Low cumulative incidence of proliferative retinopathy in childhood-onset type 1 diabetes: a 24-year follow-up study

Short-Term Diabetic Retinopathy Status in People with Type 1 Diabetes Commencing Automated Insulin Delivery

Objective: Rapid improvements in glucose control may lead to early worsening of diabetic retinopathy (EWDR). There is a need to demonstrate safety in people commencing automated insulin delivery (AID) due to the known efficacy in rapid glycemic improvement. We aimed to investigate short-term DR outcomes in people (aged ≥13 years) with type 1 diabetes after initiation of AID (use ≥6 months). Research Design and Methods: Retrospective four center observational study with participants drawn from hospital databases (Dunedin and Christchurch, New Zealand) and also from two research studies based out of Auckland, New Zealand, and Perth, Australia. Demographic and clinical characteristics and DR grading data before and after AID initiation were collected, and statistical analysis was performed. Results: DR grading data from 165 people using AID (three different AID systems) were available, and mean improvement in HbA1c for the total sample was 1.0 ± 1.3 percentage points. Improvements in grading were seen in 32/165 (19%), 99/165 (60%) were stable, and 34/165 (21%) worsened in their R- and/or M-grade. Age at AID initiation ≥18 years was the only significant risk factor for any worsening of DR (P = 0.028). Proliferative change and need for photocoagulation were uncommon but did occur in 3% (5/165); all noted to have prior DR, diabetes duration >10 years, and with at least another diabetes complication or prior DR treatment. Conclusions: In this study, stable or improved DR grades were evident in most who had recently commenced AID. Age at AID initiation <18 years appears protective.

Rates, Risk Factors, and Progression of Diabetic Retinopathy in Children with Type 1 Diabetes: A 15-Year Retrospective Study from a Regional Center in New Zealand

Aims

Diabetic retinopathy (DR) is the primary microvascular complication associated with diabetes. Evidence on DR prevalence among children in New Zealand is scarce. We examined DR rates and associated risk factors in youth with type 1 diabetes (T1D) aged <16 years receiving care from a regional diabetes service in January 2006-December 2020.

Materials and Methods

DR diagnosis followed the International Society for Pediatric and Adolescent Diabetes guidelines. The study included 646 participants; mean age (±SD) at T1D diagnosis was 7.4 ± 3.6 years, 47% were female, and 69% identified as NZ Europeans.

Results

The initial DR screening occurred at a mean age of 12.6 ± 2.4 years and 5.2 ± 2.2 years after T1D diagnosis. At the first DR screen, 23.5% of participants (152/646) were diagnosed with DR: 69.1% (105/152) with minimal, 30.3% (46/152) with mild, and one moderate case (0.7%). Older age at diagnosis (p=0.029) and longer diabetes duration (p=0.015) were predictors of DR at first screen. Patients with at least one positive DR screen had a higher average HbA1c at their first screen (+2.6 mmol/mol; p=0.042). Overall, 55.6% (359/646) of patients had a positive DR screen, whose worst grade was mostly either minimal (58.2%) or mild (40.7%) DR, with only three moderate cases (0.8%) and one severe (0.3%). Children diagnosed with T1D before age 10 were 72% more likely to have DR than older children (p < 0.0001), and DR risk was 32% and 41% higher among Pacific children than NZ European (p=0.008) and Māori (p=0.014) children. Lastly, the only predictor of DR at discharge from paediatric services was HbA1c at the first screen (p < 0.0001).

Conclusions

In this regional cohort of children with T1D, there was a high rate of low-grade DR overall and at first retinal screen, with an increasing rate until transfer to adult services. Our findings underscore the importance of ongoing DR screening, reducing glycaemic levels, and supporting vulnerable high-risk groups.

Prognostic factors for the development and progression of proliferative diabetic retinopathy in people with diabetic retinopathy

BACKGROUND

Diabetic retinopathy (DR) is characterised by neurovascular degeneration as a result of chronic hyperglycaemia. Proliferative diabetic retinopathy (PDR) is the most serious complication of DR and can lead to total (central and peripheral) visual loss. PDR is characterised by the presence of abnormal new blood vessels, so-called "new vessels," at the optic disc (NVD) or elsewhere in the retina (NVE). PDR can progress to high-risk characteristics (HRC) PDR (HRC-PDR), which is defined by the presence of NVD more than one-fourth to one-third disc area in size plus vitreous haemorrhage or pre-retinal haemorrhage, or vitreous haemorrhage or pre-retinal haemorrhage obscuring more than one disc area. In severe cases, fibrovascular membranes grow over the retinal surface and tractional retinal detachment with sight loss can occur, despite treatment. Although most, if not all, individuals with diabetes will develop DR if they live long enough, only some progress to the sight-threatening PDR stage.  OBJECTIVES: To determine risk factors for the development of PDR and HRC-PDR in people with diabetes and DR.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 5), Ovid MEDLINE, and Ovid Embase. The date of the search was 27 May 2022. Additionally, the search was supplemented by screening reference lists of eligible articles. There were no restrictions to language or year of publication.  SELECTION CRITERIA: We included prospective or retrospective cohort studies and case-control longitudinal studies evaluating prognostic factors for the development and progression of PDR, in people who have not had previous treatment for DR. The target population consisted of adults (≥18 years of age) of any gender, sexual orientation, ethnicity, socioeconomic status, and geographical location, with non-proliferative diabetic retinopathy (NPDR) or PDR with less than HRC-PDR, diagnosed as per standard clinical practice. Two review authors independently screened titles and abstracts, and full-text articles, to determine eligibility; discrepancies were resolved through discussion. We considered prognostic factors measured at baseline and any other time points during the study and in any clinical setting. Outcomes were evaluated at three and eight years (± two years) or lifelong.  DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data from included studies using a data extraction form that we developed and piloted prior to the data collection stage. We resolved any discrepancies through discussion. We used the Quality in Prognosis Studies (QUIPS) tool to assess risk of bias. We conducted meta-analyses in clinically relevant groups using a random-effects approach. We reported hazard ratios (HR), odds ratios (OR), and risk ratios (RR) separately for each available prognostic factor and outcome, stratified by different time points. Where possible, we meta-analysed adjusted prognostic factors. We evaluated the certainty of the evidence with an adapted version of the GRADE framework.   MAIN RESULTS: We screened 6391 records. From these, we identified 59 studies (87 articles) as eligible for inclusion. Thirty-five were prospective cohort studies, 22 were retrospective studies, 18 of which were cohort and six were based on data from electronic registers, and two were retrospective case-control studies. Twenty-three studies evaluated participants with type 1 diabetes (T1D), 19 with type 2 diabetes (T2D), and 17 included mixed populations (T1D and T2D). Studies on T1D included between 39 and 3250 participants at baseline, followed up for one to 45 years. Studies on T2D included between 100 and 71,817 participants at baseline, followed up for one to 20 years. The studies on mixed populations of T1D and T2D ranged from 76 to 32,553 participants at baseline, followed up for four to 25 years.  We found evidence indicating that higher glycated haemoglobin (haemoglobin A1c (HbA1c)) levels (adjusted OR ranged from 1.11 (95% confidence interval (CI) 0.93 to 1.32) to 2.10 (95% CI 1.64 to 2.69) and more advanced stages of retinopathy (adjusted OR ranged from 1.38 (95% CI 1.29 to 1.48) to 12.40 (95% CI 5.31 to 28.98) are independent risk factors for the development of PDR in people with T1D and T2D. We rated the evidence for these factors as of moderate certainty because of moderate to high risk of bias in the studies.  There was also some evidence suggesting several markers for renal disease (for example, nephropathy (adjusted OR ranged from 1.58 (95% CI not reported) to 2.68 (2.09 to 3.42), and creatinine (adjusted meta-analysis HR 1.61 (95% CI 0.77 to 3.36)), and, in people with T1D, age at diagnosis of diabetes (< 12 years of age) (standardised regression estimate 1.62, 95% CI 1.06 to 2.48), increased triglyceride levels (adjusted RR 1.55, 95% CI 1.06 to 1.95), and larger retinal venular diameters (RR 4.28, 95% CI 1.50 to 12.19) may increase the risk of progression to PDR. The certainty of evidence for these factors, however, was low to very low, due to risk of bias in the included studies, inconsistency (lack of studies preventing the grading of consistency or variable outcomes), and imprecision (wide CIs). There was no substantial and consistent evidence to support duration of diabetes, systolic or diastolic blood pressure, total cholesterol, low- (LDL) and high- (HDL) density lipoproteins, gender, ethnicity, body mass index (BMI), socioeconomic status, or tobacco and alcohol consumption as being associated with incidence of PDR. There was insufficient evidence to evaluate prognostic factors associated with progression of PDR to HRC-PDR.  AUTHORS' CONCLUSIONS: Increased HbA1c is likely to be associated with progression to PDR; therefore, maintaining adequate glucose control throughout life, irrespective of stage of DR severity, may help to prevent progression to PDR and risk of its sight-threatening complications. Renal impairment in people with T1D or T2D, as well as younger age at diagnosis of diabetes mellitus (DM), increased triglyceride levels, and increased retinal venular diameters in people with T1D may also be associated with increased risk of progression to PDR. Given that more advanced DR severity is associated with higher risk of progression to PDR, the earlier the disease is identified, and the above systemic risk factors are controlled, the greater the chance of reducing the risk of PDR and saving sight.

