Development of new coronary atherosclerotic lesions during a 4-year multifactor risk reduction program: the Stanford Coronary Risk Intervention Project (SCRIP)

Abstract

Objectives: This study attempted to determine whether an intensive multifactor risk reduction program conducted over 4 years would reduce the rate of development of new coronary artery lesions.

Background: Recent angiographic trials have generally demonstrated that normalization of plasma lipoprotein profiles reduces the rate of progression of established coronary lesions, but limited data exist on how these treatments influence the development of new lesions.

Methods: Three hundred men and women with coronary artery disease were randomized to multifactor risk reduction or usual care. Highly significant improvements in risk factors were achieved by the risk reduction group compared with minimal changes by the usual care group. Quantitative coronary angiography was performed on entry and after 4 years under identical conditions. A decrement in the minimal diameter of visually normal segments > 0.2 mm was considered to indicate new lesion formation.

Results: A total of 1,605 segments, representing 257 patients, were considered normal at baseline, with 804 and 801 disease-free segments in the usual care and risk reduction groups, respectively. Ninety-nine segments (6.1%) were identified by follow-up quantitative angiography and two angiographic observers as having new lesion formation (usual care 7.6%, risk reduction 4.7%, p = 0.05). New lesion formation was observed in 41 (31%) of 131 patients in the usual care group and in 29 (23%) of 126 patients in the risk reduction group (p = 0.16), with a mean number of new lesions/patient of 0.47 in the usual care group and 0.30 in the risk reduction group (p = 0.06). Multiple regression analysis identified on-study dietary fat intake as the best correlate with new lesion formation.

Conclusions: These data indicate that intensive multifactor risk reduction tends to diminish the frequency of new coronary lesion formation.