Paola Zaninotto

Are subjective memory complaints indicative of objective cognitive decline or depressive symptoms? Findings from the English Longitudinal Study of Ageing.

BACKGROUND: Maintaining cognitive function is an important aspect of healthy ageing. In this study, we examined age trajectories of cognitive decline in a large nationally representative sample of older people in England. We explored the factors that influence such decline and whether these differed by gender.

Association of 10-year C-reactive protein trajectories with markers of healthy aging: findings from the English Longitudinal Study of Ageing.

Socio-economic trajectories and cardiovascular disease mortality in older people: the English Longitudinal Study of Ageing

Socio-economic trajectories and cardiovascular disease mortality in older people: the English Longitudinal Study of Ageing

OBJECTIVE: To examine the prospective relation between animal companionship and biomarkers of ageing in older people

Insulin-like Growth Factor 1 (IGF-1) is associated with cardiovascular disease, itself a risk factor for hearing impairment, and, in animal studies, molecular evidence suggests a role for IGF-1 in hearing function. However, the link between IGF-1 and the occurrence of hearing impairment is untested in population-based studies of humans. A total of 4390 participants aged ≥50 y (mean [SD] age 64.2 [8.0] years at baseline, 55% women) from the English Longitudinal Study of Ageing provided serum levels of IGF-1 in 2008 and again in 2012. Hearing acuity was assessed by an objective hearing test (HearCheck handheld device) in 2014 when the prevalence was 38.2%. In the full cohort, IGF-1 was not associated with subsequent hearing impairment (OR5nmol/L increase; 95% CI: 1.01; 0.94, 1.09). However, this relationship appeared to differ by age (p-value for interaction = 0.03). Thus, in younger participants (aged 50-60 y, n = 1400), IGF-1 was associated with lower odds of hearing impairment (0.86; 0.73, 1.00) after adjustment for a range of potential confounders. Among people ≥60 y (n = 2990) there was a non-significant 'J'-shaped association. Our observational evidence that higher levels of IGF-1 appeared to confer some protection against hearing impairment in some older adults warrants replication in other prospective cohort studies.

Objectives: To extend research on workforce participation beyond age 50 by describing entire employment histories in later life and testing their links to prior life course conditions.

Body mass index as a predictor of healthy and disease-free life expectancy between ages 50 and 75: a multicohort study

OBJECTIVE: To test whether the number of reports of enjoyment of life over a four year period is quantitatively associated with all cause mortality, and with death from cardiovascular disease and from other causes. DESIGN AND SETTING: Longitudinal observational population study using the English Longitudinal Study of Ageing (ELSA), a nationally representative sample of older men and women living in England. PARTICIPANTS: 9365 men and women aged 50 years or older (mean 63, standard deviation 9.3) at recruitment. MAIN OUTCOME MEASURES: Time to death, based on mortality between the third phase of data collection (wave 3 in 2006) and March 2013 (up to seven years). RESULTS: Subjective wellbeing with measures of enjoyment of life were assessed in 2002 (wave 1), 2004 (wave 2), and 2006 (wave 3). 2264 (24%) respondents reported no enjoyment of life on any assessment, with 1833 (20%) reporting high enjoyment on one report of high enjoyment of life, 2063 (22%) on two reports, and 3205 (34%) on all three occasions. 1310 deaths were recorded during follow-up. Mortality was inversely associated with the number of occasions on which participants reported high enjoyment of life. Compared with the no high enjoyment group, the hazard ratio for all cause mortality was 0.83 (95% confidence interval 0.70 to 0.99) for two reports of enjoyment of life, and 0.76 (0.64 to 0.89) for three reports, after adjustment for demographic factors, baseline health, mobility impairment, and depressive symptoms. The same association was observed after deaths occurring within two years of the third enjoyment measure were excluded (0.90 (0.85 to 0.95) for every additional report of enjoyment), and in the complete case analysis (0.90 (0.83 to 0.96)). CONCLUSIONS: This is an observational study, so causal conclusions cannot be drawn. Nonetheless, the results add a new dimension to understanding the significance of subjective wellbeing for health outcomes by documenting the importance of sustained wellbeing over time.

Hearing loss is a major cause of disability: in people over 70 years of age in the UK around two-thirds report some form of hearing loss. The social and health consequences of hearing impairment are as considerable as the economic implications for care. There is strong evidence that several age-related chronic conditions, particularly cardiovascular disease (CVD), have their origins in early life and a shared aetiology between hearing impairment and CVD has been advanced in adults. Physical stature (height) captures exposure to early life psychosocial stress, adversity, somatic illness, and nutrition, and reveals an inverse relationship with CVD but studies on hearing impairment are very scarce. We related measured height (mean measure at wave 4 [2008] and 6 [2012]) to performance on an objective hearing examination at wave 7 (2014). In an analytical sample of 4,398 there were 1,682 cases (38%) of hearing impairment. We found evidence of an inverse relationship between height and later hearing impairment, such that taller study members experienced a lower risk. The odds ratio (95% confidence interval) for the increase of 5cm in height in a fully adjusted model was 0.92 (0.87, 0.98). While low height per se is of course not a risk factor for hearing impairment, it is more likely that one or more of the characteristics that it proxies – early life diet, illness, social adversity, cognition – has a role. Future research should therefore attempt to relate these individual, prospectively gathered indicators in childhood populations to hearing impairment in later life.

