Association Between Asthma, Obesity, Sleep Loss, Physical Activity and Substance Use Among the U.S. Adolescents: Findings from YRBS 2015

Objectives: Asthma is a genetic disease that requires an environmental trigger to manifest in predisposed individuals. This study aims to assess the prevalence of asthma among U.S. adolescents and possible environmental triggers to asthma. Methods: This is a secondary analysis of the Youth Risk Behavioral Survey 2015 (YRBS 2015). A total of 15,624 high school students in the U.S. were included in this analysis. The YRBS was established by Center for disease control and prevention (CDC) in 1991 to monitor six priority health risk behaviors among youths and young adults. Data were collected via self-administered questionnaire which was validated by CDC through a two test reliability studies. The Data was analyzed using SAS v 9.4. Results: The overall prevalence of asthma was 23.08% with no significant difference between male (22.84%) and female (23.31%). Simple logistic regression analysis showed that the estimated odds of having asthma among individuals that initiated cigarette smoking before the age of 13 years was about 40% higher than those who did not (Odds Ratio (OR): 1.40, 95% CI: 1.22-1.62, p\u3c0.0001). The odds of having asthma was also significantly higher among individuals who used marijuana before the age of 13 years (OR: 1.25, 95% CI: 1.11-1.46, p\u3c0.001) than those who did not. Furthermore, the estimated odds of having asthma was 25% higher in individuals currently using marijuana (OR: 1.25, 95%CI: 1.14-1.37, p\u3c0.0001) than those who do not and 44% higher among obese individuals (OR: 1.44, 95%CI: 1.29-1.60, p\u3c0.0001) compared to non-obese individuals. Sleeping eight or more hours per day was protective against asthma (OR: 0.81, 95% CI: 0.74-0.88, P\u3c0.0001). After adjusting for age and other factors, multiple logistic regression showed that the odds of having asthma was approximately 26% higher among individuals who initiated cigarette smoking before the age of 13 years (adjusted OR (aOR): 1.26, 95% CI: 1.01- 1.57, P=0.037) than those who did not. Moreover, the odds of having asthma was 18% higher among those who initiated alcohol drinking before the age of 13 years (aOR: 1.18, 95%CI: 1.04-1.35, P=0.014), compared to those who did not. There was no association found between asthma and physical activity, the use of marijuana after adjusting for age and other potential risk factors. Conclusion: While sleeping more than eight hours per day was protective against asthma, early initiation of cigarette smoking, marijuana, and alcohol drinking was positively associated with asthma. Encouraging children to sleep minimum of eight hours per day will potentially decrease asthma prevalence