Wrist-worn accelerometers are increasingly being used for the assessment of physical activity in population studies, but little is known about their value for sleep assessment. We developed a novel ...method of assessing sleep duration using data from 4,094 Whitehall II Study (United Kingdom, 2012-2013) participants aged 60-83 who wore the accelerometer for 9 consecutive days, filled in a sleep log and reported sleep duration via questionnaire. Our sleep detection algorithm defined (nocturnal) sleep as a period of sustained inactivity, itself detected as the absence of change in arm angle greater than 5 degrees for 5 minutes or more, during a period recorded as sleep by the participant in their sleep log. The resulting estimate of sleep duration had a moderate (but similar to previous findings) agreement with questionnaire based measures for time in bed, defined as the difference between sleep onset and waking time (kappa = 0.32, 95%CI:0.29,0.34) and total sleep duration (kappa = 0.39, 0.36,0.42). This estimate was lower for time in bed for women, depressed participants, those reporting more insomnia symptoms, and on weekend days. No such group differences were found for total sleep duration. Our algorithm was validated against data from a polysomnography study on 28 persons which found a longer time window and lower angle threshold to have better sensitivity to wakefulness, while the reverse was true for sensitivity to sleep. The novelty of our method is the use of a generic algorithm that will allow comparison between studies rather than a "count" based, device specific method.
Background
Living alone has been associated with increased mortality risk, but it is unclear whether this is a result of a selection effect or the impact of stressful life changes such as widowhood ...or divorce leading to changes in living arrangements. We therefore examined the association between living alone, transitions in living arrangements and all-cause mortality.
Method
We analysed data from 4,888 individuals who participated in both wave 2 (2004–2005) and wave 4 (2008–2009) of the English Longitudinal Study of Ageing. Transitions in living arrangements over this period were identified. Mortality status was ascertained from linked national mortality registers. Cox proportional hazards analysis was used to examine the association between living alone and mortality over an average 8.5 year follow-up period.
Results
An association was found between living alone at wave 4 and mortality (hazard ratio (HR): 1.20, 95% CI 1.04–1.38) in a model adjusted for multiple factors including socioeconomic status, physical health, health behaviours and loneliness. We also found that participants who moved to living alone after divorce or bereavement had a higher risk of mortality compared with those who lived with others at both time points (HR: 1.34, 95% CI 1.01–1.79), while those who moved to living alone for other reasons did not show an increased mortality risk.
Conclusions
The relationship between living alone and mortality is complicated by the reasons underlying not living with others. A greater understanding of these dynamics will help to identify the individuals who are at particular health risk because of their living arrangements.
Highlights • Hair samples present considerable opportunities for assessing cortisol in cohorts. • Certain hair characteristics correlate with hair cortisol concentrations (HCC). • Mental and physical ...health status is independently associated with HCC.
Abstract
Aims
To examine associations of diastolic and systolic blood pressure (SBP) at age 50, 60, and 70 years with incidence of dementia, and whether cardiovascular disease (CVD) over the ...follow-up mediates this association.
Methods and results
Systolic and diastolic blood pressure were measured on 8639 persons (32.5% women) from the Whitehall II cohort study in 1985, 1991, 1997, and 2003. Incidence of dementia (n dementia/n total = 385/8639) was ascertained from electronic health records followed-up until 2017. Cubic splines using continuous blood pressure measures suggested SBP ≥130 mmHg at age 50 but not at age 60 or 70 was associated with increased risk of dementia, confirmed in Cox regression analyses adjusted for sociodemographic factors, health behaviours, and time varying chronic conditions hazard ratio (HR) 1.38; 95% confidence interval (95% CI) 1.11, 1.70. Diastolic blood pressure was not associated with dementia. Participants with longer exposure to hypertension (SBP ≥ 130 mmHg) between mean ages of 45 and 61 years had an increased risk of dementia compared to those with no or low exposure to hypertension (HR 1.29, 95% CI 1.00, 1.66). In multi-state models, SBP ≥ 130 mmHg at 50 years of age was associated with greater risk of dementia in those free of CVD over the follow-up (HR 1.47, 95% CI 1.15, 1.87).
Conclusion
Systolic blood pressure ≥130 mmHg at age 50, below the conventional ≥140 mmHg threshold used to define hypertension, is associated with increased risk of dementia; in these persons this excess risk is independent of CVD.
Highlights • Recurrent short sleep duration is associated with flatter slope in diurnal cortisol. • Chronic insomnia symptoms predict a steeper morning rise in cortisol.
Abstract
Background
Falls in later life that require admission to hospital have well-established consequences for future disability and health. The likelihood and severity of a fall will result from ...the presence of one or more risk factors. The aim of this study is to examine risk factors identified for their ability to prevent falls and to assess whether they are associated with hospital admission after a fall.
