Accuracy of general hospital dementia diagnoses in England: Sensitivity, specificity, and predictors of diagnostic accuracy 2008-2016

Slow gut transit increases the risk of Alzheimer's disease: An integrated study of the bi-national cohort in South Korea and Japan and Alzheimer's disease model mice

INTRODUCTION

Although the association between Alzheimer's disease (AD) and constipation is controversial, its causality and underlying mechanisms remain unknown.

OBJECTIVES

To investigate the potential association between slow gut transit and AD using epidemiological data and a murine model.

METHODS

We conducted a bi-national cohort study in South Korea (discovery cohort, N=3,130,193) and Japan (validation cohort, N=4,379,285) during the pre-observation period to determine the previous diagnostic history (2009-2010) and the follow-up period (2011-2021). To evaluate the causality, we induced slow gut transit using loperamide in 5xFAD transgenic mice. Changes in amyloid-beta (Aβ) and other markers were examined using ELISA, qRT-PCR, RNA-seq, and behavioral tests.

RESULTS

Constipation was associated with an increased risk of AD in the discovery cohort (hazard ratio, 2.04; 95% confidence interval [CI], 2.01-2.07) and the validation cohort (hazard ratio; 2.82; 95% CI, 2.61-3.05). We found that loperamide induced slower gut transit in 5xFAD mice, increased Aβ and microglia levels in the brain, increased transcription of genes related to norepinephrine secretion and immune responses, and decreased the transcription of defense against bacteria in the colonic tissue.

CONCLUSION

Impaired gut transit may contribute to AD pathogenesis via the gut-brain axis, thus suggesting a cyclical relationship between intestinal barrier disruption and Aβ accumulation in the brain. We propose that gut transit or motility may be a modifiable lifestyle factor in the prevention of AD, and further clinical investigations are warranted.

Identifying individuals at high risk for dementia in primary care: Development and validation of the DemRisk risk prediction model using routinely collected patient data

INTRODUCTION

Health policy in the UK and globally regarding dementia, emphasises prevention and risk reduction. These goals could be facilitated by automated assessment of dementia risk in primary care using routinely collected patient data. However, existing applicable tools are weak at identifying patients at high risk for dementia. We set out to develop improved risk prediction models deployable in primary care.

METHODS

Electronic health records (EHRs) for patients aged 60-89 from 393 English general practices were extracted from the Clinical Practice Research Datalink (CPRD) GOLD database. 235 and 158 practices respectively were randomly assigned to development and validation cohorts. Separate dementia risk models were developed for patients aged 60-79 (development cohort n = 616,366; validation cohort n = 419,126) and 80-89 (n = 175,131 and n = 118,717). The outcome was incident dementia within 5 years and more than 60 evidence-based risk factors were evaluated. Risk models were developed and validated using multivariable Cox regression.

RESULTS

The age 60-79 development cohort included 10,841 incident cases of dementia (6.3 per 1,000 person-years) and the age 80-89 development cohort included 15,994 (40.2 per 1,000 person-years). Discrimination and calibration for the resulting age 60-79 model were good (Harrell's C 0.78 (95% CI: 0.78 to 0.79); Royston's D 1.74 (1.70 to 1.78); calibration slope 0.98 (0.96 to 1.01)), with 37% of patients in the top 1% of risk scores receiving a dementia diagnosis within 5 years. Fit statistics were lower for the age 80-89 model but dementia incidence was higher and 79% of those in the top 1% of risk scores subsequently developed dementia.

CONCLUSION

Our models can identify individuals at higher risk of dementia using routinely collected information from their primary care record, and outperform an existing EHR-based tool. Discriminative ability was greatest for those aged 60-79, but the model for those aged 80-89 may also be clinical useful.

Post-diagnosis smoking habit change and incident dementia in cancer survivors

INTRODUCTION

Many individuals change their smoking habits after cancer diagnosis. We aimed to evaluate the association of post-diagnosis smoking habit change with incident dementia in cancer survivors.

METHODS

We identified 558,127 individuals who were diagnosed with cancer at age ≥ 20 and survived for ≥ 3 years. Participants were classified into four groups: (1) sustained non-smokers, (2) initiators/relapsers, (3) quitters, and (4) continuing smokers. Dementia risk in each group was assessed using a cause-specific Cox model.

RESULTS

After cancer diagnosis, 2.3% of pre-diagnosis non-smokers initiated/relapsed into smoking, while 51.7% of pre-diagnosis smokers quit smoking. Compared to sustained non-smokers, multivariable-adjusted risk of dementia was 29% higher among initiators/relapsers, 11% higher among quitters, and 31% higher among continuing smokers. Compared to continuing smokers, the risk was 15% lower among quitters.

DISCUSSION

In cancer survivors, smoking initiation/relapse was associated with increased risk of dementia, whereas smoking cessation was associated with decreased risk of dementia.

HIGHLIGHTS

Approximately half of pre-diagnosis smokers quit smoking after a cancer diagnosis. Smoking cessation was associated with a 15% reduced risk of dementia. More than 2% of pre-diagnosis non-smokers initiated or relapsed into smoking after a cancer diagnosis. Smoking initiation/relapse was associated with a 29% elevated risk of dementia.

Hospital admissions for dementia in the Brazilian public health system over the last decade

OBJECTIVE

The rise in dementia prevalence, particularly in lower- and middle-income countries (LMIC), places a significant burden on healthcare systems. However, comprehensive data on dementia hospital admissions are scarce.

METHODS

We analyzed admission rates for dementia, cost of hospital admissions, lengths of hospital stay, and in-hospital deaths in 2010 and 2019 in Brazil.

RESULTS

Admission rates declined from 19.7/100,000 inhabitants in 2010 to 14.6/100,000 in 2019. In-hospital mortality increased from 3.9% in 2010 to 8.8% in 2019, particularly for short-term stays. Although 9.6% of hospital admissions occurred in regions with lower economic power in 2010 and 10.4% in 2019, these regions had higher mortality, reaching 4.3% of in-hospital deaths in 2010 and 9.3% in 2019.

CONCLUSION

The observed trends, alongside sex and regional disparities, underscore the need for targeted investment in healthcare infrastructure and training to improve dementia care in LMIC.

Highlights

The rate of hospital admissions for dementia was similar in 2010 and 2019 in Brazil.The cost per hospital admission in 2010 decreased by 38.5% compared with 2019.There was an increase in short-term hospital stays for dementia in 2019 compared to 2010, accompanied by an increase in mortality rates for these short-term stays.While hospital admissions for dementia decreased in men and increased in women, the in-hospital mortality due to dementia increased for both sexes.

A Systematic Review on the Evidence of Misdiagnosis in Dementia and Its Impact on Accessing Dementia Care

BACKGROUND

Whilst there is a drive to increase diagnosis rates in dementia, there is a lack of attention on getting a correct and timely subtype diagnosis. For people with a rarer subtype of dementia, getting the correct diagnosis, and subsequent care, might be more difficult than for people aged 65+ presenting with the more common symptoms of Alzheimer's disease dementia. Thus, the aim of this mixed-method systematic review was to synthesise the evidence base on misdiagnosis of dementia.

METHODS

Misdiagnosis in dementia was defined as either receiving an initial incorrect dementia subtype diagnosis or receiving an incorrect non-dementia diagnosis. Post-mortem assessments of subtype diagnosis were excluded. Nine databases were searched in June 2023, with screening of titles and abstracts and consequent full texts completed independently by two researchers. Findings were synthesised using narrative synthesis.

RESULTS

Twenty studies were included. Studies were categorised into four themes: (i) Factors associated with delayed diagnosis or misdiagnosis; (ii) Difficulties related to the diagnostic process; (iii) Economic consequences of misdiagnosis; and (iv) Experiences of delayed diagnosis or help-seeking. People with Lewy Body dementia or behavioural variant fronto-temporal dementia were found to experience longer diagnosis times and often incorrect initial diagnoses. Whilst evidence is limited regarding the economic impacts, evidence from the US points towards increased economic costs of misdiagnosis.

CONCLUSIONS

There is an urgent need to investigate the rates and emotional and economic impacts of misdiagnosis on people with dementia, their carers, and the health and social care system. Advancing the evidence base is crucial to reduce misdiagnosis and inform clinical practice.

Association between coffee and tea consumption and the risk of dementia in individuals with hypertension: a prospective cohort study

Many studies have shown that drinking coffee and tea may be associated with the risk of hypertension and dementia. Limited research exists on their impact on dementia risk in hypertensive patients. This study aimed to determine the association between coffee and tea consumption and the risk of dementia development in hypertensive population by utilizing Cox proportional risk modeling with 453,913 participants from a UK biobank. Our findings reveal a J-shaped and U-shaped association between the risk of all-cause dementia and the consumption of coffee and tea respectively in hypertensive people. The hypertensive patients who drink 0.5-1 cup of coffee or 4-5 cups of tea per day have the lowest risk of dementia. A U-shaped relationship was observed between daily caffeine consumption and the risk of developing all-cause dementia and vascular dementia in the hypertensive population. Furthermore, the significant association between the amount of coffee and tea consumed and the risk of all-cause and vascular dementia were more likely to be found in hypertensive patients than in the non-hypertensive population.

Association of neuroticism with incident dementia, neuroimaging outcomes, and cognitive function

INTRODUCTION

Higher neuroticism might be associated with dementia risk. Here we investigated modification by genetic predisposition to dementia, mediation by mental health and vascular conditions, neuroimaging outcomes, and cognitive function.

METHODS

Cox proportional-hazards models were used to assess the association between neuroticism score and incident dementia over up to 15 years in 1,74,164 participants. Cross-sectional analyses on dementia-related neuroimaging outcomes and cognitive function were conducted in 39,459 dementia-free participants.

RESULTS

Higher neuroticism was associated with an 11% higher risk of incident dementia, especially vascular dementia (15% higher risk), regardless of genetic predisposition to dementia. Mental and vascular conditions mediated the association of neuroticism with all-cause dementia and vascular dementia. Neuroticism was associated with higher cerebrovascular pathology, lower gray matter volume, and worse function across multiple cognitive domains.

DISCUSSION

Neuroticism could represent a risk factor for dementia, and vascular and mental health might drive these associations.

HIGHLIGHTS

Neuroticism was associated with an increased risk of incident all-cause dementia, particularly vascular dementia. Associations were not modified by genetic predisposition to dementia. Associations were largely mediated by mental and vascular conditions. Neuroticism was associated with increased cerebrovascular pathology and lower gray matter volume. Neuroticism was associated with worse function across multiple cognitive domains.

