The Misleading 'Smoker's Paradox' in Young Stroke

Objective: Stroke in young adults is uncommon, and the etiologies and risk factors of stroke in young adults differ from those in the older populations. Smoker’s paradox is an unexpected favorable outcome, and age difference was used to explain the association between smoking and the favorable functional outcome. This study aimed to investigate the existence of this phenomenon in young stroke patients.Methods: We analyzed a total of 9,460 young stroke cases registered in the nationwide stroke registry system of Taiwan between 2006 and 2016. Smoking criteria included having a past or current history of smoking more than 1 cigarette per day for more than 6 months. After matching for sex and age, a Cox model was used to compare complications, mortality and outcomes between smokers and non-smokers.Results: Smoking was associated with older age, higher comorbidities, and higher alcohol consumption. Smoking patients with NIHSS scores of 11–15 had a worse functional outcome (adjusted OR, 0.81; 95% CI, 0.76–0.87), and smoking cessation would substantially reverse those effects.Conclusion: The smoker’s paradox definitely does not exist, and therefore we continue to strongly advocate the importance of smoking cessation.