The effect of loneliness and social support on the course of major depressive disorder among adults aged 50 years and older: A longitudinal study

Background Previous research indicates that social support, loneliness, and major depressive disorder (MDD) are interrelated. Little is known about the potential pathways among these factors, in particular in the case of adults aged 50 years and older and suffering from MDD. The objective was to investigate whether loneliness mediates the association between low social support and recurrent episodes of MDD. Methods We used data from a cohort of the Spanish general population interviewed at three time-points over a 7-year period. We included 404 individuals aged 50+ suffering from MDD in the baseline assessment. A 12-month major depressive episode was assessed with the Composite International Diagnostic Interview (CIDI) at each interview. The University of California, Los Angeles Loneliness Scale was used to measure loneliness, whereas social support was assessed through the Oslo Social Support Scale. We tested cross-lagged and autoregressive longitudinal associations using structural equation modeling. Results We identified two significant longitudinal mediation patterns: lower social support predicted higher subsequent levels of loneliness (Coef. = -0.16; p < .05), which in turn predicted an increase in MDD recurrence (Coef. = 0.05; p < .05). Conclusions Interventions focused on promoting social support among older adults suffering from MDD may decrease feelings of loneliness and prevent recurrent episodes of MDD.