Association between adult education, brain volume and dementia risk: longitudinal cohort study of UK Biobank participants

Less childhood education is a potentially modifiable risk factor for developing incident dementia but it is not known if education in later life is protective. We sought to add to previous work by testing the association between adult education and brain volume as well as exploring the impact of continuing adult education versus intermittent participation. We used data from participants of the UK Biobank cohort, with no prevalent dementia who were asked about adult education participation at baseline and at follow-up. Dementia status was ascertained from self-report or electronic health records. Cox proportional hazards models were built to estimate hazard ratios (HRs) between participation in adult education and dementia risk. In 499,337 participants aged between 40 and 69 at baseline with 13.2 years mean follow-up, in analyses adjusted for age, sex, education, deprivation, ethnicity, hypertension, diabetes, ethnicity, obesity, smoking, alcohol use, physical inactivity and social isolation, we replicated previous findings of a protective effect of adult education on dementia risk (HR 0.82, 95% CI 0.74-0.90, P < 0.001), and showed a trend towards protection against dementia if adult education was continued rather than intermittent. Additionally, adult education did not impact on total brain volume (coefficient - 657.4, 95% CI - 2795.1 to 1480.3, P = 0.547) but it was associated with increased hippocampal volume (coefficient 33.9, 95% CI 8.9 to 59.0, P = 0.008) indicating a potential mechanism for protection against dementia. We have added evidence indicating that continuing adult education participation may be beneficial, although numbers for this analysis were very small. Analysis of brain volume indicated that adult education may have a protective effect by preserving hippocampal size or slowing volume loss, in line with the cognitive reserve hypothesis.

Systemic inflammation, lifestyle behaviours and dementia: A 10-year follow-up investigation

Objectives

Lifestyle behaviours have been linked to dementia incidence, but their cumulative impact on dementia and the underlying mechanisms remain poorly understood. This study investigated the association of co-occurring lifestyle behaviours with dementia incidence and the mediating role of systemic inflammation in this association.

Methods

The sample comprised 3131 participants (55.2% female) from the English Longitudinal Study of Ageing aged 52-92 years at baseline (2008/09). Self-reported baseline lifestyle behaviours (alcohol intake, fruit and vegetable consumption, smoking, physical activity, sleep duration, social engagement, and cognitive activity) were summed to derive an index of lifestyle behaviours, ranging from 0 to 7, with higher scores denoting a higher number of health-risk behaviours. Incident dementia cases (n = 130, 4.2%) were identified through doctor-diagnosed dementia, informant interviews, and health records between 2014/15 and 2018/19. Systemic inflammation was measured through fasting plasma concentrations of C-reactive protein in 2012/13.

Results

Binary logistic regression models indicated that the odds of subsequent dementia increased by 1.19 for each additional health-risk behaviour (95% confidence intervals: 1.04, 1.37, p = 0.014) after adjusting for age, sex, ethnicity, wealth, education, marital status, body mass index, coronary heart disease, hypertension, stroke, and depression. However, this association was not mediated by C-reactive protein.

Conclusions

Co-occurring health-risk behaviours were associated with higher dementia incidence up to 10 years later, underscoring the importance of modifying health-risk behaviours for the prevention of dementia. Systemic inflammation did not explain the association between behaviours and dementia.

Association of MAFLD and MASLD with all-cause and cause-specific dementia: a prospective cohort study

BACKGROUND

Liver disease and dementia are both highly prevalent and share common pathological mechanisms. We aimed to investigate the associations between metabolic dysfunction-associated fatty liver disease (MAFLD), metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of all-cause and cause-specific dementia.

METHODS

We conducted a prospective study with 403,506 participants from the UK Biobank. Outcomes included all-cause dementia, Alzheimer's disease, and vascular dementia. Multivariable Cox proportional hazards models were used for analyses.

RESULTS

155,068 (38.4%) participants had MAFLD, and 111,938 (27.7%) had MASLD at baseline. During a median follow-up of 13.7 years, 5,732 participants developed dementia (2,355 Alzheimer's disease and 1,274 vascular dementia). MAFLD was associated with an increased risk of vascular dementia (HR 1.32 [95% CI 1.18-1.48]) but a reduced risk of Alzheimer's disease (0.92 [0.84-1.0]). Differing risks emerged among MAFLD subtypes, with the diabetes subtype increasing risk of all-cause dementia (1.8 [1.65-1.96]), vascular dementia (2.95 [2.53-3.45]) and Alzheimer's disease (1.46 [1.26-1.69]), the lean metabolic disorder subtype only increasing vascular dementia risk (2.01 [1.25-3.22]), whereas the overweight/obesity subtype decreasing risk of Alzheimer's disease (0.83 [0.75-0.91]) and all-cause dementia (0.9 [0.84-0.95]). MASLD was associated with an increased risk of vascular dementia (1.24 [1.1-1.39]) but not Alzheimer's disease (1.0 [0.91-1.09]). The effect of MAFLD on vascular dementia was consistent regardless of MASLD presence, whereas associations with Alzheimer's disease were only present in those without MASLD (0.78 [0.67-0.91]).

CONCLUSIONS

MAFLD and MASLD are associated with an increased risk of vascular dementia, with subtype-specific variations observed in dementia risks. Further research is needed to refine MAFLD and SLD subtyping and explore the underlying mechanisms contributing to dementia risk.

Hidden dangers: Does multisensory impairments accompanying visual impairment increase dementia risk

BACKGROUND

Growing evidence suggests that sensory impairment, particularly in the form of visual impairment, may contribute to the development of dementia. However, it remains unclear whether experiencing concurrent visual impairment in combination with other types of multisensory impairments may further increase this risk.

METHODS

The study used data from the UK Biobank cohort study, which recruited 500,000 adults. With meticulous screening procedures in place, individuals with visual impairment, hearing impairment, and oral health issues were identified for further follow-up evaluations. A multivariable regression analysis was conducted to investigate the relationship between multisensory impairments concurrent with visual impairment and cognitive function. Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals to evaluate the association between multisensory impairments concurrent with visual impairment and dementia risk.

RESULTS

Subjects experiencing multisensory impairments concurrent with visual impairment demonstrated a negative association with cognitive function. Notably, individuals who have both vision and hearing impairments had a significantly higher risk of developing dementia (HR 1.28, 95% CI [1.01-1.63]). Additionally, individuals who experience vision impairment and oral health issues simultaneously were also at higher risk for dementia (HR 1.61, 95% CI [1.32-1.97]). Furthermore, the risk of dementia among individuals with vision impairment, hearing impairment, and oral health issues further escalated to an even higher level (HR 1.63, 95% CI [1.19-2.24]).

CONCLUSIONS

The correlation between the presence of multisensory impairments concurrent with visual impairment and cognitive decline is highly significant. Those with multisensory impairments concurrent with visual impairment are at a significantly increased risk of developing dementia.

Predictors of primary care psychological therapy outcomes for depression and anxiety in people living with dementia: evidence from national healthcare records in England

BACKGROUND

Psychological therapies can be effective in reducing symptoms of depression and anxiety in people living with dementia (PLWD). However, factors associated with better therapy outcomes in PLWD are currently unknown.

AIMS

To investigate whether dementia-specific and non-dementia-specific factors are associated with therapy outcomes in PLWD.

METHOD

National linked healthcare records were used to identify 1522 PLWD who attended psychological therapy services across England. Associations between various factors and therapy outcomes were explored.

RESULTS

People with frontotemporal dementia were more likely to experience reliable deterioration in depression/anxiety symptoms compared with people with vascular dementia (odds ratio 2.98, 95% CI 1.08-8.22; P = 0.03) or Alzheimer's disease (odds ratio 2.95, 95% CI 1.15-7.55; P = 0.03). Greater depression severity (reliable recovery: odds ratio 0.95, 95% CI 0.92-0.98, P < 0.001; reliable deterioration: odds ratio 1.73, 95% CI 1.04-2.90, P = 0.04), lower work and social functioning (recovery: odds ratio 0.98, 95% CI 0.96-0.99, P = 0.002), psychotropic medication use (recovery: odds ratio 0.67, 95% CI 0.51-0.90, P = 0.01), being of working age (recovery: odds ratio 2.03, 95% CI 1.10-3.73, P = 0.02) and fewer therapy sessions (recovery: odds ratio 1.12, 95% CI 1.09-1.16, P < 0.001) were associated with worse therapy outcomes in PLWD.

CONCLUSIONS

Dementia type was generally not associated with outcomes, whereas clinical factors were consistent with those identified for the general population. Additional support and adaptations may be required to improve therapy outcomes in PLWD, particularly in those who are younger and have more severe depression.

Understanding health service utilisation patterns for care home residents during the COVID-19 pandemic using routinely collected healthcare data

BACKGROUND

Healthcare in care homes during the COVID-19 pandemic required a balance, providing treatment while minimising exposure risk. Policy for how residents should receive care changed rapidly throughout the pandemic. A lack of accessible data on care home residents over this time meant policy decisions were difficult to make and verify. This study investigates common patterns of healthcare utilisation for care home residents in relation to COVID-19 testing events, and associations between utilisation patterns and resident characteristics.

METHODS

Datasets from County Durham and Darlington NHS Foundation Trust including secondary care, community care and a care home telehealth app are linked by NHS number used to define daily healthcare utilisation sequences for care home residents. We derive four 10-day sets of sequences related to Pillar 1 COVID-19 testing; before [1] and after [2] a resident's first positive test and before [3] and after [4] a resident's first test. These sequences are clustered, grouping residents with similar healthcare patterns in each set. Association of individual characteristics (e.g. health conditions such as diabetes and dementia) with healthcare patterns are investigated.

RESULTS

We demonstrate how routinely collected health data can be used to produce longitudinal descriptions of patient care. Clustered sequences [1,2,3,4] are produced for 3,471 care home residents tested between 01/03/2020-01/09/2021. Clusters characterised by higher levels of utilisation were significantly associated with higher prevalence of diabetes. Dementia is associated with higher levels of care after a testing event and appears to be correlated with a hospital discharge after a first test. Residents discharged from inpatient care within 10 days of their first test had the same mortality rate as those who stayed in hospital.

