2016] [Indexed: 02/03/2023]
Abstract
OBJECTIVES This study 1) investigated life expectancy and cause-specific mortality rates associated with type 2 diabetes and 2) quantified these relationships in ethnic subgroups. RESEARCH DESIGN AND METHODS This was a cohort study using Clinical Practice Research Datalink data from 383 general practices in England with linked hospitalization and mortality records. A total of 187,968 patients with incident type 2 diabetes from 1998 to 2015 were matched to 908,016 control subjects. Abridged life tables estimated years of life lost, and a competing risk survival model quantified cause-specific hazard ratios (HRs). RESULTS A total of 40,286 deaths occurred in patients with type 2 diabetes. At age 40, white men with diabetes lost 5 years of life and white women lost 6 years compared with those without diabetes. A loss of between 1 and 2 years was observed for South Asians and blacks with diabetes. At age older than 65 years, South Asians with diabetes had up to 1.1 years' longer life expectancy than South Asians without diabetes. Compared with whites with diabetes, South Asians with diabetes had lower adjusted risks for mortality from cardiovascular (HR 0.82; 95% CI 0.75, 0.89), cancer (HR 0.43; 95% CI 0.36, 0.51), and respiratory diseases (HR 0.60; 95% CI 0.48, 0.76). A similar pattern was observed in blacks with diabetes compared with whites with diabetes. CONCLUSIONS Type 2 diabetes was associated with more years of life lost among whites than among South Asians or blacks, with older South Asians experiencing longer life expectancy compared with South Asians without diabetes. The findings support optimized cardiovascular disease risk factor management, especially in whites with type 2 diabetes.
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Affiliation(s)
- Alison K Wright
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy & Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K.,Division of Diabetes, Endocrinology & Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K
| | - Evangelos Kontopantelis
- The Farr Institute of Health Informatics Research, Division of Informatics, Imaging & Data Science, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K
| | - Richard Emsley
- Centre for Biostatistics, Division of Population Health, Health Services Research & Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K
| | - Iain Buchan
- The Farr Institute of Health Informatics Research, Division of Informatics, Imaging & Data Science, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K
| | - Naveed Sattar
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, U.K
| | - Martin K Rutter
- Division of Diabetes, Endocrinology & Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K.,Manchester Diabetes Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, U.K
| | - Darren M Ashcroft
- Centre for Pharmacoepidemiology and Drug Safety, Division of Pharmacy & Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K.
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Abstract
Lesioning or stimulating the subthalamic nucleus (STN) in patients with Parkinson's disease, or in animal models of parkinsonism, alleviates many of the symptoms and so it is tempting to think of the STN as a part of the cause of Parkinson's disease. The globus pallidus (GP) is thought to have a tonic inhibitory action on the STN. An ibotenic acid injection into the GP in rats removes the cells of the GP and, over the following 6 weeks, a progressive loss of dopamine cells (counted stereologically in sections stained for tyrosine hydroxylase) develops in substantia nigra (SN). In this investigation we show that, when animals have the STN cells destroyed by very small ibotenic acid injections, their dopamine neurons are not damaged. Furthermore, if a lesion to the GP follows a lesion of STN then the dopamine cells also survive this double insult, at least for the first 3 weeks following the lesion. The experiments provide good reason to suspect that, at least in the short term, increased activity in the STN is a contributory cause of the loss of dopamine cells which follows the lesion of the GP in rats. Whether or not this is part of the mechanism of cell loss in Parkinson's disease, the rats with GP lesions at least provide an opportunity to test strategies that might protect dopamine cells from slowly developing damage. Removing the STN seems to be neuroprotective in this new model of dopamine degeneration.
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Affiliation(s)
- A K Wright
- Division of Neuroscience, University of Edinburgh, EH9 1QH, Scotland, UK
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17
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Abstract
Parkinson's disease is a debilitating disorder that results from the death of dopaminergic neurones in the substantia nigra. Subthalamic nucleus neurones use glutamate as their neurotransmitter and send excitatory projections to the substantia nigra. Changes in both the mean firing rate and firing pattern of neurones of the subthalamic nucleus have been found in patients with this disease. This has led to the suggestion that hyperactivity of the subthalamic nucleus may be involved in the pathology of the dopaminergic neurones. Subthalamic nucleus lesions or treatment with glutamatergic antagonists can be neuroprotective in animal models of Parkinson's disease but until now there has been no direct evidence that hyperactivity of subthalamic nucleus neurones can lead to downstream cell death. Here we show that lesions of the rat globus pallidus (a treatment that has been shown to increase subthalamic nucleus neuronal activity) result in a significant reduction of the number of dopaminergic neurones in the substantia nigra.
