A series of studies beginning in 1967 in the United Kingdom conducted by Sir Michael Marmot, known as the “Whitehall” studies, followed 17,530 men working as government employees and discovered dramatically different health outcomes over time based mostly on the employee’s type of job. Men in jobs classified as “higher grade,” such as administrators and executives, had significantly better health over time than men in “lower grade” positions, such as clerical workers and unskilled manual laborers. A careful analysis of these data showed that differences in health status were only partially associated with known risk factors. Moreover, when risk factors were controlled for, there were still large and statistically significant differences in health status attributed to the employee’s relative position in the work hierarchy. These differences persisted among the men followed for more than 20 years, and these strong effects of job status on health were later replicated among both male and female government workers.
Perhaps not unexpectedly, participants in the Whitehall study had markedly different risk factors identified at the start of the study across job grades. Compared with administrators and executives, men who were in the lowest job grade were approximately twice as likely to smoke cigarettes, were less likely to have active leisure activities, had more weight anomalies (very heavy or very thin), were significantly shorter in height, and had higher blood pressure. Only plasma cholesterol was higher for those in higher status job grades. What was surprising was that baseline differences in risk factors for health problems were not the best predictors of the incidence of serious health problems and death.
After following the government workers enrolled in the Whitehall study for 7.5 years, striking differences in the health of participants were found across employment grades. Interestingly, even when the baseline effects of age, blood pressure, cholesterol, smoking, and height were adjusted through statistical analysis, it still was found that compared with the most senior employees (administrators), there was a strong linear relationship between job grade and mortality from coronary heart disease, with twice the mortality for professional executives, three times more for clerical workers, and four times more for the lowest grade workers (Figure 5-1). Remarkably, more than 60% of these large differences in mortality from coronary heart disease were attributable to job grade differences, and only 40% of the effect could be explained by traditional risk factors.
Linear relationship between job grade and mortality. CHD, congestive heart disease. (Reproduced with permission from Marmot MG, Rose G, Shipley M, Hamilton PJ. Employment grade and coronary heart disease in British civil servants. J Epidemiol Community Health. 1978;32(4):244-249.)
This seminal study identified the profound effects of social factors, such as job status, in the production of health and ushered in an era of evolving research highlighting the compelling and complex ...