CONCLUSION

We provide longitudinal, resident-level data on care home resident healthcare during the COVID-19 pandemic. We find that vulnerable residents were associated with higher levels of healthcare usage despite the additional risks. Implications of findings are limited by the challenges of routinely collected data. However, this study demonstrates the potential for further research into healthcare pathways using linked, routinely collected datasets.

Role of cardiovascular health factors in mediating social inequalities in the incidence of dementia in the UK: two prospective, population-based cohort studies

Background

The contribution of modifiable risk factors to social inequalities in dementia, observed in longitudinal studies, remains unclear. We aimed to quantify the role of cardiovascular health factors, assessed using Life's Essential 8 (LE8) score, in mediating social inequalities in incidence of dementia and, for comparison, in incidence of stroke, coronary heart disease, and mortality.

Methods

In this prospective, population-based cohort study, we collected data from the UK Whitehall II Study and UK Biobank databases. Participants were included if data were available on SEP, outcomes and LE8 (smoking, physical activity, diet, body mass index, blood pressure, fasting blood glucose, lipid levels, sleep duration). The primary outcome was incident dementia and secondary outcomes were stroke, coronary heart disease, and mortality. Outcomes were derived from electronic healthcare records. Socioeconomic position (SEP) was measured by occupation in Whitehall II and education in UK Biobank. Counterfactual mediation analysis was used to quantify the extent to which LE8 score explained the associations of SEP with all outcomes. Analyses involved Cox regression, accelerated failure time models, and linear regression; and were adjusted for age, sex, and ethnicity.

Findings

Between 10.09.1985 and 29.03.1988, a total of 9688 participants (mean age ± SD 44.9 ± 6.0; 67% men) from the Whitehall II study, and between 19.12.2006 and 01.10.2010, 278,215 participants (mean age ± SD 56.0 ± 8.1; 47% men) from the UK Biobank were included. There were 606 and 4649 incident dementia cases over a median (interquartile range) follow-up of 31.7 (31.1-32.7) and 13.5 (12.7-14.1) years respectively in Whitehall II and UK Biobank. In Whitehall II, the hazard ratio was 1.85 [95% CI 1.42, 2.32] for the total effect of SEP on dementia and 1.20 [1.12, 1.28] for the indirect effect via the LE8, the proportion mediated being 36%. In UK Biobank, the total effect of SEP on dementia was 1.65 [1.54, 1.78]; the indirect effect was 1.11 [1.09, 1.12], and the proportion mediated was 24%. The proportions mediated for stroke, coronary heart disease, and mortality were higher, ranging between 34% and 63% in Whitehall II and between 36% and 50% in UK Biobank.

Interpretation

In two well-characterised cohort studies, up to one third of the social inequalities in incidence of dementia was attributable to cardiovascular health factors. Promotion of cardiovascular health in midlife may contribute to reducing social inequalities in risk of dementia, in addition to cardiovascular diseases and all-cause mortality. This study used adult measures of SEP, further research is warranted using lifecourse measures of SEP.

Funding

NIH (RF1AG062553).

Dementia prevalence among hospitalized older patients: a multicenter study in Iran

Dementia poses a significant societal and health challenge in the 21st century, with many hospitalized patients experiencing dementia without a documented diagnosis.

Objective

To evaluate the prevalence of dementia and its associated risk factors among older patients admitted to hospitals.

Methods

The study included older patients (≥ 60 years) admitted to medical departments of a general hospital in three major Iranian cities. Researchers utilized the Activities of Daily Living-Instrumental Activities of Daily Living (ADL-IADL) scale, the Geriatric Depression Scale (GDS), the Mini-Cog test, the 4 A's test (4AT), and the Abbreviated Mental Test Score (AMTS). Among the 420 recruited older inpatients, 228 (54.3%) were female.

Results

The mean age of participants was 71.39 years (standard deviation ±7.95), with 30.7% diagnosed with major neurocognitive disorder (dementia). The likelihood of dementia exhibited statistically significant correlations with gender, age, number of children, and occupation.

Conclusions

Screening older individuals for cognitive impairment upon hospital admission holds the potential to prevent adverse outcomes and enhance the quality of treatment for patients concurrently dealing with dementia.

Age at cardiovascular disease onset, dementia risk, and the role of lifestyle factors

INTRODUCTION

We first examined the role of age at cardiovascular disease (CVD) onset for incident dementia, and then examined whether lifestyle factors at guideline-recommended levels in individuals with CVD mitigates dementia risk.

METHODS

We used population-based data (Whitehall II: n = 10,308/baseline 1985-1988/examinations every 4-5 years). Lifestyle factors (non-smoking, body mass index [BMI], physical activity, diet) were extracted post-CVD.

RESULTS

Over a median of 31.6 years, 3275 (32.1%) developed CVD. At age 70, risk of dementia was higher in individuals with CVD onset before (hazard ratio [HR] of incident dementia for participants with CVD before age 60, using participants without CVD at age 70 as the reference: 1.56, 95% confidence interal [CI] 1.18-2.08) but not after 60 years. In participants with CVD, a greater number of lifestyle factors at recommended levels post-CVD was associated with a lower dementia risk (per lifestyle factor at recommended level HR: 0.73, 95% CI 0.59-0.92).

DISCUSSION

Our results suggest that early onset CVD is associated with a higher dementia risk at older ages. In those with CVD, the dementia risk was lower if lifestyle factors are at recommended levels following CVD diagnosis.

HIGHLIGHTS

CVD in midlife but not in late life is associated with a higher risk of dementia. Dementia risk in CVD patients is lower if their lifestyle factors are at recommended levels. These findings provide evidence to promote CVD prevention in midlife or earlier. Study findings also show the importance of a healthy lifestyle in those with CVD.

Novel Blood-Based Biomarkers and Disease Modifying Therapies for Alzheimer's Disease. Are We Ready for the New Era?

Recent positive trials for novel disease modifying therapies of anti-amyloid monoclonal antibodies represent a paradigm shift in the prevention and management of Alzheimer's disease, a relentlessly progressive and debilitating disease of old age. The reported efficacy of these new agents when given early in the disease trajectory is dependent on an early and accurate disease diagnosis, which is currently based on cerebrospinal fluid tests or/and neuro-imaging studies such as positron emission tomography. These confirmatory tests provide in vivo evidence of the pathological signature of Alzheimer's disease, of increased cerebral amyloid and tau burden and neurodegeneration. The emergence of blood-based biomarkers represents another breakthrough, offering a less invasive and scalable diagnostic tool that could be applied in both primary and specialist care settings, potentially revolutionizing Alzheimer's disease clinical pathways. However, healthcare systems face challenges in the adoption of these new technologies and therapies due to diagnostic and treatment capacity constraints, as well as financial and infrastructure requirements.

Change in lipids before onset of dementia, coronary heart disease, and mortality: A 28-year follow-up Whitehall II prospective cohort study

INTRODUCTION

The association of lipids with dementia remains a subject of debate. Using data from 7,672 participants of the Whitehall II prospective cohort study, we examined whether timing of exposure, length of follow-up, or sex modifies this association.

METHODS

Twelve markers of lipid levels were measured from fasting blood and eight among them a further five times. We performed time-to-event as well as trajectory analyses.

RESULTS

No associations were observed in men; in women most lipids were associated with the risk of dementia, but only for events occurring after the first 20 years of follow-up. Differences in lipid trajectories in men emerged only in the years immediately before diagnosis whereas in women total cholesterol (TC), LDL-cholesterol (LDL-C), non-HDL-cholesterol (non-HDL-C), TC/HDL-C, and LDL-C/HDL-C were higher in midlife among dementia cases before declining progressively.

DISCUSSION

Abnormal lipid levels in midlife seem to be associated with a higher risk of dementia in women.

Is metabolic-healthy obesity associated with risk of dementia? An age-stratified analysis of the Whitehall II cohort study

BACKGROUND

Metabolically healthy obesity is hypothesized to be a benign condition but whether this is the case for dementia remains debated. We examined the role of age at assessment of metabolic-obesity phenotypes in associations with incident dementia.

METHODS

Obesity (body mass index ≥ 30 kg/m2) and poor metabolic health (≥ 2 of elevated serum triglycerides, low HDL-C, elevated blood pressure, and elevated serum fasting glucose) were used to define four metabolic-obesity phenotypes (metabolically healthy (MHNO) and unhealthy non-obesity (MUNO), metabolically healthy (MHO) and unhealthy obesity (MUO)) at < 60, 60 to < 70, and ≥ 70 years using 6 waves of data from the Whitehall II study and their associations with incident dementia was examined using Cox regression.

RESULTS

Analyses with exposures measured < 60, 60 to < 70, and ≥ 70 years involved 410 (5.8%), 379 (5.6%), and 262 (7.4%) incident dementia cases over a median follow-up of 20.8, 10.3, and 4.2 years respectively. In analyses of individual components, obesity before 60 years (HR 1.41, 95% CI: [1.08, 1.85]) but not at older ages was associated with dementia; unhealthy metabolic status when present < 60 years (HR 1.33, 95% CI: [1.08, 1.62]) and 60 to < 70 years (HR 1.32, 95% CI: [1.07, 1.62]) was associated with dementia. Compared to the metabolically healthy non-obesity group, the risk of dementia was higher in those with metabolically healthy obesity before 60 years (1.69; 95% CI: [1.16, 2.45]); this was not the case when metabolic-obesity phenotype was present at 60 to < 70 years or ≥ 70 years. Analyses at older ages were on smaller numbers due to death and drop-out but inverse probability weighting to account for missing data yielded similar results.

CONCLUSIONS

Individuals with metabolically healthy obesity before age 60 had a higher risk of incident dementia over a 27-year follow-up; the excess risk dissipates when metabolic health and obesity are measured after 70 years.

Age at menopause and all-cause and cause-specific dementia: a prospective analysis of the UK Biobank cohort

STUDY QUESTION

Are there associations between natural or surgical menopause and incident dementia by age at menopause?

SUMMARY ANSWER

Compared to age at menopause of 46-50 years, earlier natural menopause (≤40 and 41-45 years) was related to higher risk of all-cause dementia, while a U-shape relationship was observed between age at surgical menopause and risk of dementia.

WHAT IS KNOWN ALREADY

Menopause marks the end of female reproductive period. Age at menopause reflects the length of exposure to endogenous estrogen. Evidence on the association between age at natural, surgical menopause, and risk of dementia has been inconsistent.

