Martin J. Shipley

Employment grade and coronary heart disease in British civil servants.

The relationship between grade of employment, coronary risk factors, and coronary heart disease (CHD) mortality has been investigated in a longitudinal study of 17 530 civil servants working in London. After seven and a half years of follow-up there was a clear inverse relationship between grade of employment and CHD mortality. Men in the lowest grade (messengers) had 3.6 times the CHD mortality of men in the highest employment grade (administrators). Men in the lower employment grades were shorter, heavier for their height, had higher blood pressure, higher plasma glucose, smoked more, and reported less leisure-time physical activity than men in the higher grades. Yet when allowance was made for the influence on mortality of all of these factors plus plasma cholesterol, the inverse association between grade of employment and CHD mortality was still strong. It is concluded that the higher CHD mortality experienced by working class men, which is present also in national statistics, can be only partly explained by the established coronary risk factors.

Sickness absence as a measure of health status and functioning: from the UK Whitehall II study.

STUDY OBJECTIVE--To investigate the relationship between self reported health status and sickness absence. DESIGN--Analysis of questionnaire and sickness absence data from the first phase of the Whitehall II study--a longitudinal study set up to investigate the degree and causes of the social gradient in morbidity and mortality. SETTING--London offices of 20 civil service departments. PARTICIPANTS--Altogether 6895 male and 3413 female civil servants aged 35-55 years. Analysis was conducted on 88% of participants who had complete data for the present analysis. MAIN RESULTS--A strong inverse relation between the grade of employment (measure of socioeconomic status) and sickness absence was observed. Men in the lowest grade had rates of sickness absence six times higher than those in the highest grade. For women the corresponding differences were two to five times higher. In general, the longer the duration of absence, the more strongly did baseline health predict rates of absence. However, the health measures also predicted shorter spells, although to a lesser extent. Job satisfaction was strongly related to sickness absence with higher rates in those who reported low job satisfaction. After adjusting for health status the association remained for one to two day absences, but was greatly reduced for absences longer than three days. CONCLUSION--There was a strong association between ill health and sickness absence, particularly for longer spells. The magnitude of the association may have been underestimated because of the strength of the association between grade of employment and sickness absence. It is proposed that sickness absence be used as an integrated measure of physical, psychological, and social functioning in studies of working populations.

High Blood Glucose Concentration Is a Risk Factor for Mortality in Middle-Aged Nondiabetic Men 20-year follow-up in the Whitehall Study, the Paris Prospective Study, and the Helsinki Policemen Study

OBJECTIVE To assess the association between high but nondiabetic blood glucose levels and the risk of death from all causes, coronary heart disease (CHD), cardiovascular disease, and neoplasms. RESEARCH DESIGN AND METHODS We studied the 20-year mortality of non-diabetic, working men, age 44–55 years, in three European cohorts known as the Whitehall Study (n = 10,025), the Paris Prospective Study (n = 6,629), and the Helsinki Policeman Study (n = 631). These men were identified by their 2-h glucose levels following an oral glucose tolerance test and by the absence of a prior diagnosis of diabetes. As the protocol for the oral glucose tolerance test and methods for measuring glucose differed between studies, mortality was analyzed according to the percentiles of the 2-h and fasting glucose distributions, using the Coxs proportional hazards model. RESULTS Men in the upper 20% of the 2-h glucose distributions and those in the upper 2.5% for fasting glucose had a significantly higher risk of all-cause mortality in comparison with men in the lower 80% of these distributions, with age-adjusted hazard ratios of 1.6 (95% CI 1.4–1.9) and 2.0 (1.6–2.6) for the upper 2.5%. For death from cardiovascular and CHD, men in the upper 2.5% of the 2-h and fasting glucose distributions were at higher risk, with age-adjusted hazard ratios for CHD of 1.8 (1.4–2.4) and 2.7 (1.7–4.4), respectively. CONCLUSIONS If early intervention aimed at lowering blood glucose concentrations can be shown to reduce mortality, it may be justified to lower the levels of both 2-h and fasting glucose, which define diabetes.

