Potentially Modifiable Risk Factors for Dementia and Mild Cognitive Impairment: An Umbrella Review and Meta-Analysis.

INTRODUCTION: The prevalence of mild and major neurocognitive disorders (NCDs), also referred to as mild cognitive impairment and dementia, is rising globally. The prevention of NCDs is a major global public health interest. We sought to synthesize the literature on potentially modifiable risk factors for NCDs. METHODS: We conducted an umbrella review using a systematic search across multiple databases to identify relevant systematic reviews and meta-analyses. Eligible reviews examined potentially modifiable risk factors for mild or major NCDs. We used a random-effects multi-level meta-analytic approach to synthesize risk ratios for each risk factor while accounting for overlap in the reviews. We further examined risk factors for major NCD due to two common etiologies: Alzheimer's disease and vascular dementia. RESULTS: A total of 45 reviews with 212 meta-analyses were synthesized. We identified fourteen broadly defined modifiable risk factors that were significantly associated with these disorders: alcohol consumption, body weight, depression, diabetes mellitus, diet, hypertension, less education, physical inactivity, sensory loss, sleep disturbance, smoking, social isolation, traumatic brain injury, and vitamin D deficiency. All 14 factors were associated with the risk of major NCD, and five were associated with mild NCD. We found considerably less research for vascular dementia and mild NCD. CONCLUSION: Our review quantifies the risk associated with 14 potentially modifiable risk factors for mild and major NCDs, including several factors infrequently included in dementia action plans. Prevention strategies should consider approaches that reduce the incidence and severity of these risk factors through health promotion, identification, and early management.

Core Outcome Sets for Medium-Chain Acyl-CoA Dehydrogenase Deficiency and Phenylketonuria.

BACKGROUND: Evidence to guide treatment of pediatric medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency and phenylketonuria (PKU) is fragmented because of large variability in outcome selection and measurement. Our goal was to develop core outcome sets (COSs) for these diseases to facilitate meaningful future evidence generation and enhance the capacity to compare and synthesize findings across studies. METHODS: Parents and/or caregivers, health professionals, and health policy advisors completed a Delphi survey and participated in a consensus workshop to select core outcomes from candidate lists of outcomes for MCAD deficiency and PKU. Delphi participants rated the importance of outcomes on a nine-point scale (1-3: not important, 4-6: important but not critical, 7-9: critical). Candidate outcomes were progressively narrowed down over 3 survey rounds. At the workshop, participants evaluated the remaining candidate outcomes using an adapted nominal technique, open discussion, and voting. After the workshop, we finalized the COSs and recommended measurement instruments for each outcome. RESULTS: There were 85, 61, and 53 participants across 3 Delphi rounds, respectively. The candidate core outcome lists were narrowed down to 20 outcomes per disease to be discussed at the consensus workshop. Voting by 18 workshop participants led to COSs composed of 8 and 9 outcomes for MCAD deficiency and PKU, respectively, with measurement recommendations. CONCLUSIONS: These are the first known pediatric COSs for MCAD deficiency and PKU. Adoption in future studies will help to ensure best use of limited research resources to ultimately improve care for children with these rare diseases.

Outcomes in pediatric studies of medium-chain acyl-coA dehydrogenase (MCAD) deficiency and phenylketonuria (PKU): a review.

BACKGROUND: Inherited metabolic diseases (IMDs) are a group of individually rare single-gene diseases. For many IMDs, there is a paucity of high-quality evidence that evaluates the effectiveness of clinical interventions. Clinical effectiveness trials of IMD interventions could be supported through the development of core outcome sets (COSs), a recommended minimum set of standardized, high-quality outcomes and associated outcome measurement instruments to be incorporated by all trials in an area of study. We began the process of establishing pediatric COSs for two IMDs, medium-chain acyl-CoA dehydrogenase (MCAD) deficiency and phenylketonuria (PKU), by reviewing published literature to describe outcomes reported by authors, identify heterogeneity in outcomes across studies, and assemble a candidate list of outcomes. METHODS: We used a comprehensive search strategy to identify primary studies and guidelines relevant to children with MCAD deficiency and PKU, extracting study characteristics and outcome information from eligible studies including outcome measurement instruments for select outcomes. Informed by an established framework and a previously published pediatric COS, outcomes were grouped into five, mutually-exclusive, a priori core areas: growth and development, life impact, pathophysiological manifestations, resource use, and death. RESULTS: For MCAD deficiency, we identified 83 outcomes from 52 articles. The most frequently represented core area was pathophysiological manifestations, with 33 outcomes reported in 29/52 articles (56%). Death was the most frequently reported outcome. One-third of outcomes were reported by a single study. The most diversely measured outcome was cognition and intelligence/IQ for which eight unique measurement instruments were reported among 14 articles. For PKU, we identified 97 outcomes from 343 articles. The most frequently represented core area was pathophysiological manifestations with 31 outcomes reported in 281/343 articles (82%). Phenylalanine concentration was the most frequently reported outcome. Sixteen percent of outcomes were reported by a single study. Similar to MCAD deficiency, the most diversely measured PKU outcome was cognition and intelligence/IQ with 39 different instruments reported among 82 articles. CONCLUSIONS: Heterogeneity of reported outcomes and outcome measurement instruments across published studies for both MCAD deficiency and PKU highlights the need for COSs for these diseases, to promote the use of meaningful outcomes and facilitate comparisons across studies.

