Weight change after smoking cessation and incident metabolic syndrome in middle-aged Korean men: an observational study

We aimed to examine the effect of weight change attributable to cessation of cigarette smoking on newly diagnosed metabolic syndrome (MetS). We prospectively followed 5,809 men aged between 40 to 69 years without MetS at baseline in the Health Examinees-Gem (HEXA-G) study up to 4 years. The participants were grouped into continual smokers, quitters with weight gain, quitters without weight change, quitters with weight loss, and never smokers. We constructed multivariable logistic regression models adjusted for sociodemographic factors, health status, and health conditions to estimate the odds of newly diagnosed MetS. During the follow-up, there were 609 cases of newly diagnosed MetS in 5,809 men of the HEXA-G study. After adjustment for potential confounders, the odd ratios (OR) and 95% confidence intervals (95% CI) for MetS were 1.90 (95% CI: 1.43–2.52) in quitters with weight gain, 0.77 (95% CI: 0.60–1.00) in quitters without weight change, and 0.40 (95% CI: 0.28–0.57) in quitters with weight loss compared with continual smokers. Never smokers also had lower odds of MetS (OR = 0.54; 95% CI: 0.42–0.71) compared to continual smokers. Weight management program following smoking cessation may be necessary in clinical practice to reduce worsening of cardiometabolic risk factors related to post-cessation weight gain.