A latent class analysis of non-suicidal self-injury and associations with constructs from the interpersonal theory of suicide in a sample of sexual minority young adults

Introduction: Self-directed violence (SDV), comprising both non-suicidal self-injury (NSSI) and suicide, is elevated among sexual minority populations. NSSI age of onset has been shown to impact severity of SDV outcomes. Components of the Interpersonal Theory of Suicide (ITS), which includes perceived burdensomeness (PB), thwarted belongingness (TB), and acquired capability for suicide (ACS), may be useful to understanding NSSI subgroups, especially among under-researched groups such as sexual minority persons. Methods: This study examined subtypes of NSSI and associations with constructs from the ITS. A sample of 473 sexual minority young adults with a history of NSSI completed self-report measures assessing demographics, SDV, and ITS constructs. More than half of the sample (59.7%) reported engaging in NSSI during their lifetime. For suicidal thoughts and behaviors, a majority of the sample reported having thoughts of suicide in their lifetime (87.3%), and one-third reported a lifetime suicide attempt (33.0%). Results: Latent class analysis revealed three classes: (1) lower NSSI, (2) moderate NSSI, and (3) higher NSSI. NSSI age of onset, intensity of suicidal thoughts, suicide plan likelihood, duration of NSSI, and number of NSSI methods differentiated groups. Multivariate Analysis of Variance (MANOVA) revealed that the lower NSSI group reported lower PB and TB than the moderate NSSI group. No differences were found for ACS across NSSI classes. Discussion: Results are discussed in terms of their theoretical implications and application for counseling at-risk sexual minority young adults. This study identifies factors associated with subgroups of self-directed violence among sexual minority young adults. Such findings inform gaps in self-directed violence prevention research and clinical practice for sexual minority persons.