Sex differences in suicide, suicidal ideation, and self‑harm after release from incarceration: A systematic review and meta‑analysis

Purpose People released from incarceration are at increased risk of suicide compared to the general population. We aimed to synthesise evidence on the incidence of and sex differences in suicide, suicidal ideation, and self-harm after release from incarceration. Methods We searched MEDLINE, EMBASE, PsycINFO, Web of Science and PubMed between 1 January 1970 and 14 October 2021 for suicide, suicidal ideation, and self-harm after release from incarceration (PROSPERO registration: CRD42020208885). We calculated pooled crude mortality rates (CMRs) and standardised mortality ratios (SMRs) for suicide, overall and by sex, using random-effects models. We calculated a pooled incidence rate ratio (IRR) comparing rates of suicide by sex. Results Twenty-nine studies were included. The pooled suicide CMR per 100,000 person years was 114.5 (95%CI 97.0, 132.0, I2 = 99.2%) for non-sex stratified samples, 139.5 (95% CI 91.3, 187.8, I2 = 88.6%) for women, and 121.8 (95% CI 82.4, 161.2, I2 = 99.1%) for men. The suicide SMR was 7.4 (95% CI 5.4, 9.4, I2 = 98.3%) for non-sex stratified samples, 14.9 for women (95% CI 6.7, 23.1, I2 = 88.3%), and 4.6 for men (95% CI 1.3, 7.8, I2 = 98.8%). The pooled suicide IRR comparing women to men was 1.1 (95% CI 0.9, 1.4, I2 = 82.2%). No studies reporting self-harm or suicidal ideation after incarceration reported sex differences. Conclusion People released from incarceration are greater than seven times more likely to die by suicide than the general population. The rate of suicide is higher after release than during incarceration, with the elevation in suicide risk (compared with the general population) three times higher for women than for men. Greater effort to prevent suicide after incarceration, particularly among women, is urgently needed.