The Relation Between Cigarette Smoking and Development of Sepsis: A 10-Year Follow-Up Study of Four Million Adults from the National Health Screening Program

Sepsis remains a growing global health concern with soaring mortality and no direct anti-sepsis drug. Although smoking has distinct deleterious effects on chronic inflammatory illnesses and can impair immune function, a comprehensive analysis of the connection between sepsis and smoking is lacking.

This large-scale longitudinal cohort study retrospectively assessed adults aged ≥ 20 years who underwent national health checkups under the Korean National Health Insurance Service between January and December 2009 (N = 4,234,415) and were followed up for 10 years. Sepsis was identified based on the International Classification of Diseases, 10th Revision codes, and smoking status, including accumulated amount, was collected through a self-administered questionnaire. The Cox proportional hazard regression model was used, adjusting for age, sex, household income, body mass index, drinking, exercise, diabetes, hypertension, dyslipidemia, and chronic renal disease.

After excluding cases with sepsis occurring before follow-up or after ≤ 1 year of follow-up, 3,881,958 participants, including non-smokers (N = 2,342,841), former smokers (N = 539,850), and active smokers (N = 999,267), were included. Compared to non-smokers, all active smokers (adjust hazard ratio: 1.41, 95% confidence interval 1.38–1.44) and former smokers (1.10, 1.07–1.14) with ≥ 20 pack-years exhibited a significantly higher risk of sepsis (p < 0.001). Smoking of ≥ 30 pack-years in former and active smokers groups significantly increased sepsis incidence (adjust hazard ratio [95% confidence interval] 1.34 [1.31–1.38], p < 0.001).

Smoking is closely associated with the incidence of sepsis. Smoking cessation may help in the primary prevention of sepsis.