Decision latitude, psychologic demand, job strain, and coronary heart disease in the Western Electric Study.

The hypothesis that low decision latitude and high psychologic demand are associated with an increased risk of the incidence of and mortality from coronary heart disease was investigated in a 25-year follow-up study of 1,683 men aged 38-56 years who participated in the Chicago Western Electric Study (1957-1983). Scores for decision latitude and psychologic demand, which had been linked to the 1960 US Census occupation codes, were assigned to men in the Western Electric cohort based on job title at the initial examination (1957-1958). After adjustment for major coronary risk factors, the relative risk for 25-year coronary death was 0.76 (95% confidence interval (CI) 0.59-1.00) for a 20-point increase in the decision latitude score (approximate difference between tertiles) and was 0.78 (95% CI 0.48-1.26) for a 10-point increase in the psychologic demand score (approximate difference between three groups). For job strain (defined by low decision latitude and high psychologic demand), it was 1.40 (95% CI 0.92-2.14). Controlling for occupational class reduced the magnitude of the relative risks between job characteristics and coronary mortality. Analysis stratified by occupational class indicated that the effect of decision latitude was more pronounced for white-collar than for blue-collar workers. This study provided only limited evidence for associations between job characteristics and coronary heart disease mortality.