Diabetic retinopathy and visual impairment in a Norwegian diabetic coast population with a high dietary intake of fish oils. An observational study

PURPOSE

To present retinal and visual findings in a Norwegian west coast diabetic population and to elucidate the effect of dietary intake of marine polyunsaturated fatty acids (PUFAs) on the development of diabetic retinopathy (DR).

METHODS

In an eye practice in an archipelago of 314 km², serving a population of about 40 000, we recorded the prevalence of visual impairment and DR in a referred diabetic population. 510 consecutive patients were included, 238 females and 272 males. 50 patients had type I and 460 had type II diabetes mellitus (DM). Self-reported medication, diet supplements, HbA1c and fish consumption were registered.

RESULTS

In the type I group, the median age was 44.5 and median DM duration 11.5 years [1-44]. 48% had photographic evidence of DR, 8 patients (16%) had proliferative retinopathy (PDR), and 6 patients (12%) had diabetic macular oedema (DME). All had best-corrected visual acuity (BCVA) of 0.5 (log MAR 0.3) or better in the best eye. In the type II group, the median DM duration was 8 years [1-53], and median age was 66. 98% had best eye BCVA at or better than 0.5 (log MAR 0.3) in the best eye.

CONCLUSION

None of the 510 patients had BCVA worse than 0.3 (log MAR 0.48) due to diabetic retinopathy. Compared to similar studies, we found a very low visual impairment rate. A possible protective effect of PUFA on the prevalence and progression of diabetic microangiopathy including retinopathy is discussed.

Serum Galectin-3 and Subsequent Risk of Coronary Heart Disease in Subjects With Childhood-Onset Type 1 Diabetes: A Cohort Study

OBJECTIVE

To study whether serum galectin-3 and other biomarkers of inflammation predict coronary heart disease (CHD) in subjects with long-standing childhood-onset type 1 diabetes.

RESEARCH DESIGN AND METHODS

A population-based nationwide cohort of 299 subjects with type 1 diabetes diagnosed in Norway at <15 years of age during 1973-1982 was examined in 2002-2003 at a mean age of 33 years (range 21-44), with mean diabetes duration of 24 years (range 19-30). Subjects were followed through 31 December 2017 for their first CHD event registered by a hospitalization or cause of death using nationwide registries. Stored serum samples were available for 296 subjects and analyzed for interleukin-6 (IL-6), IL-6 receptor, IL-18, hs-CRP, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), galectin-3, and high-sensitivity troponin T. Adjusted hazard ratios (aHRs) for CHD per SD increase in biomarker were estimated using Cox regression.

RESULTS

Of 295 subjects, 40 (13.6%) had a documented CHD event during a mean follow-up of 14.4 years (range 0.5-16). IL-6 (aHR 1.32 [95% CI 1.07-1.63]), galectin-3 (aHR 1.44 [95% CI 1.09-1.80]), and TIMP-1 (aHR 1.37 [95% CI 1.04-1.81]) were significant predictors of CHD after adjustment for conventional risk factors.

CONCLUSIONS

Galectin-3 was significantly associated with future CHD in subjects with type 1 diabetes, and if the results are replicated in larger studies, it may aid in prediction together with conventional risk factors for CHD.

Morbidity and Complications of Diabetes Mellitus in Children and Adolescents in Ghana: Protocol for a Longitudinal Study

Background

Diabetes is associated with premature morbidity and mortality from its many complications. There are limited data on the chronic complications of diabetes in children and adolescents in sub-Saharan Africa.

Objective

The study aims to determine the (1) burden and related factors of chronic systemic complications of diabetes, including diabetic and nondiabetic ocular conditions in children and adolescents, and (2) quality of life (QoL) of participants compared to healthy controls. This manuscript describes the study methodology.

Methods

Demographic information, medical history, anthropometric measurements, and laboratory characteristics were collected, and the participants were screened for microvascular and macrovascular complications as well as nondiabetic ocular disease. QoL questionnaires were administered to participants, their caregivers, and controls. Participants were followed up annually up to 3 years to determine the natural history of and trends in these conditions. SPSS Version 25.0 will be used for data analysis. Continuous and categorical data will be presented as mean (SD) and as percentages (%), respectively. t tests and analysis of variance will be used to compare means, and chi-square tests will be used to compare categorical data. Correlation, regression, and logistic regression analyses will be employed to establish linear associations and causal associations as appropriate. Relative risk and odds ratios will be used to estimate risk. QoL outcomes in Ghanaian children and adolescents with diabetes mellitus compared with caregivers and healthy controls will be assessed using the Pediatric Quality of Life inventory. Significance will be set at α=.05.

Results

Institutional approval from the Ethical and Protocol Review Committee of the University of Ghana Medical School was received on August 22, 2014 (Protocol Identification Number: MS-Et/M.12-P4.5/2013-2014). Funding for the project was received from the University of Ghana Research Fund (#UGRF/9/LMG-013/2015-2016) in March 2016. Patient recruitment, clinical examination, and data collection commenced in August 2016 and was completed in September 2019. A total of 58 children and adolescents with diabetes mellitus have been recruited. Blood samples were stored at –80 °C for analysis, which was completed at the end of July 2020. Data analysis is ongoing and will be completed by the end of December 2020. Investigators plan to submit the results for publication by the end of February 2021.

