Responses to social defeat in early- vs late-onset suicidal behavior: an experimental behavioral study

Background:Social defeat is often cited as a motive for suicide. The experience of defeat may arise from feeling dominated in a dyadic conflict or from losing status in a group. We hypothesize that sensitivity to dyadic defeat will be related to the onset of suicidal behavior in early or mid-life and sensitivity to loss of status, in late life.Methods:The study’s sample of 245 adults aged 50+ years (mean=63.2 years, SD=7.4) comprised 42 early-onset and 32 late-onset suicide attempters (aged <50 vs ≥50 years at first attempt), 114 depressed non-attempter comparisons, and 57 non-psychiatric comparisons. Using a validated rigged video game tournament task, we operationalized compensatory responses to the two forms of social defeat as point stealing from individual opponents (one-on-one defeat) and rank buying in the league table (loss of status in a group).Results:Early-onset attempters increased point stealing the most over time (χ23=22.37, p<.001), whereas late-onset attempters purchased more rank after losing trials than early-onset attempters and non-psychiatric comparisons (χ23=9.47, p=.024). Each effect was robust to controlling for confounds including age and sex, other effects of interest, and to the exclusion of stereotypic responders.Conclusions:Our behavioral findings suggest that socio-behavioral processes leading to suicide vary across the life cycle. While vulnerability to dyadic defeat could be suicidogenic for people of any age, loss of social status could play a role in suicidal crises specifically occurring in later life.