Health Care for Mitochondrial Disorders in Canada: A Survey of Physicians.

BACKGROUND: An improved understanding of diagnostic and treatment practices for patients with rare primary mitochondrial disorders can support benchmarking against guidelines and establish priorities for evaluative research. We aimed to describe physician care for patients with mitochondrial diseases in Canada, including variation in care. METHODS: We conducted a cross-sectional survey of Canadian physicians involved in the diagnosis and/or ongoing care of patients with mitochondrial diseases. We used snowball sampling to identify potentially eligible participants, who were contacted by mail up to five times and invited to complete a questionnaire by mail or internet. The questionnaire addressed: personal experience in providing care for mitochondrial disorders; diagnostic and treatment practices; challenges in accessing tests or treatments; and views regarding research priorities. RESULTS: We received 58 survey responses (52% response rate). Most respondents (83%) reported spending 20% or less of their clinical practice time caring for patients with mitochondrial disorders. We identified important variation in diagnostic care, although assessments frequently reported as diagnostically helpful (e.g., brain magnetic resonance imaging, MRI/MR spectroscopy) were also recommended in published guidelines. Approximately half (49%) of participants would recommend "mitochondrial cocktails" for all or most patients, but we identified variation in responses regarding specific vitamins and cofactors. A majority of physicians recommended studies on the development of effective therapies as the top research priority. CONCLUSIONS: While Canadian physicians' views about diagnostic care and disease management are aligned with published recommendations, important variations in care reflect persistent areas of uncertainty and a need for empirical evidence to support and update standard protocols.

Les soins de santé prodigués au Canada à des individus atteints de troubles mitochondriaux : une enquête menée auprès de médecins. Contexte: Dans le cas de patients atteints de troubles mitochondriaux rares, il est permis de croire qu'une meilleure compréhension des pratiques en matière de diagnostic et de traitement peut contribuer, au moyen des lignes directrices, à l'étalonnage et à l'établissement de priorités en ce qui regarde la recherche évaluative. Notre intention a été de décrire les soins prodigués au Canada par des médecins, notamment leur variabilité, dans le cas de ces patients. Méthodes: Pour ce faire, nous avons effectué une enquête transversale auprès de médecins canadiens qui posent des diagnostics de troubles mitochondriaux et qui prodiguent des soins continus aux patients qui en sont atteints. À cet effet, nous avons fait appel à la méthode d'enquête dite « en boule de neige ¼ (snowball sampling) afin d'identifier des participants possiblement admissibles. Ces derniers ont été ensuite contactés par la poste, et ce, à cinq reprises au maximum. Ils ont été invités à remplir un questionnaire et à le retourner par la poste ou en ligne. Ce questionnaire abordait les aspects suivants : leur expérience personnelle à titre de prestataire de soins ; leurs pratiques en matière de diagnostic et de traitement ; les défis se présentant à eux au moment d'avoir accès à des tests ou à des traitements ; et finalement leurs points de vue en ce qui regarde les priorités de la recherche. Résultats: Dans le cadre de cette enquête, nous avons reçu 58 réponses, ce qui représente un taux de 52 %. Une majorité de répondants (83 %) ont indiqué allouer 20 % ou moins de leur temps de pratique clinique aux soins de patients atteints de ces troubles. Nous avons également noté d'importantes variations concernant les soins et les diagnostics, et ce, même si les outils d'évaluation fréquemment considérés utiles sur le plan diagnostic (p. ex. : des IRM du cerveau/la spectroscopie par RM) étaient également recommandés dans des lignes directrices déjà publiées. Environ la moitié de nos répondants (49 %) recommanderaient volontiers un « cocktail ¼ de vitamines pour tous leurs patients ou la plupart d'entre eux. Quand il est question de vitamines spécifiques et de cofacteurs, nous avons cependant identifié une variation dans leurs réponses. Interrogés quant à la priorité numéro un en matière de recherche, une majorité de répondants a dit recommander la poursuite d'études portant sur la mise sur pied de traitements thérapeutiques efficaces. Conclusions: Bien que les points de vue de ces médecins canadiens en ce qui regarde les diagnostics et la prise en charge des troubles mitochondriaux soient en phase avec des recommandations publiées, d'importantes variations reflètent la persistance d'aspects incertains ainsi qu'un besoin de données empiriques afin de renforcer et de mettre à jour les protocoles de rééférence.