Abstract
The aim of this study was to examine the effects of smoking on changes in cardiovascular disease risk factors between childhood and young adulthood. Blood pressure, serum lipoproteins and body mass index were measured in 2258 individuals ; as children in 4 baseline surveys (1974-1977) and as young adults in 3 follow-up surveys (1985-1996), in the biracial community of Bogalusa, Louisiana. Smoking variables were defined as categories based on (1) present smoking status, (2) cumulative smoking volume (pack-years ever smoked), and (3) years since quitting smoking. We found that in heavier smokers there was a significantly greater increase in low-density lipoprotein cholesterol and serum triglycerides, and a decrease in high-density lipoprotein cholesterol. These changes showed appropriate dose-response gradients. The length of time individuals remained smoke-free was related to significantly smaller increases in blood pressure and serum triglycerides (in both sexes), and to an increase in body mass index in males only. These findings support the use of pack-years as an appropriate indicator for evaluation of changes in risk factor variables. The results suggest that even in young adulthood, smoking causes adverse changes in the risk factors for cardiovascular disease, and that quitting smoking earlier brings about beneficial changes.
