Effect of smoking cessation on new-onset diabetes mellitus in dyslipidemic individuals: A population-based cohort study.

Abstract

Introduction: Smoking is a modifiable risk factor for diabetes mellitus, but the association between changes in smoking behavior and new-onset diabetes mellitus (NODM) in dyslipidemic patients remains unclear. This study aimed to examine how changes in smoking habits affect NODM risk among individuals with dyslipidemia.

Methods: This retrospective cohort study used data from the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC). A total of 34282 patients diagnosed with dyslipidemia between 2012 and 2014 were followed until December 2019 (median follow-up: 5 years). Smoking behavior change was defined by transitions in smoking status and intensity across two health examinations. NODM was identified by fasting plasma glucose ≥126 mg/dL or ICD-10 codes E11-E14 with antidiabetic medication.

Results: During follow-up, 2479 participants (7.23%) developed NODM. Those with NODM had higher prevalence of obesity, abdominal obesity, hypertension, abnormal liver function, and family history of diabetes. Current smokers had increased NODM risk (hazard ratio, HR=1.36; 95% CI: 1.22-1.50) versus non-smokers. Heavy smokers had higher risk (HR=1.43; 95% CI: 1.24-1.60) than moderate smokers (HR=1.35; 95% CI: 1.16-1.60). Compared to continuous smokers, quitters had reduced risk (HR=0.79; 95% CI: 0.64-0.98), while reducers showed no significant risk reduction (HR=0.82; 95% CI: 0.63-1.08).

Conclusions: Among patients with dyslipidemia, smoking cessation was associated with a lower risk of NODM compared to continued smoking. These results suggest potential benefits of quitting smoking in reducing diabetes risk in this population.