OBJECTIVE

Smoking is a leading preventable cause of disease and death worldwide, with severe implications for individuals with chronic kidney disease (CKD). Although smoking at a younger age is linked to higher mortality risk, the specific effects of early smoking on all-cause and cardio-cerebrovascular diseases (CCVDs)-specific mortality in CKD patients are not well established. This study aims to examine the association between early smoking, smoking intensity, and mortality in patients with CKD.

METHODS

This nationwide, population-based cohort study utilized data from the National Health Insurance Database (NHID) of South Korea, provided by the National Health Insurance Service (NHIS). The study included 549,739 adults with CKD who underwent national health examinations in 2009. The primary exposures were the age at smoking initiation and smoking intensity, measured in pack-years. Cox proportional hazards models were used to analyze the association between these exposures and mortality outcomes.

RESULTS

Earlier smoking initiation and higher smoking intensity were significantly associated with increased risks of all-cause and CCVDs-specific mortality among patients with CKD. Specifically, individuals who began smoking at a younger age and those with higher pack-years had a notably higher risk of mortality.

CONCLUSIONS

The findings suggest that early smoking and smoking intensity are associated with higher mortality risks in CKD patients. Preventive measures targeting early smoking initiation may help improve the long-term outcomes in high-risk population.