A short-term longitudinal examination of the relations between depression, anhedonia, and self-injurious thoughts and behaviors in adults with a history of self-injury

Background
Limited research has addressed the role of anhedonia in predicting suicidality and/or nonsuicidal self-injury (NSSI) in adults, despite evidence suggesting that loss of interest or pleasure may increase vulnerability for self-inflicted harm, even beyond other depressive symptoms.
Methods
In the current study, we explored the role of symptoms of depression and recent changes in anhedonia in predicting suicidality, NSSI ideation, and perceptions of NSSI helpfulness among individuals with a history of NSSI or suicide attempts (N = 187).
Results
We found that changes in anhedonia partially mediated the effect of depression on suicidality, and fully mediated the effect of depression on perceptions of NSSI helpfulness. Anhedonia did not predict NSSI ideation above and beyond depression symptoms, and did not significantly predict NSSI frequency when accounting for suicidality. Compared to individuals with a history of NSSI only or suicide attempt only, people with a history of both NSSI and suicide attempt evidenced greater risk and symptomatology.
Conclusions
Results confirm the relation between anhedonia and suicidality evidenced in past research, but suggest a complex relationship between anhedonia, depression, and facets of non-suicidal self-injury.