Guideline Recommendations on Behavioral and Psychological Symptoms of Dementia: A Systematic Review

OBJECTIVE

To synthesize recommendations on assessing and managing behavioral and psychological symptoms of dementia (BPSDs) in existing clinical practice guidelines on dementia care to learn from and adapt recommendations to a Canadian context and language for describing BPSDs.

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

Moderate to high-quality clinical practice guidelines on dementia care that made 1 or more recommendations on BPSD assessment or management.

METHODS

We searched MEDLINE, Embase, JBI EBM, PsycINFO, AgeLine, and gray literature for clinical practice guidelines on dementia care making recommendations on BPSD, published between January 1, 2011, and October 13, 2022. Two independent reviewers conducted study screening and data abstraction. Four independent reviewers completed quality appraisal using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool; included guidelines had a mean overall AGREE II score ≥4.

RESULTS

Our systematic review identified 23 moderate to high-quality clinical practice guidelines (264 recommendations). The mean overall quality score on the AGREE II tool ranged from 4 to 6.5. Recommendations were clearly presented (mean clarity of presentation score 73.5%), but guideline applicability was not consistently addressed (mean applicability score 39.3%). BPSD was the most prevalent term describing neuropsychiatric symptoms (number of guidelines [n] = 14). People with lived experience contributed to 6 guidelines (26.1%). Ten guidelines (43.5%) described 1 or more health equity considerations. Guidelines made recommendations for assessing and managing agitation (n = 12), aggression (n = 10), psychosis (n = 11), depression (n = 9), anxiety (n = 5), apathy (n = 6), inappropriate sexual behavior (n = 3), nighttime behavior (n = 5), and eating disturbances (n = 3). There was substantial variability in recommendation statements, evidence quality assigned to each statement, and strength of recommendations.

CONCLUSIONS AND IMPLICATIONS

There are several moderate to high-quality clinical practice guidelines making recommendations on BPSD assessment and management, but variability in recommendation statements across guidelines and insufficient consideration of guideline applicability may hamper guideline dissemination and implementation in clinical practice.

Prevalence of Mental Health Disorders Among Individuals Experiencing Homelessness: A Systematic Review and Meta-Analysis

Importance

Several factors may place people with mental health disorders, including substance use disorders, at increased risk of experiencing homelessness and experiencing homelessness may also increase the risk of developing mental health disorders. Meta-analyses examining the prevalence of mental health disorders among people experiencing homelessness globally are lacking.

Objective

To determine the current and lifetime prevalence of mental health disorders among people experiencing homelessness and identify associated factors.

Data Sources

A systematic search of electronic databases (PubMed, MEDLINE, PsycInfo, Embase, Cochrane, CINAHL, and AMED) was conducted from inception to May 1, 2021.

Study Selection

Studies investigating the prevalence of mental health disorders among people experiencing homelessness aged 18 years and older were included.

Data Extraction and Synthesis

Data extraction was completed using standardized forms in Covidence. All extracted data were reviewed for accuracy by consensus between 2 independent reviewers. Random-effects meta-analysis was used to estimate the prevalence (with 95% CIs) of mental health disorders in people experiencing homelessness. Subgroup analyses were performed by sex, study year, age group, region, risk of bias, and measurement method. Meta-regression was conducted to examine the association between mental health disorders and age, risk of bias, and study year.

Main Outcomes and Measures

Current and lifetime prevalence of mental health disorders among people experiencing homelessness.

Results

A total of 7729 citations were retrieved, with 291 undergoing full-text review and 85 included in the final review (N = 48 414 participants, 11 154 [23%] female and 37 260 [77%] male). The current prevalence of mental health disorders among people experiencing homelessness was 67% (95% CI, 55-77), and the lifetime prevalence was 77% (95% CI, 61-88). Male individuals exhibited a significantly higher lifetime prevalence of mental health disorders (86%; 95% CI, 74-92) compared to female individuals (69%; 95% CI, 48-84). The prevalence of several specific disorders were estimated, including any substance use disorder (44%), antisocial personality disorder (26%), major depression (19%), schizophrenia (7%), and bipolar disorder (8%).

Conclusions and Relevance

The findings demonstrate that most people experiencing homelessness have mental health disorders, with higher prevalences than those observed in general community samples. Specific interventions are needed to support the mental health needs of this population, including close coordination of mental health, social, and housing services and policies to support people experiencing homelessness with mental disorders.

Timely Yet Long Overdue: Canadian Standards for Long-Term Care Homes

The impact of the COVID-19 pandemic highlighted systemic problems in Canadian long-term care (LTC). While high mortality rates in LTC received significant attention, the pandemic also took an enormous toll on mental health of LTC residents, where mental health conditions, including cognitive disorders, are already much higher than in other community settings. The pandemic resulted in a renewed interest in improving quality of care in LTC and led to the recent development of several National Standards of Canada. The newly available Standards set ambitious targets, but many of the standards are practical and essential to moving beyond a focus on safety and physical needs in LTC and towards one that supports residents as whole persons. While the standards support good mental health indirectly, there is a need to recognize mental health in these settings as a fundamental human right and essential to quality of life, and for this to be reflected in ongoing and future standards development. Ensuring existing and forthcoming National Standards are meaningfully implemented, in whole or in part, will require extensive efforts at multiple levels. The guidance provided by Canadian Standards will shape this transformative process, necessitating aligned federal and provincial investments and policies, and stakeholder engagement to bring about the envisioned high-quality care.

Association Between Long-Term Care Facility Staffing Levels and Antipsychotic Use in US Long-Term Care Facilities

OBJECTIVES

Inappropriate use of antipsychotics is an indicator of quality of care in long-term care (LTC) facilities. There is evidence to suggest that staffing levels in LTC may be associated with the rates of inappropriate antipsychotic use. This study sought to examine the association between staffing and antipsychotic prescribing in LTC facilities.

DESIGN

Cross-sectional study investigated the association between reported staffing levels and the frequency of inappropriate antipsychotic prescribing at US LTC facilities between 2016 and 2018.

SETTING AND PARTICIPANTS

Data from the Nursing Home Compare and LTCFocus datasets were linked, which contain information from the Minimum Data Set database on facility characteristics and staffing measures from the Payroll-Based Journal system. A final sample set of 10,436 facilities was used.

METHODS

Descriptive statistics were calculated for all variables of interest. An unadjusted linear correlation analysis and linear regression were performed. Potential confounders were investigated by comparison across low-vs high-staffing facilities where adjusted for in regression analyses.

RESULTS

The mean staff level for the facilities was identified as 3.69 (SD = 0.67) staffing hours per patient per day, and the mean antipsychotic use rate across all facilities was 15.24% (SD = 8.62%). There was a 0.75% decrease in inappropriate antipsychotic prescribing per unit increase in overall staff-to-patient ratio. When looking at staffing types, a 3.09% decrease in inappropriate antipsychotic prescribing per unit increase in licensed staff hours. More specifically, we saw a 2.25% decrease per unit increase in RN staffing hours, a 1.83% decrease per unit increase in LPN staffing hours, and nursing aide staffing hours were not associated with antipsychotic use.

