Key PointsQuestionWhat is the association between various socioeconomic markers and dementia incidence?FindingsThis longitudinal cohort study found that lower wealth in late life, but not education, was associated with increased risk for dementia, suggesting that people with fewer financial resources were at higher risk. No substantive differences were identified in relation to the area of neighborhood deprivation; an age-cohort effect was observed, highlighting that socioeconomic inequalities were more robust among people born in later years.MeaningThe association between socioeconomic status and dementia incidence in a contemporary cohort of older adults may be driven by wealth rather than education.

ObjectivesTo determine whether hearing loss is associated with incident physician‐diagnosed dementia in a representative sample.DesignRetrospective cohort study.SettingEnglish Longitudinal Study of Ageing.ParticipantsAdults aged 50 and older.MeasurementsCross‐sectional associations between self‐reported (n = 7,865) and objective hearing measures (n = 6,902) and dementia were examined using multinomial‐logistic regression. The longitudinal association between self‐reported hearing at Wave 2 (2004/05) and cumulative physician‐diagnosed dementia up to Wave 7 (2014/15) was modelled using Cox proportional hazards regression.ResultsAfter adjustment for potential confounders, in cross‐sectional analysis, participants who had self‐reported or objective moderate and poor hearing were more likely to have a dementia diagnosis than those with normal hearing (self‐reported: odds ratio OR = 1.6, 95% CI = 1.1–2.4 moderate hearing; OR = 2.6, 95% CI = 1.7–3.9 poor hearing, objective: OR = 1.6, 95% CI = 1.0–2.8 moderate hearing; OR = 4.4, 95% CI = 1.9–9.9 poor hearing). Longitudinally, the hazard of developing dementia was 1.4 (95% CI = 1.0–1.9) times as high in individuals who reported moderate hearing and 1.6 (95% CI = 1.1–2.0) times as high in those who reported poor hearing.ConclusionOlder adults with hearing loss are at greater risk of dementia than those with normal hearing. These findings are consistent with the rationale that correction of hearing loss could help delay the onset of dementia, or that hearing loss itself could serve as a risk indicator for cognitive decline.

ObjectiveThis study investigated associations between informal caregiving and exit from paid employment among older workers in the United Kingdom.MethodInformation on caregiving and work status for 8,473 older workers (aged 50–75 years) was drawn from five waves of Understanding Society (2009–2014). We used discrete-time survival models to estimate the associations of caring intensity and type on the probability of exiting paid work (from >0 to 0 hours/week) in the following year. Models were stratified by sex and working hours, and adjusted for age, self-rated health, long-standing illness, occupation, and partner’s employment status.ResultsNo association was found between caregiving intensity and exit from paid work. Full-time employees who provided care within the household (women and men) or cared for a partner/spouse (women only) more likely to stop working, compared to those not providing care. Women who entered a caregiving role (more than 10 hours/week) were between 2.64 (95% confidence interval [CI]: 1.46, 4.79) and 4.46 (95% CI: 2.53, 7.88) times more likely to exit work (for part-time and full-time workers, respectively), compared to women providing no care.DiscussionThis study highlights the onset of caregiving as a key period for older workers. Ensuring that caregiving responsibilities are adequately recognized and supported may help extend working life.

The aim of this study was to determine whether frailty in older adults is associated with the risk of subsequent dementia. A total of 8,722 older adults from the English Longitudinal Study of Ageing were followed-up every two years until they reported a diagnosis of dementia, died, or were right censored. Frailty was defined using a frailty index comprised of 47 health deficits. To test if cognitive function influences the relationship between frailty and incident dementia, the analyses were repeated according to lower or upper three quartiles of baseline cognitive function. Competing risks regression and Cox proportional hazard models were used to evaluate whether the degree of baseline frailty was associated with incident dementia. Compared with non-frail participants, pre-frail (HR: 1.51 95%CI [1.12–2.02]) and frail participants (HR: 1.73 95%CI [1.22–2.43]) had a higher risk of developing dementia, after adjustment for covariates. The association between frailty and incident dementia was significant for adults in the upper three quartiles of global cognitive function (HR: 3.48 95%CI [1.98–6.12]), but not for adults who were in the lowest quartile of cognitive function (HR: 1.13 95%CI [0.74–1.71]). Frailty should be monitored alongside cognitive functioning when assessing risk factors for dementia in older adults.

Background: Differences in dementia risk across the gradient of socioeconomic status (SES) exist, but their determinants are not well understood. Objective: This study investigates whether health conditions and lifestyle-related risk factors explain the SES inequalities in dementia risk. Methods: 6,346 participants from the English Longitudinal Study of Ageing were followed up from 2008/2009 until 2014/2015. We used Cox regression adjusted for age, gender, wealth/education, and clustering at the household level to examine the association between SES markers (wealth, education) and time to dementia in a structural equation model including potential mediation or effect modification by a weighted compound score of twelve modifiable risk and protective factors for dementia ('LIfestyle for BRAin health' (LIBRA) score). Results: During a median follow-up of 6 years, 192 individuals (3.0%) developed dementia. LIBRA scores decreased with increasing wealth and higher educational level. A one-point increase in the LIBRA score was associated with a 13% increase in dementia risk (hazard ratio (HR) = 1.13, 95% confidence interval 1.07-1.19). Higher wealth was associated with a decreased dementia risk (HR = 0.58, 0.39-0.85). Mediation analysis showed that 52% of the risk difference between the highest and lowest wealth tertile was mediated by differences in LIBRA (indirect effect: HR = 0.75, 0.66-0.85). Education was not directly associated with dementia (HR = 1.05, 0.69-1.59), but was a distal risk factor for dementia by explaining differences in wealth and LIBRA scores (indirect effect high education: HR = 0.92, 0.88-0.95). Conclusion: Socioeconomic differences in dementia risk can be partly explained by differences in modifiable health conditions and lifestyle factors.