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Affiliation(s)
- A K Wright
- The University of Edinburgh Division of Neuroscience, Veterinary Biological Sciences, R(D)SVS, Summerhall, Edinburgh EH9 1QH, UK
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18
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Wright AK, Ramanathan S, Arbuthnott GW. Identification of the source of the bilateral projection system from cortex to somatosensory neostriatum and an exploration of its physiological actions. Neuroscience 2001; 103:87-96. [PMID: 11311789 DOI: 10.1016/s0306-4522(00)00564-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Microinjections of cholera toxin B subunit were made into the area of the neostriatum that receives input from the primary somatosensory barrel cortex (SI) in the rat. Studies of the cortices then allowed retrograde identification of the cortical cells supplying the striatal input. When injections were restricted to the neostriatum, retrograde labelling was found in layer V of both SI cortices. Ipsilateral to the injection, cells were retrogradely filled with toxin in all parts of the barrel field, in adjacent parietal cortex, in the motor cortex and in prefrontal areas. A similar distribution across cortical areas was seen contralaterally; however, the stained cells in the SI were between rather than within barrel columns. An earlier anterograde study suggested two inputs from the SI to the neostriatum. The present results indicate that one input to the somatosensory area of the neostriatum arises bilaterally from neurons between the barrels of the SI, while the topographic pathway from below the barrels is present only ipsilaterally. These anatomical results indicate that separate stimulation of the two corticostriatal pathways from the barrel cortex is possible. Electrical stimulation of the contralateral cortex will activate the bilateral pathway, while electrical stimulation of the whisker pads activates the barrels and hence the topographic pathway. Neurons in the somatosensory region of the striatum responded to stimuli in the contralateral cortex and in the contralateral whisker pad. In spite of very different path lengths, stimuli via the two routes gave rise to excitatory postsynaptic potentials in the striatal cells with similar latencies. The excitatory postsynaptic potentials to whisker pad stimulation had a rapid rise time and usually resulted in at least one action potential. Responses to stimulation of the contralateral cortex rose to a peak more slowly and were more variable in latency, but also gave rise to an action potential in the majority of cases. All the neurons had the physiological characteristics of medium-sized densely spiny cells and after intracellular filling with biocytin had the appropriate morphology. In summary, we propose that two corticostriatal pathways arise from layer V cells in the barrel area of the somatosensory cortex; one is bilateral and arises from cells mainly below the septa, while a topographical pathway arises from cells below the barrels. Both pathways can raise the spiny output cells of the striatum to firing threshold. The latencies from the contralateral cortex imply slowly conducting fibres with considerably more temporal dispersion than the pathway from below the barrels, which we excited from the contralateral periphery.
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Affiliation(s)
- A K Wright
- University of Edinburgh Centre for Neuroscience, Department of Preclinical Veterinary Sciences, Summerhall, Edinburgh EH9 1QH, UK
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19
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Abstract
The cortical representations of the vibrissae of the rat form a matrix in which each whisker has its own area of cortex, called a 'barrel'. The afferent pathways from the periphery travel first to the trigeminal nuclei and thence via the ventroposteromedial thalamus (VPM) to the cortical barrels have been described in detail. We have studied the output from barrels by filling adjacent areas of the primary somatosensory cortex (SI) with either Phaseolus vulgaris leucoagglutinin (PHA-L) or biotinylated dextran amine (BDA) and demonstrating the course and terminations of the axons that arise within the barrel fields. The method not only dramatically illustrates the previously described corticothalamic pathway to VPM but also demonstrates a strict topography in the cortical afferents to the thalamic reticular nucleus (RT). Cells supplying the RT projection are found below the barrels in layer IV. Connections to the posterior thalamus, on the other hand, have no discernible topography and are derived from cortical areas surrounding the barrels. Thus the outputs of these 'septal' areas return to the region from which they receive thalamic input. The corticocortical connections are also visible in the same material. Contralateral cortical connections arise from the cells of the septa between barrels. The projections to secondary somatosensory area (SII) are mirror images of the barrel pattern in SI with rather more overlap but nonetheless a recognisable topography.