CONCLUSIONS AND IMPLICATIONS

These findings provide support for policy-based interventions to decrease antipsychotic use in LTC facilities by improving staffing skill mix and staffing levels. The results may also inform nursing staff education and training on antipsychotic prescribing practices.

Prevalence and factors associated with polypharmacy: a systematic review and Meta-analysis

Introduction

Polypharmacy is commonly associated with adverse health outcomes. There are currently no meta-analyses of the prevalence of polypharmacy or factors associated with polypharmacy. We aimed to estimate the pooled prevalence of polypharmacy and factors associated with polypharmacy in a systematic review and meta-analysis.

Methods

MEDLINE, EMBASE, and Cochrane databases were searched for studies with no restrictions on date. We included observational studies that reported on the prevalence of polypharmacy among individuals over age 19. Two reviewers extracted study characteristics including polypharmacy definitions, study design, setting, geography, and participant demographics. The risk of bias was assessed using the Newcastle-Ottawa Scales. The main outcome was the prevalence of polypharmacy and factors associated with polypharmacy prevalence. The pooled prevalence estimates of polypharmacy with 95% confidence intervals were determined using random effects meta-analysis. Subgroup analyses were undertaken to evaluate factors associated with polypharmacy such as polypharmacy definitions, study setting, study design and geography. Meta-regression was conducted to assess the associations between polypharmacy prevalence and study year.

Results

106 full-text articles were identified. The pooled estimated prevalence of polypharmacy in the 54 studies reporting on polypharmacy in all medication classes was 37% (95% CI: 31-43%). Differences in polypharmacy prevalence were reported for studies using different numerical thresholds, study setting, and publication year. Sex, study geography, study design and geographical location were not associated with differences in polypharmacy prevalence.

Discussion

Our review highlights that polypharmacy is common particularly among older adults and those in inpatient settings. Clinicians should be aware of populations who have an increased likelihood of experiencing polypharmacy and efforts should be made to review the appropriateness of prescribed medications and occurrence of adverse effects potentially associated with polypharmacy.

Conclusions and implications

Clinicians should be aware of the common occurrence of polypharmacy and undertake efforts to minimize inappropriate polypharmacy whenever possible.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03279-x.

Staff perceptions of the consequences of COVID-19 on quality of dementia care for residents in Ontario long-term care homes

OBJECTIVES

The first wave of the COVID-19 pandemic necessitated extensive infection control measures in long-term care (LTC) and had a significant impact on staffing and services. Anecdotal reports indicate that this negatively affected LTC residents' quality of care and wellbeing, but there is scarce evidence on the effects of COVID-19 on quality of dementia care in LTC.

METHODS

From December 2020 to March 2021, we conducted a cross-sectional online survey among staff who worked in LTC homes in Ontario, Canada. Survey questions examined staffs' perceptions of the impact of COVID-19 on dementia quality of care during the initial wave of the COVID-19 pandemic (beginning 1 March 2020).

RESULTS

There were a total of 227 survey respondents; more than half reported both worsened overall quality of care (51.3%) and worsening of a majority of specific quality of care measures (55.5%). Measures of cognitive functioning, mobility and behavioural symptoms were most frequently described as worsened. Medical and allied/support staff had the highest odds of reporting overall worsened quality of care, while specialized behavioural care staff and those with more experience in LTC were less likely to. LTC home factors including rural location and smaller size, staffing challenges, higher number of outbreaks and less COVID-19 preparedness were associated with increased odds of perceived worsening of quality of dementia care outcomes.

CONCLUSIONS

These findings suggest that COVID-19 pandemic restrictions and related effects such as inadequate staffing may have contributed to poor quality of care and outcomes for those with dementia in LTC.

CCCDTD5 recommendations on the deprescribing of cognitive enhancers in dementia

INTRODUCTION

Cognitive enhancers (ie, cholinesterase inhibitors and memantine) can provide symptomatic benefit for some individuals with dementia; however, there are circumstances in which the risks of continuing treatment may potentially outweigh benefits. The decision to deprescribe cognitive enhancers must consider each patient's preferences, treatment indications, current clinical status and symptoms, prognosis, and dementia type.

METHODS

The 5th Canadian Consensus Conference on the Diagnosis and Treatment of Dementia (CCCDTD5) established a subcommittee of experts to review current evidence on the deprescribing of cognitive enhancers. The questions answered by this group included: When should cognitive enhancers be deprescribed in persons with dementia and mild cognitive impairment? How should cognitive enhancers be deprescribed? And, what clinical factors should be considered when deprescribing cognitive enhancers?

RESULTS

Patient and care-partner preferences should be incorporated into all decisions to deprescribe cognitive enhancers. Cognitive enhancers should be discontinued in individuals without ongoing evidence of benefit or when the indication for cognitive enhancer use was inappropriate (eg, mild cognitive impairment). Deprescribing should occur gradually and cognitive enhancers should be reinitiated if patients' cognition or function deteriorates. Cognitive enhancers should be continued in individuals whose neuropsychiatric symptoms improve in response to treatment. Clinicians should not deprescribe cognitive enhancers in individuals with significant neuropsychiatric symptoms until symptoms have stabilized.

CONCLUSION

CCCDTD5 deprescribing recommendations provide evidence-informed recommendations related to cognitive enhancer deprescribing that will facilitate shared decision making among patients, care partners, and clinicians.

Barriers and facilitators to person-centred infection prevention and control: results of a survey about the Dementia Isolation Toolkit

Background

People working in long-term care homes (LTCH) face difficult decisions balancing the risk of infection spread with the hardship imposed on residents by infection control and prevention (ICP) measures. The Dementia Isolation Toolkit (DIT) was developed to address the gap in ethical guidance on how to safely and effectively isolate people living with dementia while supporting their personhood. In this observational study, we report the results of a survey of LTCH staff on barriers and facilitators regarding isolating residents, and the impact of the DIT on staff moral distress.

Methods

We completed an online cross-sectional survey. Participants (n = 207) were staff working on-site in LTCH in Ontario, Canada since March 1, 2020, with direct or indirect experience with the isolation of residents. LTCH staff were recruited through provincial LTCH organizations, social media, and the DIT website. Survey results were summarized, and three groups compared, those: (1) unfamiliar with, (2) familiar with, and (3) users of the DIT.

Results

61% of respondents identified distress of LTCH staff about the harmful effects of isolation on residents as a major barrier to effective isolation. Facilitators for isolation included delivery of 1:1 activity in the resident’s room (81%) and designating essential caregivers to provide support (67%). Almost all respondents (84%) reported an increase in moral distress. DIT users were less likely to report an impact of moral distress on job satisfaction (odds ratio (OR) 0.41, 95% CI 0.19-0.87) with 48% of users reporting the DIT was helpful in reducing their level of moral distress.

