Application of Competing Risks Model in Predicting Smoking Relapse Following Ischemic Stroke

Objective To determine factors associated with smoking relapse in men who survived from their first stroke. Methods Data were collected through face to face interviews with stroke patients in the hospital, and then repeated every three months via telephone over the period from 2010 to 2014. Kaplan-Meier method and competing risk model were adopted to estimate and predict smoking relapse rates. Results The Kaplan-Meier method estimated a higher relapse rate than the competing risk model. The four-year relapse rate was 43.1% after adjustment of competing risk. Exposure to environmental tobacco smoking outside of home and workplace (such as bars and restaurants) (P=0.01), single (P<0.01), and prior history of smoking at least 20 cigarettes per day (P=0.02) were significant predictors of smoking relapse. Conclusion When competing risks exist, competing risks model should be used in data analyses. Smoking interventions should give priorities to those without a spouse and those with a heavy smoking history. Smoking ban in public settings can reduce smoking relapse in stroke patients.