Mood Disorders after Traumatic Brain Injury in Adolescents and Young Adults: A Nationwide Population-Based Cohort Study

Objective To delineate the relationship between traumatic brain injury (TBI) and mood disorders from population-based data in Taiwan. Study design This prospectively followed cohort study involved a subset of the National Health Insurance Research Database containing complete inpatient and outpatient data of 1 million randomly drawn beneficiaries. We included 10- to 24-year-old patients (n = 15 203) receiving the diagnosis of TBI in ambulatory visits or hospitalization from 2000-2004 and their age-and sex-matched comparison insureds using health service in the same year (n = 76 015). Diagnosis of mood disorders was recorded within 5 years after the traumatic event or index use of health service. Baseline demographics, clinical characteristics, and premorbid psychiatric conditions were compared using chi(2) analysis. Increased risk during the 5-year follow-up period was represented by crude and adjusted hazard ratios with 95% CI using a Cox proportional hazard regression. Results A total of 451/15 203 patients with TBI (2.97%) received a diagnosis of mood disorders in the 5-year follow-up period compared with 1153/97 445 individuals (1.52%) without antecedent TBI. After adjusting for select premorbid comorbidities, TBI remained a significant predisposing factor with a 1.96-fold (95% CI 1.74-2.22) increase in risk of mood disorders. Conclusions Our findings show a higher likelihood of manifesting mood disorders in adolescents and young adults who sustained a prior TBI. Health professionals should carefully monitor both the physical and psychological impacts of head trauma.