Undiagnosed dementia in primary care: A record linkage study

BackgroundThe number of people living with dementia is greater than the number with a diagnosis of dementia recorded in primary care. This suggests that a significant number are living with dementia that is undiagnosed. Little is known about this group and there is little quantitative evidence regarding the consequences of diagnosis for people with dementia.ObjectivesThe aims of this study were to (1) describe the population meeting the criteria for dementia but without diagnosis, (2) identify predictors of being diagnosed and (3) estimate the effect of diagnosis on mortality, move to residential care, social participation and well-being.DesignA record linkage study of a subsample of participants (n = 598) from the Cognitive Function and Ageing Study II (CFAS II) (n = 7796), an existing cohort study of the population of England aged ≥ 65 years, with standardised validated assessment of dementia and consent to access medical records.Data sourcesData on dementia diagnoses from each participant’s primary care record and covariate and outcome data from CFAS II.SettingA population-representative cohort of people aged ≥ 65 years from three regions of England between 2008 and 2011.ParticipantsA total of 598 CFAS II participants, which included all those with dementia who consented to medical record linkage (n = 449) and a stratified sample without dementia (n = 149).Main outcome measuresThe main outcome was presence of a diagnosis of dementia in each participant’s primary care record at the time of their CFAS II assessment(s). Other outcomes were date of death, cognitive performance scores, move to residential care, hospital stays and social participation.ResultsAmong people with dementia, the proportion with a diagnosis in primary care was 34% in 2008–11 and 44% in 2011–13. In both periods, a further 21% had a record of a concern or a referral but no diagnosis. The likelihood of having a recorded diagnosis increased with severity of impairment in memory and orientation, but not with other cognitive impairment. In multivariable analysis, those aged ≥ 90 years and those age

Dementia and hearing-aid use: a two-way street

ObjectivesHearing-aid use may reduce risk of dementia, but cognitive impairment makes use more challenging. An observed association between reduced hearing-aid use and incident dementia could reflect either or both of these causal paths. The objective was to examine the effects of each path while minimising contamination between paths.MethodsHealth records data from 380,794 Veterans who obtained hearing aids from the US Veterans Affairs healthcare system were analysed. Analysis 1 (n = 72,180) used multivariable logistic regression to model the likelihood of incident dementia 3.5–5 years post hearing-aid fitting for patients free of dementia and mild cognitive impairment (MCI). Analysis 2 (n = 272,748) modelled the likelihood of being a persistent hearing-aid user at 3 years 2 months after fitting, contrasting subgroups by level of cognitive function at the time of fitting. Analysis time windows were optimized relative to dataset constraints. Models were controlled for available relevant predictors.ResultsThe adjusted OR for incident dementia was 0.73 (95% CI 0.66–0.81) for persistent (versus non-persistent) hearing-aid users. The adjusted OR for hearing-aid use persistence was 0.46 (95% CI 0.43–0.48) in those with pre-existing dementia (versus those remaining free of MCI and dementia).ConclusionSubstantial independent associations are observed in both directions, suggesting that hearing-aid use decreases risk of dementia and that better cognitive function predisposes towards persistent use. Research studying protective effects of hearing-aid use against dementia needs to account for cognitive status. Clinically, hearing devices and hearing care processes must be accessible and usable for all, regardless of their cognitive status

Usefulness of data from magnetic resonance imaging to improve prediction of dementia: population based cohort study