SummaryTheories of cognitive reserve, disuse syndrome and stress have suggested that activities that are mentally engaging, enjoyable and socially interactive could be protective against the development of dementia. Using data from the English Longitudinal Study of Ageing, this study shows that for adults aged 50 and older visiting museums every few months or more was associated with a lower incidence rate of dementia over a 10-year follow-up period compared with less-frequent visiting. This association was independent of demographics, socioeconomic status, health-related variables including sensory impairment, depression, vascular conditions and other forms of community engagement. Visiting museums may be a promising psychosocial activity to support the prevention of dementia.Declaration of interestNone.

BackgroundAs the population ages, cognitive decline and dementia have become major health concerns in the UK. Loneliness has been linked to cognitive decline, but the reverse causality of this association remains unclear. This study aims to examine whether there is a bidirectional relationship between loneliness and cognitive function in older English adults (age 50 years and over) over a 10-year follow-up.MethodsData came from a nationally representative sample of 5885 participants in the English Longitudinal Study of Ageing (ELSA), free of stroke or dementia and followed every 2 years up to wave 7 (2014–15). At each wave, cognitive function was measured with word recall and verbal fluency tests, and loneliness was measured with the abridged version of the revised UCLA Loneliness Scale. Bivariate dual change score models were used to assess the multivariate associations between loneliness and cognitive function, used interchangeably as exposures and outcomes.ResultsGreater loneliness at baseline was associated with poorer memory [β intercept = −0.03, standard error (SE) = 0.01, P  =  0.016] and verbal fluency (β intercept = −0.01, SE  =  001, P =  0.027) at baseline, and with a stronger linear rate of decline in both memory (β linear slope = −0.07, SE  =  001, P  ≤ 0.001) and verbal fluency (β linear slope = −0.09, SE  =  0.03, P =  0.003) over a 10-year follow-up period, although the performance on verbal fluency did not change substantially on average over this period. We also found that higher baseline memory, but not verbal fluency, predicted a slower change in loneliness (β linear slope = −0.01, SE  =  001, P =  0.004) and that a linear decline in memory was associated with an acceleration in loneliness (β quadratic slope = −0.02, SE  =  001, P  ≤ 0.001) during follow-up.ConclusionsHigher loneliness is associated with poorer cognitive function at baseline and contributes to a worsening in memory and verbal fluency over a decade. These factors seem, however, to be partially intertwined, since baseline memory and its rate of decline also contribute to an increase in loneliness over time.

Background Several risk factors contribute to dementia, but the role of obesity remains unclear. This study investigated whether increased body weight or central obesity were associated with a higher risk of developing dementia in a representative sample of older English adults. Methods We studied 6582 participants from the English Longitudinal Study of Ageing (ELSA) who were aged ≥50 years and were dementia-free at baseline, that being either wave 1 (2002–2003) for study members who started at wave 1, or at either wave 2 (2004–2005) or 4 (2008–2009) for those who began the study as refreshment samples. Body mass index (BMI) was measured at baseline and categorized into normal weight (18.5–24.9 kg/m2), overweight (25–29.9 kg/m2) and obese (≥30 kg/m2). Central obesity was defined as a waist circumference (WC) >88 cm for women and >102 cm for men. Cumulative incidence of dementia was ascertained based on physician-diagnosed dementia, an overall score >3.38 on the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) and Hospital Episodes Statistics (HES) data at every ELSA wave from baseline until wave 8 (2016–2017). Cox proportional hazards models were used to assess the association between baseline BMI levels or abdominal obesity in relation to dementia incidence during the mean follow-up period of 11 years. Results From the overall sample, 6.9% (n = 453) of participants developed dementia during the follow-up period of maximum 15 years (2002–2017). Compared with participants with normal weight, those who were obese at baseline had an elevated risk of dementia incidence [hazard ratio (HR) = 1.34, 95% confidence interval (CI) 1.07–1.61] independent of sex, baseline age, apolipoprotein E-ε4 (APOE-ε4), education, physical activity, smoking and marital status. The relationship was slightly accentuated after additionally controlling for hypertension and diabetes (HR = 1.31, 95% CI 1.03–1.59). Women with central obesity had a 39% greater risk of dementia compared with non-central obese women (HR = 1.39, 95% CI 1.12–1.66). When compared with a normal BMI and WC group, the obese and high WC group had 28% (HR = 1.28, 95% CI 1.03–1.53) higher risk of dementia. Conclusions Our results suggest that having an increased body weight or abdominal obesity are associated with increased dementia incidence. These findings have significant implications for dementia prevention and overall public health.