Mortality from heart disease in coal miners.

A study of 3,726 Appalachian coal miners was undertaken to determine the standard mortality ratio (SMR) for heart disease and to ascertain the effect of smoking, excess weight, and the level of physical activity on deaths due to this cause, SMR's were calculated for all forms of heart disease and also separately for ischemic heart disease. For heart disease as a whole, SMR's of 73 for working and 104 for nonworking miners were obtained. It was found in both working and nonworking miners that obese smokers had the greatest risk of dying of heart disease (SMR's of 142 and 144, respectively). In the nonsupervisory underground work categories of face, transportation, and maintenance, an increase of SMR was observed, with face having the lowest and maintenance workers having the highest SMR. Use of all men from seven Appalachian states vs all US men as a standard population tended to slightly reduce the calculated SMR's.