A Cross-Sectional Study of Suicidal Behaviors and Physical Activity Among 65,182 Middle School Students in Tennessee USA
Introduction. Suicide-related fatalities are the third leading cause of death among adolescents, resulting in approximately 4,600 deaths annually. According to findings from the 2005 National College Health Assessment, engagement in weekly physical activity (PA) reduced the risk of suicidal behaviors. Data from the 2010 middle school Youth Risk Behavior Survey (YRBS) administered by Tennessee Coordinated School Health this study investigates the cross-sectional relationships of PA with suicidal behaviors, while simultaneously considering explanatory variables such as personal characteristics, sedentary behaviors, drug use, extreme weight control behaviors (EWCB), body mass index (BMI) and weight misperception. Methods. This is a secondary analysis of data from the 2010 Tennessee Middle School YRBS conducted among 65,182 middle school students of which 60,715 students were included in the final analysis. Items assessed were PA, sports team engagement, PE class, sedentary behaviors, suicidal behaviors, drug use, EWCB, BMI, weight misperception and selected personal characteristics. A bivariate analysis was used to create simple descriptive statistics, including means, standard deviations and proportions. Overall, approximately 21.15% (N= 13,704) reported suicidal behaviors, specifically, 18.30% reported ever having thoughts of suicide, 11.13% had ever made a suicide plan and 7.02% had one or more suicide attempts in their lifetime. A logistic regression analysis was conducted to compare the odds of experiencing suicidal behaviors in adolescents who engaged in PA, sports teams, and PE class, with students who did not perform these activities. We used odds ratios (OR) to assess effect size (ES), rather than p-values to assess statistical significance due to the study’s large sample size. As general rules of thumb, there is a small effect size when ES=0.20 or OR = 1.44, 0.694, medium effect size when ES=0.50 or OR = 2.47, 0.405 and large effect size when ES=0.80 or OR = 4.25, 0.235. Results. Based on ES, age, race/ethnicity, gender, grade in school, sports team engagement, PE class attendance, sedentary behaviors, drug use and EWCB were associated with suicidal behaviors. Associations were strongest for drug/substance use and EWCB and suicidal behaviors, both with large ESs. Although weakened when controlling for other independent variables, the ES of race/ethnicity (other vs white non-Hispanic), gender, sports team engagement, drug/substance use and EWCB on suicidal behaviors were >0.20. The ES of age, PE class attendance, and sedentary behaviors were <0.20. Conclusion. Findings suggest that sports team engagement is associated with reduced risk for suicidal behaviors; whereas, no effects were found for PA or PE class attendance. Asking adolescents questions about sports team engagement may help screen for risk of suicidal behaviors.