© BMJ Publishing Group Ltd 2015. OBJECTIVE: To determine whether the addition of data derived from magnetic resonance imaging (MRI) of the brain to a model incorporating conventional risk variables improves prediction of dementia over 10 years of follow-up. DESIGN: Population based cohort study of individuals aged ≥65. SETTING: The Dijon magnetic resonance imaging study cohort from the Three-City Study, France. PARTICIPANTS: 1721 people without dementia who underwent an MRI scan at baseline and with known dementia status over 10 years' follow-up. MAIN OUTCOME MEASURE: Incident dementia (all cause and Alzheimer's disease). RESULTS: During 10 years of follow-up, there were 119 confirmed cases of dementia, 84 of which were Alzheimer's disease. The conventional risk model incorporated age, sex, education, cognition, physical function, lifestyle (smoking, alcohol use), health (cardiovascular disease, diabetes, systolic blood pressure), and the apolipoprotein genotype (C statistic for discrimination performance was 0.77, 95% confidence interval 0.71 to 0.82). No significant differences were observed in the discrimination performance of the conventional risk model compared with models incorporating data from MRI including white matter lesion volume (C statistic 0.77, 95% confidence interval 0.72 to 0.82; P=0.48 for difference of C statistics), brain volume (0.77, 0.72 to 0.82; P=0.60), hippocampal volume (0.79, 0.74 to 0.84; P=0.07), or all three variables combined (0.79, 0.75 to 0.84; P=0.05). Inclusion of hippocampal volume or all three MRI variables combined in the conventional model did, however, lead to significant improvement in reclassification measured by using the integrated discrimination improvement index (P=0.03 and P=0.04) and showed increased net benefit in decision curve analysis. Similar results were observed when the outcome was restricted to Alzheimer's disease. CONCLUSIONS: Data from MRI do not significantly improve discrimination performance in prediction of all cause dementia beyond a model incorporating demographic, cognitive, health, lifestyle, physical function, and genetic data. There were, however, statistical improvements in reclassification, prognostic separation, and some evidence of clinical utility

Operationalisation of Mild Cognitive Impairment: A Graphical Approach

A new online tool allows mapping of the different classifications of mild cognitive impairment

Risk factors for dementia in the context of cardiovascular disease: A protocol of an overview of reviews

Background Dementia is a major public health priority. Although there is abundant evidence of an associ-ation between dementia and poor cardiovascular health, findings have been inconsistent and uncertain in identifying which factors increase dementia risk in those with cardiovascular disease. Indeed, multiple variables including sociodemographic, economic, health, lifestyle and education may indicate who is at higher vs. lower dementia risk and could be used in prediction modelling. Therefore, the aim of this review is to synthesise evidence on the key risk factors for dementia in those with a history of cardiovascular disease. Methods This is an overview of reviews protocol, registered on PROSPERO (CRD42021265363). Four electronic databases including MEDLINE, EMBASE, PsycINFO, and the Cochrane Database of Systematic Reviews will be searched. Studies will be included if they are systematic reviews and/or meta-analyses that have investigated the risk of incident dementia (all-cause and subtypes including Alzheimer's disease and vascular dementia) in people with a history of coronary heart disease, heart failure, atrial fibrillation, hypertension, hyperli-pidaemia, and vascular stiffness. Study selection will be completed by two independent researchers according to the eligibility criteria, and conflicts resolved by a third reviewer. References will be exported into Covidence for title and abstract sifting, full-text review, and data extraction. Methodological quality will be assessed using the AMSTAR-2 criteria and confidence of evidence will be assessed using the GRADE classification. This overview of reviews will follow PRISMA guidelines. If there is sufficient homogeneity in the data, the results will be pooled, and a meta-analysis conducted to determine the strength ofassociation between each risk factor and incident all-cause dementia and its subtypes for each cardiovascular diagnoses separately.Discussion We will create a comprehensive summary of the key risk factors linking cardiovascular dis-eases to risk of incident dementia. This knowledge is essential for informing risk predictive model development as well as the development of risk reduction and prevention strategies

Mediterranean diet adherence and cognitive function in older, UK adults: The EPIC-Norfolk study

Background In Mediterranean countries, adherence to a traditional Mediterranean dietary pattern (MedDiet) is associated with better cognitive function and reduced dementia risk. It is unclear if similar benefits exist in non-Mediterranean regions. Objective To examine associations between MedDiet adherence and cognitive function in an older, UK population. To investigate whether associations differed between individuals with high versus low cardiovascular disease (CVD) risk. Design We conducted an analysis in 8009 older individuals with dietary data at Health Check 1 (1993-1997) and cognitive function data at Health Check 3 (2006-2011) of the European Prospective Investigation of Cancer, Norfolk (EPIC-Norfolk). Associations were explored between MedDiet adherence and global and domain specific cognitive test scores and risk of poor cognitive performance in the entire cohort, and when stratified according to CVD risk status. Results Higher MedDiet adherence defined by the Pyramid MedDiet score was associated with better global cognition (β±SE=-0.012±0.002; P<0.001), verbal episodic memory (β±SE=-0.009±0.002; P<0.001), and simple processing speed (β±SE=-0.002±0.001; P=0.013). Lower risk of poor verbal episodic memory (OR(95%CI)=0.784 (0.641,0.959); P=0.018), complex processing speed (OR(95%CI)=0.739 (0.601,0.907); P=0.004), and prospective memory (OR(95%CI)=0.841 (0.724,0.977); P=0.023) was also observed for the highest versus lowest Pyramid MedDiet tertiles. The effect of a one-point increase in Pyramid score on global cognitive function was equivalent to 1.7 fewer years of cognitive ageing. MedDiet adherence defined by the MEDAS score (mapped using both binary and continuous scoring) showed similar, albeit less consistent, associations. In stratified analyses, associations were evident in individuals at higher CVD risk only (P<0.05). Conclusions Higher adherence to the MedDiet is associated with better cognitive function and lower risk of poor cognition in older, UK adults. This evidence underpins the development of interventions to enhance MedDiet adherence, particularly in individuals at higher CVD risk, aiming to reduce the risk of age-related cognitive decline in non-Mediterranean populations

