Background: The incidence, determinants and impact of developing a new mental health condition after trauma are unclear.
Methods: After obtaining ethics approval, 65,555 and 198,395 public or private hospitalisations before and after the first (or index) trauma admissions, respectively, of 29,191 trauma patients, were linked to Trauma Registry to define the medical journey of each trauma patient. Cox proportional hazards was used to identify predictors of all-cause and suicide-related mortality, and trauma readmissions.
Results: Males were overrepresented (66.4%) in our trauma patients, and the median age, Injury Severity Score, and follow-up time of the whole cohort were 42 years-old, 9, and 99.8 months, respectively. Two thousand and thirty-three patients (7.6%) had a mental health condition prior to their first trauma admissions; and of those without a prior mental health condition (N=26,958), 3299 (12.2%) developed a mental health condition after their first trauma admission, with a relatively high incidence of drug dependence (n=2391, 8.2%) and neurotic disorders (n=1574, 5.4%) including Post-Traumatic Stress Disorder. Developing a new mental health condition after trauma was predictive of subsequent trauma readmissions (hazard ratio [HR] 1.30, 95% confidence interval [CI] 1.23-1.37; p<0.001), suicides from hanging or drug overdoses (HR 3.14, 95%CI 2.00-4.91; p<0.001) and all-cause mortality (HR 1.24, 95%CI 1.12-1.38; p<0.001). Age, employment status, marital status, ethnicity, and socioeconomic status were all predictive of developing a new mental health condition after the first trauma admission.
Conclusions: Developing a new mental health condition after trauma was common and associated with an increased risk of adverse long-term outcomes.