Associations of anxiety sensitivity with non-suicidal self-injury and suicide attempts

Although non-suicidal self-injury (NSSI) and suicide attempts (SA) frequently co-occur, they may arise from distinct mechanisms. Although both NSSI and SA are associated with anxiety sensitivity, their association with multidimensional components of anxiety sensitivity may differ. We aimed to determine whether the dimensions of anxiety sensitivity differ across self-harm phenotypes based on NSSI and SA histories. Medical records of 5363 adult psychiatric outpatients were retrospectively reviewed. They were classified into four groups based on lifetime histories of NSSI and SA: neither NSSI nor SA, NSSI only, SA only, and both NSSI and SA. Anxiety sensitivity was assessed using the Anxiety Sensitivity Index-3 (ASI-3). The scores for the physical, social, and cognitive concern subscales of the ASI-3 were compared across groups after adjusting for demographic variables, medical comorbidity, and severity of depressive and anxiety symptoms. There were significant between-group differences across all dimensions of anxiety sensitivity. The physical concern scores were higher in individuals with NSSI and SA histories than in those with an SA history alone. Among participants without a SA history, the social concern scores differentiated individuals with a NSSI history from those without. The cognitive concern scores were higher in individuals with a NSSI history than in those without, regardless of SA history. The physical, social, and cognitive dimensions of anxiety sensitivity showed distinct patterns across self-harm phenotypes in psychiatric outpatients. Based on these findings, anxiety sensitivity is a multidimensional construct that may relate differently to NSSI and SA.