Baseline smoking status and the long-term risk of death or nonfatal vascular event in people with stroke: a 10-year survival analysis

Abstract

BACKGROUND AND PURPOSE: Smoking may exacerbate the risk of death or further vascular events in those with stroke, but data are limited. METHODS: 1589 cases of first-ever and recurrent stroke were recruited between 1996 and 1999 from a defined geographical region in North East Melbourne. Both hospital and nonhospital cases were included. Over a 10-year period, all deaths, recurrent stroke events, and acute myocardial infarctions that were reported at follow-up interviews were validated using medical records. Cox proportional hazards regression was used to assess the association between baseline smoking status (never, ex, and current) and outcome (death, acute myocardial infarction, or recurrent stroke). RESULTS: Patients who were current smokers (Hazard Ratio [HR], 1.30; 95% Confidence Interval [CI], 1.06-1.60; P=0.012) at the time of their stroke had poorer outcome when compared with those who had never smoked. Among those who survived the first 28 days of stroke, current smokers (HR, 1.42; 95% CI, 1.13-1.78; P<0.003) and ex-smokers (HR, 1.18; 95% CI, 1.01-1.39; P=0.039) at baseline had poorer outcome than those who had never smoked. Current smokers also had a greater risk of recurrent events than past smokers (HR, 1.23; 95% CI, 1.00-1.50; P=0.050). CONCLUSIONS: Patients who smoked at the time of their stroke or had smoked before their stroke had greater risk of death or recurrent vascular events when compared with patients who were never smokers. There are benefits of smoking cessation, with ex-smokers appearing to have a lesser risk of recurrent vascular events than current smokers.