Association of metabolic syndrome with smoking and alcohol intake in Japanese men

There have been conflicting findings on whether metabolic syndrome (MetS) is associated with smoking and alcohol intake. This study investigated the association of MetS with smoking and alcohol intake. MetS was defined according to the International Diabetes Federation criteria, and smoking and alcohol intake were evaluated for 1,215 Japanese male workers using a questionnaire. The association of MetS with smoking and alcohol intake was assessed using logistic regression after adjusting for potential confounders. Proportional analyses for the prevalence of MetS among smoking and alcohol intake were performed as well. Among the subjects, 148 (12%) were diagnosed with MetS, 485 (40%) were smokers, and 954 (79%) were regular alcohol users. The prevalence of MetS was the highest (19%) in smokers who did not drink, followed by smokers who also drank (13%), nonsmokers who drank (12%), and those who neither smoked nor drank (7%). Smoking itself was positively related to MetS (odds ratio [OR] = 1.4; 95% CI = 1.1-2.1) and MetS components, including larger waist circumference (OR = 1.5; 95% CI = 1.2-1.9), elevated triglyceride (OR = 1.9; 95% CI = 1.4-2.4), and reduced high-density lipoprotein cholesterol (OR = 1.7; 95% CI = 1.1-2.7). Alcohol intake was not significantly related to MetS; it was positively correlated only to higher fasting plasma glucose (OR = 1.7; 95% CI = 1.1-2.6). These results suggest that cigarette smoking is an independent risk factor for MetS, but the risk does not seem to be exaggerated by alcohol intake.