Conclusions

The prevalence, natural history, trends in diabetic complications and nondiabetic ocular disease, and QoL will be provided. Our data may inform policies and interventions to improve care given to children and adolescents with diabetes.

International Registered Report Identifier (IRRID)

DERR1-10.2196/21440

Foveal avascular zone area analysis in juvenile-onset type 1 diabetes using optical coherence tomography angiography

PURPOSE

Optical coherence tomography angiography (OCTA) was performed on patients with juvenile-onset type 1 diabetes (T1DM) but with no diabetic retinopathy to measure the foveal avascular zone (FAZ) area.

STUDY DESIGN

Retrospective single-facility study METHODS: Twenty-nine patients (58 eyes) with juvenile-onset T1DM were studied. Images (3 mm x 3 mm cube centered on the fovea) were acquired using an OCTA device. Age at examination was 16.1 ± 8.7 years; onset age was 6.4 ± 3.5 years; duration of diabetes was 9.7 ± 8.3 years. Twenty-four age-matched healthy individuals were studied as controls.

RESULTS

FAZ area was significantly larger in T1DM patients than in controls (0.29 ± 0.09 vs. 0.25 ± 0.08 mm², P = 0.0234). Parafoveal vessel density was not significantly different between patients and controls (50.43 ± 4.24 vs. 50.07 ± 4.64, P = 0.8842). By generalized linear model analysis, annual HbA1c (P = 0.0190), number of serious hypoglycemic attacks (P = 0.0210), and onset age (P = 0.0447) were identified as variables significantly associated with FAZ area. Age, gender, duration of disease, total cholesterol, high or low-density lipoprotein, triglycerides, and body mass index were not significantly associated with FAZ area.

CONCLUSION

Patients with juvenile-onset T1DM and no diabetic retinopathy had increased FAZ, but no significant difference in parafoveal vessel density compared to healthy controls. Larger FAZ area was associated with higher annual HbA1c, more episodes of severe hypoglycemic attacks, and older onset age.

Diabetic ketoacidosis at diagnosis of type 1 diabetes and glycemic control over time: The SEARCH for diabetes in youth study

BACKGROUND

The diagnosis of type 1 diabetes (T1D) in youth is often associated with diabetic ketoacidosis (DKA). We aimed to evaluate if the presence of DKA at diagnosis of T1D is associated with less favorable hemoglobin A1c (HbA1c) trajectories over time.

METHODS

The SEARCH for Diabetes in Youth study of 1396 youth aged <20 years with newly diagnosed T1D were followed for up to 13 (median 8 [interquartile range or IQR 6-9]) years after diagnosis. Of these, 397 (28%) had DKA (bicarbonate level < 15 mmol/L and/or pH < 7.25 (venous) or < 7.30 (arterial or capillary) or mention of DKA in medical records) at diabetes onset. Longitudinal HbA1c levels were measured at each follow-up visit (average number of HbA1c measures 3.4). A linear piecewise mixed effects model was used to analyze the effect of DKA status at diagnosis of T1D on long-term glycemic control, adjusting for age at diagnosis, diabetes duration at baseline, sex, race/ethnicity, household income, health insurance status, time-varying insulin regimen and glucose self-monitoring, study site, and baseline fasting C-peptide level.

RESULTS

At baseline, HbA1c levels were significantly higher in youth with T1D diagnosed in DKA vs those who were not (9.9% ± 1.5% vs 8.5% ± 1.4%, respectively). After the first year with diabetes, there was a significant difference in the rate of change in HbA1c levels by DKA status: HbA1c was 0.16% higher each year in youth with DKA compared to those without (interaction P-value<0.0001), after adjusting for aforementioned covariates.

CONCLUSIONS

DKA at T1D diagnosis is associated with worsening glycemic control over time, independent of demographic, socioeconomic, and treatment-related factors and baseline fasting C-peptide.

Diabetic retinopathy in type 1 diabetes patients in Western Norway

PURPOSE

To describe the prevalence of diabetic retinopathy (DR), associated risk factors and health-related quality of life (HRQoL) in a population-based cohort of patients with type 1 diabetes mellitus (DM1).

METHODS

All patients underwent a general and ophthalmic examination including seven-field stereo fundus photography for grading of DR and diabetic macular oedema (DMO). Kaplan-Meier survival analyses were performed to evaluate disease progression in relation to diabetes duration, age and year of diabetes onset. HRQoL and its association with DR were assessed by the Medical Outcomes Study Short Form 36 (SF-36) questionnaire.

RESULTS

A total of 237 DM1 patients were included. Mean age at inclusion was 34 years (range, 4-75 years), and mean diabetes duration was 19 years (range, 5 months-63 years). A total of 145 patients (61%) had DR. Sixty-two patients (26%) had mild, 39 (16%) moderate and 13 (5%) severe nonproliferative DR, while 31 (13%) had proliferative DR. The prevalence of DMO was 8%. The most important risk factors predicting severity of DR were diabetes duration (p < 0.0001) and HbA1c level (p < 0.0001). Neuropathy (p = 0.006), nephropathy (p = 0.004) and male gender (p = 0.02) were also significant predictors of DR. Compared to normative SF-36 data, there was a linear trend of decreasing HRQoL with increasing severity of DR that was statistically significant for the four physical dimension scores.

CONCLUSION

The prevalence of DR in DM1 was largely within the range of previous reports. Diabetes duration, HbA1c level, neuropathy, nephropathy and male gender were all significant predictors of DR severity. The patients with more severe DR had lower HRQoL.

Glycemic control and complications in patients with type 1 diabetes - a registry-based longitudinal study of adolescents and young adults

OBJECTIVE

The main aims of this study were to assess longitudinal glycemic control and the prevalence of retinopathy and nephropathy in young people (aged 14-30 yr) with type 1 diabetes in Norway.

METHOD

Data on 874 patients were obtained by linking two nationwide, population-based medical quality registries: The Norwegian Diabetes Register for Adults and The Norwegian Childhood Diabetes Registry.

RESULTS

Median age was 23 yr, median diabetes duration 9 yr and 51% were male. Median HbA_1c increased through adolescence to peak at ages of 17 yr for females and 19 yr for males, females had higher HbA_1c than males: 9.3% (78 mmol/mol) vs. 9.1% (76 mmol/mol). Subsequently, median HbA_1c declined but was still >8% (>64 mmol/mol) for patients approaching 30 yr. Half of the patients aged 14-17 yr and 40% of patients aged 18-25 yr had HbA_1c >9% (75 mmol/mol). Retinopathy was found in 16% and nephropathy in 13% of the population. Patients transferring from the pediatric department to adult care between the ages of 14 and 17 yr had higher median HbA_1c and prevalence of late complications than those transferring at ages 18-22 yr. Less than 40% of patients with albuminuria were treated with ACE inhibitors or angiotensin II receptor blocker.

CONCLUSION

Our results demonstrate that treatment of adolescents and young adults with type 1 diabetes in Norway is not optimal, especially for patients in their late teens. We suggest that pediatricians and endocrinologists should critically assess the care offered to this group and consider new approaches to help them improve glycemic control.