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Affiliation(s)
- A K Wright
- University of Edinburgh Centre for Neuroscience, Department of Preclinical Veterinary Sciences, Scotland, UK
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20
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Wright AK, Norrie L, Ingham CA, Hutton EA, Arbuthnott GW. Double anterograde tracing of outputs from adjacent "barrel columns" of rat somatosensory cortex. Neostriatal projection patterns and terminal ultrastructure. Neuroscience 1999; 88:119-33. [PMID: 10051194 DOI: 10.1016/s0306-4522(98)00186-9] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The sensory input to the neostriatum from groups of cortical cells related to individual facial vibrissae has been investigated at both light- and electron-microscopic resolution. The purpose of the study was to establish the extent to which corticostriatal input maintains the anatomical coding of spatial information that is present in cortex. A double anterograde tracing method was used to identify the output projections from groups of adjacent neurons in different barrel columns, so that the anatomical relationships between two groups could be studied throughout their length. Adjacent whiskers are represented in adjoining cortical barrels and an examination of corticostriatal projections from these reveals two patterns of projection. In one, the anatomical topography is partially preserved; the barrels are represented in adjoining, discrete, areas of the somatosensory neostriatum. In the second projection pattern, the neostriatal innervation is diffuse and adjacent barrels are represented in overlapping regions of the neostriatum. Moreover, the fibres are thinner, have smaller boutons, and are present in both the ipsilateral and contralateral neostriatum. The two systems also enter the neostriatal neuropile separately. The discrete topographic system enters the adjacent neostriatum as collaterals which leave the descending corticofugal fibres at right angles, while the diffuse system enters directly from the corpus callosum at an acute angle. Examination of the neostriatal terminal fields by correlated light and electron microscopy, shows that characteristic axospinous terminals on spiny neurons are made by both groups of cortical fibres, although they differ in their size and morphology. It is concluded that at least two corticostriatal pathways arise from the barrel cortex. One connection maintains some of the anatomical code implicit in the barrel pattern of primary somatosensory cortex, but another, more diffuse, system is overlaid upon it which may carry different information from this complex area of cortex.
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Affiliation(s)
- A K Wright
- University of Edinburgh Centre for Neuroscience, Department of Preclinical Veterinary Sciences, Summerhall, UK
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21
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Ellis JA, Steeves E, Wright AK, Bogdan JR, Davis WC, Kanara EW, Haines DM. Cell-mediated cytolysis of equine herpesvirus-infected cells by leukocytes from young vaccinated horses. Vet Immunol Immunopathol 1997; 57:201-14. [PMID: 9261959 DOI: 10.1016/s0165-2427(96)05749-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The objective of this study was to determine whether the administration of modified-live equine herpesvirus (EHV-1) to young horses with residual maternal antibodies stimulated EHV-specific cytolytic responses, and whether these responses were crossreactive between EHV-1 and EHV-4. Eighteen clinically normal Belgian cross-foals were used in the study and were commingled in two adjacent pens. Skin biopsies were harvested from 16 foals within 24 h of birth and fibroblast cultures were established, expanded and cryopreserved. Beginning at approximately 10 weeks of age, 10 randomly chosen foals were inoculated on days 0, 21, and 43 of the study with a vaccine containing modified-live EHV-1. Blood mononuclear leukocytes were obtained on days 0, 32, and 50 for the assessment of EHV-specific cytolytic activity using 5 h and 18 h chromium release assays. EHV-1-specific antibodies were assessed by enzyme-linked immunosorbent assay using serum collected on days -21, 0, 32, and 50 of the study. Lymphocyte blastogenic tests and bioassays for interferon activity were conducted on day 50. After two vaccinations, mononuclear leukocytes from seven of ten vaccinated foals had cytolytic activity against autologous EHV-1 cells and leukocytes from six of ten lysed EHV-4-infected cells when tested in an 18 h assay. This activity was enhanced by exogenous interleukin 2 and was markedly reduced using target cells from unrelated horses. Cytotoxicity was not detected in a 5 h assay following in vitro stimulation of leukocytes. After three vaccinations, blood leukocytes from 6/6 vaccinated foals and 0/6 unvaccinated foals had proliferative responses EHV-1. There were no significant differences in interferon production by leukocytes from these foals. Twelve foals tested had low concentrations of (maternal) EHV-1-specific antibody prior to vaccination. Five of eight foals tested had increases in EHV-specific antibodies, while 4/4 commingled unvaccinated foals had a decrease or no change in EHV-specific antibodies. These results demonstrate cytotoxic cellular immune responses can be induced in young horses with maternal antibodies following administration of modified-live vaccine.
