Background: Smoking is a known risk factor for ischemic stroke, while increased BMI has been associated with improved outcomes in patients with cardiovascular disease. We investigated the relationship between smoking, BMI, and outcomes in patients with non-hemorrhagic stroke.
Methods: Study cohort consisted of 610 consecutive patients treated for non-hemorrhagic stroke at a single academic medical center. Retrospective chart review was conducted. Long-term outcomes were ascertained through Social Security Death Index. The study was approved by the institutional IRB.
Results: The prevalence of smoking was 42%. There were more male smokers (48% vs. 35% females, p<0.001). The mean BMI was similar in smokers and non-smokers (29+/-12.7 vs. 28.8+/-14, p=0.842). Similarly, associations between smoking and hypertension, peripheral vascular disease, dyslipidemia, end-stage renal disease, and systemic evidence of atherosclerosis by TTE were not statistically significant. However, age of a smoker at the time of admission for non-hemorrhagic stroke was 5 years younger than in a non-smoker (60.7+/-15 vs. non-smokers 65.3+/-17.5, p<0.001).
The mean follow up length was 51.4+/-1.3 months in smokers and 48.6+/-1.0 months in non-smokers. Observed crude mortality of 22.2% in smokers and 24.3% in non-smokers (p=0.559) was not significantly different in patients with normal, or increased BMI. However, smokers with non-hemorrhagic stroke died at significantly younger age (64.8+/-14.6 vs. 69.2+/-17.1, p=0.001). Additionally, there were trends towards increased mortality in smokers with BMI <18.5 kg/m2 (10.2 vs. 5.3% in non-smokers, p=0.226), dyslipidemia (38% vs. 24% in non-smokers, p=0.054) and chronic renal disease (64% vs. 36% in non-smokers, p=0.889).
Conclusion: Smokers present with non-hemorrhagic stroke at a significantly younger age than non-smokers and die at much younger age during follow-up. While in our cohort smoking was not linked to other traditional risk factors for non-hemorrhagic stroke, it was associated with increased mortality in patients with decreased BMI, dyslipidemia, and with renal disease. “Protective” effect of increased BMI was not observed in smokers.