Publications
Tobacco use and risk of acute stroke in 32 countries in the INTERSTROKE study: a case-control study
Xingyu Wang, Martin J O'Donnell, Allan Sniderman, Graeme J Hankey, Sumathy Rangarajan, Purnima Rao-Melacini, John Ferguson, Denis Xavier, Salim Yusuf Introduction
Tobacco use is the second leading cause of early death and disability worldwide and an avoidable cause of cardiovascular diseases.1 It is estimated that 29.6% of male and 5.3% of female are daily smokers worldwide.2 In 2016, there were 5.5 million deaths and 116.4 million disability adjusted life years lost (DALYs) due to stroke, accounting for 11.5% of global deaths.1 Despite a recent decline in the global prevalence of smoking overall, some countries are experiencing an increase among both male and female.3
Smoking is an established risk factor for stroke.4,5 Smoking is also a major risk factor for the global burden of stroke, ranking 5th overall amongst all stroke risk factors for males and females combined.5 However, the ranking of smoking risk varies between 4th and 10th among different regions and countries.1 In the INTERSTROKE study, we have previously reported a global population attributable risk (PAR) of stroke of 12.4% associated with current smoking, with a higher risk for ischemic stroke than intracerebral hemorrhage (ICH).6 Environmental tobacco smoke (ETS) exposure, also refer as secondhand tobacco smoke, is a debated risk factor for stroke, although prospective and cross-sectional studies have shown that overall exposure and high exposure to ETS increased the risk for stroke.7–10 Some reports suggested that the risk of stroke due to tobacco use begins to decrease soon after quitting.11
INTERSTROKE is the largest international study to report on the association of tobacco exposure with stroke incidence. In the current analyses, we extended our report to the association of stroke with different types of tobacco exposure, including non-smoked tobacco (e.g., chewed and pipes) and ETS (weekly hours of exposure) in different regions of the world and by country income levels, and within different pathological subtypes of stroke and etiological subtypes of ischemic stroke by TOAST classification,12 and may provide key insights into new opportunities for more effective smoking cessation interventions nationally and internationally.
