Epidemiology of occupation and coronary heart disease: research agenda.

Little is known about occupational risks for coronary heart disease. A few specific toxins encountered occupationally are known to affect the heart, most prominently carbon disulfide, nitroglycerin, and carbon monoxide. Of these, carbon monoxide is the most common occupational exposure; it is also a common environmental exposure due to vehicle exhaust. Environmental tobacco smoke, noise, heat, and cold are suspected occupational risk factors for cardiovascular disease. In addition, stress at work may increase heart disease, although little is known conclusively with this regard. Unemployment may also increase risk of heart disease. Shift work, which disrupts circadian rhythms, has also been linked to heart disease, although there again, the data are far from conclusive. Physical activity at work, either too much or too little, can also be a risk factor for heart disease. While in general, more physical activity results in less heart disease, heavy lifting (in occupational and nonoccupational settings) has been associated with increased risk of heart attack. Further epidemiologic research into all these areas is warranted.