Pain analgesia or desensitization? A longitudinal lab-based study on the link between pain and nonsuicidal self-injury.

Mounting evidence suggests that individuals who engage in nonsuicidal self-injury (NSSI) have lower pain sensitivity (e.g., pain thresholds and tolerances) than individuals without a history of NSSI. However, research has been largely cross-sectional, so it is unclear whether low pain sensitivity may increase risk for NSSI, or whether NSSI diminishes pain sensitivity over time. In the present study, the relations among NSSI frequency, versatility (number of NSSI methods), pain threshold, and pain tolerance were examined using a longitudinal research design. Participants included 156 undergraduate students at a large university (87% female; Mage = 19.79) with a recent history of NSSI. Participants reported on their NSSI engagement and completed a cold pressor task in a baseline session, as well as at one year follow-up. Eight regression models were run to examine the nature of the association between the two pain measures (i.e., pain threshold and tolerance) and the two NSSI measures (i.e., frequency and versatility). Pain tolerance and pain threshold predicted NSSI versatility over time, but NSSI frequency and versatility did not predict pain threshold or tolerance over time. Results suggest that low pain sensitivity may be a risk factor for severe NSSI engagement.