Conclusions

Isolation as an ICP measure in LTCH environments creates moral distress among staff which is a barrier to its effectiveness. ICP guidance to LTCH would be strengthened by the inclusion of a dementia-specific ethical framework that addresses how to minimize the harms of isolation on both residents and staff.

Development and dissemination of an ethical guidance and person-centred isolation care planning tool to support the care of people with dementia during the COVID-19 pandemic

Background

Long‐term care (LTC) residents have been disproportionately impacted by the COVID‐19 pandemic, both from the virus itself and the restrictions in effect for infection prevention and control. Many barriers exist in LTC to prevent the effective isolation of suspect or confirmed COVID‐19 cases. Furthermore, these measures have a severe impact on the well‐being of LTC residents. Our aim was to develop a guide for long‐term care to address the ethical challenges associated with isolating dementia patients during the pandemic. The Dementia Isolation Toolkit (DIT) was developed by members of the research team in partnership with LTC stakeholders to address: 1) the practical challenges of isolating or quarantining people with dementia in a compassionate, safe, and effective manner; and 2) the need for ethical guidance to support decision‐making regarding isolation and infection control in LTC, to prevent indecision and moral distress. To develop the DIT the team reviewed and synthesized the literature on pandemic ethics in a plain‐language document, which was then reviewed by our partners and stakeholders. The final ethical guidance tool includes a discussion of the ethics around infection control measures in a pandemic, an ethical decision‐making tool, and a person‐centred isolation care planning tool. The ethical guidance tool has been downloaded more than 6500 times since it was published (bit.ly/dementiatoolkit), and has been disseminated internationally. The worksheets are being used during outbreaks to support care and decision‐making, as well as proactively, to prepare for outbreaks by developing isolation care plans. There is a need for support for ethical decision‐making in the context of a pandemic, particularly in settings such as LTC. Future studies will evaluate the implementation of the tool and its impact in addressing moral distress in health care providers in long‐term care.

Position Statement for Mental Health Care in Long-Term Care During COVID-19

COVID-19 has disproportionately impacted older adults in long-term care (LTC) facilities in Canada. There are opportunities to learn from this crisis and to improve systems of care in order to ensure that older adults in LTC enjoy their right to the highest attainable standard of health. Measures are needed to ensure the mental health of older adults in LTC during COVID-19. The Canadian Academy of Geriatric Psychiatry (CAGP) and Canadian Coalition for Seniors' Mental Health (CCSMH) have developed the following position statements to address the mental health needs of older adults in LTC facilities, their family members, and LTC staff. We outlined eight key considerations related to mental health care in LTC during COVID-19 to optimize the mental health of this vulnerable population during the pandemic.

THU0614-HPR ASSESSING THE EFFECT OF INTERVENTIONS FOR AXIAL SPONDYLOARTHRITIS ACCORDING TO THE ENDORSED ASAS/OMERACT CORE OUTCOME SET: A META-RESEARCH STUDY OF TRIALS INCLUDED IN COCHRANE REVIEWS

Background:

The Assessment of SpondyloArthritis international Society (ASAS) has defined separate core sets for: i) symptom-modifying anti-rheumatic drugs (SM-ARD), ii) clinical record keeping, and iii) disease-controlling anti-rheumatic therapy (DC-ART). These all include the following domains: ‘physical function’, ‘pain’, ‘spinal mobility’, ‘spinal stiffness’ and ‘patient global assessment’ (PGA). The core set for clinical record keeping further includes the domains ‘peripheral joints’ and ‘acute phase reactants’, and the core set for DC-ART further includes the domains ‘fatigue’, ‘spine/hip radiographs’.

Objectives:

To assess the effect of interventions for each of the 9 axSpA core domains.

Methods:

We investigated the efficacy across all interventions included in Cochrane reviews according to the core outcome set for axSpA, as reported in these eligible axSpA trials. We combined data using the standardized mean difference (SMD) to meta-analyze outcomes involving similar constructs. By meta-regression analysis, we examined the effect for each of the nine separate SMD measures on the primary endpoint across all trials.

Results:

Among 85 articles screened, we included 43 trials with 63 randomized comparisons. Mean (SD) number of core outcomes domains measured for SM-ARD trials was 4.2 (1.7). 6 trials assessed all 5 proposed domains. Mean (SD) for number of core outcome domains for DC-ART trials was 5.8 (1.7). Unfortunately, no trials assessed all 9 domains. 8 trials were judged to have high risk of selective outcome reporting. The most responsible core domains for achieving success in meeting the primary objective per trial were pain; OR (95% CI) 5.19 (2.28, 11.77) and PGA; OR (95% CI) 1.87 (1.14, 3.07).

Conclusion:

Overall outcome reporting was good for SM-ARD trials, and poor for DC-ART trials. None of the DC-ART trials assessed all 9 domains. Outcome-reporting bias and ‘missing data’ should be reduced by implementing the endorsed ASAS/OMERACT outcome domains in all clinical trials. Our findings suggest that PGA and pain likely provide a holistic assessment of disease beyond “objective measures” of spinal inflammation.

Disclosure of Interests:

Rikke Asmussen Andreasen: None declared, Lars Erik Kristensen Consultant of: UCB Pharma (Advisory Board), Sannofi (Advisory Board), Abbvie (Advisory Board), Biogen (Advisory Board), Speakers bureau: AbbVie, Amgen, Biogen, Bristol-Myers Squibb,Celgene, Eli Lilly, Gilead, Forward Pharma, Janssen Pharmaceuticals, MSD, Novartis, Pfizer, and UCB Pharma, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Vibeke Strand Consultant of: AbbVie, Amgen, Biogen, Celltrion, Consortium of Rheumatology Researchers of North America, Crescendo Bioscience, Eli Lilly, Genentech/Roche, GlaxoSmithKline, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Sanofi, UCB, Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Maarten de Wit Grant/research support from: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Consultant of: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Speakers bureau: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Torkell Ellingsen: None declared, Inger Marie Jensen Hansen: None declared, Jamie Kirkham: None declared, George Wells: None declared, Peter Tugwell: None declared, Lara Maxwell: None declared, Maarten Boers: None declared, Kenneth Egstrup: None declared, Robin Christensen Grant/research support from: Dr. Christensen reports non-financial support from Board membership, grants from Consultancy (AbbVie, Amgen, Axellus A/S, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Eli Lilly, Hospira, MSD, Norpharma, Novartis, Orkla Health, Pfizer, Roche, Sobi, Takeda), personal fees from Employment (Research Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark), non-financial support from Expert testimony, grants from Grants/grants pending (Axellus A/S, AbbVie, Cambridge Weight Plan, Janssen, MSD, Mundipharma, Novartis, and Roche), grants from Payment for lectures including service on speakers bureaus (Abbott, Amgen, Axellus, Bayer HealthCare Pharmaceuticals, Biogen Idec, Bristol-Myers Squibb, Cambridge Weight Plan, Ipsen, Janssen, Laboratoires Expanscience, MSD, Mundipharma, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, Sobi, and Wyeth), grants from Payment for manuscript preparation (Axellus, Bristol-Myers Squibb, and Cambridge Weight Plan, Aleris-Hamlet (via Norpharma)), non-financial support from Patents (planned, pending or issued), non-financial support from Royalties, grants from Payment for development of educational presentations (Bristol-Myers Squibb, MSD, Pfizer), non-financial support from Stock/stock options, grants from Travel/accommodations/meeting expenses unrelated to activities listed (Abbott, AbbVie, Axellus, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Laboratoires Expanscience, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, and Wyeth), non-financial support from Other (err on the side of full disclosure), outside the submitted work; and I am involved in many health-care initiatives and research that could benefit from wide uptake of this publication (including Cochrane, OMERACT, IDEOM, RADS, and the GRADE Working Group).

