Longitudinal effect of smoking cessation on physical and laboratory findings.

Background Detailed information on the expected physiologic changes after smoking cessation is practically useful to encourage people to stop smoking. Furthermore, weight increase after cessation may affect such physiologic changes. Purpose This article aims to evaluate the effect of smoking cessation on annual changes in body weight, blood pressure, and blood biochemistry. Methods This study analyzed the results of annual health examinations from 1991 to 2005 in male Japanese workers in 2009. Subjects classified as stopping smoking ( n =445) responded initially as smokers in a self-administered questionnaire (baseline year) and then answered consistently as nonsmokers for 3 subsequent years. Of the 2672 smokers identified in the study, 2403 subjects who had data available for at least 4 successive years were selected as controls. The time course of physiologic and laboratory data was analyzed using a linear mixed model. Results Data adjusted for age, type of job schedule, drinking and physical activity showed that subjects who stopped smoking had significantly greater increases in weight, BMI, systolic and diastolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, and uric acid and a greater decrease in hemoglobin in the 3 years following smoking cessation than continuing smokers. Additional adjustment for change in BMI from baseline negated the significant deterioration in systolic and diastolic blood pressure and total cholesterol that occurred following smoking cessation. Conclusions Increase in body weight, blood pressure, and blood biochemistry can continue for at least 3 years after smoking cessation. This study also indicated that these increases were related to the weight increase that occurred after smoking cessation.