Overweight Status and Suicidal Behaviors among Adolescents: Correlation or Causation?
- Presenter:
Chair: Glenn Blomquist; Discussant: Zhun Cao Tue June 6, 2006 8:00-9:30 Room 325
Suicide is the third leading cause of death for adolescents. The suicide rate for individuals 15-19 years of age in 2002, while having recently declined, still remains twice that in 1960. At the same time, the prevalence of being overweight has also steadily risen among adolescents. In 2002, 16.1 percent of adolescents ages 12-19 were overweight, compared to 4.6 percent in 1968. This study utilizes data from the Youth Risk Behavioral Surveillance System (1991-2003) and the National Comorbidity Survey (1991) to explore the causal relationship between overweight (and the perception of overweight) on suicide ideation and attempts. Studies have shown a high degree of correlation between overweight, depressive disorders, and suicidal behaviors. Overweight or the perception of overweight may have a causal impact on depressive disorders, may lead to or reinforce other problem behaviors, and in turn may trigger suicidal thoughts and attempts. On the other hand, adolescents may not be randomly selected into overweight and suicidal behaviors, in which case the unobserved heterogeneity may be driving the association. Propensity score matching and constrained bivariate probit methods are used to assess the degree to which the observed correlation between overweight status and suicidal behaviors is driven by systematic selection rather than true causality. If overweight status is found causally to raise the propensity of engaging in suicidal ideation and attempts, then risk of suicide should be added to the economic costs of obesity. Isolating causal risk factors for suicidal behaviors may also guide targeted interventions for identifying and assisting atrisk youths.