H3Africa PI: Mayowa Owolabi
Institution: University of Ibadan
Project Affiliation: SIREN
Background: Stroke is a leading cause of morbidity and mortality worldwide, but little is known about the significance of indirect exposure to tobacco smoke(secondhand smoke exposure –SHSE and non-cigarette tobacco use –NCTU) in stroke epidemiology among indigenous Africans. This study aimed to evaluate the association of SHSE and NCTU with first-ever stroke among indigenous Africans.
Methods: A total of 7,617 respondents who had never smoked were identified in the Stroke Investigation Research and Educational Network (SIREN) study. A stroke case was defined based on clinical presentation and confirmed with a cranial CT or MRI. At the same time, the main exposure variables, SHSE and NCTU were self-reported using validated instruments. Multivariable-adjusted logistic regression was applied to estimate the adjusted odds ratio (aOR) and 95% confidence interval (CI) for the independent associations of SHSE and NCTU with stroke at a two-sided p<0.05.
Results:Mean age of respondents was 59.23 ± 12.20 years with a male proponde race(65.9%). Overall, 19.5% and 0.5% of this sample reported SHSE and NCTU respectively. SHSE was associated with odds of stroke; aOR: 1.25 (95% CI: 1.04, 1.50); P= 0.017,whereas NCTU was associated with a2-fold risk of stroke (aOR: 2.08; 95% CI: 1.02,4.23).Further stratification by stroke types revealed similar trends independent of stroke subtype.
Conclusion: Indirect exposure to tobacco smoke was associated with an increased risk of stroke among indigenous Africans. Therefore, public health interventions targeted at impulsive or
involuntary tobacco exposure might be promising in reducing the already high burden of stroke among Africans.
Keywords: Stroke; Secondhand smoke; Non-cigarette tobacco; Indigenous Africans; SIREN