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Affiliation(s)
- J A Ellis
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, Canada
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22
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Affiliation(s)
- M G Papich
- Department of Anatomy, Physiological Sciences, and Radiology, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA
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23
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Kasper CA, Clayton HM, Wright AK, Skuba EV, Petrie L. Effects of high doses of oxytetracycline on metacarpophalangeal joint kinematics in neonatal foals. J Am Vet Med Assoc 1995; 207:71-3. [PMID: 7601698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Thirteen clinically normal Belgian-type foals were used to study the effects of high doses of oxytetracycline on metacarpophalangeal joint kinematics. Seven foals (treatment group) received 2 doses of oxytetracycline (3 g, IV). The first dose was given when foals were 4 days old; the second dose was given 24 hours later. Six foals (control group) received 2 doses of saline (0.9% NaCl) solution (15 ml, IV) at equivalent time periods. All foals were videotaped at a walk twice: immediately prior to the first treatment and 24 hours after the second treatment. The tapes were digitized, and metacarpophalangeal joint angle was measured along the palmar surface of the limb during 3 strides. The angular data were normalized for time, and data from the 3 strides were averaged to describe a representative stride. Repeated measures ANOVA was used to test for differences between groups and within groups over time. Values for stride duration, stance phase percentage, and minimum metacarpophalangeal joint angle obtained before treatment were not significantly different from values obtained after treatment. Maximum metacarpophalangeal joint angle, which occurred during the stance phase of the stride, and range of joint motion were significantly increased for foals in the treatment group, compared with foals in the control group.
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Affiliation(s)
- C A Kasper
- Department of Veterinary Anesthesiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
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24
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Wright AK, Giger R, Arnold TM, Janzen ED. An episode of diarrhea in calves of a well-managed dairy herd. Can Vet J 1995; 36:36-8. [PMID: 7859212 PMCID: PMC1687215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- A K Wright
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon
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25
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Bloch EF, Rahbar M, Wright AK, Patterson AM, Souza RF, Hammer CH, Gaither TA, Joiner KA. Potassium cyanide protects Escherichia coli from complement killing by the inhibition of C3 convertase activity. Immunol Invest 1993; 22:127-49. [PMID: 8505069 DOI: 10.3109/08820139309063396] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The exact mechanism by which deposited C5b-9 complexes kill Gram-negative bacteria is unclear. It has been proposed that during complement activation the membrane attack complex triggers an energy dependent process in Gram-negative bacteria that mediates destruction of the inner membrane. This observation in part resulted from the survival of Gram-negative bacteria that were incubated with an uncoupler (DNP) or an inhibitor (KCN) of oxidative phosphorylation during complement activation. In a reexamination of this issue we employed potassium cyanide (KCN) to block energy dependent pathways and observed a dose dependent inhibition of C9 uptake on E. coli J5 during serum incubation, suggesting that cyanide was interfering with complement activation. To verify the effect on complement activation we chose specifically to study the effects of KCN on the C3 convertase of the classical pathway. Sensitized sheep erythrocytes were employed as our model system. This system allowed us to construct a series of stable intermediates that were used to test the effect of cyanide on the formation and activity of precursors of the classical pathway C3 convertase. The data illustrate that the concentrations of potassium cyanide that inhibit complement killing of J5 also inhibit C3 convertase activity on sensitized sheep erythrocytes. The results of this study refute the principal observation made by other investigators, that potassium cyanide protects bacteria from complement killing by inhibiting bacterial energy dependent pathways that spark inner membrane destruction. A better scenario is that the organisms survive because cyanide inhibits complement activation.
