Coronary risk factor intervention: characteristics associated with change.

Predicting change in coronary heart disease (CHD) risk factors (cigarette smoking, hypertension, and cholesterol) was undertaken in participants randomized to the treatment group of the Harvard Center of the Multiple Risk Factor Intervention Trial. The predictor variables of interest were psychosocial characteristics, responses to the initial group sessions intervention strategy, and change in weight. The Harvard sample consists of 652 men identified at high risk of death from CHD. Fifty percent were randomized into an intervention group, and 50% were referred to their usual source of medical care. For the analyses, men were stratified by their baseline smoking status and whether they were taking medication for hypertension. The analyses revealed that there was no single model that explained changes in all three risk factors. For example, cigarette smokers were significantly more likely to stop smoking if they attended the group sessions (p less than or equal to .001). An internal locus of control predicted a lower blood pressure by the end of the first year independent of medication (p less than or equal to .05). If a participant entered the trial with serum cholesterol as the only risk factor of concern, attending the group sessions was associated with a significant decrease by the end of the first year (p less than or equal to .05).