Factors in coronary artery disease: cigarette smoking and exercise.

A study was made of certain information from studies of the State Department of Public Health which bear upon the hypotheses that cigarette-smoking and physical exercise are factors in coronary artery disease. The data supported an association of the disease with cigarette smoking, but not with exercise. An incidental finding was a strong relationship between coronary heart disease and the beginning of the wearing of reading glasses or bifocals at an early age. In the present state of investigations aimed at determining the etiology of coronary artery disease it appears desirable to give serious consideration to multiple factors rather than seeking to find a single cause.