STUDY DESIGN, SIZE, DURATION

A population-based cohort study involving 160 080 women who participated in the UK Biobank study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with no dementia at baseline, and had no missing data on key exposure variables and covariates were included. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs on the association of categorical menopause age with incident all-cause dementia, Alzheimer's disease (AD) and vascular dementia (VD). Restricted cubic splines were used to model the non-linear relationship between continuous age at natural, surgical menopause, and risk of dementia. In addition, we analyzed the interaction effect of ever-used menopausal hormone therapy (MHT) at baseline, income level, leisure activities, and age at menopause on risk of dementia.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to women with age at menopause of 46-50 years, women with earlier natural menopause younger than 40 years (1.36, 1.01-1.83) and 41-45 years (1.19, 1.03-1.39) had a higher risk of all-cause dementia, while late natural menopause >55 years was linked to lower risk of dementia (0.83, 0.71-0.98). Compared to natural menopause, surgical menopause was associated with 10% higher risk of dementia (1.10, 0.98-1.24). A U-shape relationship was observed between surgical menopause and risk of dementia. Women with surgical menopause before age 40 years (1.94, 1.38-2.73) and after age 55 years (1.65, 1.21-2.24) were both linked to increased risk of all-cause dementia. Women with early natural menopause without ever taking MHT at baseline had an increased risk of AD. Also, in each categorized age at the menopause level, higher income level or higher number of leisure activities was linked to a lowers risk of dementia.

LIMITATIONS, REASONS FOR CAUTION

Menopausal age was based on women's self-report, which might cause recall bias.

WIDER IMPLICATION OF THE FINDINGS

Women who experienced natural menopause or had surgical menopause at an earlier age need close monitoring and engagement for preventive health measures to delay the development of dementia.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the Start-up Foundation for Scientific Research in Shandong University (202099000066), Science Fund Program for Excellent Young Scholars of Shandong Provence (Overseas) (2022HWYQ-030), and the National Natural Science Foundation of China (82273702). There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Survival and critical care use among people with dementia in a large English cohort

BACKGROUND

Admitting people with dementia to critical care units may not always lead to a clear survival benefit. Critical care admissions of people with dementia vary across countries. Little is known about the use and trends of critical care admissions of people with dementia in England.

OBJECTIVE

To investigate critical care use and survival among people with dementia in a large London catchment area.

METHODS

A retrospective cohort study using data from dementia assessment services in south London, UK (2007-20) linked with national hospitalisation data to ascertain critical care admissions. Outcomes included age-sex-standardised critical care use and 1-year post-critical care admission survival by dementia severity (binary: mild versus moderate/severe). We used logistic regression and Kaplan-Meier survival plots for investigating 1-year survival following a critical care admission and linear regressions for time trends.

RESULTS

Of 19,787 people diagnosed with dementia, 726 (3.7%) had ≥1 critical care admission at any time after receiving their dementia diagnosis. The overall 1-year survival of people with dementia, who had a CCA, was 47.5% (n = 345). Dementia severity was not associated with 1-year survival following a critical care admission (mild dementia versus moderate-severe dementia odds of 1-year mortality OR: 0.90, 95% CI [0.66-1.22]). Over the 12-year period from 2008 to 2019, overall critical care use decreased (β = -0.05; 95% CI = -0.01, -0.0003; P = 0.03), while critical care admissions occurring during the last year of life increased (β = 0.11, 95% CI = 0.01, 0.20, P = 0.03).

CONCLUSIONS

In this cohort, while critical care use among people with dementia declined overall, its use increased among those in their last year of life. Survival remains comparable to that observed in general older populations.

Associations between air pollution and mental health service use in dementia: a retrospective cohort study

BACKGROUND

Little is known about the role of air pollution in how people with dementia use mental health services.

OBJECTIVE

We examined longitudinal associations between air pollution exposure and mental health service use in people with dementia.

METHODS

In 5024 people aged 65 years or older with dementia in South London, high resolution estimates of nitrogen dioxide (NO2) and particulate matter (PM2.5 and PM10) levels in ambient air were linked to residential addresses. Associations between air pollution and Community Mental Health Team (CMHT) events (recorded over 9 years) were examined using negative binomial regression models. Cognitive function was measured using the Mini Mental State Examination (MMSE) and health and social functioning was measured using the Health of the Nation Outcomes Scale (HoNOS65+). Associations between air pollution and both MMSE and HoNOS65+ scores were assessed using linear regression models.

FINDINGS

In the first year of follow-up, increased exposure to all air pollutants was associated with an increase in the use of CMHTs in a dose-response manner. These associations were strongest when we compared the highest air pollution quartile (quartile 4: Q4) with the lowest quartile (Q1) (eg, NO2: adjusted incidence rate ratio (aIRR) 1.27, 95% CI 1.11 to 1.45, p<0.001). Dose-response patterns between PM2.5 and CMHT events remained at 5 and 9 years. Associations were strongest for patients with vascular dementia. NO2 levels were linked with poor functional status, but not cognitive function.

CONCLUSIONS

Residential air pollution exposure is associated with increased CMHT usage among people with dementia.

CLINICAL IMPLICATIONS

Efforts to reduce pollutant exposures in urban settings might reduce the use of mental health services in people with dementia, freeing up resources in already considerably stretched psychiatric services.

Estimating Dementia Risk Using Multifactorial Prediction Models

Importance

The clinical value of current multifactorial algorithms for individualized assessment of dementia risk remains unclear.

Objective

To evaluate the clinical value associated with 4 widely used dementia risk scores in estimating 10-year dementia risk.

Design, Setting, and Participants

This prospective population-based UK Biobank cohort study assessed 4 dementia risk scores at baseline (2006-2010) and ascertained incident dementia during the following 10 years. Replication with a 20-year follow-up was based on the British Whitehall II study. For both analyses, participants who had no dementia at baseline, had complete data on at least 1 dementia risk score, and were linked to electronic health records from hospitalizations or mortality were included. Data analysis was conducted from July 5, 2022, to April 20, 2023.

Exposures

Four existing dementia risk scores: the Cardiovascular Risk Factors, Aging and Dementia (CAIDE)-Clinical score, the CAIDE-APOE-supplemented score, the Brief Dementia Screening Indicator (BDSI), and the Australian National University Alzheimer Disease Risk Index (ANU-ADRI).

Main Outcomes and Measures

Dementia was ascertained from linked electronic health records. To evaluate how well each score predicted the 10-year risk of dementia, concordance (C) statistics, detection rate, false-positive rate, and the ratio of true to false positives were calculated for each risk score and for a model including age alone.

Results

Of 465 929 UK Biobank participants without dementia at baseline (mean [SD] age, 56.5 [8.1] years; range, 38-73 years; 252 778 [54.3%] female participants), 3421 were diagnosed with dementia at follow-up (7.5 per 10 000 person-years). If the threshold for a positive test result was calibrated to achieve a 5% false-positive rate, all 4 risk scores detected 9% to 16% of incident dementia and therefore missed 84% to 91% (failure rate). The corresponding failure rate was 84% for a model that included age only. For a positive test result calibrated to detect at least half of future incident dementia, the ratio of true to false positives ranged between 1 to 66 (for CAIDE-APOE-supplemented) and 1 to 116 (for ANU-ADRI). For age alone, the ratio was 1 to 43. The C statistic was 0.66 (95% CI, 0.65-0.67) for the CAIDE clinical version, 0.73 (95% CI, 0.72-0.73) for the CAIDE-APOE-supplemented, 0.68 (95% CI, 0.67-0.69) for BDSI, 0.59 (95% CI, 0.58-0.60) for ANU-ADRI, and 0.79 (95% CI, 0.79-0.80) for age alone. Similar C statistics were seen for 20-year dementia risk in the Whitehall II study cohort, which included 4865 participants (mean [SD] age, 54.9 [5.9] years; 1342 [27.6%] female participants). In a subgroup analysis of same-aged participants aged 65 (±1) years, discriminatory capacity of risk scores was low (C statistics between 0.52 and 0.60).

Conclusions and Relevance

In these cohort studies, individualized assessments of dementia risk using existing risk prediction scores had high error rates. These findings suggest that the scores were of limited value in targeting people for dementia prevention. Further research is needed to develop more accurate algorithms for estimation of dementia risk.

Association between hearing aid use and all-cause and cause-specific dementia: an analysis of the UK Biobank cohort

BACKGROUND

Dementia and hearing loss are both highly prevalent conditions among older adults. We aimed to examine the association between hearing aid use and risk of all-cause and cause-specific dementia among middle-aged and older-aged adults, and to explore the roles of mediators and moderators in their association.

METHODS

We used data from the UK Biobank, a population-based cohort study, which recruited adults aged 40-69 years between 2006 and 2010 across 22 centres in England, Scotland, and Wales. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs between self-reported hearing aid use status (hearing loss with or without hearing aids) at baseline and risk of dementia (all-cause dementia, Alzheimer's disease, vascular dementia, and non-Alzheimer's disease non-vascular dementia). Dementia diagnoses were ascertained using hospital records and death-register data. We also analysed the roles of mediators (self-reported social isolation, loneliness, and mood) and moderators (self-reported education and income, smoking, morbidity, and measured APOE allele status).

FINDINGS

After the exclusion of people who did not answer the question on hearing difficulties (n=25 081 [5·0%]) and those with dementia at baseline visit (n=283 [0·1%]), we included 437 704 people in the analyses. Compared with participants without hearing loss, people with hearing loss without hearing aids had an increased risk of all-cause dementia (HR 1·42 [95% CI 1·29-1·56]); we found no increased risk in people with hearing loss with hearing aids (1·04 [0·98-1·10]). The positive association of hearing aid use was observed in all-cause dementia and cause-specific dementia subtypes (Alzheimer's disease, vascular dementia, and non-Alzheimer's disease non-vascular dementia). The attributable risk proportion of dementia for hearing loss was estimated to be 29·6%. Of the total association between hearing aid use and all-cause dementia, 1·5% was mediated by reducing social isolation, 2·3% by reducing loneliness, and 7·1% by reducing depressed mood.

INTERPRETATION

In people with hearing loss, hearing aid use is associated with a risk of dementia of a similar level to that of people without hearing loss. With the postulation that up to 8% of dementia cases could be prevented with proper hearing loss management, our findings highlight the urgent need to take measures to address hearing loss to improve cognitive decline.

FUNDING

National Natural Science Foundation of China and Shandong Province, Taishan Scholars Project, China Medical Board, and China Postdoctoral Science Foundation.