Depressive disorders are a leading cause of disability in older age. Although the role of psychosocial and behavioural predictors has been well examined, little is known about the biological origins of depression. Findings from animal studies have implicated insulin-like growth factor 1 (IGF-1) in the aetiology of this disorder. A total of 6017 older adults (mean age of 65.7 years; 55% women) from the English Longitudinal Study of Ageing provided serum levels of IGF-1 (mean=15.9 nmol l(-1), s.d. 5.7) during a nurse visit in 2008. Depression symptoms were assessed in the same year and again in 2012 using the eight-item Center for Epidemiologic Studies Depression Scale. Self-reports of a physician-diagnosis of depression were also collected at both time points. In separate analyses for men and women, the results from both the cross-sectional and longitudinal analyses revealed a 'U'-shaped pattern of association, such that lower and higher levels of IGF-1 were associated with a slightly elevated risk of depression, whereas the lowest risk was seen around the median levels. Thus, in men, with the lowest quintile of IGF-1 as the referent, the age-adjusted odds ratios (95% confidence interval) of developing depression symptoms after 4 years of follow-up, for increasing quintiles of IGF-1, were: 0.51 (0.28-0.91), 0.50 (0.27-0.92), 0.63 (0.35-1.15) and 0.63 (0.35-1.13) (P-value for quadratic association 0.002). Some attenuation of these effects was apparent after adjustment for co-morbidity, socioeconomic status and health behaviours. In conclusion, in the present study of older adults, there was some evidence that moderate levels of IGF-1 levels conferred a reduced risk of depression.

Smoking, physical inactivity and obesity as predictors of healthy and disease-free life expectancy between ages 50 and 75: a multicohort study

Population ageing in Western countries has made delayed retirement and extended working life a policy priority in recent years. Retirement timing has been linked to individual factors such as health and wealth, but less is known about the role of the psychosocial work environment. This paper drew upon longitudinal data on 3462 workers aged 50-69 from five waves of the English Longitudinal Study of Ageing (ELSA). Regression models were used to assess the association of working conditions with preferred timing of retirement and actual work exit. Adjusting for a range of covariates, job demands (aspects of the job requiring sustained physical or psychological effort) were associated with preferences for earlier retirement (by 0.18 years; 95 % C.I. 0.06, 0.31). Decision authority was associated with preferences for later retirement (by 0.38 years; 95 % C.I. 0.23, 0.53) and reduced odds of work exit (OR = 0.93; 95 % C.I. 0.88, 0.97). Low recognition at work was associated with increased odds of work exit (OR = 1.23; 95 % C.I. 1.10, 1.43). There was little evidence of any interactive relationship between demands and resources. Efforts to extend working life should address issues relating to the immediate psychosocial work environment. Providing older workers with increased sense of control, and ensuring contributions are adequately recognised, may delay retirement intentions and the timing of labour market exit.

Authors reply: Duration of depressive symptoms significantly related to increase in mortality

We examined the little-tested associations between general cognitive function in middle and older age and later risk of death from chronic diseases. In the English Longitudinal Study of Ageing (2002-2012), 11,391 study participants who were 50-100 years of age at study induction underwent a battery of cognitive tests and provided a range of collateral data. In an analytical sample of 9,204 people (4,982 women), there were 1,488 deaths during follow-up (mean duration, 9.0 years). When we combined scores from 4 cognition tests that represented 3 acknowledged key domains of cognitive functioning (memory, executive function, and processing speed), cognition was inversely associated with deaths from cancer (per each 1-standard-deviation decrease in general cognitive function score, hazard ratio = 1.21, 95% CI: 1.10, 1.33), cardiovascular disease (hazard ratio = 1.71, 95% CI: 1.55, 1.89), other causes (hazard ratio = 2.07, 95% CI: 1.79, 2.40), and respiratory illness (hazard ratio = 2.48, 95% CI: 2.12, 2.90). Controlling for a range of covariates, such as health behaviors and socioeconomic status, and left-censoring to explore reverse causality had very little impact on the strength of these relationships. These findings indicate that cognitive test scores can provide relatively simple indicators of the risk of death from an array of chronic diseases and that these associations appear to be independent of other commonly assessed risk factors.

Abstract We examined the association between lifecourse socioeconomic status (SES) and the risk of type 2 diabetes at older ages, ascertaining the extent to which adult lifestyle factors and systemic inflammation explain this relationship. Data were drawn from the English Longitudinal Study of Ageing (ELSA) which, established in 2002, is a representative cohort study of ≥50-year olds individuals living in England. SES indicators were paternal social class, participants' education, participants' wealth, and a lifecourse socioeconomic index. Inflammatory markers (C-reactive protein and fibrinogen) and lifestyle factors were measured repeatedly; diabetes incidence (new cases) was monitored over 7.5 years of follow-up. Of the 6218 individuals free from diabetes at baseline (44% women, mean aged 66 years), 423 developed diabetes during follow-up. Relative to the most advantaged people, those in the lowest lifecourse SES group experienced more than double the risk of diabetes (hazard ratio 2.59; 95% Confidence Interval (CI) = 1.81-3.71). Lifestyle factors explained 52% (95%CI:30-85) and inflammatory markers 22% (95%CI:13-37) of this gradient. Similar results were apparent with the separate SES indicators. In a general population sample, socioeconomic inequalities in the risk of type 2 diabetes extend to older ages and appear to partially originate from socioeconomic variations in modifiable factors which include lifestyle and inflammation.

Duration of depressive symptoms and mortality risk: the English Longitudinal Study of Ageing (ELSA)

Gender-specific changes in well-being in older people with coronary heart disease: evidence from the English Longitudinal Study of Ageing