Cardiovascular disease, associated risk factors, and risk of dementia: An umbrella review of meta-analyses

Introduction: Cardiovascular diseases (CVDs) have been associated with an increased risk of dementia; yet the evidence is mixed. This review critically appraises and synthesises current evidence exploring associations between dementia risk and CVD and their risk factors, including coronary heart disease, heart failure, atrial fibrillation, hypertension, hyperlipidaemia, and arterial stiffness. Methods: MEDLINE, Embase, PsycINFO, and the Cochrane Database of Systematic Reviews were searched to identify systematic reviews with meta-analyses investigating the association between at least one of the CVDs of interest and dementia risk. The Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Systematic Reviews was used to assess methodological quality. Results: Twenty-five meta-analyses published between 2007 and 2021 were included. Studies largely consisted of cohorts from North America and Europe. Findings were variable, with coronary heart disease, heart failure, and atrial fibrillation consistently associated with increased risk for all-cause dementia, but results were inconsistent for Alzheimer's disease. Hypertension was more frequently associated with dementia during mid-life compared to late life. Findings concerning cholesterol were complex, and while results were inconsistent for low-density lipoprotein cholesterol and total cholesterol, there appeared to be no associations between triglycerides and high-density lipoprotein cholesterol. All meta-analyses investigating hypercholesterolaemia showed significant increases in dementia risk. There was a paucity of research on the association between arterial stiffness and dementia risk. Conclusion: Targeted CVD dementia prevention strategies could reduce dementia prevalence. Future research should determine the underpinning mechanisms linking heart and brain health to determine the most effective strategies for dementia risk reduction in CVD populations

Behavioural and psychological symptoms in the older population without dementia - relationship with socio-demographics, health and cognition

<p>Abstract</p> <p>Background</p> <p>Behavioural and psychological symptoms are associated with dementia, but are also present in a significant number of the older population without dementia. Here we explore the distribution of behavioural and psychological symptoms in the population without dementia, and their relationship with domains and severity of health and cognitive impairment.</p> <p>Methods</p> <p>The Medical Research Council Cognitive Function and Ageing Study is a two-phase longitudinal study of ageing representative of the population aged 65 and over of England and Wales. A subsample of 1781 participants without a study diagnosis of dementia was included in this study. Information on symptoms including depression, apathy, anxiety, feelings of persecution, hallucination, agitated behaviour, elation, irritability, sleep problems, wandering, confabulation and misidentification, cognitive function, health related factors and socio-demographic information was extracted from interviews with participants and knowledgeable informants. Participants were classified according to the Mini-Mental State Examination and by criteria for subtypes of mild cognitive impairment (MCI). The prevalence of behavioural and psychological symptoms and associations with cognitive function, health and socio-demographics was examined. Co-occurrence of symptoms was tested using factor analysis.</p> <p>Results</p> <p>Most symptoms were reported more frequently in those with more severe cognitive impairment. Subjective memory complaints were the strongest independent predictor of reported symptoms, and most were reported more often in those classified as having MCI than in those with cognitive impairments that did not meet the MCI criteria. The pattern of co-occurrence of symptoms is similar to that seen in dementia.</p> <p>Conclusions</p> <p>Our results highlight that behavioural and psychological symptoms are prevalent in the cognitively impaired older population, and partly explain the variation observed in previous cohorts of individuals with MCI. Behavioural and psychological symptoms offer a target for intervention and so are an important consideration in the assessment of cognitively impaired older people.</p