Association of Socioeconomic Position With Health Behaviors and Mortality

CONTEXT Previous studies may have underestimated the contribution of health behaviors to social inequalities in mortality because health behaviors were assessed only at the baseline of the study. OBJECTIVE To examine the role of health behaviors in the association between socioeconomic position and mortality and compare whether their contribution differs when assessed at only 1 point in time with that assessed longitudinally through the follow-up period. DESIGN, SETTING, AND PARTICIPANTS Established in 1985, the British Whitehall II longitudinal cohort study includes 10 308 civil servants, aged 35 to 55 years, living in London, England. Analyses are based on 9590 men and women followed up for mortality until April 30, 2009. Socioeconomic position was derived from civil service employment grade (high, intermediate, and low) at baseline. Smoking, alcohol consumption, diet, and physical activity were assessed 4 times during the follow-up period. MAIN OUTCOME MEASURES All-cause and cause-specific mortality. RESULTS A total of 654 participants died during the follow-up period. In the analyses adjusted for sex and year of birth, those with the lowest socioeconomic position had 1.60 times higher risk of death from all causes than those with the highest socioeconomic position (a rate difference of 1.94/1000 person-years). This association was attenuated by 42% (95% confidence interval [CI], 21%-94%) when health behaviors assessed at baseline were entered into the model and by 72% (95% CI, 42%-154%) when they were entered as time-dependent covariates. The corresponding attenuations were 29% (95% CI, 11%-54%) and 45% (95% CI, 24%-79%) for cardiovascular mortality and 61% (95% CI, 16%-425%) and 94% (95% CI, 35%-595%) for noncancer and noncardiovascular mortality. The difference between the baseline only and repeated assessments of health behaviors was mostly due to an increased explanatory power of diet (from 7% to 17% for all-cause mortality, respectively), physical activity (from 5% to 21% for all-cause mortality), and alcohol consumption (from 3% to 12% for all-cause mortality). The role of smoking, the strongest mediator in these analyses, did not change when using baseline or repeat assessments (from 32% to 35% for all-cause mortality). CONCLUSION In a civil service population in London, England, there was an association between socioeconomic position and mortality that was substantially accounted for by adjustment for health behaviors, particularly when the behaviors were assessed repeatedly.

Social inequality in coronary risk: central obesity and the metabolic syndrome. Evidence from the Whitehall ii study

SummaryThis report describes the social distribution of central obesity and the metabolic syndrome at the Whitehall II study phase 3 examination, and assesses the contribution of health related behaviours to their distribution. Cross-sectional analyses were conducted utilising data collected in 1991–1993 from 4978 men and 2035 women aged 39–63 years who completed an oral glucose tolerance test. There was an inverse social gradient in prevalence of the metabolic syndrome. The odds ratio (95 % confidence interval) for having the metabolic syndrome comparing lowest with highest employment grade was: men 2.2 (1.6–2.9), women 2.8 (1.6–4.8). Odds ratios for occupying the top quintile of the following variables, comparing lowest with highest grade, were, for waist-hip ratio: men 2.2 (1.8-2.8), women 1.6 (1.1-2.4); post-load glucose: men 1.4 (1.1-1.8), women 1.8 (1.2-2.6); triglycerides: men 1.6 (1.2-2.0), women 2.2 (1.5-3.3); fibrinogen: men 1.7 (1.4-2.3), women 1.9 (1.2-2.8). Current smoking status, alcohol consumption and exercise level made a small contribution (men 11%, women 9%) to the inverse association between socioeconomic status and metabolic syndrome prevalence. In conclusion, central obesity, components of the metabolic syndrome and plasma fibrinogen are strongly and inversely associated with socioeconomic status. Our findings suggest the metabolic syndrome may contribute to the biological explanation of social inequalities in coronary risk. Health related behaviours appear to account for little of the social patterning of metabolic syndrome prevalence.

