Low medically certified sickness absence among employees with poor health status predicts future health improvement: the Whitehall II study

Background: High sickness absence is associated with poor health status, but it is not known whether low levels of sickness absence among people with poor health predict future health improvement. Objective: To examine the association between medically certified sickness absence and subsequent change in health among initially unhealthy employees.Methods: 5210 employees (3762 men, 1448 women) whose self-rated health status remained stable (either good or poor) between data phases 1 and 2 were divided into three groups according to their rate of medically certified absences during this period (0 vs >0-5 vs >5 absence spells longer than 7 days per 10 person-years). Subsequent change in health status was determined by self-rated health at follow-up (phase 3).Results: After adjustment for age and sex, there was a strong contemporaneous association between lower sickness absence and better health status. Among participants reporting poor health, low absence was associated with subsequent improvement in health status (odds ratio 2.66, 95% CI 1.78 to 4.02 for no absence vs >5 certified spells per 10 years). This association was only partially explained by known existing morbidity, socioeconomic position and risk factors.Conclusions: Low levels of medically certified sickness absence seem to be associated with positive change in health status among employees in poor health. Further research is needed to examine whether lower sickness absence also marks a more favourable prognosis for specific diseases

Physical Activity and Adiposity Markers at Older Ages: Accelerometer Vs Questionnaire Data

Physical activity is critically important for successful aging, but its effect on adiposity markers at older ages is unclear as much of the evidence comes from self-reported data on physical activity. We assessed the associations of questionnaire-assessed and accelerometer-assessed physical activity with adiposity markers in older adults

Dietary pattern, inflammation and cognitive decline: The Whitehall II prospective cohort study

BACKGROUND & AIMS: Low-grade inflammation appears to play an etiological role in cognitive decline. However the association between an inflammatory dietary pattern and cognitive decline has not been investigated. We aimed to investigate dietary patterns associated with inflammation and whether such diet is associated with cognitive decline. METHODS: We analyzed 5083 participants (28.7% women) from the Whitehall II cohort study. Diet and serum interleukin-6 (IL-6) were assessed in 1991-1993 and 1997-1999. We used reduced rank regression methods to determine a dietary pattern associated with elevated IL-6. Cognitive tests were performed in 1997-1999 and repeated in 2002-2004 and 2007-2009. The association between dietary pattern and cognitive decline between ages 45 and 79 was assessed using linear mixed models. RESULTS: We identified an inflammatory dietary pattern characterized by higher intake of red meat, processed meat, peas and legumes, and fried food, and lower intake of whole grains which correlated with elevated IL-6 both in 1991-1993 and 1997-1999. A greater decline in reasoning was seen in participants in the highest tertile of adherence to the inflammatory dietary pattern (-0.37 SD; 95% confidence interval [CI] -0.40, -0.34) compared to those in the lowest tertile (-0.31; 95% CI -0.34, -0.28) after adjustment for age, sex, ethnicity, occupational status, education, and total energy intake (p for interaction across tertiles = 0.01). This association remained significant after multivariable adjustment. Similarly for global cognition, the inflammatory dietary pattern was associated with faster cognitive decline after multivariable adjustment (p for interaction across tertiles = 0.04). Associations were stronger in younger participants (<56 years), reducing the possibility of reverse causation. CONCLUSIONS: Our study found that a dietary pattern characterized as higher intake of red and processed meat, peas, legumes and fried food, and lower intake of whole grains was associated with higher inflammatory markers and accelerated cognitive decline at older ages. This supports the case for further research

Metabolic Syndrome Over 10 Years and Cognitive Functioning in Late Midlife: The Whitehall II study

International audienceOBJECTIVE: Evidence that the metabolic syndrome is a risk factor for poor cognition is mixed and is focused mainly on the elderly population; rarely is an adjustment made for socioeconomic factors. We examined this association in late midlife, with particular focus on cumulative effects and the role of socioeconomic circumstances. RESEARCH DESIGN AND METHODS: Analyses were performed for 4,150 white participants from the Whitehall II study. Metabolic syndrome, using the National Cholesterol Education Program Adult Treatment Panel III criteria, was assessed three times over the 10-year follow-up (1991-2001). Cognitive function was assessed using a battery of six tests at the end of the follow-up. RESULTS: After adjustment for demographic variables, health behaviors, and health status, participants with persistent metabolic syndrome (at least two of the three screenings) over the 10-year follow-up had lower cognitive performance than participants who never had metabolic syndrome. No significant differences in cognitive function were observed between participants with nonpersistent metabolic syndrome (one of the three screenings) and those who never had metabolic syndrome during the follow-up. Adjustment for adult occupational position attenuated this association by between 41 and 86%, depending on the measure of cognitive function. Adjustment for education had little effect. CONCLUSIONS: Only persistent metabolic syndrome was associated with lower cognitive performance in late midlife. Adult occupational position but not education had a substantial impact on this association; these results highlight the importance of adult socioeconomic circumstances in identifying and targeting risk factors for cognitive aging

Marriage and risk of dementia: systematic review and meta-analysis of observational studies