Musculoskeletal Statistics Unit, The Parker Institute is grateful for the financial support received from public and private foundations, companies and private individuals over the years. The Parker Institute is supported by a core grant from the Oak Foundation; The Oak Foundation is a group of philanthropic organizations that, since its establishment in 1983, has given grants to not-for-profit organizations around the world.., Consultant of: Dr. Christensen reports non-financial support from Board membership, grants from Consultancy (AbbVie, Amgen, Axellus A/S, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Eli Lilly, Hospira, MSD, Norpharma, Novartis, Orkla Health, Pfizer, Roche, Sobi, Takeda), personal fees from Employment (Research Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark), non-financial support from Expert testimony, grants from Grants/grants pending (Axellus A/S, AbbVie, Cambridge Weight Plan, Janssen, MSD, Mundipharma, Novartis, and Roche), grants from Payment for lectures including service on speakers bureaus (Abbott, Amgen, Axellus, Bayer HealthCare Pharmaceuticals, Biogen Idec, Bristol-Myers Squibb, Cambridge Weight Plan, Ipsen, Janssen, Laboratoires Expanscience, MSD, Mundipharma, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, Sobi, and Wyeth), grants from Payment for manuscript preparation (Axellus, Bristol-Myers Squibb, and Cambridge Weight Plan, Aleris-Hamlet (via Norpharma)), non-financial support from Patents (planned, pending or issued), non-financial support from Royalties, grants from Payment for development of educational presentations (Bristol-Myers Squibb, MSD, Pfizer), non-financial support from Stock/stock options, grants from Travel/accommodations/meeting expenses unrelated to activities listed (Abbott, AbbVie, Axellus, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Laboratoires Expanscience, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, and Wyeth), non-financial support from Other (err on the side of full disclosure), outside the submitted work; and I am involved in many health-care initiatives and research that could benefit from wide uptake of this publication (including Cochrane, OMERACT, IDEOM, RADS, and the GRADE Working Group).

Musculoskeletal Statistics Unit, The Parker Institute is grateful for the financial support received from public and private foundations, companies and private individuals over the years. The Parker Institute is supported by a core grant from the Oak Foundation; The Oak Foundation is a group of philanthropic organizations that, since its establishment in 1983, has given grants to not-for-profit organizations around the world.., Speakers bureau: Dr. Christensen reports non-financial support from Board membership, grants from Consultancy (AbbVie, Amgen, Axellus A/S, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Eli Lilly, Hospira, MSD, Norpharma, Novartis, Orkla Health, Pfizer, Roche, Sobi, Takeda), personal fees from Employment (Research Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark), non-financial support from Expert testimony, grants from Grants/grants pending (Axellus A/S, AbbVie, Cambridge Weight Plan, Janssen, MSD, Mundipharma, Novartis, and Roche), grants from Payment for lectures including service on speakers bureaus (Abbott, Amgen, Axellus, Bayer HealthCare Pharmaceuticals, Biogen Idec, Bristol-Myers Squibb, Cambridge Weight Plan, Ipsen, Janssen, Laboratoires Expanscience, MSD, Mundipharma, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, Sobi, and Wyeth), grants from Payment for manuscript preparation (Axellus, Bristol-Myers Squibb, and Cambridge Weight Plan, Aleris-Hamlet (via Norpharma)), non-financial support from Patents (planned, pending or issued), non-financial support from Royalties, grants from Payment for development of educational presentations (Bristol-Myers Squibb, MSD, Pfizer), non-financial support from Stock/stock options, grants from Travel/accommodations/meeting expenses unrelated to activities listed (Abbott, AbbVie, Axellus, Biogen, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Laboratoires Expanscience, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, and Wyeth), non-financial support from Other (err on the side of full disclosure), outside the submitted work; and I am involved in many health-care initiatives and research that could benefit from wide uptake of this publication (including Cochrane, OMERACT, IDEOM, RADS, and the GRADE Working Group).

Musculoskeletal Statistics Unit, The Parker Institute is grateful for the financial support received from public and private foundations, companies and private individuals over the years. The Parker Institute is supported by a core grant from the Oak Foundation; The Oak Foundation is a group of philanthropic organizations that, since its establishment in 1983, has given grants to not-for-profit organizations around the world.

Pulmonary mucormycosis with extensive bronchial necrosis and bronchomediastinal fistula: A case report and review

Mucormycosis is a life-threatening infection caused by fungi in the Mucorales species. It most often affects immunocompromised hosts, including diabetics patients. It can affect a variety of organ systems with pulmonary manifestations being the second most common. In severe cases, significant bronchial necrosis and angioinvasion can be seen. Due to its rarity, such extensive cases are not often reported in literature. We present a case of a 32-year-old man who presented with severe bronchial necrosis, including bronchomediastinal fistula, due to Rhizopus. Despite prompt treatment, he developed massive hemoptysis from invasion of the pulmonary vasculature and died. We also provide a brief review of mucormycosis.

NAT2 variants and toxicity related to anti-tuberculosis agents: a systematic review and meta-analysis

BACKGROUND:

Tuberculosis (TB) patients receiving anti-tuberculosis treatment may experience serious adverse drug reactions (ADRs) such as hepatotoxicity. Variants of the N-acetyltransferase 2 (NAT2) gene may increase the risk of experiencing such toxicity events.

OBJECTIVE:

To provide a comprehensive evaluation of the evidence base for associations between NAT2 variants and anti-tuberculosis drug-related toxicity.

METHOD:

This was a systematic review and meta-analysis. We searched for studies in Medline, PubMed, EMBASE, BIOSIS and Web of Science. We included data from 41 articles (39 distinct cohorts of patients). We pooled effect estimates for each genotype on each outcome using meta-analyses stratified by country.

RESULTS:

We assessed the quality of the included studies, which was variable, with many areas of concern. Slow/intermediate NAT2 acetylators were statistically significantly more likely to experience hepatotoxicity than rapid acetylators (OR 1.59, 95%CI 1.26–2.01). Heterogeneity was not detected in the overall pooled analysis (I² = 0%). NAT2 acetylator status was significantly associated with the likelihood of experiencing anti-tuberculosis drug-related hepatotoxicity.