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Affiliation(s)
- E F Bloch
- Department of Microbiology, Howard University College of Medicine, Washington, D.C
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26
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Abstract
Embryonic nigral or raphé grafts implanted in the dopamine-depleted neostriatum contain serotonergic neurones and give rise to a serotonergic hyperinnervation of the host striatum. No similar pattern of hyperinnervation is observed in rats with striatal tissue grafts, rats with nigral grafts implanted in the intact striatum, or rats with lesions alone. These observations suggest that striatal dopamine denervation induces some target-derived trophic factors that stimulate fibre growth from serotonergic as well as dopaminergic neurones.
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Affiliation(s)
- A K Wright
- Department of Preclinical Veterinary Sciences, University of Edinburgh, U.K
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McQueen JK, Wright AK, Arbuthnott GW, Fink G. Glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes are increased in the hypothalamus of androgen-insensitive testicular feminized (Tfm) mice. Neurosci Lett 1990; 118:77-81. [PMID: 1701870 DOI: 10.1016/0304-3940(90)90252-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In the hypothalamus of androgen-insensitive testicular feminized (Tfm) mice the normal pattern of immunohistochemical staining for glial fibrillary acidic protein (GFAP) is markedly different from normal. Along the borders of the third ventricle and in the dorsomedial and arcuate nuclei, the numbers of stained astrocytes are increased. The usual ordered array of tanycytic processes is obscured by a tangle of GFAP-stained stellate glial cells. GFAP immunostaining in other regions of the Tfm forebrain is similar to that in normal mice. These results suggest that the distribution of reactive glia in the hypothalamus may have been changed as a consequence of the genetic defect in Tfm mice.
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Affiliation(s)
- J K McQueen
- University Department of Pharmacology, Edinburgh, U.K
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Arbuthnott GW, MacLeod NK, Maxwell DJ, Wright AK. Distribution and synaptic contacts of the cortical terminals arising from neurons in the rat ventromedial thalamic nucleus. Neuroscience 1990; 38:47-60. [PMID: 2175021 DOI: 10.1016/0306-4522(90)90373-c] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Injections of the anterograde tracer Phaseolus vulgaris-leucoagglutinin within the ventromedial thalamic nucleus resulted in many filled fibres in the frontal areas of rat cerebral cortex. The fibres were restricted to the upper part of layer I except in a small area of motor cortex where terminals were also found in deeper layers. Terminals were also seen in the striatum, in parts of the mesencephalic reticular formation and occasionally in the contralateral ventromedial nucleus. There is some topographical order in the projection with medial and dorsal areas well represented in medial cortex while lateral parts of ventromedial nucleus are more directly related to the cortical area that receives the ventrolateral thalamic nucleus projection. Electron microscopic examination showed the terminals in layer I of cortex making synaptic contact with dendritic spines and small dendritic profiles that showed a very dense postsynaptic specialization. Neurons in the ventromedial nucleus could be antidromically driven from electrode positions along strips of cortex which could not be easily related to any known organizational pattern in the cortex. Thalamic neurons responding antidromically to only one stimulation site were more common when the stimulation was within motor cortical areas, suggesting that in this region a more restricted pattern of termination is the rule.
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Affiliation(s)
- G W Arbuthnott
- MRC Brain Metabolism Unit, Department of Pharmacology, Edinburgh, U.K
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Abstract
Anatomical studies in several species have demonstrated a pallidostriatal pathway. We employed electrophysiological and anatomical methods to distinguish the neurones of this pathway from the two pallidocortical groups reported in the rat. Injection of fluorescent retrograde tracers, combined with immunohistochemistry for choline acetyltransferase, provided anatomical evidence of the distinction between neurones of the cholinergic pallidocortical projection and pallidal cells retrogradely labelled from the striatum. Extracellular recordings made in the globus pallidus of halothane-anaesthetised rats provided an electrophysiological description of the pallidostriatal pathway. In some animals neurones of this pathway were distinguished from pallidocortical neurones as a stimulating electrode, situated in the crus cerebri, permitted identification of neurones which projected through this region as well as to the striatum. Neither pallidocortical pathway is reported to have descending axons travelling in the crus cerebri at this point. A preliminary electrophysiological study was carried out in rats in which the dopamine-containing cells of substantia nigra had been destroyed by injections of 6-hydroxydopamine at least 6 months prior to the recording. In the globus pallidus on the lesioned side the mean firing rate of neurones was increased compared with controls. No specific change in firing pattern was noted but the neurones were more responsive to striatal stimulation suggesting that long-term dopamine denervation alters the sensitivity of neurones of globus pallidus.