Prevalence and risk factors for diabetic retinopathy in a hospital-based population of Australian children and adolescents with type 1 diabetes

BACKGROUND

The aim of this study was to investigate the prevalence of, and traditional and emerging risk factors associated with, retinopathy in a hospital-based population of Australian children and adolescents with type 1 diabetes.

METHODS

This was a cross-sectional study of 483 children and adolescents with type 1 diabetes. Medical files were audited to collect all relevant clinical data. Diabetic retinopathy was assessed from colour retinal images by an ophthalmologist.

RESULTS

Diabetic retinopathy was observed in 11 (2.3%) participants. Logistic regression revealed that the principal components analysis derived risk profile of: higher serum creatinine, older age, higher systolic blood pressures, higher body mass index, abnormal estimated glomerular filtration rate (eGFR) (<59 mL/min), lower high density lipoproteins (HDL) cholesterol, higher serum sodium, longer duration of diabetes and narrower retinal arteriolar calibre was associated with diabetic retinopathy (ExpB=2.60, 95% CI 1.36/4.96, p=0.004).

CONCLUSIONS

These results support the concept that the pathogenesis of diabetic retinopathy is likely due to the combined influence of various risk factors, many already identified.

Natural history of retinopathy in children and young people with type 1 diabetes

PurposeTo describe the prevalence and natural history of retinopathy in a cohort of children and young people with type 1 diabetes attending a tertiary hospital diabetes clinic.MethodsWe analysed retinopathy screening data from 2008 to 2010 on all eligible children using the 'Twinkle' diabetes database and the regional retinal screening database.ResultsA total of 88% (149/169) of eligible children were screened in 2008, median age 14 years, 52% male. The prevalence of retinopathy was 19.5% (30/149). All children had background retinopathy grade R1. There was significant difference in median (range) duration of diabetes, 7.7 years (0.6-13.7) vs 5 years (0.2-12.5) (P<0.001) and median (range) HbA1C, 9.1% (7.2-14) vs 8.6% (5.6-13.1) (P=0.02), between the groups with and without retinopathy. At 2- years follow-up, 12/30 (40%) had unchanged retinopathy grade R1, 10/30 (33.3%) showed resolution of changes (R0), 1/30 progressed to maculopathy, and 7/30 had no follow-up data. Median (range) HbA1C in 2008 and 2010 for the groups with stable vs resolved changes was similar, 9.1% (7.2-14.0) and 9.2% (7-14.0) vs 9.5% (7.8-14.0) and 9.2% (8.7-14.0). Of the 119 without retinopathy in 2008, 27 (22.5%) had developed retinopathy within 2 years, including 1 with pre-proliferative retinopathy and 1 with maculopathy. There was no significant difference in HbA1c between those who progressed to retinopathy (8.7% (7.1-13.1)) (8.7% (7.1-13.1)), and those who did not (8.6% (6.3-12.2)).ConclusionsPrevalence of background retinopathy in our cohort was comparable to the previously published reports, with higher HbA1c and longer duration of diabetes being significant risk factors. On short-term follow-up, Grade 1 retinopathy is likely to resolve in a third of patients and remain unchanged in just over a third.

Adolescents with Type 1 Diabetes--The Impact of Gender, Age, and Health-Related Functioning on Eating Disorder Psychopathology

Objective

To investigate correlates of eating disorder psychopathology in adolescent males and females with type 1 diabetes.

Method

A total of 105 adolescents with type 1 diabetes (42% males), aged 12–20 years, were recruited from the Norwegian Childhood Diabetes Registry in this population-based study. All participants were interviewed with the Child Eating Disorder Examination. Additionally, the Brief Illness Perception Questionnaire, the Adolescent Coping Orientation for Problem Experiences and the Beliefs about Medicines Questionnaire were administered to assess health-related functioning. Clinical data were obtained from the Norwegian Childhood Diabetes Registry.

Results

Significant gender differences were demonstrated in the pattern of correlates of eating disorder pathology. Among females, eating disorder psychopathology was significantly associated with body mass index adjusted for age and gender, age, insulin restriction, coping, illness perceptions, and perceptions of insulin concern. In a regression model, age, illness perceptions, and insulin restriction remained significantly associated with eating disorder psychopathology, explaining 48% of the variance. None of the variables were associated with eating disorder psychopathology among males.

Discussion

Greater clinical awareness of illness perceptions, attitudes toward insulin, and insulin restriction may potentially decrease the risk of developing eating disorders among female adolescents with type 1 diabetes, and the subsequent increased morbidity and mortality associated with comorbid type 1 diabetes and eating disorders.

Long-term Outcomes in Youths with Diabetes Mellitus

In this article, the author reviews the long-term outcomes and their precursors of type 1 diabetes starting in youth. The author also contrasts the changing incidence of these long-term complications as we have moved from the pre-Diabetes Control and Complications Trial (DCCT) to the post-DCCT standard of care and reviews the emerging data related to complications in youths with type 2 diabetes. Finally, the author reviews the recent understanding related to the effects of diabetes on the brain and cognition.

Early risk stratification in pediatric type 1 diabetes

In the late 1980s all Danish children with type 1 diabetes were invited for a nationwide evaluation of glycemic control. Approximately 75% (n = 720) participated and have later been referred to as The Danish Cohort of Pediatric Diabetes 1987 (DCPD1987). The results were surprisingly poor glycemic control among these young patients which lead to a great emphasis on glycemic control in the Danish Pediatric Departments. In 1995 the participants were invited for yet another evaluation but this time with main focus on early signs of microvascular complications - 339 participated. The mean HbA1c had remained at high levels (9.6%) and 60% of the participants had some level of Diabetic Retinopathy (DR). However, as the patients with DR mostly had the very milder forms it was believed that stricter glycemic control would reverse or at least stop progression of the disease in accordance with results from the large intervention study DCCT. This was investigated further at follow-up in 2011. The first study in the present thesis aimed to describe the 16-year incidence, progression and regression of DR in 185 participants from the DCPD1987 cohort. The 16-year incidence of proliferative retinopathy (PDR), 2-step progression and regression of DR was 31.0, 64.4, and 0.0%, respectively. As expected, the participants with PDR at follow-up had significantly higher HbA1c-values at both baseline and follow-up than those without PDR. However; a significantly larger decrease in HbA1c was also observed in the group with PDR over the study period, which in accordance with DCCT should have prevented the development of PDR to some extent. A surprisingly high incidence of proliferative retinopathy amongst young patients with type 1 diabetes in Denmark was found despite improvements in HbA1c over time. The improvement in HbA1c was either too small or happened too late. This study highlights that sight-threatening diabetic retinopathy remain a major concern in type 1 diabetes and the importance of early glycemic control. Identifying high-risk patients at a very early stage is not only desired for prevention of diabetic retinopathy - neuropathy and nephropathy similarly remain frequent in type 1 diabetes. Early risk stratification will allow for timely implementation of effective interventions and for individualized screening and diabetes care. The second and third studies of this thesis provide the longest prospective studies to date on both retinal vessel calibers and retinal fractal dimensions and their predictive value on diabetic microvascular complications. Semi-automated computer software has been developed to measure smaller changes in the retinal vessels on retinal photographs. Two of the first parameters to be reliably estimated by these programs were retinal vessel calibers and retinal vascular fractal dimensions (a quantitative measure on vascular complexity). There is very limited knowledge on their predictive value on diabetic complications thus far. In the second and third study, a consistent relation between narrower retinal arteriolar calibers, wider retinal venular calibers, lower fractal dimensions and the 16-year incidences of diabetic neuropathy, nephropathy and proliferative retinopathy was found. This has never been shown before. The results on vessel analyzes provides indications of a common pathogenic pathway for diabetic microvascular complications and therefore a possibility of universal risk estimation for development of neuropathy, nephropathy and retinopathy in type 1 diabetes.

