This post is part of The Pump Handle's new “Public Health Classics” series exploring some of the classic studies and reports that have shaped the field of public health. View the first post of the series here, and check back at the "Public Health Classics" category for more in the future.
By Sara Gorman
The current state of public health research is increasingly aware of the effects of various kinds of inequality on health. Especially in the U.S. and other developed countries, the burden of chronic, non-communicable diseases is especially high among low-income individuals. Public health campaigns have thus developed initiatives to bring better health education to low-income communities and to encourage healthier eating, more exercise, and decreased use of tobacco and drugs.
What’s not always recognized is that the rationale behind many of these initiatives stems from the findings of a series of landmark studies among civil servants in England: the Whitehall Studies. Whitehall I began in 1967, at a time when awareness of the relationship between social inequality, work stress, and poor health was not necessarily keen. The Whitehall Studies thus set out to investigate the complex relationships among income, work status, psychosocial support, health behaviors, and resulting morbidity and mortality.
Whitehall I, published in Journal of Epidemiology and Community Health in 1978, followed British civil servants over ten years from 1967-1977 and ultimately showed an inverse association between employment grade and mortality from a variety of illnesses. After ten years of follow-up, those in the highest employment grade had one-third the mortality rate of those in the lowest grade.
The results of Whitehall I demanded some attempt at explanation. Whitehall II, a study of 10,314 British civil servants aged 35-55 published in The Lancet in 1991, represents this attempt. Importantly, while Whitehall I studied only male civil servants, Whitehall II also included women. Particularly important to Whitehall II is the effect of psychosocial factors, such as stress and social support, on disease outcome.
Whitehall II, conducted between 1985 and 1988, collected data primarily via surveys and questionnaires. Questionnaires distributed to the 10,314 British civil servants from 20 civil servanice department included questions about: health status, including questions about past medical history; work characteristics such as job demands and decision-making capacity; social networks and support; health behaviors, including smoking and physical activity; and the Framingham type A score, measuring hostility and stressful life events. In addition to questionnaires, subjects’ blood pressure was measured and screening was provided for angina and ischemia.
Whitehall II confirmed some of the results of Whitehall I, especially the finding that the lower the job status, the higher the prevalence of ischemic heart disease. New, landmark findings revolved around gender differences and isolation as possible causes of this inverse relationship. In general, women had greater morbidity than men in all grades of employment. The higher the job status of the man, the more likely he was to be married or cohabitating, but the opposite was true for women. Obesity was more prevalent among those in lower status jobs, and the risk factor for increased morbidity and mortality that differed most among job categories was smoking.
Overall, individuals in lower grades of employment were more resigned about their health. Individuals in lower employment grades were more likely to believe that it was not possible to reduce the risk of a heart attack. They were also more likely to rate their health status as poor and to report two or more of eight stressful life events in the previous year. Self-perceived poor health status is known to be a predictor of mortality.
Perhaps most significantly, the Whitehall II study discovered a firm connection among psychosocial factors, perception about work status and environment, and poor health outcomes. People in lower status jobs reported less social support than those in higher status jobs. They also reported less control, less use of skills, and less variety at work, as well as a more demanding workload and more psychological stress at work. All of these factors are associated with risk of cardiovascular disease.
The Whitehall Studies helped public health researchers develop a nuanced perspective on the relationship between socioeconomic position and health. The findings of Whitehall II established that it is not only factors most obviously related to obtainment of healthcare, such as time to attend doctors’ appointments or money to pay for insurance, that seriously affect health outcomes. Rather, psychosocial and socioeconomic factors that may seem unrelated to the provision of healthcare may have a direct impact on risk of developing cardiovascular disease and other chronic illnesses. Whitehall II in particular calls for careful attention to all of the conditions of every socioeconomic category as possible predictors of health outcomes. In many ways, these crucial studies established the interconnectedness of socioeconomic position, psychosocial factors, and health, a concept that is now at the very center of public health.
Sara Gorman is a PhD candidate at Harvard University. She has written extensively about HIV, TB, and women's and children's health for a variety of public health organizations, including Save a Mother and Boston Center for Refugee Health and Human Rights. She most recently worked in the policy division at the HIV Law Project.
This is a great choice of a classic study! And it's also a reminder that having a national health system makes it easier for health researchers. (Of course, this is secondary to the primary benefit of making sure everyone can get healthcare.) When following a US cohort, researchers need to think about controlling for insurance status and insurance plans.
That's a great point -- thank you!
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