Suicide and Self-Injury
Perceived burdensomeness, thwarted belongingness and interoceptive deficits: a commonality approach to non-suicidal self-injury
Ronan L. Wilson, B.A.
Student
University of South Florida
Oviedo, Florida
Allison Cunning, M.A.
Graduate Student
University of South Florida
Tampa, Florida
Diana Rancourt, Ph.D.
Associate Professor
University of South Florida
Tampa, Florida
The Interpersonal Theory of Suicide (IPTS) has been a dominant theory among suicide research and prevention efforts. Non-suicidal self-injury (NSSI) is one of the single most powerful predictors of a future suicide attempt, and yet the constructs of the ITPS have not been applied to NSSI. While the same interpersonal factors that drive suicidal ideation - perceived burdensomeness (PB) and thwarted belongingness (TB) - may function similarly for NSSI, only two studies have PB and TB in the context of NSSI, with mixed findings. The third pillar in the IPTS, acquired capability – the ability for an individual to engage in a lethal suicide attempt – is heavily focused on death. Acquired capability may be of limited use for predicting NSSI due to its focus on death. Instead, interoceptive deficits – one’s inability to accurately sense and identify physiological sensations - may be an appropriate substitute when applying the IPTS to NSSI given that individuals who engage in NSSI have greater interoceptive deficits. There is a dearth of research investigating predictors of NSSI. Given that NSSI is one of the strongest predictors of suicide, the present study addressed this gap in the literature by first comparing levels of TB, PB, and interoceptive deficits between those with a history of NSSI and those who do not. Secondly, the study used a commonality approach to test which factors accounted for the greatest variance in lifetime NSSI engagement – it was predicted that the common variance of the combined factors would be greater than any of the individual factors.
A total of 291 university students completed measures of TB and PB (Van Orden et al., 2012), pain interoceptive deficits (McCracken, 1997), emotional interoceptive deficits (Mehling et al., 2018), and NSSI (Fox et al., 2020). Targeted recruitment was used to obtain approximately equal groups of those with a history of NSSI engagement (n=136; Mage= 19.44; 83.8% female; White = 92; Black = 17; Asian = 15; Other = 9; Hispanic = 28,) and those with no history of NSSI (n=155; Mage= 19.50; 65.2% female; White = 81; Black = 28; Asian = 16; Other = 21; Hispanic = 42; group demographics). Mann-Whittney U-Tests examined differences between the NSSI group and non-NSSI group in PB, TB, pain and emotional interoceptive deficits. A commonality analysis was conducted among those with endorsed NSSI to determine which factors were associated with the greatest amount of variance in lifetime NSSI engagement. Compared to individuals without NSSI, individuals with a lifetime history of NSSI were significantly higher in PB (MdnNSSI=12.0 vs. Mdn=6.0, U=6320.5, p < .000, r=.355) and TB (MdnNSSI=30.0 vs. Mdn=25.0, U=8157.5, p =.002, r=.185) and significantly lower in emotional interoceptive deficits (MdnNSSI=1.4 vs. MdnNon-NSSI=1.8, U=8938.5, p = .025, r=.129). Commonality analysis showed that PB was uniquely associated with (35.20%) of the variance in lifetime NSSI engagement, while pain interoceptive deficits (32.86%), TB (2.58%), and emotional interoceptive deficits (1.89%) followed. Findings suggest that the interpersonal factors of the IPTS are significantly higher in those who engage in NSSI, and that PB and pain interoceptive deficits may represent novel intervention and prevention targets for engagement in NSSI.