Equal access to health care may diminish the differences in outcome between native and immigrant patients with type 1 diabetes

BACKGROUND/OBJECTIVE

Previous studies have found that ethnicity influences glycemic control. We hypothesized that differences between Nordic and non-Nordic patients are less pronounced for children with type 1 diabetes in high incidence countries in Northern Europe.

RESEARCH DESIGN AND METHODS

We investigated patients aged 0-15 yr in national pediatric registers in Denmark (D), Iceland (I), Norway (N), and Sweden (S) (2006-2009). Ethnic origin was defined by maternal country of birth as being Nordic or non-Nordic (other countries).

RESULTS

The cohort (n = 11,908, 53.0% boys, onset age 7.7 (3.9) yr, diabetes duration 6.1 (3.6) yr, [mean, (SD)]) comprised 921 (7.7%) non-Nordic patients. The frequencies of non-Nordic patients according to country of residence were: 5.7% (D), 2.7% (I), 5.5% (N), and 9.4% (S). Sex distribution and BMI z-score did not differ between Nordic and non-Nordic patients, but non-Nordic patients were 0.5 yr younger at onset than Nordic patients (p < 0.0006). Non-Nordic patients had a lower number of daily insulin bolus injections and higher daily insulin doses compared to their Nordic peers. Patients of non-Nordic origin had slightly higher HbA1c levels (0.6-2.9 mmol/mol, p < 0.001) and, with the exception of Norway, were less frequently treated with CSII (p = 0.002) after adjusting for confounders.

CONCLUSIONS

The reported differences in glycemic regulation between Nordic and non-Nordic type 1 diabetes children and adolescents in four Nordic countries are diminutive, but persist after accounting for treatment intensity.

Pediatric Diabetes Consortium Type 1 Diabetes New Onset (NeOn) Study: factors associated with HbA1c levels one year after diagnosis

OBJECTIVE

To identify determinants of hemoglobin A1c (HbA1c) levels 1 yr after the diagnosis of type 1 diabetes (T1D) in participants in the Pediatric Diabetes Consortium (PDC) T1D New Onset (NeOn) Study.

RESEARCH DESIGN AND METHODS

Diabetes-specific as well as socioeconomic factors during the first year following diagnosis were analyzed in 857 participants (mean age 9.1 yrs, 51% female, 66% non-Hispanic White) not participating in an intervention study who had an HbA1c value at 12 months.

RESULT

Mean ± SD HbA1c at 1 yr was 62 ± 16 mmol/mol (7.8% ± 1.5). In univariate and multivariate analyses, clinical center, non-Hispanic White race, private health insurance, living with both parents, higher frequency of self-monitoring of blood glucose (SMBG), and lower insulin requirements were associated with lower HbA1c concentrations at 1 yr (p < 0.01). No association was found with gender, age, Tanner stage, body mass index (BMI), diabetic ketoacidosis (DKA) at onset, number of positive autoantibodies or HbA1c at onset, or number of visits to diabetes physician during the first year.

CONCLUSIONS

White race, higher socioeconomic status, two-parent household, more frequent SMBG, and low insulin requirements are associated with lower HbA1c concentration 1 yr after the onset of T1D in children.

Current trends in the monitoring and treatment of diabetic retinopathy in young adults

The diagnosis and treatment of diabetic retinopathy (DR) in young adults have significantly improved in recent years. Research methods have widened significantly, for example, by introducing spectral optical tomography of the eye. Invasive diagnostics, for example, fluorescein angiography, are done less frequently. The early introduction of an insulin pump to improve the administration of insulin is likely to delay the development of diabetic retinopathy, which is particularly important for young patients with type 1 diabetes mellitus (T1DM). The first years of diabetes occurring during childhood and youth are the most appropriate to introduce proper therapeutic intervention before any irreversible changes in the eyes appear. The treatment of DR includes increased metabolic control, laserotherapy, pharmacological treatment (antiangiogenic and anti-inflammatory treatment, enzymatic vitreolysis, and intravitreal injections), and surgery. This paper summarizes the up-to-date developments in the diagnostics and treatment of DR. In the literature search, authors used online databases, PubMed, and clinitrials.gov and browsed through individual ophthalmology journals, books, and leading pharmaceutical company websites.

The 16-year incidence, progression and regression of diabetic retinopathy in a young population-based Danish cohort with type 1 diabetes mellitus: The Danish cohort of pediatric diabetes 1987 (DCPD1987)

The aim was to investigate the long-term incidence of proliferative diabetic retinopathy (PDR), and progression and regression of diabetic retinopathy (DR) and associated risk factors in young Danish patients with Type 1 diabetes mellitus. In 1987-89, a pediatric cohort involving approximately 75 % of all children with Type 1 diabetes in Denmark <19 years of age was identified (n = 720). In 1995, 339 (47.1 %) were re-studied with retinopathy graded and all relevant diabetic parameters assessed. Of those, 185 (54.6 %) were evaluated again in 2011 for the same clinical parameters. All retinal images were graded using modified early treatment of DR study for 1995 and 2011. In 1995, mean age was 21.0 years and mean diabetes duration 13.5 years. The 16-year incidence of proliferative retinopathy, 2-step progression and 2-step regression of DR was 31.0, 64.4 and 0.0 %, respectively, while the incidence of DR was 95.1 %. In a multivariate logistic regression model, progression to PDR was significantly associated with 1995 HbA1c (OR 2.61 per 1 % increase, 95 % CI 1.85-3.68) and 1995 diastolic blood pressure (OR 1.79 per 10 mmHg increase, 95 % CI 1.04-3.07). Two-step progression of DR was associated with male gender (OR 2.37 vs. female, 95 % CI 1.07-5.27), 1995 HbA1c (OR 3.02 per 1 % increase, 95 % CI 2.04-4.48) and 1995 vibration perception threshold (OR 1.19 per 1 Volt increase, 95 % CI 1.02-1.40). In conclusion, one in three progressed to PDR and two in three had 2-step progression despite young age and increased awareness of the importance of metabolic control. After 30 years duration of diabetes, the presence of DR is almost universal.

Assessing progress in retinopathy outcomes in type 1 diabetes: comparing findings from the Wisconsin Diabetes Registry Study and the Wisconsin Epidemiologic Study of Diabetic Retinopathy

OBJECTIVE

The Wisconsin Diabetes Registry Study (WDRS) cohort consisted of patients diagnosed with type 1 diabetes in the same geographic region as, but 8-34 years later than the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) cohort, providing a unique opportunity to assess changes in complications. We estimated the current prevalence and severity of diabetic retinopathy at 20 years of diabetes duration, compared these between eras, and evaluated the influence of diabetes management.

