Occupational coronary heart disease among bridge and tunnel officers

Traffic-control officers employed in New York City tunnels prior to 1981 have been at increased risk of mortality from coronary heart disease. In this study, the authors assessed current coronary heart disease prevalence and evaluated associations between coronary heart disease and occupational factors among New York City bridge and tunnel officers. A clinical cardiovascular disease surveillance and cross-sectional occupational epidemiologic study was conducted. The authors used comprehensive evaluations to identify current and prior incidences of coronary heart disease. Occupational risk factors evaluated included job strain, current and historic exposure to carbon monoxide, and occupational physical inactivity. Current carbon monoxide exposure was assessed via workshift changes in carboxyhemoglobin. Coronary heart disease occurred in 29 (5.5%) of the 526 bridge and tunnel officers examined. Risk of coronary heart disease was associated positively with total years each bridge and tunnel officer work had worked in that capacity (odds ratio = 1.64 for each decade of employment, adjusted for nonoccupational coronary heart disease risk factors). Carboxyhemoglobin levels were low in the subjects, and job strain and physical inactivity were very prevalent. Occupational factors contributed to the risk of coronary heart disease in New York City bridge and tunnel officers. The authors were unable to identify the specific factors that led to the increase in risk described.