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Affiliation(s)
- R H Walker
- MRC Brain Metabolism Unit, University Department of Pharmacology, Edinburgh, U.K
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30
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Abstract
Nuclear yellow injections into the striatum of rats led to staining of both neuronal and glial nuclei even after less than 24 h 'transport time'. The distribution of some of the glial nuclei suggested that the dye was being transported along the striato-nigral pathway. Staining in these areas was greatly reduced if kainic acid was co-injected with the Nuclear yellow.
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Abstract
This study of the relationships between cells identified by their catecholamine fluorescence and their less fortunate neighbours became possible with the advent of autoradiographic tracing methods. A major output from the neostriatum returns to the substantia nigra where it fills the pars reticulata. Outputs from this area of substantia nigra are present on both sides of the brain in the thalamus, in parts of parafascicular, intralaminar, and mediodorsal nuclei, and the superior colliculi in the deeper layers. Mainly unilateral pathways reach the ventromedial nucleus of thalamus and also pass under the lateral part of the colliculus to reach the region of the nucleus pendunculo-pontinus among the fibres of the brachium conjunctivum. The roles of those areas in the transmission of the output of the basal ganglia to the motor system of the animal, however, remain obscure.
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Abstract
Subsequent of their achieving stable rates of responding for electrical stimulation through electrodes implanted in the region of the brachium conjunctivum, rats were anaesthetized and 6-hydroxydopamine injected through an implanted guide tube into the area of lateral hypothalamus in which the ascending axons of dopamine-containing neurones are found. The resultant destruction of these axons had similar temporary effects on the behaviour of the animals whether it was ipsilateral or contralateral to the electrode. It is concluded that nigral or mesolimbic dopaminergic systems are not involved in pontine intracranial self-stimulation behaviour.
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Abstract
In animals pretreated with 6-hydroxydopamine, the descending efferent connections of the substantia nigra are restricted to a bilateral projection to the superior colliculus and a pathway which stops in the dorso-lateral reticular formation of the pons.
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Tulloch IF, Arbuthnott GW, Wright AK. Topographical organization of the striatonigral pathway revealed by anterograde and retrograde neuroanatomical tracing techniques. J Anat 1978; 127:425-41. [PMID: 721701 PMCID: PMC1235782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
L-[4,5-3H]leucine was injected stereotaxically into various regions of the rat neostriatum. Light microscopic autoradiographic techniques were used to plot the entire efferent pathways of the neostriatum, and in particular, the projections to the substantia nigra (SN). The terminal distribution of the pathways projecting to the ipsilateral SN was predominantly restricted to the zona reticulata region. The dorsal part of the head of the striatum was found to innervate the anterior and medial portions of the zona reticulata, while the ventral area of the head projected to more posterior regions of the SN. A pathway from the tail of the striatum to the lateral and dorsal parts of SN was also demonstrated. Horseradish peroxidase injections, restricted to different areas of the SN, led to retrograde labelling of neurons in the striatum whose distribution confirmed the topographic organization of the striatonigral pathway demonstrated in the autoradiographic studies.
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Abstract
It proved possible to make lesions which interrupted the striatonigral GABA-containing pathway in the rat brain without causing concomitant damage to the nigrostriatal dopamine containing system. Estimations of striatal concentrations of dopamine (DA), dihydroxyphenyl-acetic acid (DOPAC) and homovanillic acid (HVA) inducated that these lesions had no influence either on normal striatal DA turnover or on the enhancement of DA turnover induced by neuroleptics. Behavioural experiments suggested a motor output function for the striatonigral pathway.
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Hesketh JE, Nicolaou NM, Arbuthnott GW, Wright AK. The effect of chronic lithium administration on dopamine metabolism in rat striatum. Psychopharmacology (Berl) 1978; 56:163-6. [PMID: 25454 DOI: 10.1007/bf00431843] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Striatal dopamine and its metabolites were studied in rats given lithium chloride in the diet. Results showed an increase in homovanillic acid and 3,4-dihydroxyphenylacetic acid levels but no significant change in dopamine concentration after 3 weeks of lithium administration. There was no change in tyrosine hydroxylase activity after 1, 2, and 3 weeks treatment. The results indicate an increase in the release and turnover of dopamine in the lithium-treated animals.