RESEARCH DESIGN AND METHODS

Twenty-year examinations, including fundus photographs, were completed on 305 WDRS subjects during 2007-2011. A subgroup of the WESDR cohort participated in one of four study visits during 1980-1996, at similar diabetes duration (n = 583). Adjusted ordinal logistic regression with three retinopathy severity categories was used to estimate odds ratios (ORs) of more severe retinopathy with diagnosis during an earlier era.

RESULTS

Mean hemoglobin A(1c) (HbA(1c)) was lower in WDRS than in WESDR (8.0% vs. 9.3% [P < 0.001], and 93.4% vs. 21.3% [P < 0.001]) used ≥3 daily insulin injections or an insulin pump. In WDRS, 18% had vision-threatening levels of retinopathy vs. 43% in WESDR. The adjusted OR of more severe retinopathy in the earlier era (OR 3.0 [95% CI 2.2-4.0]) was reduced by including 20-year HbA(1c) in the model (OR 2.2 [1.6-3.0]).

CONCLUSIONS

Retinopathy severity at a diabetes duration of 20 years is lower in the more recent era of type 1 diabetes. Updated projections should be used when informing newly diagnosed individuals of prognosis and for health care cost assessments. Current glycemic control explained a limited amount of the difference.

Glyoxalase 1 enzyme activity in erythrocytes and Ala111Glu polymorphism in type 1-diabetes patients

AIMS/HYPOTHESIS

The enzyme glyoxalase 1 (GLO1) can inactivate the glycoxidation product methylglyoxal that is thought to be an important contributor to the pathogenesis of vascular complications in diabetes. We aimed to study erythrocyte GLO1 activity and whether the Ala111Glu GLO1 gene polymorphism affected GLO1 activity.

METHODS

Fasting erythrocyte GLO1 activity was measured spectrophotometrically. The A111G gene polymorphism, assessed in DNA from leucocytes was analyzed in patients with type 1-diabetes and normal kidney function and compared with a control group.

RESULTS

Sixty-one patients with type 1-diabetes duration of 26.1 (10.7) years, mean (SD) with a HbA1c of 7.8 (0.9)%, 61.7 (9.9) mmol/mol and normal glomerular filtration rate were compared with 62 age- and sex-matched healthy controls. GLO1 activity was 0.206 (0.183-0.231) median (25-75% percentiles) U/mg Hb in the control group vs. 0.192 (0.165-0.224) in the diabetes group, (p = 0.149). In the diabetes group GLO1 correlated with HbA1c (r = 0.33, p < 0.01) and oxidized glutathione (GSSG) (r = - 0.34, p < 0.01) and in the control group with GSH (r = 0.37, p < 0.005) and fasting glucose (r = 0.26, p < 0.04). In a multiple regression analysis with GLO1 activity as the dependent variable, including the Ala111Glu polymorphism, the significant independent variables were log GSSG (ß - 0.318, p = 0.02) and HbA1c (ß 0.285, p = 0.041) in the diabetes group and log GSH, (ß 0.407, p = 0.004) in the control group.

CONCLUSIONS/INTERPRETATION

Erythrocyte glyoxalase 1 activity did not differ between patients with type 1-diabetes and controls. The Ala111Glu glyoxalase gene polymorphism did not have an effect on glyoxalase 1 activity in either group.

Retinopathy and visual impairment in diabetes, impaired glucose tolerance and normal glucose tolerance: the Nord-Trøndelag Health Study (the HUNT study)

PURPOSE

The aim of the study was to describe the prevalence of visual impairment and retinopathy and to investigate risk factors for retinopathy in persons with diabetes, screen-detected diabetes, impaired glucose tolerance and normal glucose tolerance in a subpopulation of the HUNT study.

METHODS

We used a sample (n = 163) from a population-based screening survey of hyperglycaemia, undertaken in 2004-2005 in Verdal, Norway. Baseline information was accessible through the second Nord-Trøndelag Health Study (HUNT2), 1995-97. Data collection was made in 2005 and included patient history, refraction, visual acuity, cataract assessment and single-field, nonmydriatic retinal photography. Retinal photographs were graded independently by two graders blinded to patient information. Data were analysed with standard statistical methods, and p < 0.05 was considered significant.

RESULTS

In all, 126 (77%) persons participated, 55% were women. The mean (SD) age was 59 (± 14) years. Four (3%) had correctable visual impairment, and none were visually impaired. Retinal photographs were gradable for both eyes in 109 (87%) participants. The prevalence of retinopathy was 11% in persons with known diabetes, 4% in persons with screen-detected diabetes, 3% in persons with impaired glucose tolerance and 10% in persons with normal glucose tolerance. Retinopathy was not associated with known history of diabetes or current glycaemic status. Nonfasting plasma glucose (in 1995-97) was an independent risk factor for retinopathy (in 2005), OR (95% CI) 1.5 (1.01, 2.13), p = 0.046.

CONCLUSION

The prevalence of diabetic retinopathy in persons with diabetes in this study was low. Appropriate optical correction and regular eye examination can prevent unnecessary visual impairment in both persons with and without diabetes.

Retinopathy screening in patients with type 1 diabetes diagnosed in young age using a non-mydriatic digital stereoscopic retinal imaging

BACKGROUND

Diabetic retinopathy seriously impairs patients' quality of life, since it represents the first cause of blindness in industrialized countries.

AIM

To estimate prevalence of retinopathy in young Type 1 diabetes patients using a non-mydriatic digital stereoscopic retinal imaging (NMDSRI), and to evaluate the impact of socio-demographic, clinical, and metabolic variables.

SUBJECTS AND METHODS

In 247 young patients glycated hemoglobin (HbA1c), gender, age, pubertal stage, presence of diabetic ketoacidosis (DKA), HLA-DQ heterodimers of susceptibility for Type 1 diabetes, and β-cell autoimmunity at clinical onset were considered. At retinopathy screening, we evaluated age, disease duration, pubertal stage, body mass index (BMI-SDS), insulin requirement, HbA1c levels, other autoimmune diseases, diabetes-related complications, serum concentrations of cholesterol and triglycerides, systolic and diastolic blood pressure.

RESULTS

Retinopathy was found in 26/247 patients: 25 showed background retinopathy, and 1 had a sight-threatening retinopathy. A significant relationship between retinopathy and female gender (p=0.01), duration of disease ≥15 yr (p<0.0001), serum triglycerides levels >65 mg/dl (p=0.012) and mean HbA1c ≥7.5% or >9% (p=0.0014) were found at the multivariate logistic analysis.

CONCLUSIONS

Metabolic control is the most important modifiable factor and promotion of continuous educational process to reach a good metabolic control is a cornerstone to prevent microangiopathic complications. Symptoms appear when the complication is already established; a screening program with an early diagnosis is mandatory to prevent an irreversible damage.

Menopause in women with type 1 diabetes

OBJECTIVE

Our objective was to study age at menopause and the factors associated with it in a large population-based group of Finnish women with childhood-onset type 1 diabetes.