Cataract, Cataract Surgery, and Risk of Incident Dementia: A Prospective Cohort Study of 300,823 Participants

BACKGROUND

Visual impairment and interventions to preserve vision may impact dementia risk. Thus, we aimed to explore the associations of cataract and cataract surgery with the risk of dementia.

METHODS

Prospective data from 300,823 individuals in the UK Biobank were used. We used multivariate Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals for associations, with healthy control subjects as a reference. The same method was used to explore the effects of surgery on dementia outcomes of patients with cataract. One-way analysis of variance was performed to examine the associations between cataract and brain morphometric measures.

RESULTS

After a mean follow-up of 8.4 years, 3226 individuals were diagnosed with dementia. The nonsurgical cataract group had increased risk of all-cause dementia (HR, 1.214; 95% CI, 1.012-1.456; p = .037) and Alzheimer's disease (HR, 1.479; 95% CI, 1.105-1.981; p = .009). However, there was no difference in dementia risk between the cataract surgery group and the healthy control group. Cataract surgery was associated with decreased risk of all-cause dementia (HR, 0.632; 95% CI, 0.421-0.947; p = .026) and Alzheimer's disease (HR, 0.399; 95% CI, 0.196-0.812; p = .011) compared with the nonsurgical group. Additionally, cataract was negatively associated with cortical volumes, aging-related subcortical volumes, and fractional anisotropy of white matter fibers.

CONCLUSIONS

Cataract patients who did not receive surgical treatment had an increased risk of dementia. However, cataract surgery could reverse the risk of dementia. Our findings on brain structures and pathways in patients with cataract also provided evidence for the mechanism. Reversible visual impairment, such as cataract, is a promising modifiable risk factor for dementia.

Association Between Regular Laxative Use and Incident Dementia in UK Biobank Participants

BACKGROUND AND OBJECTIVES

The use of over-the-counter laxatives is common in the general population. The microbiome-gut-brain axis hypothesis suggests that the use of laxatives could be associated with dementia. We aimed to examine the association between the regular use of laxatives and the incidence of dementia in UK Biobank participants.

METHODS

This prospective cohort study was based on UK Biobank participants aged 40-69 years without a history of dementia. Regular use of laxatives was defined as self-reported use in most days of the week for the last 4 weeks at baseline (2006-2010). The outcomes were all-cause dementia, Alzheimer disease (AD), and vascular dementia (VD), identified from linked hospital admissions or death registers (up to 2019). Sociodemographic characteristics, lifestyle factors, medical conditions, family history, and regular medication use were adjusted for in the multivariable Cox regression analyses.

RESULTS

Among the 502,229 participants with a mean age of 56.5 (SD 8.1) years at baseline, 273,251 (54.4%) were female, and 18,235 (3.6%) reported regular use of laxatives. Over a mean follow-up of 9.8 years, 218 (1.3%) participants with regular use of laxatives and 1,969 (0.4%) with no regular use developed all-cause dementia. Multivariable analyses showed that regular use of laxatives was associated with increased risk of all-cause dementia (hazard ratio [HR] 1.51; 95% CI 1.30-1.75) and VD (HR 1.65; 95% CI 1.21-2.27), with no significant association observed for AD (HR 1.05; 95% CI 0.79-1.40). The risk of both all-cause dementia and VD increased with the number of regularly used laxative types (p trend 0.001 and 0.04, respectively). Among the participants who clearly reported that they were using just 1 type of laxative (n = 5,800), only those using osmotic laxatives showed a statistically significantly higher risk of all-cause dementia (HR 1.64; 95% CI 1.20-2.24) and VD (HR 1.97; 95% CI 1.04-3.75). These results remained robust in various subgroup and sensitivity analyses.

DISCUSSION

Regular use of laxatives was associated with a higher risk of all-cause dementia, particularly in those who used multiple laxative types or osmotic laxative.

The associations of socioeconomic status with incident dementia and Alzheimer's disease are modified by leucocyte telomere length: a population-based cohort study

Socio-economic status (SES) and biological aging are risk factors for dementia, including Alzheimer's disease, however, it is less clear if the associations with SES vary sufficiently across different biological age strata. We used data from 331,066 UK Biobank participants aged 38-73 with mean follow-up of 12 years to examine if associations between SES (assessed by educational attainment, employment status and household income) and dementia and Alzheimer's disease are modified by biological age (assessed by leucocyte telomere length: LTL). Diagnosis of events was ascertained through hospital admissions data. Cox regressions were used to estimate hazard ratios [HRs]. A consistent dose-response relationship was found, with participants in low SES and shorter LTL strata (double-exposed group) reporting 3.28 (95% confidence interval [CI] 2.57-4.20) and 3.44 (95% CI 2.35-5.04) times higher risks of incident dementia and Alzheimer's disease respectively, compared to those of high SES and longer LTL (least-exposed group). Of interest is a synergistic interaction between SES and LTL to increase risk of dementia (RERI 0.57, 95% CI 0.07-1.06) and Alzheimer's disease (RERI 0.79, 95% CI 0.02-1.56). Our findings that SES and biological age (LTL) are synergistic risk factors of dementia and Alzheimer's disease may suggest the need to target interventions among vulnerable sub-groups.

Mediterranean diet adherence is associated with lower dementia risk, independent of genetic predisposition: findings from the UK Biobank prospective cohort study

BACKGROUND

The identification of effective dementia prevention strategies is a major public health priority, due to the enormous and growing societal cost of this condition. Consumption of a Mediterranean diet (MedDiet) has been proposed to reduce dementia risk. However, current evidence is inconclusive and is typically derived from small cohorts with limited dementia cases. Additionally, few studies have explored the interaction between diet and genetic risk of dementia.

METHODS

We used Cox proportional hazard regression models to explore the associations between MedDiet adherence, defined using two different scores (Mediterranean Diet Adherence Screener [MEDAS] continuous and Mediterranean diet Pyramid [PYRAMID] scores), and incident all-cause dementia risk in 60,298 participants from UK Biobank, followed for an average 9.1 years. The interaction between diet and polygenic risk for dementia was also tested.

RESULTS

Higher MedDiet adherence was associated with lower dementia risk (MEDAS continuous: HR = 0.77, 95% CI = 0.65-0.91; PYRAMID: HR = 0.86, 95% CI = 0.73-1.02 for highest versus lowest tertiles). There was no significant interaction between MedDiet adherence defined by the MEDAS continuous and PYRAMID scores and polygenic risk for dementia.

CONCLUSIONS

Higher adherence to a MedDiet was associated with lower dementia risk, independent of genetic risk, underlining the importance of diet in dementia prevention interventions.

Recording of intellectual disability in general hospitals in England 2006-2019: Cohort study using linked datasets

BACKGROUND

Accurate recognition and recording of intellectual disability in those who are admitted to general hospitals is necessary for making reasonable adjustments, ensuring equitable access, and monitoring quality of care. In this study, we determined the rate of recording of intellectual disability in those with the condition who were admitted to hospital and factors associated with the condition being unrecorded.

METHODS AND FINDINGS

Retrospective cohort study using 2 linked datasets of routinely collected clinical data in England. We identified adults with diagnosed intellectual disability in a large secondary mental healthcare database and used general hospital records to investigate recording of intellectual disability when people were admitted to general hospitals between 2006 and 2019. Trends over time and factors associated with intellectual disability being unrecorded were investigated. We obtained data on 2,477 adults with intellectual disability who were admitted to a general hospital in England at least once during the study period (total number of admissions = 27,314; median number of admissions = 5). People with intellectual disability were accurately recorded as having the condition during 2.9% (95% CI 2.7% to 3.1%) of their admissions. Broadening the criteria to include a nonspecific code of learning difficulty increased recording to 27.7% (95% CI 27.2% to 28.3%) of all admissions. In analyses adjusted for age, sex, ethnicity, and socioeconomic deprivation, having a mild intellectual disability and being married were associated with increased odds of the intellectual disability being unrecorded in hospital records. We had no measure of quality of hospital care received and could not relate this to the presence or absence of a record of intellectual disability in the patient record.

CONCLUSIONS

Recognition and recording of intellectual disability in adults admitted to English general hospitals needs to be improved. Staff awareness training, screening at the point of admission, and data sharing between health and social care services could improve care for people with intellectual disability.

Changes over time in the Chronic Liver Disease risk score predict liver-related outcomes: longitudinal analysis of the Whitehall II study

BACKGROUND AND AIMS

The Chronic Liver Disease (CLivD) risk score was recently shown to predict future advanced liver disease in the general population. We here investigated the impact of individual CLivD-score changes over time.

METHODS

Participants of both phase 3 (baseline, 1991-1994) and phase 5 (follow-up, 1997-1999) examinations of the Whitehall II study were followed for liver-related outcomes (hospitalization, cancer, death) until December 2019 through linkage with electronic healthcare registers. The CLivD score, its modifiable components (alcohol use, waist-hip ratio [WHR], diabetes, and smoking), and their individual changes were studied.

RESULTS

Among 6590 adults (mean age 50 years, 30% women) with a median 21-year follow-up, there were 80 liver outcomes. A rise in the CLivD score between baseline and follow-up examinations significantly increased the risk for liver-related outcomes (adjusted hazard ratio [aHR] 1.62, 95% confidence interval [CI] 1.01-2.60), more so in subjects with baseline intermediate-high CLivD scores (HR 2.4 for a CLivD-change) compared to minimal-low CLivD scores. Adverse changes over time in alcohol use and WHR, and new-onset diabetes also predicted liver outcomes. In contrast to WHR, changes in body weight (kg) showed a U-shaped association with liver outcomes.

CONCLUSIONS

A change in the CLivD score over time corresponds to a true change in the risk for liver-related outcomes, suggesting the usefulness of the CLivD score for assessing response to liver-directed lifestyle interventions. Changes in WHR predicted liver outcomes better than changes in body weight or waist circumference, independent of body mass index, supporting the WHR in assessing risk for future liver disease.

Leading mediators of sex differences in the incidence of dementia in community-dwelling adults in the UK Biobank: a retrospective cohort study

BACKGROUND

Little is known regarding whether sex assigned at birth modifies the association between several predictive factors for dementia and the risk of dementia itself.

METHODS

Our retrospective cohort study included 214,670 men and 214,670 women matched by age at baseline from the UK Biobank. Baseline data were collected between 2006 and 2010, and incident dementia was ascertained using hospital inpatient or death records until January 2021. Mediation analysis was tested for 133 individual factors.