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Wright AK. A proposed model for rhodopsin in photoreceptor membranes. Biophys Struct Mech 1977; 3:31-8. [PMID: 857949 DOI: 10.1007/bf00536451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transient electric birefringence studies have been made on bovine rhodopsin solubilized in the detergent lauryldimethylamine oxide from glutaraldehyde fixed rod outer segment (ROS) membranes. It was found that fixation caused no appreciable differences in the measured relaxation times when compared with unfixed ROS. On the basis of these findings a model for the orientation of rhodopsin in photoreceptor membranes is proposed which accounts for translational diffusion and two modes of rotational diffusion. The proposed model is related to a number of experimentally determined biophysical properties reported in the literature.
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Arbuthnott GW, Mitchell MJ, Tulloch IF, Wright AK. Efferent pathways from lateral hypothalamic neurones [proceedings]. J Physiol 1976; 263:131P-132P. [PMID: 1011099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Arbuthnott GW, Garcia-Munoz M, Nicolaou NM, Tulloch IF, Wright AK. Is the striato-nigral pathway responsible for 'feed-back' control of dopamine release [proceedings]? Br J Pharmacol 1976; 58:272P. [PMID: 974393 PMCID: PMC1667327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Wright AK, Baxter JE. Numerical inversion of the Perrin equations for rotational and translational diffusion constants by iterative techniques. Biophys J 1976; 16:931-8. [PMID: 938731 PMCID: PMC1334918 DOI: 10.1016/s0006-3495(76)85743-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
An iterative numerical technique is presented which allows the semiaxes for prolate and oblate ellipsoids to be determined from the Perrin equations for rotational and translational diffusion constants. The use of this inversion technique is illustrated by application to the proteins: lysozyme, bovine serum albumin, human transferrin, and bovine rhodopsin solubilized in digitonin.
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Williams RC, Ham WT, Wright AK. Ultra high speed electro-optical system for transient birefringence studies of macromolecules in solution. Anal Biochem 1976; 73:52-64. [PMID: 942109 DOI: 10.1016/0003-2697(76)90140-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Abstract
The hydrodynamic method of transient electric birefringence has been used to study bovine rhodopsin solubilized in two detergents, 0.02% Ammonyx LO and 0.045% digitonin. All measurements are interpreted as the sum of two exponentials by which the relaxation times yield the rotary diffusion coefficients for ellipsoids of revolution. The semi-major and minor axes for prolate ellipsoid models have been calculated and their axial ratio, 6.8, in both detergents, is in line with recent reports on the structure of rhodopsin. Studies on bleached rhodopsin showed a large increase in axial ratio in 0.02% Ammonyx LO.
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Abstract
The method of transient electric birefringence has been applied to study the conformation of protein-sodium dodecyl sulfate complexes. A model of a deformable prolate ellipsoid has been proposed for the protein-dodecyl sulfate complex. This model is compared to the models proposed by J. A. Reynolds and C. Tanford (1970), J. Biol. Chem. 245, 5161) and K. Shirahama, K. Tsujii, and T. Takagi (1974, J. Biochem. 75, 309). Differences between these latter two models are resolved by the model presented here. In addition, it has been demonstrated that protein molecular weights may be obtained from the slow relaxation time for transient electric birefringence of protein-dodecyl sulfate complexes.
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Abstract
Birefringence relaxation studies on bovine serum albumin (BSA) reveal transient decay described by a double exponential process. The values of the relaxation times lead to estimation of the size of the equivalent ellipsoid of revolution for BSA. Previous measurements of transient birefringence for BSA have shown a single relaxation process, since the apparatus used in obtaining those data was not fast enough to detect the faster relaxation process.
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Wright AK, Duncan RC, Beekman KA. A numerical inversion of the perrin equations for rotational diffusion constants for ellipsoids of revolution by iterative techniques. Biophys J 1973; 13:795-803. [PMID: 4726879 PMCID: PMC1484328 DOI: 10.1016/s0006-3495(73)86025-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The rotational diffusion coefficients R(1) and R(3) for ellipsoids of revolution are shown to represent another pair of hydrodynamic data to obtain size and shape with theories by Sadron and Scheraga-Mandelkern. An iterative numerical technique is presented which allows the semiaxes to be determined from the Perrin equations for rotational diffusion constants. The use of this inversion technique is illustrated by application to literature data from dielectric dispersion studies.
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