Sickness absence as a global measure of health: evidence from mortality in the Whitehall II prospective cohort study

Abstract Objective To examine the association between sickness absence and mortality compared with associations between established health indicators and mortality. Design Prospective cohort study. Medical examination and questionnaire survey conducted in 1985-8; sickness absence records covered the period 1985-98. Setting 20 civil service departments in London. Participants 6895 male and 3413 female civil servants aged 35-55 years. Main outcome measure All cause mortality until the end of 1999. Results After adjustment for age and grade, men and women who had more than five medically certified absences (spells > 7 days) per 10 years had a mortality 4.8 (95% confidence interval 3.3 to 6.9) and 2.7 (1.5 to 4.9) times greater than those with no such absence. Poor self rated health, presence of longstanding illness, and a measure of common clinical conditions comprising diabetes, diagnosed heart disease, abnormalities on electrocardiogram, hypertension, and respiratory illness were all associated with mortality—relative rates between 1.3 and 1.9. In a multivariate model including all the above health indicators and additional health risk factors, medically certified sickness absence remained a significant predictor of mortality. No linear association existed between self certified absence (spells 1-7 days) and mortality, but the findings suggest that a small amount of self certified absence is protective. Conclusion Evidence linking sickness absence to mortality indicates that routinely collected sickness absence data could be used as a global measure of health differentials between employees. However, such approaches should focus on medically certified (or long term) absences rather than self certified absences.

Do socioeconomic differences in mortality persist after retirement? 25 Year follow up of civil servants from the first Whitehall study

Abstract Objective: To assess the risk of death associated with work based and non-work based measures of socioeconomic status before and after retirement age. Design: Follow up study of mortality in relation to employment grade and car ownership over 25 years. Setting: The first Whitehall study. Subjects: 18 133 male civil servants aged 40–69 years who attended a screening examination between 1967 and 1970. Main outcome measure: Death. Results: Grade of employment was a strong predictor of mortality before retirement. For men dying at ages 40–64 the lowest employment grade had 3.12 times the mortality of the highest grade (95% confidence interval 2.4 to 4.1). After retirement the ability of grade to predict mortality declined (rate ratio 1.86; 1.6 to 2.2). A non-work based measure of socioeconomic status (car ownership) predicted mortality less well than employment grade before retirement but its ability to predict mortality declined less after retirement. Using a relative index of inequality that was sensitive to the distribution among socioeconomic groups showed employment grade and car ownership to have independent associations with mortality that were of equal magnitude after retirement. The absolute difference in death rates between the lowest and highest employment grades increased with age from 12.9 per 1000 person years at ages 40–64 to 38.3 per 1000 at ages 70–89. Conclusions: Socioeconomic differences in mortality persist beyond retirement age and in magnitude increase with age. Social differentials in mortality based on an occupational status measure seem to decrease to a greater degree after retirement than those based on a non-work measure. This suggests that alongside other socioeconomic factors work itself may play an important part in generating social inequalities in health in men of working age. Key messages Relative differences in mortality between low and high employment grades are less after retirement, suggesting the importance of work in generating inequalities in health A non-work based measure of socioeconomic status (after adjustment for employment grade) continues to predict relative differences in mortality after retirement Absolute differences in mortality between less and more advantaged groups increase at older ages

Explaining socioeconomic differences in sickness absence: the Whitehall II Study.

