What are sociodemographic and gender determinants of non-fatal self-harm in older adults users and non-users of antidepressants? A national population-based study

Abstract

Background Late-life self-harm (SH) is often linked to depression. However, very few studies have explored the role of other factors and their interaction with depression in the occurrence of late-life SH. The objective of this research was to examine sociodemographic and gender factors associated with non-fatal SH, in older adults with and without antidepressant therapy. Methods We used national longitudinal register data from a total cohort of all Swedish residents aged ≥75 years between 2006-2014 (N=1,413,806). Using personal identity numbers, we linked individuals' data from numerous national registers. We identified all those with at least one episode of non-fatal self-harm (regardless of level of intent to die) and matched 50 controls to each case. A nested case–control design was used to investigate the sociodemographic factors associated with non-fatal SH in the total cohort and among antidepressant users and non-users. Risk factors were analysed in adjusted conditional logistic regression models for the entire cohort and by gender. Results In all, 2242 individuals had at least one episode of a non-fatal SH (980 men and 1262 women). In the total cohort, being married was a protective factor for non-fatal SH in men but not in women. A higher non-fatal SH risk was found in antidepressant users from outside Nordic countries (IRR: 1.44; 95% CI: 1.11-1.86), and in non-users of antidepressants from other Nordic countries (IRR: 1.58; 95% CI: 1.08-2.29). Antidepressant users with higher education had an increased risk of non-fatal SH (IRR: 1.34; 95% CI: 1.12-1.61), in both men and women. Conclusions Being married did not mitigate risk of self-harm in older women. Foreign country of birth and higher education were associated with increased risk of non-fatal SH. Healthcare professionals and social workers must be informed about high-risk groups for suicidal behaviour, and ensure they are adequately monitored both in term of antidepressant therapy and access to psychosocial support.