Identifying subgroups within a sample of adults with a suicide attempt history using the Interpersonal Psychological Theory of Suicide

This study used a novel theory-informed latent class approach, based on the Interpersonal Psychological Theory of Suicide (IPTS), to identify subgroups of individuals with a suicide attempt history. The identification of subgroups can inform treatments that target these specific subgroups. Using data from a randomised controlled trial, latent class analysis was conducted on 227 adults with a suicide attempt history. Latent classes were identified based on suicide attempt history, perceived burdensomeness, thwarted belongingness, and capability for suicide at the trial baseline. Three classes were found. Classes 1 and 2 (80% of participants) at baseline had higher interpersonal risks and clinical symptoms, and lower protective psychological factors (e.g., positive reframing), compared to Class 3 (20% of participants). Class 1 had elevated suicidal ideation for the duration of the trial. Classes 1 and 2 also had elevated interpersonal risks relative to a population-based sample. These results suggest that some individuals with a suicide attempt history exhibit relatively low interpersonal risks, and given concurrent protective psychological factors, may be suited to low-intensity interventions. At the other extreme, some individuals with a suicide attempt history require high-intensity interventions addressing interpersonal risks, clinical symptoms, and protective psychological factors.This study was supported by a grant from the Australian National Health and Medical Research Council (NHMRC; GNT1046317) and forms part of the program of research conducted by the NHMRC Centre of Research Excellence in Suicide Prevention (GNT1042580). PJB, ALC, MT and HC are supported by NHMRC fellowships 1158707, 1122544, 1138710 and 1056964