Antidepressant use in older age bipolar disorder (OABD): Results from the GAGE-BD international consortium

Background Antidepressants are still commonly prescribed in bipolar disorders, despite ongoing controversy of the potential risk of inducing hypomania/mania. There is limited knowledge about the characteristics of antidepressant use in older age bipolar disorder (OABD; age ≥50) in the current literature. Aim To describe antidepressant use, sociodemographic and clinical correlates of a global sample of OABD individuals. Methods The Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) consortium provided cross-sectional international data on OABD individuals ( n = 746) and younger-age bipolar disorder (YABD, age <50 years; n = 692) regarding antidepressant use. Multivariate logistic regression was employed to assess the association between AD use with demographic and clinical variables. Results Of 1252 participants, 33.1 % of OABD individuals and 38.1 % of YABD individuals were using antidepressants. In multivariable models among OABD, antidepressant use was associated with BD type II (OR = 1.61, 95 % CI: 1.09–2.38), higher depression severity (mild-to-moderate: OR = 1.86, 95 % CI: 1.13–3.06; severe: OR = 4.23, 95 % CI: 2.38–7.50), lower YMRS scores (OR = 0.93, 95 % CI: 0.89–0.97), female sex (OR = 1.37, 95 % CI: 1.00–1.89), lower education (OR = 0.61, 95 % CI: 0.43–0.86), and being unemployed (OR = 0.69, 95 % CI: 0.50–0.96). Antidepressant monotherapy was reported in 18 % of OABD users ( n = 46) and 19 % of YABD users ( n = 51). These findings suggest that both clinical severity and sociodemographic characteristics influence antidepressant prescribing in OABD. Conclusion Antidepressant use was less prevalent in OABD compared to YABD, and associated with female sex, lower education, lack of occupation, type II BD, higher depression severity and lower mania scores. In OABD, antidepressants appear to be used more commonly in contexts where they may be clinically more indicated, such as increased depression severity.