CONCLUSION:

We encountered several challenges in performing robust syntheses of data from pharmacogenetic studies, and we outline recommendations for the future reporting of pharmacogenetic studies to enable high-quality systematic reviews and meta-analyses to be performed.

Optimizing Prescribing of Antipsychotics in Long-Term Care (OPAL): A Stepped-Wedge Trial

BACKGROUND

Inappropriate antipsychotic prescribing is a key quality indicator by which clinical outcomes might be monitored and improved in long-term care (LTC), but limited evidence exists on the most effective strategies for reducing inappropriate antipsychotic use.

OBJECTIVES

The objective of the study was to evaluate a multicomponent approach to reduce inappropriate prescribing of antipsychotics in LTC.

DESIGN

A prospective, stepped-wedge study design was used to evaluate the effect of the intervention.

SETTINGS AND PARTICIPANTS

Interdisciplinary staff at 10 Canadian LTC facilities.

METHODS

The intervention consisted of an educational in-service, provision of evidence-based tools to assess and monitor neuropsychiatric symptoms (NPS) in dementia, and monthly interprofessional team meetings. The primary outcome was the proportion of residents receiving an antipsychotic without a diagnosis of psychosis using a standardized antipsychotic quality indicator.

RESULTS

The weighted mean change in inappropriate antipsychotic prescribing rate from baseline to 12-month follow-up was -4.6% [standard deviation (SD) = 2.8%, P < .0001], representing a 16.1% (SD = 17.0) relative reduction. After adjusting for site, the odds ratio for the inappropriate antipsychotic prescribing quality indicator at 12 months compared to baseline was 0.73 (95% confidence interval = 0.48-0.94; chi-square = 6.59; P = .01). There were no significant changes in related quality indicators, including falls, restraint use, or behavioral symptoms.

CONCLUSIONS AND IMPLICATIONS

This multicomponent intervention was effective in reducing inappropriate antipsychotic prescribing in LTC without adversely affecting other domains related to quality of care, and offers a practical means by which to improve the care of older adults with dementia in LTC.

Phenotype and Variant Spectrum in the LAMB3 Form of Amelogenesis Imperfecta

Amelogenesis imperfecta (AI) is a heterogeneous group of inherited disorders characterized by abnormal formation of dental enamel, either in isolation or as part of a syndrome. Heterozygous variants in laminin subunit beta 3 ( LAMB3) cause AI with dominant inheritance in the absence of other cosegregating clinical features. In contrast, biallelic loss-of-function variants in LAMB3 cause recessive junctional epidermolysis bullosa, characterized by life-threatening skin fragility. We identified 2 families segregating autosomal dominant AI with variable degrees of a distinctive hypoplastic phenotype due to pathogenic variants in LAMB3. Whole exome sequencing revealed a nonsense variant (c.3340G>T, p.E1114*) within the final exon in family 1, while Sanger sequencing in family 2 revealed a variant (c.3383-1G>A) in the canonical splice acceptor site of the final exon. Analysis of cDNA from family 2 revealed retention of the final intron leading to a premature termination codon. Two unerupted third molar teeth from individual IV:5 in family 2 were subject to computerized tomography and scanning electron microscopy. LAMB3 molar teeth have a multitude of cusps versus matched controls. LAMB3 enamel was well mineralized but pitted. The architecture of the initially secreted enamel was abnormal, with cervical enamel appearing much less severely affected than coronal enamel. This study further defines the variations in phenotype-genotype correlation for AI due to variants in LAMB3, underlines the clustering of nonsense and frameshift variants causing AI in the absence of junctional epidermolysis bullosa, and highlights the shared AI phenotype arising from variants in genes coding for hemidesmosome proteins.

Meta-Analysis of the Prevalence of Major Depressive Disorder Among Older Adults With Dementia

OBJECTIVE

Little is known about the overall prevalence of major depressive disorder (MDD) in persons with dementia (ie, "depression in dementia": DpD). The aim of this systematic review and meta-analysis was to determine the prevalence and factors associated with DpD among older adults (age range 58.7-87.8 years). The protocol was registered in the PROSPERO registry (2015:CRD42015020681).

DATA SOURCES

We searched the following electronic databases: MEDLINE (1946-February 2017), Embase (1980-2017 week 5), and PsycINFO (1967-February 2017) using medical subject headings and free-text search terms for studies in the English language.

STUDY SELECTION

We screened 9,421 studies, and 55 met the inclusion criteria (ie, used validated criteria for both MDD and dementia).

DATA EXTRACTION

Two independent reviewers extracted data from included studies. Meta-analysis was used to determine the pooled estimates and 95% confidence intervals for the prevalence of DpD. Prevalence across dementia subtypes, study setting, diagnostic criteria, and dementia severity was compared in subgroup analyses.

RESULTS

The prevalence of MDD in all-cause dementia was 15.9% (95% CI, 12.6%-20.1%). The prevalence of MDD was higher among individuals with vascular dementia (24.7%) compared to Alzheimer's disease (14.8%). Studies using the provisional diagnostic criteria for DpD reported a higher prevalence (35.6%) compared to studies using either the DSM-III-R (13.2%) or DSM-IV (17.3%) criteria.

CONCLUSIONS

Depression is common among individuals with dementia, and the type of dementia and diagnostic criteria affect prevalence estimates of DpD. Further studies are required to understand factors that lead to the development of DpD and strategies to prevent and treat DpD.

Antipsychotic Use in Dementia

Antipsychotics are necessary for many older adults to treat major mental illnesses or reduce distressing psychiatric symptoms. Current controversy exists over the role of antipsychotics in the management of neuropsychiatric symptoms (NPS) in persons with dementia. Although some NPS may be appropriately and safely treated with antipsychotics, a fine balance must be achieved between the benefits of these medications, which are often modest, and adverse events, which may have significant consequences. Approximately one-third of all persons with dementia are currently prescribed antipsychotic medications, and there is significant variation in the use of antipsychotics across care settings and providers. Reducing the inappropriate or unnecessary use of antipsychotics among persons with dementia has been the focus of increasing attention owing to better awareness of the potential problems associated with these medications. Several approaches can be used to curb the use of antipsychotics among persons with dementia, including policy or regulatory changes, public reporting, and educational outreach. Recently, there has been encouraging evidence of a downward trend in the use of antipsychotics in many long-term care settings, although prescribing rates are still higher than what is likely optimal. Although reducing the inappropriate use of antipsychotics is a complex task, psychiatrists can play an important role via the provision of clinical care and research evidence, contributing to improved care of persons with dementia in Canada and elsewhere.

Who gains clinical benefit from using insulin pump therapy? A qualitative study of the perceptions and views of health professionals involved in the Relative Effectiveness of Pumps over MDI and Structured Education (REPOSE) trial

AIMS

To explore health professionals' views about insulin pump therapy [continuous subcutaneous insulin infusion (CSII)] and the types of individuals they thought would gain greatest clinical benefit from using this treatment.