OBJECTIVE--To describe and explain the socioeconomic gradient in sickness absence. DESIGN--Analysis of questionnaire and sickness absence data collected from the first phase of the Whitehall II study. Grade of employment was used as a measure of socioeconomic status. SETTING--20 civil service departments in London. SUBJECTS--6900 male and 3414 female civil servants aged 35-55 years. MAIN OUTCOME MEASURES--Rates of short spells (< or = 7 days) and long spells (> 7 days) of sickness absence. RESULTS--A strong inverse relation between grade of employment and sickness absence was evident. Men in the lowest grade had rates of short and long spells of absence 6.1 (95% confidence interval 5.3 to 6.9) and 6.1 (4.8 to 7.9) times higher than those in the highest grade. For women the corresponding rate ratios were 3.0 (2.3 to 3.9) and 4.2 (2.5 to 6.8) respectively. Several risk factors were identified, including health related behaviours (smoking and frequent alcohol consumption), work characteristics (low levels of control, variety and use of skills, work pace, and support at work), low levels of job satisfaction, and adverse social circumstances outside work (financial difficulties and negative support). These risk factors accounted for about one third of the grade differences in sickness absence. CONCLUSION--Large grade differences in sickness absence parallel socioeconomic differences in morbidity and mortality found in other studies. Identified risk factors accounted for a small proportion of the grade differences in sickness absence. More accurate measurement of the risk factors may explain some of the remaining differences in sickness absence but other factors, as yet unrecognised, are likely to be important.

Gender-specific associations of short sleep duration with prevalent and incident hypertension: the Whitehall II Study.

Sleep deprivation (≤5 hour per night) was associated with a higher risk of hypertension in middle-aged American adults but not among older individuals. However, the outcome was based on self-reported diagnosis of incident hypertension, and no gender-specific analyses were included. We examined cross-sectional and prospective associations of sleep duration with prevalent and incident hypertension in a cohort of 10 308 British civil servants aged 35 to 55 years at baseline (phase 1: 1985–1988). Data were gathered from phase 5 (1997–1999) and phase 7 (2003–2004). Sleep duration and other covariates were assessed at phase 5. At both examinations, hypertension was defined as blood pressure ≥140/90 mm Hg or regular use of antihypertensive medications. In cross-sectional analyses at phase 5 (n=5766), short duration of sleep (≤5 hour per night) was associated with higher risk of hypertension compared with the group sleeping 7 hours, among women (odds ratio: 2.01; 95% CI: 1.13 to 3.58), independent of confounders, with an inverse linear trend across decreasing hours of sleep (P=0.003). No association was detected in men. In prospective analyses (mean follow-up: 5 years), the cumulative incidence of hypertension was 20.0% (n=740) among 3691 normotensive individuals at phase 5. In women, short duration of sleep was associated with a higher risk of hypertension in a reduced model (age and employment) (6 hours per night: odds ratio: 1.56 [95% CI: 1.07 to 2.27]; ≤5 hour per night: odds ratio: 1.94 [95% CI: 1.08 to 3.50] versus 7 hours). The associations were attenuated after accounting for cardiovascular risk factors and psychiatric comorbidities (odds ratio: 1.42 [95% CI: 0.94 to 2.16]; odds ratio: 1.31 [95% CI: 0.65 to 2.63], respectively). Sleep deprivation may produce detrimental cardiovascular effects among women.

Health effects of anticipation of job change and non-employment : longitudinal data from the Whitehall II study

Abstract Objective : To assess the effect of anticipating job change or non-employment on self reported health status in a group of middle aged male and female white collar civil servants. Design : Longitudinal cohort study (Whitehall II study). Questionnaire data on self reported health status and health behaviour were obtained at initial screening and four years later, during the period when employees of the department facing privatisation were anticipating job change or job loss. Setting : London based office staff in 20 civil service departments. Subjects : 666 members of one department threatened with early privatisation were compared with members of the 19 other departments. Main outcome measures : Self reported health status measures and health related behaviours, before and during anticipation of privatisation. Results : In comparison to the remainder of the cohort, the profile of health related behaviours of cohort members who faced privatisation was more favourable, both before and during anticipation of privatisation. There were no significant differences in the changes in health behaviours between cohort members moving into a period of job insecurity and the remainder of the cohort. Self reported health status, however, tended to deteriorate among employees anticipating privatisation when compared with that of the rest of the cohort. Conclusions : The application of a longitudinal design, allowing the same individuals to be followed from job security into anticipation, provides more robust evidence than has previously been available that anticipation of job loss affects health even before employment status has changed.