Risk of self-harm in post TIA patients: A population-based cohort study.

Objective: The purpose of this study was to determine whether individuals who have experienced a transient ischemic attack (TIA) have an increased risk of self-harm behaviors.

Methods: In this matched cohort study, we reviewed the electronic health records of all patients admitted for any reason to Hong Kong public hospitals between January 1, 1993, and December 31, 2019. We selected a post-TIA cohort consisting of 37,356 patients and a comparison cohort comprising 37,352 subjects. All participants enrolled in this study were followed up until a diagnosis of self-harm, death from other causes, or the end of 2020, whichever occurred first. Univariate Cox proportional hazards regression models were used to calculate the risk of self-harm since the onset of TIA.

Results: Throughout the 27-year study period, the number of individuals exhibiting self-harm behavior in the TIA and comparison groups was 1031 (2.76%) and 512 (1.37%), respectively. The TIA group had a higher proportion of subjects with self-harm (χ = 178, p < .001). The incidence rates of self-harm were 33.94 and 19.27 per 10,000 person-years in TIA patients and comparators, respectively. Compared with the comparators, the adjusted hazard ratio for self-harm in TIA patients was 1.63 (95% confidence interval, 1.46-1.82).

Conclusions: TIA is associated with an increased risk of self-harm. Healthcare professionals should help identify patients at heightened risk and provide efficient and targeted prevention strategies for this population.