Jenny Head

Health inequalities among British civil servants: the Whitehall II study

The Whitehall study of British civil servants begun in 1967, showed a steep inverse association between social class, as assessed by grade of employment, and mortality from a wide range of diseases. Between 1985 and 1988 we investigated the degree and causes of the social gradient in morbidity in a new cohort of 10,314 civil servants (6900 men, 3414 women) aged 35-55 (the Whitehall II study). Participants were asked to answer a self-administered questionnaire and attend a screening examination. In the 20 years separating the two studies there has been no diminution in social class difference in morbidity: we found an inverse association between employment grade and prevalence of angina, electrocardiogram evidence of ischaemia, and symptoms of chronic bronchitis. Self-perceived health status and symptoms were worse in subjects in lower status jobs. There were clear employment-grade differences in health-risk behaviours including smoking, diet, and exercise, in economic circumstances, in possible effects of early-life environment as reflected by height, in social circumstances at work (eg, monotonous work characterised by low control and low satisfaction), and in social supports. Healthy behaviours should be encouraged across the whole of society; more attention should be paid to the social environments, job design, and the consequences of income inequality.

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.

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.

Work and psychiatric disorder in the Whitehall II Study.

It is important that the effects of work on mental health are investigated when work practices are changing rapidly and there is decreasing job security. This has been examined in the Whitehall II Study, a cohort study of 6895 male and 3413 female, London-based civil servants, aged 35-55 years at baseline in 1985. Work characteristics were measured by modified Karasek indices in a self-report questionnaire. Psychiatric disorder was measured by the 30-item General Health Questionnaire (GHQ). In longitudinal analyses in men and women, high work social support predicted lower GHQ scores, and high job demands predicted higher GHQ scores at follow-up. High work social support and high skill discretion were protective against taking short spells of psychiatric sickness absence. The protective effects of social support at work and the potential risk of job demands have implications for management, job design, training, and further research.

Explaining social class differences in depression and well-being

Abstract Work characteristics, including skill discretion and decision authority, explain most of the socioeconomic status gradient in well-being and depression in middle-aged British civil servants from the Whitehall II Study, London. Social support explained about one-third of the gradient, life events and material difficulties less than one-third. Socioeconomic status was measured by employment grade. Work characteristics were based on the Karasek model, social support was measured by the Close Persons Questionnaire, depression by the General Health Questionnaire and well-being by the Affect Balance Scale. Despite a small contribution from social selective factors measured by upward mobility, the psychosocial work environment explained most of the cross-sectional socioeconomic status gradient in well-being and depression.

A comparison of self-reported sickness absence with absences recorded in employers’ registers: evidence from the Whitehall II study

Aim: To compare self-reported sickness absence days in the last 12 months with recorded absences from the employers’ registers for the same period. Methods: Self-reported sickness absence data over the 12 months preceding baseline (1985–88) were compared with absence records from the employers’ registers over the same period for 2406 women and 5589 men, participants in the Whitehall II study of British civil servants. Associations with self-rated health, longstanding illness, minor psychiatric disorder, physical illness, and prevalent coronary heart disease at baseline were determined. Results: In general, women reported less sickness absence over the last year than was recorded in the employers’ registers, while men, with the exception of those in the lower employment grades, reported more. Agreement between self-reported and recorded absence days decreased as the total number of days increased. After adjustment for employment grade and the average number of recorded and self-reported absence days, the total number of self-reported absence days was within two days of the recorded number of days for 63% of women and 67% of men. Associations between annual self-reported sickness absence days and self-rated health, longstanding illness, minor psychiatric disorder, physical illness, and prevalent coronary heart disease were as strong as those for recorded absence days. Conclusion: These findings suggest that agreement between the annual number of self-reported and the annual number of recorded sickness absence days is relatively good in both sexes and that associations with health are equivalent for both measures.

Social inequalities in depressive symptoms and physical functioning in the Whitehall II study: exploring a common cause explanation

Study objective: This study investigated which risk factors might explain social inequalities in both depressive symptoms and physical functioning and whether a common set of risk factors might account for the association between depressive symptoms and physical functioning. Design: A longitudinal prospective occupational cohort study of female and male civil servants relating risk factors at baseline (phase 1: 1985–8) to employment grade gradients in depressive symptoms and physical functioning at follow up (phase 5: 1997–9). Analyses include the 7270 men and women who participated at phase 5. Setting: Whitehall II Study: 20 London based white collar civil service departments. Participants: Male and female civil servants, 35–55 years at baseline. Main results: Depressive symptoms were measured by a subscale of items from the 30 item General Health Questionnaire. Physical functioning was measured by a subscale of the SF-36. Employment grade was used as a measure of socioeconomic position as it reflects both income and status. The grade gradient in depressive symptoms was entirely explained by risk factors including work characteristics, material disadvantage, social supports, and health behaviours. These risk factors only partially explained the gradient in physical functioning. The correlation between depressive symptoms and physical functioning was reduced by adjustment for risk factors and baseline health status but not much of the association was explained by adjustment for risk factors. Among women, the association between depression and physical functioning was significantly stronger in the lower grades both before and after adjustment for risk factors and baseline health. For women, there was only a significant grade gradient in depressive symptoms among those reporting physical ill health. Conclusions: Some risk factors contribute jointly to the explanation of social inequalities in mental and physical health although their relative importance differs. Work is most important for inequalities in depressive symptoms in men, and work and material disadvantage are equally important in explaining inequalities in depressive symptoms in women while health behaviours are more important for explaining inequalities in physical functioning. These risk factors did not account for the association between mental health and physical health or the greater comorbidity seen in women of lower socioeconomic status. The risk of secondary psychological distress among those with physical ill health is greater in the low employment grades.