METHODS

In-depth interviews with staff (n = 18) who delivered the Relative Effectiveness of Pumps Over MDI and Structured Education (REPOSE) trial. Data were analysed thematically.

RESULTS

Staff perceived insulin pumps as offering a better self-management tool to some individuals due to the drip feed of insulin, the ability to alter basal rates and other advanced features. However, staff also noted that, because of the diversity of features on offer, CSII is a more technically complex therapy to execute than multiple daily injections. For this reason, staff described how, alongside clinical criteria, they had tended to select individuals for CSII in routine clinical practice based on their perceptions about whether they possessed the personal and psychological attributes needed to make optimal use of pump technology. Staff also described how their assumptions about personal and psychological suitability had been challenged by working on the REPOSE trial and observing individuals make effective use of CSII who they would not have recommended for this type of therapy in routine clinical practice.

CONCLUSIONS

Our findings add to those studies that highlight the difficulties of using patient characteristics and variables to predict clinical success using CSII. To promote equitable access to CSII, attitudinal barriers and prejudicial assumptions amongst staff about who is able to make effective use of CSII may need to be addressed.

Treatment of early caries lesions using biomimetic self-assembling peptides--a clinical safety trial

OBJECTIVE

We previously reported that a rationally designed biomimetic self-assembling peptide, P₁₁-4, nucleated hydroxyapatite de novo and was apparently capable of in situ enamel regeneration following infiltration into caries-like lesions. Our present aim was to determine the safety and potential clinical efficacy of a single application of P₁₁-4 on early enamel lesions.

MATERIALS AND METHODS

Fifteen healthy adults with Class V 'white spot' lesions received a single application of P₁₁-4. Adverse events and lesion appearances were recorded over 180 days.

RESULTS

Patients treated with P₁₁-4 experienced a total of 11 adverse events during the study, of which two were possibly related to the protocol. Efficacy evaluation suggested that treatment with P₁₁-4 significantly decreased lesion size (p = 0.02) after 30 days and shifted the apparent progression of the lesions from 'arrested/progressing' to 'remineralising' (p <0.001). A highly significant improvement in the global impression of change was recorded at day 30 compared with baseline (p <0.001).

CONCLUSIONS

The results suggest that treatment of early caries lesions with P₁₁-4 is safe, and that a single application is associated with significant enamel regeneration, presumably by promoting mineral deposition within the subsurface tissue.

Non-destructive monitoring of viability in an ex vivo organ culture model of osteochondral tissue

Organ culture is an increasingly important tool in research, with advantages over monolayer cell culture due to the inherent natural environment of tissues. Successful organ cultures must retain cell viability. The aim of this study was to produce viable and non-viable osteochondral organ cultures, to assess the accumulation of soluble markers in the conditioned medium for predicting tissue viability. Porcine femoral osteochondral plugs were cultured for 20 days, with the addition of Triton X-100 on day 6 (to induce necrosis), camptothecin (to induce apoptosis) or no toxic additives. Tissue viability was assessed by the tissue destructive XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide tetrazolium salt) assay method and LIVE/DEAD® staining of the cartilage at days 0, 6 and 20. Tissue structure was assessed by histological evaluation using haematoxylin & eosin and safranin O. Conditioned medium was assessed every 3-4 days for glucose depletion, and levels of lactate dehydrogenase (LDH), alkaline phosphatase (AP), glycosaminoglycans (GAGs), and matrix metalloproteinase (MMP)-2 and MMP-9. Necrotic cultures immediately showed a reduction in glucose consumption, and an immediate increase in LDH, GAG, MMP-2 and MMP-9 levels. Apoptotic cultures showed a delayed reduction in glucose consumption and delayed increase in LDH, a small rise in MMP-2 and MMP-9, but no significant effect on GAGs released into the conditioned medium. The data showed that tissue viability could be monitored by assessing the conditioned medium for the aforementioned markers, negating the need for tissue destructive assays. Physiologically relevant whole- or part-joint organ culture models, necessary for research and pre-clinical assessment of therapies, could be monitored this way, reducing the need to sacrifice tissues to determine viability, and hence reducing the sample numbers necessary.

Perceptions and experiences of using automated bolus advisors amongst people with type 1 diabetes: a longitudinal qualitative investigation

AIMS

We explored people's reasons for, and experiences of, using bolus advisors to determine insulin doses; and, their likes/dislikes of this technology.

SUBJECTS AND METHODS

42 people with type 1 diabetes who had received instruction in use of bolus advisors during a structured education course were interviewed post-course and 6 months later. Data were analysed thematically.

RESULTS

Participants who considered themselves to have poor mathematical skills highlighted a gratitude for, and heavy reliance on, advisors. Others liked and chose to use advisors because they saved time and effort calculating doses and/or had a data storage facility. Follow-up interviews highlighted that, by virtue of no longer calculating their doses, participants could become deskilled and increasingly dependent on advisors. Some forgot what their mealtime ratios were; others reported a misperception that, because they were pre-programmed during courses, these parameters never needed changing. Use of data storage facilities could hinder effective review of blood glucose data and some participants reported an adverse impact on glycaemic control.

DISCUSSION

While participants liked and perceived benefits to using advisors, there may be unintended consequences to giving people access to this technology. To promote effective use, on-going input and education from trained health professionals may be necessary.

Exploring perceived barriers, drivers, impacts and the need for evaluation of public involvement in health and social care research: a modified Delphi study

OBJECTIVE

To explore areas of consensus and conflict in relation to perceived public involvement (PI) barriers and drivers, perceived impacts of PI and ways of evaluating PI approaches in health and social care research.

BACKGROUND

Internationally and within the UK the recognition of potential benefits of PI in health and social care research is gathering momentum and PI is increasingly identified by organisations as a prerequisite for funding. However, there is relatively little examination of the impacts of PI and how those impacts might be measured.

DESIGN

Mixed method, three-phase, modified Delphi technique, conducted as part of a larger MRC multiphase project.

SAMPLE

Clinical and non-clinical academics, members of the public, research managers, commissioners and funders.

FINDINGS

This study found high levels of consensus about the most important barriers and drivers to PI. There was acknowledgement that tokenism was common in relation to PI; and strong support for the view that demonstrating the impacts and value of PI was made more difficult by tokenistic practice. PI was seen as having intrinsic value; nonetheless, there was clear support for the importance of evaluating its impact. Research team cohesion and appropriate resources were considered essential to effective PI implementation. Panellists agreed that PI can be challenging, but can be facilitated by clear guidance, together with models of good practice and measurable standards.

CONCLUSIONS

This study is the first to present empirical evidence of the opinions voiced by key stakeholders on areas of consensus and conflict in relation to perceived PI barriers and drivers, perceived impacts of PI and the need to evaluate PI. As such it further contributes to debate around best practice in PI, the potential for tokenism and how best to evaluate the impacts of PI. These findings have been used in the development of the Public Involvement Impact Assessment Framework (PiiAF), an online resource which offers guidance to researchers and members of the public involved in the PI process.

