Sex differences in the relationship among alcohol, smoking, and infection in asymptomatic individuals.

Objective: We aimed to investigate the relationship of infection with alcohol and smoking.

Methods: We conducted a cross-sectional study among participants who underwent health check-ups for infection between January 2013 and March 2017. We subsequently investigated the relationship of infection with alcohol and smoking.

Results: A total of 7169 participants were enrolled in this study. The overall prevalence of infection was 55.2%. Participants with infection were more likely to be older than those without infection. For male participants with infection, multivariable logistic regression analysis indicated that both smoking (odds ratio (OR): 1.61; 95% confidence interval (CI): 1.41-1.83) and alcohol consumption (OR: 1.30; 95% CI: 1.10-1.52) were independently positively associated with infection. For female participants, multivariable logistic regression analysis indicated that both smoking (OR: 0.03; 95% CI: 0.02-0.07) and alcohol consumption (OR: 0.20; 95% CI: 0.12-0.33) were inversely significantly associated with infection after adjustment for age.

Conclusions: Smoking and alcohol consumption were risk factors for male participants but these were protective factors for female individuals with infection.