The psychosocial work environment and alcohol dependence: a prospective study

Aims: To examine whether a stressful psychosocial work environment predicts alcohol dependence. Methods: Alcohol dependence of participants in the Whitehall II occupational cohort of London based civil servants (1985–88) was measured in 1991–93 using the CAGE questionnaire. The psychosocial work environment was measured by self report questions on the job demand-support-control model and on the model of effort-reward imbalance. Potential mediators including physical illness and poor mental health (GHQ) were measured at follow up in 1989. Results: Effort-reward imbalance at work was associated with alcohol dependence in men after adjustment for employment grade and other baseline factors related to alcohol dependence. Although effort-reward imbalance predicted future longstanding illness, poor mental health and negative aspects of close relationships, the association between effort-reward imbalance and alcohol dependence in men was only partially mediated through these health and social support measures. In women, low decision latitude was related to alcohol dependence to some extent, but alcohol dependence among women was more prevalent in higher occupational grades. Men with high job demands or with low work social supports had a slightly reduced risk of alcohol dependence. No association was found between objectively assessed demands, job control, and alcohol dependence in either men or women. Conclusion: A stressful psychosocial work environment in terms of effort-reward imbalance was found to be a risk factor for alcohol dependence in men. In view of the public health importance of alcohol dependence in working populations these findings call for more emphasis on psychosocial factors in occupational health research and prevention.

Injustice at work and incidence of psychiatric morbidity : the Whitehall II study

Background: Previous studies of organisational justice and mental health have mostly examined women and have not examined the effect of change in justice. Aim: To examine effects of change in the treatment of employees by supervisors (the relational component of organisational justice) on minor psychiatric morbidity, using a cohort with a large proportion of men. Methods: Data are from the Whitehall II study, a prospective cohort of 10 308 white-collar British civil servants (3143 women and 6895 men, aged 35–55 at baseline) (Phase 1, 1985–88). Employment grade, relational justice, job demands, job control, social support at work, effort–reward imbalance, physical illness, and psychiatric morbidity were measured at baseline. Relational justice was assessed again at Phase 2 (1989–90). The outcome was cases of psychiatric morbidity by Phases 2 and 3 (1991–93) among participants case-free at baseline. Results: In analyses adjusted for age, grade, and baseline physical illness, women and men exposed to low relational justice at Phase 1 were at higher risk of psychiatric morbidity by Phases 2 and 3. Adjustment for other psychosocial work characteristics, particularly social support and effort–reward imbalance, partially attenuated these associations. A favourable change in justice between Phase 1 and Phase 2 reduced the immediate risk (Phase 2) of psychiatric morbidity, while an adverse change increased the immediate and longer term risk (Phase 3). Conclusion: This study shows that unfair treatment by supervisors increases risk of poor mental health. It appears that the employers’ duty to ensure that employees are treated fairly at work also has benefits for health.

Body mass, weight control behaviours, weight perception and emotional well being in a multiethnic sample of early adolescents

Objective:To investigate weight perception, dieting and emotional well being across the range of body mass index (BMI) in a population-based multiethnic sample of early adolescents.Design:Cross-sectional population-based survey.Subjects:In total, 2789 adolescents 11–14 years of age from three highly deprived regional authorities in East London, in 2001.Measurements:Data were collected by student-completed questionnaire on weight perception, dieting history, mental and physical health, health behaviours, social capital and sociodemographic factors. Height and weight were measured by trained researchers. Overweight was defined as BMI ⩾85th centile and obesity as BMI ⩾98th centile. Underweight was defined as BMI⩽15th centile.Results:In all, 73% were from ethnic groups other than white British. Valid BMI were available for 2522 subjects (90.4%) of whom 14% were obese. Only 20% of overweight boys and 51% of overweight girls assessed their weight accurately. Accuracy of weight perception did not vary between ethnic groups. In all, 42% of girls and 26% of boys reported current dieting to lose weight. Compared with white British teenagers, a history of dieting was more common among Bangladeshi, Indian and mixed ethnicity boys and less likely among Pakistani girls. Self-esteem was not associated with BMI in girls but was significantly lower in obese boys than those of normal weight (P=0.02). Within ethnic subgroups, self-esteem was significantly lower in overweight white British boys (P=0.03) and obese Bangladeshi boys (P=0.01) and Bangladeshi girls (P=0.04), but significantly higher in obese black African girls (P=0.01) than those of normal weight. Obese young people had a higher prevalence of psychological distress (P=0.04), except among Bangladeshi teenagers, where overweight and obese young people had less psychological distress than those of normal weight (P=0.02). Birth outside the UK was associated with reduced risk of obesity in girls (P=0.02) but not with history of dieting, weight perception or psychological factors in either gender.Conclusion:High levels of current dieting for weight control and inaccurate perception of body mass are common across all ethnic groups. However, dieting history and the associations of obesity with self-esteem and psychological distress vary between ethnic groups. Interventions to prevent or treat obesity in black or minority ethnicity groups must consider cultural differences in the relationship between body mass, self-esteem and psychological distress.