RESULTS

Over 5,117,381 person-years of follow-up, 5928 cases of incident all-cause dementia (452 cases of young-onset dementia, 5476 cases of late-onset dementia) were documented. Hazard ratios (95% CI) for all-cause, young-onset, and late-onset dementias associated with the male sex (female as reference) were 1.23 (1.17-1.29), 1.42 (1.18-1.71), and 1.21 (1.15-1.28), respectively. Out of 133 individual factors, the strongest mediators for the association between sex and incident dementia were multimorbidity risk score (percentage explained (95% CI): 62.1% (45.2-76.6%)), apolipoprotein A in the blood (25.5% (15.2-39.4%)), creatinine in urine (24.9% (16.1-36.5%)), low-density lipoprotein cholesterol in the blood (23.2% (16.2-32.1%)), and blood lymphocyte percentage (21.1% (14.5-29.5%)). Health-related conditions (percentage (95% CI) explained: 74.4% (51.3-88.9%)) and biomarkers (83.0% (37.5-97.5%)), but not lifestyle factors combined (30.1% (20.7-41.6%)), fully mediated sex differences in incident dementia. Health-related conditions combined were a stronger mediator for late-onset (75.4% (48.6-90.8%)) than for young-onset dementia (52.3% (25.8-77.6%)), whilst lifestyle factors combined were a stronger mediator for young-onset (42.3% (19.4-69.0%)) than for late-onset dementia (26.7% (17.1-39.2%)).

CONCLUSIONS

Our analysis matched by age has demonstrated that men had a higher risk of all-cause, young-onset, and late-onset dementias than women. This association was fully mediated by health-related conditions or blood/urinary biomarkers and largely mediated by lifestyle factors. Our findings are important for understanding potential mechanisms of sex in dementia risk.

Severity of Dementia and Survival in Patients Diagnosed with Colorectal Cancer: A National Cohort Study in England and Wales

AIMS

There is little evidence about the survival of patients with colorectal cancer (CRC) also diagnosed with dementia. We quantified dementia severity and estimated how it is associated with 2-year overall survival.

MATERIALS AND METHODS

Records of patients aged 65 years or older diagnosed with CRC in England and Wales were identified. A novel proxy for dementia severity combined dementia diagnosis in administrative hospital data with Eastern Cooperative Oncology Group performance status. Cox regression was used to estimate hazard ratios with and without risk adjustment.

RESULTS

In total, 4033 of 105 250 CRC patients (3.8%) had dementia recorded. Two-year survival decreased with increasing dementia severity from 65.4% without dementia, 53.5% with mild dementia, 33.0% with moderate dementia to 16.5% with severe dementia (hazard ratio comparing severe with no dementia: 2.97; 95% confidence interval 2.79, 3.16). Risk adjustment for comorbidity and cancer stage reduced this association slightly (hazard ratio 2.52; 95% confidence interval 2.37, 2.68) and additional adjustment for treatment factors reduced it further (hazard ratio 1.60; 95% confidence interval 1.50, 1.70).

CONCLUSIONS

Survival of CRC patients varied strongly according to dementia severity, suggesting that a 'one-size-fits-all' policy for the care of CRC patients with dementia is not appropriate. Comprehensive assessment of cancer patients with dementia that considers dementia severity is essential in a shared decision-making process that ensures patients receive the most appropriate treatment for their individual needs and preferences.

Retrospective study of more than 5 million emergency admissions to hospitals in England: Epidemiology and outcomes for people with dementia

INTRODUCTION

People living with dementia (PwD) admitted in emergency to an acute hospital may be at higher risk of inappropriate care and poorer outcomes including longer hospitalisations and higher risk of emergency re-admission or death. Since 2009 numerous national and local initiatives in England have sought to improve hospital care for PwD. We compared outcomes of emergency admissions for cohorts of patients aged 65+ with and without dementia at three points in time.

METHODS

We analysed emergency admissions (EAs) from the Hospital Episodes Statistics datasets for England 2010/11, 2012/13 and 2016/17. Dementia upon admission was based on a diagnosis in the patient's hospital records within the last five years. Outcomes were length of hospital stays (LoS), long stays (> = 15 days), emergency re-admissions (ERAs) and death in hospital or within 30 days post-discharge. A wide range of covariates were taken into account, including patient demographics, pre-existing health and reasons for admission. Hierarchical multivariable regression analysis, applied separately for males and females, estimated group differences adjusted for covariates.

RESULTS

We included 178 acute hospitals and 5,580,106 EAs, of which 356,992 (13.9%) were male PwD and 561,349 (18.6%) female PwD. Uncontrolled differences in outcomes between the patient groups were substantial but were considerably reduced after control for covariates. Covariate-adjusted differences in LoS were similar at all time-points and in 2016/17 were 17% (95%CI 15%-18%) and 12% (10%-14%) longer for male and female PwD respectively compared to patients without dementia. Adjusted excess risk of an ERA for PwD reduced over time to 17% (15%-18%) for males and 17% (16%-19%) for females, but principally due to increased ERA rates amongst patients without dementia. Adjusted overall mortality was 30% to 40% higher for PwD of both sexes throughout the time-period; however, adjusted in-hospital rates of mortality differed only slightly between the patient groups, whereas PwD had around double the risk of dying within 30 days of being discharged.

CONCLUSION

Over the six-year period, covariate-adjusted hospital LoS, ERA rates and in-hospital mortality rates for PwD were only slightly elevated compared to similar patients without dementia and remaining differences potentially reflect uncontrolled confounding. PwD however, were around twice as likely to die shortly after discharge, the reasons for which require further investigation. Despite being widely used for service evaluation, LoS, ERA and mortality may lack sensitivity to changes in hospital care and support to PwD.

Contribution of smoking towards the association between socioeconomic position and dementia: 32-year follow-up of the Whitehall II prospective cohort study

Background

There is consistent evidence of social inequalities in dementia but the mechanisms underlying this association remain unclear. We examined the role of smoking in midlife in socioeconomic differences in dementia at older ages.

Methods

Analyses were based on 9951 (67% men) participants, median age 44.3 [IQR=39.6, 50.3] years at baseline in 1985-1988, from the Whitehall II cohort study. Socioeconomic position (SEP) and smoking (smoking status (current, ex-, never-smoker), pack years of smoking, and smoking history score (combining status and pack-years)) were measured at baseline. Counterfactual mediation analysis was used to examine the contribution of smoking to the association between SEP and dementia.

Findings

During a median follow-up of 31.6 (IQR 31.1, 32.6) years, 628 participants were diagnosed with dementia and 2110 died. Analyses adjusted for age, sex, ethnicity, education, and SEP showed smokers (hazard ratio [HR] 1.36 [95% CI 1.10-1.68]) but not ex-smokers (HR 0.95 [95% CI 0.79-1.14]) to have a higher risk of dementia compared to never-smokers; similar results for smoking were obtained for pack-years of smoking and smoking history score. Mediation analysis showed low SEP to be associated with higher risk of dementia (HRs between 1.97 and 2.02, depending on the measure of smoking in the model); estimate for the mediation effect was 16% for smoking status (Indirect Effect HR 1.09 [95% CI 1.03-1.15]), 7% for pack-years of smoking (Indirect Effect HR 1.03 [95% CI 1.01-1.06]) and 11% for smoking history score (Indirect Effect HR 1.06 [95% CI 1.02-1.10]).

Interpretation

Our findings suggest that part of the social inequalities in dementia is mediated by smoking.

Funding

NIH.

How good are medical and death records for identifying dementia?

INTRODUCTION

Retrospective studies using administrative data may be an efficient way to assess risk factors for dementia if diagnostic accuracy is known.

METHODS

Within-individual clinical diagnoses of Alzheimer's disease (AD) and all-cause dementia in ambulatory (outpatient) surgery, inpatient, Medicare administrative records and death certificates were compared with research diagnoses among participants of Cache County Study on Memory, Health, and Aging (CCSMHA) (1995-2008, N = 5092).

RESULTS

Combining all sources of clinical health data increased sensitivity for identifying all-cause dementia (71%) and AD (48%), while maintaining relatively high specificity (81% and 93%, respectively). Medicare claims had the highest sensitivity for case identification (57% and 40%, respectively).

DISCUSSION

Administrative health data may provide a less accurate method than a research evaluation for identifying individuals with dementing disease, but accuracy is improved by combining health data sources. Assessing all-cause dementia versus a specific cause of dementia such as AD will result in increased sensitivity, but at a cost to specificity.

Association of sleep duration at age 50, 60, and 70 years with risk of multimorbidity in the UK: 25-year follow-up of the Whitehall II cohort study

BACKGROUND

Sleep duration has been shown to be associated with individual chronic diseases but its association with multimorbidity, common in older adults, remains poorly understood. We examined whether sleep duration is associated with incidence of a first chronic disease, subsequent multimorbidity and mortality using data spanning 25 years.

METHODS AND FINDINGS

Data were drawn from the prospective Whitehall II cohort study, established in 1985 on 10,308 persons employed in the London offices of the British civil service. Self-reported sleep duration was measured 6 times between 1985 and 2016, and data on sleep duration was extracted at age 50 (mean age (standard deviation) = 50.6 (2.6)), 60 (60.3 (2.2)), and 70 (69.2 (1.9)). Incidence of multimorbidity was defined as having 2 or more of 13 chronic diseases, follow-up up to March 2019. Cox regression, separate analyses at each age, was used to examine associations of sleep duration at age 50, 60, and 70 with incident multimorbidity. Multistate models were used to examine the association of sleep duration at age 50 with onset of a first chronic disease, progression to incident multimorbidity, and death. Analyses were adjusted for sociodemographic, behavioral, and health-related factors. A total of 7,864 (32.5% women) participants free of multimorbidity had data on sleep duration at age 50; 544 (6.9%) reported sleeping ≤5 hours, 2,562 (32.6%) 6 hours, 3,589 (45.6%) 7 hours, 1,092 (13.9%) 8 hours, and 77 (1.0%) ≥9 hours. Compared to 7-hour sleep, sleep duration ≤5 hours was associated with higher multimorbidity risk (hazard ratio: 1.30, 95% confidence interval = 1.12 to 1.50; p < 0.001). This was also the case for short sleep duration at age 60 (1.32, 1.13 to 1.55; p < 0.001) and 70 (1.40, 1.16 to 1.68; p < 0.001). Sleep duration ≥9 hours at age 60 (1.54, 1.15 to 2.06; p = 0.003) and 70 (1.51, 1.10 to 2.08; p = 0.01) but not 50 (1.39, 0.98 to 1.96; p = 0.07) was associated with incident multimorbidity. Among 7,217 participants free of chronic disease at age 50 (mean follow-up = 25.2 years), 4,446 developed a first chronic disease, 2,297 progressed to multimorbidity, and 787 subsequently died. Compared to 7-hour sleep, sleeping ≤5 hours at age 50 was associated with an increased risk of a first chronic disease (1.20, 1.06 to 1.35; p = 0.003) and, among those who developed a first disease, with subsequent multimorbidity (1.21, 1.03 to 1.42; p = 0.02). Sleep duration ≥9 hours was not associated with these transitions. No association was found between sleep duration and mortality among those with existing chronic diseases. The study limitations include the small number of cases in the long sleep category, not allowing conclusions to be drawn for this category, the self-reported nature of sleep data, the potential for reverse causality that could arise from undiagnosed conditions at sleep measures, and the small proportion of non-white participants, limiting generalization of findings.