Exploring areas of consensus and conflict around values underpinning public involvement in health and social care research: a modified Delphi study

OBJECTIVE

There is growing interest in the potential benefits of public involvement (PI) in health and social care research. However, there has been little examination of values underpinning PI or how these values might differ for different groups with an interest in PI in the research process. We aimed to explore areas of consensus and conflict around normative, substantive and process-related values underpinning PI.

DESIGN

Mixed method, three-phase, modified Delphi study, conducted as part of a larger multiphase project.

SETTING

The UK health and social care research community.

PARTICIPANTS

Stakeholders in PI in research, defined as: clinical and non-clinical academics, members of the public, research managers, commissioners and funders; identified via research networks, online searches and a literature review.

RESULTS

We identified high levels of consensus for many normative, substantive and process-related issues. However, there were also areas of conflict in relation to issues of bias and representativeness, and around whether the purpose of PI in health and social care research is to bring about service change or generate new knowledge. There were large differences by group in the percentages endorsing the ethical justification for PI and the argument that PI equalises power imbalances. With regard to practical implementation of PI, research support infrastructures were reported as lacking. Participants reported shortcomings in the uptake and practice of PI. Embedding PI practice and evaluation in research study designs was seen as fundamental to strengthening the evidence base.

CONCLUSIONS

Our findings highlight the extent to which PI is already embedded in research. However, they also highlight a need for 'best practice' standards to assist research teams to understand, implement and evaluate PI. These findings have been used in developing a Public Involvement Impact Assessment Framework (PiiAF), which offers guidance to researchers and members of the public involved in the PI process.

Ag-doped 45S5 Bioglass®-based bone scaffolds by molten salt ion exchange: processing and characterisation

There is increasing interest in developing scaffolds with therapeutic and antibacterial potential for bone tissue engineering. Silver is a proven antibacterial agent which bacteria such as MRSA have little or no defense against. Using an ion exchange method, silver ions have been introduced into 45S5 Bioglass(®) based scaffolds that were fabricated using the foam replication technique. This technique allows the introduction of Ag(+) ions onto the surface of the scaffold without compromising the scaffold bioactivity and other physical properties such as porosity. Controlling the amount of Ag(+) ions introduced onto the surface of the scaffold was achieved by tailoring the ion exchange parameters to fabricate samples with repeatable and predictable Ag(+) ion release behavior. In vitro studies in simulated body fluid were carried out to ensure that the scaffolds maintained their bioactivity after the introduction of Ag(+) ions. It was also shown that the addition of low concentrations (2000:1 w/w) of silver ions supported the attachment and viability of human periodontal ligament stromal cells on the 3D scaffolds. This work has thus confirmed ion exchange as an effective technique to introduce Ag(+) ions into 45S5 Bioglass(®) scaffolds without compromising the basic properties of 45S5 Bioglass(®) which are required for applications in bone tissue engineering.

High resolution imaging of actin filaments in living cells under physilogically relevant conditions using apertureless near-field microscopy

Living cells were used to demonstrate the potential biological applications of the apertureless SNOM when operating under fluid. An oral epithelial squamous cell carcinoma cell line (H357) was imaged under physiological-like conditions using apertureless SNOM following staining with FITC-Phalloidin which preferentially stains intracellular actin filaments of the cytoskeleton. Compared with simultaneously obtained AFM topographic image, the apertureless SNOM data provides greater detail on these cellular structures and the spatial resolution of the apertureless SNOM fluorescence image appears to be about 100 nm.

Changes in the structure and density of oral plaque biofilms with increasing plaque age

In common with many biofilms in nature, oral plaque has been shown to have a heterogeneous structure as shown by confocal microscopy. In the present study we have used confocal laser scanning microscopy (CLSM) to determine changes in the structure of plaque biofilms with increasing plaque age. Natural human plaque biofilms were formed using the Leeds in situ device. Plaque biofilms were allowed to form for periods of 2 days, 1 week, 2 weeks and 4 weeks before removal of the devices and immediate imaging using the CLSM. Confocal imaging showed that the biofilms retained their heterogeneous appearance at each of the time points studied but appeared to have a tendency to become somewhat more dense with increasing time. Image analysis demonstrated that the percentage of biomass within each biofilm increased over time, particularly between 2 days and 1 week, and with increasing depth into the biofilms. In addition, using the CLSM we were able to demonstrate changes in the bacterial flora of the biofilms with time, with many more filamentous forms being present at the 2- and 4-week time points.

Deferasirox for the treatment of iron overload associated with regular blood transfusions (transfusional haemosiderosis) in patients suffering with chronic anaemia: a systematic review and economic evaluation

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of deferasirox for the treatment of iron overload associated with regular blood transfusions in patients with chronic anaemia such as beta-thalassaemia major (beta-TM) and sickle cell disease (SCD).

DATA SOURCES

Electronic databases were searched up to March 2007.

REVIEW METHODS

Methods followed accepted procedures for conducting and reporting systematic reviews and economic evaluations.

RESULTS

A total of 14 randomised controlled trials (RCTs) involving a study population of 1480 (ranging from 13 to 586) met the inclusion criteria. There was a high degree of heterogeneity between trials in terms of trial design and outcome reporting. As such it was only possible to meta-analyse serum ferritin data from six trials making comparisons between deferiprone and DFO and combination therapy and DFO. Only one of the results was statistically significant, favouring combination therapy over DFO alone for serum ferritin at 12 months. How this translates into iron loading in organs such as the heart is unclear, nor was it possible to determine the long-term benefits of chelation therapy. Eight full economic evaluations (one full paper; seven abstracts) were included in the review. The results were generally consistent and appear to demonstrate the cost-effectiveness of deferasirox compared with DFO for the treatment of iron overload in a number of different patient populations and study locations. However, a number of assumptions and, in the case of the long-term studies, extrapolation from short-term RCT data were required, which render the results highly speculative at best. Because of the paucity of long-term data we developed a simple, short-term (1 year) model to assess the costs and benefits of deferasirox, deferiprone and DFO in patients with beta-TM and SCD from an NHS perspective. A number of assumptions were required to generate results and, as such, they should be interpreted as indicative rather than factual. Our model suggests that deferasirox may be a cost-effective strategy compared with DFO, at a cost per quality-adjusted life-year (QALY) below 30,000 pounds per year, for patients with beta-TM and SCD. However, this is highly dependent upon the age of the patient and the use and benefits of balloon infusers to administer DFO. Deferasirox compared with deferiprone is likely to be cost-effective only for young children. Furthermore, if deferiprone is proven to offer the same health benefits as deferasirox, the latter will not be cost-effective for any patient compared with deferiprone.

CONCLUSIONS

In the short term there is little clinical difference between any of the three chelators in terms of removing iron from the blood and liver. Deferasirox may be cost-effective compared with DFO in patients with beta-TM and SCD, but it is unlikely to be cost-effective compared with deferiprone. Elucidating the long-term benefits of chelation therapy, including issues of adverse events and adherence, should be the primary focus for future research. Future work should aim for consistency and transparency in reporting study design and results to aid decision-making when making comparisons across trials.

