Outpatient mental health service use in major trauma survivors: a population-based cohort study from Ontario, Canada

Background — Mental health is recognized as an important outcome in major trauma survivors. There is limited data on how and when survivors access mental health services. Our objectives were to determine the frequency, timing, and factors associated with outpatient mental health service utilization in major trauma survivors.

Methods — We conducted a population-based cohort study using linked administrative data on patients treated for major trauma in Ontario between 2009 and 2017. All trauma survivors were included in the cohort, and composite rates of outpatient mental health service use (Family doctor, Psychiatrist, or Emergency department visits) were compared in the three years pre- and post-injury. We used an exposure crossover study design and negative binomial regression with generalized estimating equations for the analysis. Multivariate logistic regression analyses were used to identify patient characteristics associated with mental health service use during the follow up period.

Results — There were 37,260 patients included in the cohort, predominantly men (70.8%) from urban areas (84.8%) suffering blunt trauma (89.7%). 47.4% of patients utilized mental health services during the pre-injury period and 61.8% post-injury period (absolute increase of 14.4%). Compared to the three years pre-injury, the rate of mental health service use increased by 80% (Rate ratio 1.8, 95% confidence interval 1.75 – 1.77) in the three years following injury. Most survivors (62.2%) used services within the first year following discharge. Post-injury mental health service use (Adjusted odds ratio 3.4, 95% CI: 2.2-3.7) was most strongly associated with pre-injury mental health service use.

Conclusion — Pre- and post-injury outpatient mental health service use is common in trauma patients, with pre-injury service use predictive of ongoing service use. Mental health concerns should be an expected outcome of major trauma and efforts made to implement and expand access to services for injury survivors across trauma systems.