Methods and efficacy of social support interventions in preventing suicide: a systematic review and meta-analysis

Suicide is a global public and mental health problem. The effectiveness of social support interventions has not been widely demonstrated in the prevention of suicide. We aimed to describe the methods of social support interventions in preventing suicide and examine the efficacy of them.

We searched literature databases and conducted clinical trials. The inclusion criteria for the summary of intervention methods were as follows: (1) studies aimed at preventing suicide through method(s) that directly provide social support; (2) use of one or more method(s) to directly provide social support. The additional inclusion criteria for meta-analysis on the efficacy of these interventions included: (1) suicide, suicide attempt or social support-related outcome was measured; (2) randomised controlled trial design and (3) using social support intervention as the main/only method.

In total, 22 656 records and 185 clinical trials were identified. We reviewed 77 studies in terms of intervention methods, settings, support providers and support recipients. There was a total of 18 799 person-years among the ten studies measuring suicide. The number of suicides was significantly reduced in the intervention group (risk ratio (RR)=0.48, 95% CI 0.27 to 0.85). In 14 studies with a total of 14 469 person-years, there was no significant reduction of suicide attempts in the overall pooled RR of 0.88 (95% CI 0.73 to 1.07).

Social support interventions were recommended as a suicide prevention strategy for those with elevated suicide risk.