CONCLUSIONS

In this study, we observed short sleep duration to be associated with risk of chronic disease and subsequent multimorbidity but not with progression to death. There was no robust evidence of an increased risk of chronic disease among those with long sleep duration at age 50. Our findings suggest an association between short sleep duration and multimorbidity.

Immune system-wide Mendelian randomization and triangulation analyses support autoimmunity as a modifiable component in dementia-causing diseases

Immune system and blood-brain barrier dysfunction are implicated in the development of Alzheimer's and other dementia-causing diseases, but their causal role remains unknown. We performed Mendelian randomization for 1,827 immune system- and blood-brain barrier-related biomarkers and identified 127 potential causal risk factors for dementia-causing diseases. Pathway analyses linked these biomarkers to amyloid-β, tau and α-synuclein pathways and to autoimmunity-related processes. A phenome-wide analysis using Mendelian randomization-based polygenic risk score in the FinnGen study (n = 339,233) for the biomarkers indicated shared genetic background for dementias and autoimmune diseases. This association was further supported by human leukocyte antigen analyses. In inverse-probability-weighted analyses that simulate randomized controlled drug trials in observational data, anti-inflammatory methotrexate treatment reduced the incidence of Alzheimer's disease in high-risk individuals (hazard ratio compared with no treatment, 0.64, 95% confidence interval 0.49-0.88, P = 0.005). These converging results from different lines of human research suggest that autoimmunity is a modifiable component in dementia-causing diseases.

Circulating serum metabolites as predictors of dementia: a machine learning approach in a 21-year follow-up of the Whitehall II cohort study

BACKGROUND

Age is the strongest risk factor for dementia and there is considerable interest in identifying scalable, blood-based biomarkers in predicting dementia. We examined the role of midlife serum metabolites using a machine learning approach and determined whether the selected metabolites improved prediction accuracy beyond the effect of age.

METHODS

Five thousand three hundred seventy-four participants from the Whitehall II study, mean age 55.8 (standard deviation (SD) 6.0) years in 1997-1999 when 233 metabolites were quantified using nuclear magnetic resonance metabolomics. Participants were followed for a median 21.0 (IQR 20.4, 21.7) years for clinically-diagnosed dementia (N=329). Elastic net penalized Cox regression with 100 repetitions of nested cross-validation was used to select models that improved prediction accuracy for incident dementia compared to an age-only model. Risk scores reflecting the frequency with which predictors appeared in the selected models were constructed, and their predictive accuracy was examined using Royston's R², Akaike's information criterion, sensitivity, specificity, C-statistic and calibration.

RESULTS

Sixteen of the 100 models had a better c-statistic compared to an age-only model and 15 metabolites were selected at least once in all 16 models with glucose present in all models. Five risk scores, reflecting the frequency of selection of metabolites, and a 1-SD increment in all five risk scores was associated with higher dementia risk (HR between 3.13 and 3.26). Three of these, constituted of 4, 5 and 15 metabolites, had better prediction accuracy (c-statistic from 0.788 to 0.796) compared to an age-only model (c-statistic 0.780), all p<0.05.

CONCLUSIONS

Although there was robust evidence for the role of glucose in dementia, metabolites measured in midlife made only a modest contribution to dementia prediction once age was taken into account.

Association of Metabolic Syndrome With Incident Dementia: Role of Number and Age at Measurement of Components in a 28-Year Follow-up of the Whitehall II Cohort Study

OBJECTIVE

Previous research suggests an inconsistent association between Metabolic syndrome (MetS) and incident dementia. We examined the role of number of MetS components and age at their assessment for incident dementia.

RESEARCH DESIGN AND METHODS

MetS components (fasting glucose, triglycerides, waist circumference, blood pressure, and HDL cholesterol) on 7,265, 6,660, and 3,608 participants at <60, 60 to <70, and ≥70 years of age were used to examine associations with incident dementia using cause-specific Cox regression.

RESULTS

Analyses of MetS measured at <60, 60 to <70, and ≥70 years involved 393 (5.4%), 497 (7.5%), and 284 (7.9%) dementia cases over a median follow-up of 20.8, 10.4, and 4.2 years, respectively. Every additional MetS component before 60 (hazard ratio [HR] 1.13 [95% CI 1.05, 1.23]) and 60 to <70 (HR 1.08 [95% CI 1.00, 1.16]) but not ≥70 years (HR 1.04 [95% CI 0.96, 1.13]) was associated with higher dementia risk. MetS defined conventionally (≥3 components) before 60 years (HR 1.23 [95% CI 0.96, 1.57]), between 60 and 70 years (HR 1.14 [95% CI 0.91, 1.42]), or >70 years of age (HR 1.10 [95% CI 0.86, 1.40]) was not associated with incident dementia. Multistate models showed higher risk of dementia in those with ≥1 (HR 1.99 [95% CI 1.08, 3.66]) and ≥2 MetS components (HR 1.69 [95% CI 1.12, 2.56]) before 60 years of age, even when they remained free of cardiovascular disease over the follow-up.

CONCLUSIONS

Risk of incident dementia increases with every additional MetS component present in midlife rather than after accumulation of three components; only part of this risk is mediated by cardiovascular disease.

Development and validation of a model to predict incident chronic liver disease in the general population: The CLivD score

BACKGROUND & AIMS

Current screening strategies for chronic liver disease focus on detection of subclinical advanced liver fibrosis but cannot identify those at high future risk of severe liver disease. Our aim was to develop and validate a risk prediction model for incident chronic liver disease in the general population based on widely available factors.

METHODS

Multivariable Cox regression analyses were used to develop prediction models for liver-related outcomes with and without laboratory measures (Model_lab and Model_non-lab) in 25,760 individuals aged 40-70 years. Their data were sourced from the Finnish population-based health examination surveys FINRISK 1992-2012 and Health 2000 (derivation cohort). The models were externally validated in the Whitehall II (n = 5,058) and Copenhagen City Heart Study (CCHS) (n = 3,049) cohorts.

RESULTS

The absolute rate of incident liver outcomes per 100,000 person-years ranged from 53 to 144. The final prediction model included age, sex, alcohol use (drinks/week), waist-hip ratio, diabetes, and smoking, and Model_lab also included gamma-glutamyltransferase values. Internally validated Wolbers' C-statistics were 0.77 for Model_lab and 0.75 for Model_non-lab, while apparent 15-year AUCs were 0.84 (95% CI 0.75-0.93) and 0.82 (95% CI 0.74-0.91). The models identified a small proportion (<2%) of the population with >10% absolute 15-year risk for liver events. Of all liver events, only 10% occurred in participants in the lowest risk category. In the validation cohorts, 15-year AUCs were 0.78 (Model_lab) and 0.65 (Model_non-lab) in the CCHS cohort, and 0.78 (Model_non-lab) in the Whitehall II cohort.

CONCLUSIONS

Based on widely available risk factors, the Chronic Liver Disease (CLivD) score can be used to predict risk of future advanced liver disease in the general population.

LAY SUMMARY

Liver disease often progresses silently without symptoms and thus the diagnosis is often delayed until severe complications occur and prognosis becomes poor. In order to identify individuals in the general population who have a high risk of developing severe liver disease in the future, we developed and validated a Chronic Liver Disease (CLivD) risk prediction score, based on age, sex, alcohol use, waist-hip ratio, diabetes, and smoking, with or without measurement of the liver enzyme gamma-glutamyltransferase. The CLivD score can be used as part of health counseling, and for planning further liver investigations and follow-up.

Evaluation of routinely collected records for dementia outcomes in UK: a prospective cohort study

OBJECTIVES

To evaluate the characteristics of individuals recorded as having a dementia diagnosis in different routinely collected records and to examine the extent of overlap of dementia coding across data sources. Also, to present comparisons of secondary and primary care records providing value for researchers using routinely collected records for dementia outcome capture.

STUDY DESIGN

A prospective cohort study.

SETTING AND PARTICIPANTS

A cohort of 25 639 men and women in Norfolk, aged 40-79 years at recruitment (1993-1997) followed until 2018 linked to routinely collected to identify dementia cases. Data sources include mortality from death certification and National Health Service (NHS) hospital or secondary care records. Primary care records for a subset of the cohort were also reviewed.

PRIMARY OUTCOME MEASURE

Diagnosis of dementia (any-cause).

RESULTS

Over 2000 participants (n=2635 individuals) were found to have a dementia diagnosis recorded in one or more of the data sources examined. Limited concordance was observed across the secondary care data sources. We also observed discrepancies with primary care records for the subset and report on potential linkage-related selection bias.

CONCLUSIONS

Use of different types of record linkage from varying parts of the UK's health system reveals differences in recorded dementia diagnosis, indicating that dementia can be identified to varying extents in different parts of the NHS system. However, there is considerable variation, and limited overlap in those identified. We present potential selection biases that might occur depending on whether cause of death, or primary and secondary care data sources are used. With the expansion of using routinely collected health data, researchers must be aware of these potential biases and inaccuracies, reporting carefully on the likely extent of limitations and challenges of the data sources they use.