METHODS

We contacted a sample of 978 women with type 1 diabetes and mailed them a questionnaire on their gynecological and reproductive histories, diabetes and its management, other diseases, and lifestyle factors. The questionnaire survey was repeated 3 years later among those 641 who responded in the first round and were eligible to take part. Both cross-sectional and retrospective epidemiological cohort study designs were applied to study factors associated with the occurrence of menopause.

RESULTS

The median age at cessation of menstruation observed in women with type 1 diabetes was 52.5 years, not lower than that of the general Finnish population (median, 51 y). Women with end-stage renal disease (prevalence ratio, 2.22; 95% CI, 1.22-4.02; P = 0.009) or proliferative retinopathy (prevalence ratio, 1.89; 95% CI, 1.11-3.21; P = 0.02) were more likely than others to have entered menopause by the time of the study. Both associations remained statistically significant after age adjustment.

CONCLUSIONS

Age at menopause in women with type 1 diabetes is not lower than that in the general population in Finland. The only statistically significant factors independently associated with earlier menopause in our study were microvascular complications, that is, end-stage renal disease and proliferative retinopathy.

Long-term mortality and retinopathy in type 1 diabetes

The incidence of type 1 diabetes is increasing in Denmark as well as the rest of the world. Due to diabetes-related micro- and macrovascular complications, the morbidity and the mortality is higher among type 1 diabetic patients. The aim of this thesis was to examine a population-based cohort of 727 type 1 diabetic patients from Fyn County, Denmark, with an onset of diabetes before 1 July 1973 in order to: (1) Evaluate the all-cause mortality rates and the influence of sex, duration of diabetes and calendar year of diagnosis in a 33-year follow-up (Paper I). (2) Examine glycaemic regulation, lipids and renal dysfunction as risk factors for all-cause mortality, cardiovascular mortality and IHD (Paper II). (3) Estimate the prevalence of DR as well as the 25-year incidence of PDR and associated risk factors in long-time surviving patients (Paper III). (4) To compare the grading of DR between ETDRS seven standard field 30 degrees stereoscopic colour films and nine field 45 degrees monoscopic digital colour images in long-term surviving patients (Paper IV). In the years 1973-2006 an overall MR of 22.3 per 1000 person-years was found. Furthermore a relative mortality of 3.4 was found as compared to the general population in Denmark. The relative mortality was especially high for patients aged 30-39 (SMR 9.8). There was a tendency towards a better survival for patients diagnosed after 1964. This was especially seen for men. Diabetes was the most common cause of death for those who died in the group. In 1993-1996 blood samples were drawn and glycaemic regulation, lipids and renal markers were subsequently used as predictors of all-cause mortality, cardiovascular mortality and ischaemic heart disease. Glycaemic regulation, dyslipidaemia and creatinine were all significantly associated with all three endpoints. Furthermore, variations in glycaemic control were also identified as a risk factor for overall mortality. Two hundred and one patients were examined for diabetic retinopathy in 1981-1982 and 2007-2008. At follow-up, 97.0% had DR and 42.9% of all patients without PDR at baseline developed this during the follow-up period. Patients who had had a poor glycaemic regulation as well as those who had NPDR at baseline were more likely to develop PDR than the remaining patients. On the other hand, other risk factors such as high blood pressure and proteinuria did not predict PDR. In the comparative study between ETDRS seven standard field 30 degrees stereoscopic colour films and nine field 45 degrees monoscopic digital colour images, 43 eyes of 43 patients were examined in 2008. A poor correlation was found between the two methods: only 29.3% were graded alike. In the remaining, the level of DR was graded higher in the digital photos. Among these, PDR was detected in three eyes using digital photos but remained undetected on all films. This suggests that digital photos with wide fields are the best way to detect DR in long-term type 1 diabetic patients. Overall, it is concluded that mortality is still higher among type 1 diabetic patients. This depends, among other things, on glycaemic regulation, lipid status and, partly, renal dysfunction. Diabetic retinopathy is almost universal in long-term type 1 diabetic patients, and almost half of all patients will develop PDR in 25 years. Nine field digital photos provide the best grading of retinopathy in long-term type 1 diabetic patients.

Prevalence and 25 year incidence of proliferative retinopathy among Danish type 1 diabetic patients

AIMS/HYPOTHESIS

This study aimed to evaluate the prevalence of retinopathy in long-surviving type 1 diabetic patients. It also investigated the 25 year incidence of proliferative retinopathy and associated risk factors in a Danish population-based cohort.

METHODS

A population-based cohort of 727 type 1 diabetic patients from Fyn County, Denmark, was identified in 1973. In 1981-1982, baseline retinopathy was graded and other risk factors were assessed in 573 patients. Twenty-five years later, 308 patients were still alive. Of these, 201 (65.3%) were re-examined at follow-up in 2007-2008.

RESULTS

The median age and duration of diabetes at follow-up were 58.8 and 43 years, respectively. At follow-up, the prevalence of diabetic retinopathy was 97.0%. Non-proliferative retinopathy was found in 45.8%, and 51.2% had proliferative retinopathy. The 25 year incidence of proliferative retinopathy was 42.9% among patients at risk. In a multivariate analysis, baseline HbA(1) (OR 2.14 per 1% increase, 95% CI 1.06-4.31) and non-proliferative retinopathy (OR 4.61, 95% CI 1.94-11.0) were the only risk factors for incident proliferative retinopathy. The long-term incidence of proliferative retinopathy was not associated with baseline duration of diabetes, proteinuria, smoking, body mass index, maculopathy or systolic or diastolic blood pressure.

CONCLUSIONS/INTERPRETATION

Retinopathy among long-surviving type 1 diabetic patients is almost universal. Proliferative retinopathy was found in half of these patients. In addition, the 25 year incidence of proliferative retinopathy was high. Baseline glycaemic regulation and non-proliferative retinopathy were identified as risk factors for incident proliferative retinopathy.

Effect of candesartan on prevention (DIRECT-Prevent 1) and progression (DIRECT-Protect 1) of retinopathy in type 1 diabetes: randomised, placebo-controlled trials

BACKGROUND

Results of previous studies suggest that renin-angiotensin system blockers might reduce the burden of diabetic retinopathy. We therefore designed the DIabetic REtinopathy Candesartan Trials (DIRECT) Programme to assess whether candesartan could reduce the incidence and progression of retinopathy in type 1 diabetes.

METHODS

Two randomised, double-blind, parallel-design, placebo-controlled trials were done in 309 centres worldwide. Participants with normotensive, normoalbuminuric type 1 diabetes without retinopathy were recruited to the DIRECT-Prevent 1 trial and those with existing retinopathy were recruited to DIRECT-Protect 1, and were assigned to candesartan 16 mg once a day or matching placebo. After 1 month, the dose was doubled to 32 mg. Investigators and participants were unaware of the treatment allocation status. The primary endpoints were incidence and progression of retinopathy and were defined as at least a two-step and at least a three-step increase on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, respectively. These trials are registered with ClinicalTrials.gov, numbers NCT00252733 for DIRECT-Prevent 1 and NCT00252720 for DIRECT-Protect 1.

