Abstract
Overwhelming evidence suggests that physical activity among youth can prevent mental illness; however, few studies have explored its effects on mental healthcare utilization. This study aimed to examine the longitudinal associations between physical activity among Canadian adolescents and young adults (AYAs; 12-24 years) and incidence of psychiatric hospitalizations. Physical activity was measured in the 2001-2014 Canadian Community Health Survey (CCHS) and was linked to the Discharge Abstract Database. Negative binomial regression analyses were performed on each CCHS cycle to obtain incidence rate ratios (IRRs) for psychiatric hospitalizations by level of physical activity, which were subsequently meta-analyzed to obtain pooled estimates. In total, 96,100 participants were recruited across eleven cycles. Adolescents were more physically active (52%) compared to young adults (39%). The most common cause of hospitalization was mood or anxiety disorders (38%). Fully adjusted models found that moderately active (IRR = 1.30; 95% CI: 1.02-1.66; p = 0.01) and inactive (IRR = 1.33; 95% CI: 1.06-1.66; p = 0.01) participants had higher rates of psychiatric hospitalizations compared to active participants. Our findings suggest that lower levels of physical activity among AYAs were associated with an increased incidence of psychiatric hospitalizations, providing valuable insights for stakeholders and laying the groundwork for future research.