Exposure to secondhand smoke (SHS) has proven to be a public health problem. The problem is even worse among vulnerable groups like non-smoking children and adolescents. There is limited information on SHS exposure among Nigerian adolescents; thus, this study aims to describe the predictors of exposure to SHS among nonsmoking, in-school adolescents in Ibadan, Nigeria.

A cross-sectional study was conducted among randomly-selected non-smoking in-school adolescents (n=825), from 18 secondary schools in Ibadan, Nigeria. Using the GYTS questionnaires, respondents’ exposure to SHS was determined in relation to location: inside home, outside home, both inside and outside home, and either inside or outside home. Data were analyzed using descriptive statistics, bivariate analysis, and logistic regression model (α=0.05).

Participants’ mean age was 14 (SD=1.72) years, and they belonged to high, middle and low social class in the following respective proportions: 49.5%, 30.3% and 20.1%. The prevalence of exposure to SHS were: inside home (6.1%), outside home (31.5%), both inside and outside home (5.1%), and either inside or outside home (32.5%). The majority (56.2%) perceived that most of their peers smoke. Having a smoking friend (AOR=2.62; 95% CI: 1.58–4.37) and smoking family (AOR=2.08; 95% CI: 1.32–3.28), going on tobacco errands (AOR=3.32; 95% CI: 1.79–6.17), believing their peers smoke (AOR=1.48; 95% CI: 1.07–2.05) and belonging to a low social class (AOR=1.66; 95% CI: 1.05–2.62) were identified as predictors of exposure to SHS either inside or outside home.

One in every three adolescents was exposed to tobacco smoke either inside or outside home, and exposure to SHS outside home was higher than inside home. The high prevalence of secondhand tobacco smoking among in-school adolescents in Ibadan suggests that the smoke-free policy in Nigeria needs to be strengthened. Besides a comprehensive smoke-free environment, other tobacco-control interventions should extend to non-smoking adolescents, especially those having the predictors of SHS exposure found in this study.

We acknowledge the contributions of C.A. Ojeh, S.T. Akinrodoye, Y.D. Olatunji, O.I. Oni, C.S. Eneh, T.I. Gbademu, Q.A. Adeyemo, B.O. Animashaun and O.S. Jideofor.
The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none was reported.
There was no source of funding for this research.
OFF conceived the idea for the study, contributed to its design and in the analysis and interpretation of the data, and in drafting the manuscript. MEO contributed to the conception of the study and its design, and the acquisition of data. Both authors reviewed, edited and approved the final manuscript.
Not commissioned; externally peer reviewed.
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