BACKGROUND: Being married is associated with healthier lifestyle behaviours and lower mortality and may reduce risk for dementia due to life-course factors. We conducted a systematic review and meta-analysis of studies of the association between marital status and the risk of developing dementia. METHODS: We searched medical databases and contacted experts in the field for relevant studies reporting the relationship, adjusted for age and sex, between marital status and dementia. We rated methodological quality and conducted random-effects meta-analyses to summarise relative risks of being widowed, divorced or lifelong single, compared with being married. Secondary stratified analyses with meta-regression examined the impact of clinical and social context and study methodology on findings. RESULTS: We included 15 studies with 812 047 participants. Compared with those who are married, lifelong single (relative risk=1.42 (95% CI 1.07 to 1.90)) and widowed (1.20 (1.02 to 1.41)) people have elevated risk of dementia. We did not find an association in divorced people. Further analyses showed that less education partially confounds the risk in widowhood and worse physical health the elevated risk in lifelong single people. Compared with studies that used clinical registers for ascertaining dementia diagnoses, those which clinically examined all participants found higher risk for being unmarried. CONCLUSIONS: Being married is associated with reduced risk of dementia than widowed and lifelong single people, who are also underdiagnosed in routine clinical practice. Dementia prevention in unmarried people should focus on education and physical health and should consider the possible effect of social engagement as a modifiable risk factor

Facteurs de risque de la maladie d’Alzheimer et des maladies apparentées : approche parcours de vie = Risk factors for Alzheimer's disease and related dementia: A lifecourse approach

Alzheimer's disease and related dementias are devastating for the individual and their entourage, they also carry tremendous financial burden for society at large. Age is the principal risk factor, with the risk doubling every 5 years after the age of 65 years. Research has clearly established that pathophysiological changes occur ten to fifteen years before the diagnosis of disease. This has implications for understanding risk and protective factors of the disease as most longitudinal studies were set up in adults over 65 years of age at the start of the study and the follow-up for incidence of Alzheimer's disease is often less than ten years. Thus, the results from such studies are likely to be biased by reverse causation. This has led to inconsistent findings in studies and a varying list of risk and protective factors produced by various guidelines published in recent years. In this paper, we describe these challenges and propose the use of a lifecourse approach for the identification of risk and protective factors. We also highlight the need to extend research on biomarkers to peripheral biomarkers; proteomics, in particular, as they reflect both genetic and environmental effects and are potentially modifiable

Longitudinal associations between diurnal cortisol variation and later-life cognitive impairment

Objective: To determine whether HPAA dysfunction is prospectively associated with global cognitive impairment in later life Methods: This cross-cohort study integrates two large longitudinal datasets: Whitehall II and the National Survey for Health and Development (NSHD), on data collected in the Whitehall II study in 2002/2004, 2007/2009 and 2012/2013; and for NSHD in 2006/2010 and 2015. Serial salivary cortisol samples were collected multiple times within a 24-hour period at mean ages 61.2 and 65.9 years in Whitehall II and at age 60-64 from NSHD participants. Cortisol profile is defined using cortisol awakening response (CAR) and am:pm ratio. Cognitive function was measured using the MMSE in Whitehall II and ACE-III in NSHD, harmonised into a thirty-point score. Models were adjusted for age, sex, diagnoses of hypertension, diabetes, BMI, educational attainment and interval between HPAA and cognitive assessments. Results: In fully adjusted models, increased am:pm cortisol ratio was prospectively associated with better later-life cognitive function years later (0.02 fewer errors per SD increase in am:pm cortisol ratio, p<0.01) and verbal fluency (0.03 SD increase in verbal fluency per SD increase in am:pm ratio, p<0.01). Increasing age, lower educational attainment, diagnosis of hypertension, diagnosis of diabetes and increased BMI were associated with worse cognitive function and poorer verbal fluency. There were no associations between depression and later-life cognition or reverse associations between cognition and later-life cortisol profiles. Conclusions: Loss of diurnal HPAA variation is evident in individuals subsequently experiencing more cognitive impairment. It may serve as an early pre-clinical marker of cognitive decline

No evidence of a longitudinal association between diurnal cortisol patterns and cognition

We examined the effect of salivary cortisol on cognitive performance and decline in 3229 adults (79% men), mean age 61years. Six saliva samples over the day along with a cognition test battery were administered twice in 5years. In fully-adjusted cross-sectional analyses from 2002 to 2004, higher waking cortisol was associated with higher reasoning score (β= 0.08, 95% confidence interval: 0.01, 0.15) but this finding was not replicated using data from 2007 to 2009. Over the mean 5years follow-up there was decline in all cognitive tests but this decline did not vary as a function of cortisol levels; the exception was among APOE e4 carriers where a flatter diurnal slope and higher bedtime cortisol were associated with faster decline in verbal fluency. Changes in cortisol measures between 2002/2004 and 2007/2009 or chronically elevated levels were not associated with cognitive performance in 2007/2009. These results, based on a large sample of community-dwelling adults suggest that variability in hypothalamic-pituitary-adrenal function is not a strong contributor to cognitive aging. © 2014 The Authors