Self-assembling peptide scaffolds promote enamel remineralization

Rationally designed beta-sheet-forming peptides that spontaneously form three-dimensional fibrillar scaffolds in response to specific environmental triggers may potentially be used in skeletal tissue engineering, including the treatment/prevention of dental caries, via bioactive surface groups. We hypothesized that infiltration of caries lesions with monomeric low-viscosity peptide solutions would be followed by in situ polymerization triggered by conditions of pH and ionic strength, providing a biomimetic scaffold capable of hydroxyapatite nucleation, promoting repair. Our aim was to determine the effect of an anionic peptide applied to caries-like lesions in human dental enamel under simulated intra-oral conditions of pH cycling. Peptide treatment significantly increased net mineral gain by the lesions, due to both increased remineralization and inhibition of demineralization over a five-day period. The assembled peptide was also capable of inducing hydroxyapatite nucleation de novo. The results suggest that self-assembling peptides may be useful in the modulation of mineral behavior during in situ dental tissue engineering.

Penetration of fluoride into natural plaque biofilms

Caries occurs at inaccessible stagnation sites where plaque removal is difficult. Here, the penetration through plaque of protective components, such as fluoride, is likely to be crucial in caries inhibition. We hypothesized that topically applied fluoride would readily penetrate such plaque deposits. In this study, plaque biofilms generated in vivo on natural enamel surfaces were exposed to NaF (1000 ppm F-) for 30 or 120 sec (equivalent to toothbrushing) or for 30 min. Biofilms were then sectioned throughout their depth, and the fluoride content of each section was determined with the use of a fluoride electrode. Exposure to NaF for 30 or 120 sec increased plaque fluoride concentrations near the saliva interface, while concentrations near the enamel surface remained low. Fluoride penetration increased with duration of NaF exposure. Removal of exogenous fluoride resulted in fluoride loss and redistribution. Penetration of fluoride into plaque biofilms during brief topical exposure is restricted, which may limit anti-caries efficacy.

Surface chemistry of enamel apatite during maturation in relation to pH: implications for protein removal and crystal growth

Apatite crystal growth rate and morphology in mineralized tissues are considered to be controlled by surface interaction with extracellular matrix proteins. During enamel maturation where protein is finally removed from crystal surfaces to permit massive crystal growth, pH oscillates between approximately 5.8 and approximately 7.2. With this in mind, a study of enamel apatite surface chemistry in terms of local environmental pH was undertaken. Using atomic force microscopy adhesion force measurements were made between hydroxylated or carboxylated cantilever tips and maturation stage crystals between pH 2 and 10. Adhesion force increased from pH 10 to a maximum at pH 6.6 presumably due to increased hydrogen bonding due to replacement of surface cations (Na, Ca, Mg) with protons and/or protonation of phosphate per se. Below pH 6.6 adhesion force decreased and became very variable indicating that the surface had become unstable probably due to removal of fully protonated phosphate from the surface by adherence to the cantilever tip. Frictional force measurements also revealed 2-3, approximately 30 nm diameter high friction domains in bands across the crystal long axis. Their location mirrored the binding pattern of similarly sized amelogenin aggregates seen in vitro. The data suggests that specific protein binding sites may exist on crystal surfaces and may be released at lower pH by protonation which would lower cationic charge on both crystal surface and ionic charge on the protein. Instability of the crystal surface could also play a role.

The effect of fluoride on the developing tooth

This review aims to outline the effects of fluoride on the biological processes involved in the formation of tooth tissues, particularly dental enamel. Attention has been focused on mechanisms which, if compromised, could give rise to dental fluorosis. The literature is extensive and often confusing but a much clearer picture is emerging based on recent more detailed knowledge of odontogenesis. Opacity, characteristic of fluorotic enamel, results from incomplete apatite crystal growth. How this occurs is suggested by other changes brought about by fluoride. Matrix proteins, associated with the mineral phase, normally degraded and removed to permit final crystal growth, are to some extent retained in fluorotic tissue. Fluoride and magnesium concentrations increase while carbonate is reduced. Crystal surface morphology at the nano-scale is altered and functional ameloblast morphology at the maturation stage also changes. Fluoride incorporation into enamel apatite produces more stable crystals. Local supersaturation levels with regard to the fluoridated mineral will also be elevated facilitating crystal growth. Such changes in crystal chemistry and morphology, involving stronger ionic and hydrogen bonds, also lead to greater binding of modulating matrix proteins and proteolytic enzymes. This results in reduced degradation and enhanced retention of protein components in mature tissue. This is most likely responsible for porous fluorotic tissue, since matrix protein removal is necessary for unimpaired crystal growth. To resolve the outstanding problems of the role of cell changes and the precise reasons for protein retention more detailed studies will be required of alterations to cell function, effect on specific protein species and the nano-chemistry of the apatite crystal surfaces.

Minimizing prion risk without compromising the microbial composition of biofilms grown in vivo in a human plaque model

AIMS

To determine whether the stringency of sterilization procedures for biological components of in vivo dental plaque-generating devices based on enamel can be increased to minimize prion risk without compromising natural biofilm composition.

METHODS AND RESULTS

The composition of in vitro biofilms, grown on hypochlorite-treated and untreated autoclaved enamel surfaces, was determined using culture-based methods and checkerboard DNA: DNA hybridization analysis. No differences were found between biofilms recovered from either substrate.

SIGNIFICANCE

Several in situ models allow generation of plaque in the oral cavity, followed by recovery of intact biofilms for experimentation. Approaches allowing plaque formation on natural tooth surfaces are most valuable, but present a possible infection risk to volunteers wearing plaque-collecting devices, particularly with respect to prions. Hypochlorite treatment of biological material, as an adjunct to autoclaving, reduces infection risk without compromising biofilm composition and should be adopted in all future studies using plaque-generating devices incorporating enamel, where there is a potential prion threat, and further investigated in other biological hard tissues.

Subunit structures in hydroxyapatite crystal development in enamel: implications for amelogenesis imperfecta

Previous freeze-etching studies of developing enamel revealed collinear arrays of spherical structures (approximately 50 nM dia) of similar width to the crystals of mature tissue. Concomitant with matrix degradation/processing, spherical structures became less distinct until, coincident with massive matrix loss, only crystal outlines were seen. More recently, using Atomic force microscopy technology, early crystals exhibited topology reminiscent of these collinear spherical structures. After matrix loss these were replaced by similarly sized bands of positive charge density on the crystal surfaces. The data suggest enamel crystals may form from mineral-matrix spherical subunits. Matrix processing may generate mineral nuclei and lead to their fusion and transformation into long apatite crystals. Support for this view derives from the appearance of short crystal segments in amelogenesis imperfecta (hypoplastic AI) or abnormally large crystals alongside 50 nM diameter spherical mineral subunits (hypomaturation AI). Mutation of matrix or processing enzymes leading to defective processing may have impaired mineral initiation, fusion, and subsequent growth.