Methods
Analyses of data from the English Longitudinal Study of Aging (ELSA), a prospective cohort study. In a sample of 3783 men and women older than 60 years old, a range of potential risk factors measured at Wave 4 (demographic, social environment, physical, and mental functioning) were examined as predictors of fall-related hospitalizations, identified using International Classification of Diseases, 10th Revision (ICD-10) code from linked hospital records in the United Kingdom. Subdistribution hazard models were used to account for competing risk of death.
Results
Several risk factors identified by previous work were confirmed. Suffering from urinary incontinence (subdistribution hazard ratio = 1.49; 95% CI: 1.14, 1.95) and osteoporosis (subdistribution hazard ratio = 1.48; 95% CI: 1.05, 2.07), which are not commonly considered at an early stage of screening, were found to be associated with hospital admission after a fall. Both low and moderate levels of physical activity were also found to somewhat increase the risk of hospital admission after a fall.
Conclusions
Several predictors of having a fall, severe enough to require hospital admission, have been confirmed. In particular, urinary incontinence should be considered at an earlier point in the assessment of risk.
Health inequalities persist into old age. We aimed to investigate risk factors for socioeconomic differences in frailty that could potentially be modified through policy measures.
In this multi-wave ...longitudinal cohort study (Whitehall II study), we assessed participants' socioeconomic status, behavioural and biomedical risk factors, and disease status at age 45–55 years, and frailty (defined according to the Fried phenotype) at baseline and at one or more of three clinic visits about 18 years later (mean age 69 years SD 5·9). We used logistic mixed models to examine the associations between socioeconomic status and risk factors at age 50 years and subsequent prevalence of frailty (adjusted for sex, ethnic origin, and age), with sensitivity analyses and multiple imputation for missing data.
Between Sept 9, 2007, and Dec 8, 2016, 6233 middle-aged adults were measured for frailty. Frailty was present in 562 (3%) of 16 164 person-observations, and varied by socioeconomic status: 145 (2%) person-observations had high socioeconomic status, 241 (4%) had intermediate status, and 176 (7%) had low socioeconomic status, adjusting for sex and age. Risk factors for frailty included cardiovascular disease, depression, smoking, high or abstinent alcohol consumption, low fruit and vegetable consumption, physical inactivity, poor lung function, hypertension, and overweight or obesity. Cardiometabolic markers for future frailty were high ratio of total to high-density lipoprotein cholesterol, and raised interleukin-6 and C-reactive protein concentrations. The five most important factors contributing to the frailty gradient, assessed by percent attenuation of the association between socioeconomic status and frailty, were physical activity (13%), interleukin-6 (13%), body-mass index category (11%), C-reactive protein (11%), and poor lung function (10%). Overall, socioeconomic differences in frailty were reduced by 40% in the maximally-adjusted model compared with the minimally-adjusted model.
Behavioural and cardiometabolic risk factors in midlife account for more than a third of socioeconomic differences in frailty. Our findings suggest that interventions targeting physical activity, obesity, smoking, and low-grade inflammation in middle age might reduce socioeconomic differences in later-life frailty.
British Heart Foundation and British Medical Research Council.
Pedestrian crossings in the UK and US require people to walk at 1.2m/s to cross the road in time; however a large proportion of older people do not walk this fast, potentially discouraging walking or ...putting older people at risk of injury. We use longitudinal data to investigate changes in walking speed, and ability to cross the road in time, at older ages.
31,015 walking speed measurements were taken from 10,249 men and women aged 60+ years in waves 1–7 of the English Longitudinal Study of Ageing (2002–2014). Growth curve analyses were used to model how walking speed changes with increasing age, and predicted probabilities of being able to cross the road in time were estimated.
10% of measured walking speeds were fast enough to cross the road in time. Walking speed declined with age (−5.7×10−3m/s/yr (95% CI −7.6×10−3, −3.9×10−3)), and the decline accelerated with increasing age (−0.3 ×10−3m/s/yr (−0.4 ×10−3, −0.3 ×10−3)). Female, less wealthy and less healthy older people had slower walking speeds. For instance, predicted probability of crossing the road in time at age 60 was 14.8% (10.1, 18.5) and 2.7% (1.5, 3.8) for the richest and poorest men and 8.4% (6.0, 1.1) and 1.5% (0.9, 2.2) for the richest and poorest women, and at age 80 they were 7.1% (3.6, 10.5) and 1.0% (0.3, 1.7) for the richest and poorest men and 3.7% (1.6, 5.9) and 0.5% (0.1, 0.9) for the richest and poorest women.
Most older people do not walk fast enough to cross the road in time. Even the majority of the wealthiest and healthiest people aged 60 years and older do not walk fast enough to cross pedestrian crossings in the allocated time. Crossing times should be increased to allow for older peoples’ slower walking speeds or other policies considered to improve walkability, and to help avoid injuries and social isolation.
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