FINDINGS

1421 participants (aged 18-50 years) were randomly assigned to candesartan (n=711) or to placebo (n=710) in DIRECT-Prevent 1, and 1905 (aged 18-55 years) to candesartan (n=951) or to placebo (n=954) in DIRECT-Protect 1. Incidence of retinopathy was seen in 178 (25%) participants in the candesartan group versus 217 (31%) in the placebo group. Progression of retinopathy occurred in 127 (13%) participants in the candesartan group versus 124 (13%) in the placebo group. Hazard ratio (HR for candesartan vs placebo) was 0.82 (95% CI 0.67-1.00, p=0.0508) for incidence of retinopathy and 1.02 (0.80-1.31, p=0.85) for progression of retinopathy. The post-hoc outcome of at least a three-step increase for incidence yielded an HR of 0.65 (0.48-0.87, p=0.0034), which was attenuated but still significant after adjustment for baseline characteristics (0.71, 0.53-0.95, p=0.046). Final ETDRS level was more likely to have improved with candesartan treatment in both DIRECT-Prevent 1 (odds 1.16, 95% CI 1.05-1.30, p=0.0048) and DIRECT-Protect 1 (1.12, 95% CI 1.01-1.25, p=0.0264). Adverse events did not differ between the treatment groups.

INTERPRETATION

Although candesartan reduces the incidence of retinopathy, we did not see a beneficial effect on retinopathy progression.

Role of blood pressure in development of early retinopathy in adolescents with type 1 diabetes: prospective cohort study

OBJECTIVE

To examine the relation between blood pressure and the development of early retinopathy in adolescents with childhood onset type 1 diabetes.

DESIGN

Prospective cohort study.

SETTING

Diabetes Complications Assessment Service at the Children's Hospital at Westmead, Sydney, Australia.

PARTICIPANTS

1869 patients with type 1 diabetes (54% female) screened for retinopathy with baseline median age 13.4 (interquartile range 12.0-15.2) years, duration 4.9 (3.1-7.0) years, and albumin excretion rate of 4.4 (3.1-6.8) microg/min plus a subgroup of 1093 patients retinopathy-free at baseline and followed for a median 4.1 (2.4-6.6) years.

MAIN OUTCOME MEASURES

Early background retinopathy; blood pressure.

RESULTS

Overall, retinopathy developed in 673 (36%) participants at any time point. In the retinopathy-free group, higher systolic blood pressure (odds ratio 1.01, 95% confidence interval 1.003 to 1.02) and diastolic blood pressure (1.01, 1.002 to 1.03) were predictors of retinopathy, after adjustment for albumin excretion rate (1.27, 1.13 to 1.42), haemoglobin A(1c) (1.08, 1.02 to 1.15), duration of diabetes (1.16, 1.13 to 1.19), age (1.13, 1.08 to 1.17), and height (0.98, 0.97 to 0.99). In a subgroup of 1025 patients with albumin excretion rate below 7.5 microg/min, the cumulative risk of retinopathy at 10 years' duration of diabetes was higher for those with systolic blood pressure on or above the 90th centile compared with those below the 90th centile (58% v 35%, P=0.03). The risk was also higher for patients with diastolic blood pressure on or above the 90th centile compared with those below the 90th centile (57% v 35%, P=0.005).

CONCLUSIONS

Both systolic and diastolic blood pressure are predictors of retinopathy and increase the probability of early retinopathy independently of incipient nephropathy in young patients with type 1 diabetes.

Care of vision and ocular health in diabetic members of a national diabetes organization: a cross-sectional study

Background

Regular examination and early treatment of diabetic retinopathy can prevent visual loss. The aim of the study was to describe the care of vision and ocular health in people with diabetes in Norway.

Methods

A cross-sectional questionnaire survey of a random sample (n = 1,887) of the Norwegian Diabetic Associations' (NDA) members was carried out in 2005. Questions were asked about care of vision and ocular health, history of ocular disease and visual symptoms, general medical history and diabetes management. The study was approved by the Regional Committee for Medical Research Ethics.

Results

The response rate was 74%. Forty-four questionnaires with incomplete data regarding gender, age or type of diabetes were excluded, leaving 1352 cases (52% females) for analysis. 451 (33%) had type 1 and 901 (67%) had type 2 diabetes, the mean duration of diabetes was respectively, 22 (sd ± 14) and 10 (sd ± 9) years. In all 1,052 (78%) had their eyes examined according to guidelines and 1,169 (87%) confirmed to have received information about regular eye examinations. One in two recalled to have received such information from their general practitioner. To have received information about the importance of eye examinations (PR 3.1, 95% CI 2.4 to 4.0), and diabetes duration > 10 years (PR 1.2, 95% CI 1.2 to 1.3), were independently associated with reporting regular eye examinations. A history of diabetic retinopathy was reported by 178 (13%) responders, of which 101 (57%) reported a history of laser treatment. Responders who had regular eye examinations reported more frequently a history of diabetic retinopathy (19% vs. 5%, p < 0.001). The frequency of retinopathy was significantly higher in responders with reported HbA1c values above treatment target (23% vs. 13%, p = 0.001). However, in responders who were not regularly examined, there was no difference in reported frequency of retinopathy with regard to HbA1c level.

Conclusion

Eight out of ten diabetic members of the NDA had their eyes examined according to current guidelines and the majority was well informed about the risk of vision loss due to diabetes. The results indicate that the reported history of diabetic retinopathy likely underestimates the prevalence of retinopathy.

Suspected retinopathies in Norwegian optometric practice with emphasis on patients with diabetes: a cross-sectional study

Background

The scope of optometry differs worldwide. In Norway the vast majority of optometrists perform ophthalmoscopy as part of their routine examinations. The aim of this study was to describe the frequency of suspected retinopathies in patients seen for routine optometric examination and to determine how optometrists deal with these patients.

Methods

212 optometrists participated in a questionnaire survey and a practice registration during November 2004 – May 2005. In the practice registration, details for 20 consecutive patient encounters were recorded. Data were analysed by chi-square tests and multiple logistic regression.

Results

All optometrist stated that ocular history taking was an integrated part of their routine examination, while general health and diabetes history were routinely addressed by 59% and 42% of the optometrists, respectively. During the practice registration 4,052 patient encounters were recorded. Ophthalmoscopy was performed in 88% of the patients, of which 2% were dilated fundus examinations. Retinopathy was suspected in 106 patients, of whom 31 did not report a previous history of ocular or systemic disease. Old age (75+), hypertension and diabetes strongly predicted retinopathy with odds ratio (95% CI) of 6.4 (4.2 to 9.9), 3.8 (2.4 to 6.0) and 2.5 (1.4 to 4.7), respectively. Diabetic retinopathy was seen in 10% of diabetic patients and suspected in 0.2% of patients with no established history of diabetes. Retinopathy was not confirmed in 9 out 18 patients with a history of diabetic retinopathy; seven of these had undergone laser treatment. Out of the 106 patients with findings of retinopathy, 28 were referred to an ophthalmologist or a general practitioner (GP), written reports were sent to a GP in 16 cases, ten patients were urged to contact their GP for further follow up, while 52 were considered in need of routine optometric follow up only.

Conclusion

Optometric practice provides a low threshold setting for detecting cases of ocular disease and retinal manifestations of systemic disease in the population. At present diagnosis of retinopathy in Norwegian optometric practice is unreliable. There are potentials for improving the optometrists' routine examination, their patient management patterns and collaboration routines with medical doctors.