Differing Methodologies Are Required to Estimate Prevalence of Dementia: Single Study Types Are No Longer Reliable

Population-based surveys were used to estimate community prevalence of dementia, but have low response fractions due, among other things, to difficulties in obtaining informed consent from people with diminished capacity. Cohort studies of younger people are subject to recruitment bias and non-random drop-outs. Dementia registries can delineate sub-types of dementia but have limited population coverage and are costly to maintain. Administrative datasets have low costs but may be subject to selection bias and uncertain sensitivity. We propose that astute combination of methodologies, including assessment of coverage and validity of administrative datasets, is the most cost-effective process to estimate and monitor community prevalence.

Effects of aspirin on dementia and cognitive function in diabetic patients: the ASCEND trial

AIMS

Aspirin is widely used in cardiovascular disease prevention but is also associated with an increased risk of bleeding. The net effect of aspirin on dementia and cognitive impairment is uncertain.

METHODS AND RESULTS

In the ASCEND trial, 15 480 people from the UK with diabetes and no history of cardiovascular disease were randomized to aspirin 100 mg daily or matching placebo for a mean of 7.4 years. The 15 427 ASCEND participants with no recorded dementia prior to baseline were included in this cognitive study with a primary pre-specified outcome of 'broad dementia', comprising dementia, cognitive impairment, or confusion. This was ascertained through participant, carer, or general practitioner report or hospital admission diagnosis, by 31 March 2019 (∼2 years beyond the scheduled treatment period). The broad dementia outcome occurred in a similar percentage of participants in the aspirin group and placebo group: 548 participants (7.1%) vs. 598 (7.8%), rate ratio 0.91 [95% confidence interval (CI), 0.81-1.02]. Thus, the CI excluded proportional hazards of >2% and proportional benefits of >19%.

CONCLUSION

Aspirin does not have a large proportional effect on the risk of dementia. Trials or meta-analyses with larger total numbers of incident dementia cases to increase statistical power are needed to assess whether any modest proportional 10-15% benefits of 5-7 years of aspirin use on dementia exist.

CLINICAL TRIAL REGISTRATION

Current Controlled Trials number, ISRCTN60635500; ClinicalTrials.gov number: NCT00135226.

Long-term low-dose acetylsalicylic use shows protective potential for the development of both vascular dementia and Alzheimer's disease in patients with coronary heart disease but not in other individuals from the general population: results from two large cohort studies

BACKGROUND

No population-based cohort study investigated a potential inverse association between long-term low-dose acetylsalicylic acid (ASA) use and all-cause dementia and its two most common sub-types Alzheimer's disease (AD) and vascular dementia (VD) so far.

METHODS

Cox regression models with inverse probability of treatment weighting to model the underlying cardiovascular risk were used to assess the associations of low-dose ASA use with all-cause dementia, AD, and VD incidence in community-dwelling older adults from the German ESTHER study (N = 5258) and the UK Biobank (N = 305,394). Inclusion criteria were age of 55 years or older and completed drug assessment. Meta-analyses of the individual participant data from the two prospective cohort studies were performed.

RESULTS

Four hundred seventy-six cases of all-cause dementia, 157 cases of AD, and 183 cases of VD were diagnosed over a median of 14.3 years of follow-up in ESTHER. In the UK Biobank, 5584 participants were diagnosed with all-cause dementia, 2029 with AD, and 1437 with VD over a median of 11.6 years. The meta-analysis of both cohorts revealed a weak reduction in hazards for all-cause dementia (hazard ratio (HR) [95% confidence interval (CI)]: 0.96 [0.93 to 0.99]). The strongest protective effect of low-dose ASA was observed in participants with coronary heart disease (CHD) in both cohorts, and a significant interaction was detected. In particular, in meta-analysis, a 31% reduction in hazard for AD, 69% for VD and 34% for all-cause dementia were observed (HR [95% CI]: 0.69 [0.59 to 0.80], 0.31 [0.27 to 0.35], 0.46 [0.42 to 0.50], respectively). Furthermore, compared to non-users, users of low-dose ASA for 10 years or longer (who likely use it because they have CHD or a related diagnosis putting them at an increased risk for cardiovascular events) demonstrated a strong protective effect on all dementia outcomes, especially for VD (HR [95% CI]: 0.48 [0.42 to 0.56]) whereas no protective associations were observed with shorter low-dose ASA use.

CONCLUSIONS

The protective potential of low-dose ASA for all-cause dementia, AD, and VD seems to strongly depend on pre-existing CHD and the willingness of patients to take it for a minimum of ten years.

Plasma proteins, cognitive decline, and 20-year risk of dementia in the Whitehall II and Atherosclerosis Risk in Communities studies

INTRODUCTION

Plasma proteins affect biological processes and are common drug targets but their role in the development of Alzheimer's disease and related dementias remains unclear. We examined associations between 4953 plasma proteins and cognitive decline and risk of dementia in two cohort studies with 20-year follow-ups.

METHODS

In the Whitehall II prospective cohort study proteins were measured using SOMAscan technology. Cognitive performance was tested five times over 20 years. Linkage to electronic health records identified incident dementia. The results were replicated in the Atherosclerosis Risk in Communities (ARIC) study.

RESULTS

Fifteen non-amyloid/non-tau-related proteins were associated with cognitive decline and dementia, were consistently identified in both cohorts, and were not explained by known dementia risk factors. Levels of six of the proteins are modifiable by currently approved medications for other conditions.

DISCUSSION

This study identified several plasma proteins in dementia-free people that are associated with long-term risk of cognitive decline and dementia.

Drug prescriptions and dementia incidence: a medication-wide association study of 17000 dementia cases among half a million participants

BACKGROUND

Previous studies have suggested that some medications may influence dementia risk. We conducted a hypothesis-generating medication-wide association study to investigate systematically the association between all prescription medications and incident dementia.

METHODS

We used a population-based cohort within the Secure Anonymised Information Linkage (SAIL) databank, comprising routinely-collected primary care, hospital admissions and mortality data from Wales, UK. We included all participants born after 1910 and registered with a SAIL general practice at ≤60 years old. Follow-up was from each participant's 60th birthday to the earliest of dementia diagnosis, deregistration from a SAIL general practice, death or the end of 2018. We considered participants exposed to a medication if they received ≥1 prescription for any of 744 medications before or during follow-up. We adjusted for sex, smoking and socioeconomic status. The outcome was any all-cause dementia code in primary care, hospital or mortality data during follow-up. We used Cox regression to calculate hazard ratios and Bonferroni-corrected p values.

RESULTS

Of 551 344 participants, 16 998 (3%) developed dementia (median follow-up was 17 years for people who developed dementia, 10 years for those without dementia). Of 744 medications, 221 (30%) were associated with dementia. Of these, 217 (98%) were associated with increased dementia incidence, many clustering around certain indications. Four medications (all vaccines) were associated with a lower dementia incidence.

CONCLUSIONS

Almost a third of medications were associated with dementia. The clustering of many drugs around certain indications may provide insights into early manifestations of dementia. We encourage further investigation of hypotheses generated by these results.

Trust and inclusion during the Covid-19 pandemic: Perspectives from Black and South Asian people living with dementia and their carers in the UK

INTRODUCTION

People from ethnic minority backgrounds living with dementia are more likely to be diagnosed later and have less access to health and social care support than their White counterparts in the United Kingdom (UK). Covid-19 has exacerbated health inequalities and diminished trust from underserved communities in the government and health services. The wider aim of the study was to explore the impact of covid-19 on Black and South-Asian people living with dementia and their carers as well as exploring the experiences of dementia care. The present paper specifically explores their views on trust and mistrust using an ecological model.

METHOD

Semi-structured interviews were conducted with 11 family carers and four people living with dementia from South Asian or Black communities living in the community. Thematic analysis was used to analyse data.

DESIGN

An exploratory qualiative design was used.

RESULTS

Four main themes were developed exploring trust at the structural, organisational, community and individual level. At the structural level, participants discussed the inequity of Covid-19, some lack of trust in the UK Government and confusion in its messaging, and the anxiety sometimes leading to curtailment of media usage. At the organisational level, there was some evidence of a perceived lack of person-centred and culturally sensitive care from healthcare professionals, as well as concerns around care homes as places of safety. At the neighbourhood community level, participants discussed both a distrust as well as a strengthening of relationships and, at the individual level, factors such as knowledge of services, identity, and faith influenced their experience of the pandemic.

CONCLUSIONS

People living with dementia need support at all levels and this study highlights how the pandemic impacted each level. Ways to improve trust in the Government and health professionals alongside culturally adapted health messaging should be explored. Alongside this, an examination of how cultural values and norms may influence help-seeking responses to dementia and increase trust in services may be helpful post-pandemic.

Dementia diagnosis in the hospital and outcomes among patients with advanced dementia documented in the Minimum Data Set

BACKGROUND

Individuals with dementia do not always have a diagnosis of dementia noted on their hospital claims. Whether this lack of documentation is associated with patient outcomes is unknown. We examined the association between a dementia diagnosis listed on a hospital claim and patient outcomes among individuals with a Minimum Data Set (MDS) assessment.

METHODS

A retrospective cohort study was conducted using administrative claims data and nursing home MDS assessments. Hospitalized patients aged 66 and older with advanced dementia noted on an MDS assessment completed within 120 days prior to their first hospitalization in 2017 were included. Advanced dementia was defined based on an MDS diagnosis of dementia, dependency in four or more activities of daily living, and a Cognitive Function Scale score indicative of moderate to severe impairment. Multilevel regression with a random intercept at the hospital level was used to examine the relationship between documentation of dementia in inpatient hospital Medicare claims and the following patient outcomes after adjusting for patient and hospital characteristics: invasive mechanical ventilation (IMV) use, intensive care unit or coronary care unit (ICU/CCU) use, 30-day mortality, and hospital length of stay (LOS).

RESULTS

In 2017, among 120,989 patients with advanced dementia and a nursing home stay, 90.57% had a dementia diagnosis on their hospital claims. In adjusted models, documentation of a dementia diagnosis was associated with lower use of the ICU/CCU (adjusted odds ratio [AOR]: 0.78 [95% confidence interval 0.74, 0.81]), use of IMV (AOR: 0.50 [0.47, 0.54]), and 30-day mortality (AOR: 0.81 [0.77, 0.85]). Patients with a dementia diagnosis had a shorter LOS.

CONCLUSIONS

Among patients with advanced dementia, those whose dementia diagnosis was documented on their inpatient hospital Medicare claim experienced lower use of ICU/CCU, use of IMV, lower 30-day mortality, and shorter LOS than those whose diagnosis was not documented.