Smoking Cessation Intervention (SCI) in Patients with Type 2 Diabetes Mellitus - a Cohort Study

Rehabilitation programs for patients diagnosed with Type 2 diabetes mellitus (T2DM) include smoking cessation to reduce development of complications and pre-mortality. This study aimed to compare successful smoking cessation after the intensive 6-week Gold Standard Program (GSP) among smokers with and without T2DM in Denmark. Additionally, we evaluated predictors of successful quitting. This register-based cohort study evaluated data from a total of 38,776 patients collected over a decade via the Danish STOPbase for Tobacco & Nicotine from 252 Stop-Units across Denmark. A further 1,373 (4%) did not consent to the 6-month follow-up or had died/immigrated and were not part of this study. In the Danish National Patient Registry, 1,400 patients were diagnosed with T2DM prior to participating in the GSP and the control group of 36,888 patients had no diagnosis of diabetes. In addition, 488 patients had other types of diabetes and were excluded. The follow-up rates were about two thirds in the T2DM and the control groups; 67.3 % (942/1,400) and 68.6% (25,312/36,888), respectively. After 6 months, the continuous abstinence rate was 25.3% and 24.9% (adjusted OR 1.09; 95% CI 0.94-1.26) for the T2DM and control groups, and the 14- day point prevalence was 29.4% and 29.2% (adjusted OR 1.08; 95% CI 0.93-1.25). Compliance, measured as meeting adherence, was the strongest predictor of successful quitting (adjusted OR 3.27; 95% CI: 3.07-3.49). In conclusion, after participation in the GSP for 6 months, there was no statistical difference in successful quitting between patients with and without T2DM; therefore, we rejected the hypothesis. Compliance was the utmost important predictor of successful smoking cessation.