The role of late life depressive symptoms on the trajectories of insomnia symptoms during antidepressant treatment

Objective: Sleep disturbances are common in late life depression; however, changes in insomnia symptoms during antidepressant treatment need to be characterized further. The objective of this study was two-fold: 1) to describe longitudinal trajectories of insomnia symptoms in older adults receiving antidepressant treatment and 2) to examine whether baseline depressive symptoms were associated with trajectories of sleep over time. Methods: Data was obtained from 680 older adults (aged 60) with major depression who participated in one of two protocolized open-label antidepressant treatment clinical trials (Maintenance Therapies in Late Life Depression [MTLD-3]; Incomplete Response in Late Life Depression: Getting to Remission [IRL-GRey]). Depression (total score minus sleep items) and sleep (sum of sleep items) outcomes were derived from the Hamilton Depression Rating Scale in the MLTD-3 and Montgomery-Asberg Depression Rating Scale in the IRLGRey. Results: Both datasets identified 5 possible trajectories of insomnia symptoms with about half of the older adults having clinically significant baseline sleep disturbances and minimal improvement following a course of antidepressant treatment (i.e., sub-optimal sleep trajectory). Furthermore, across both datasets, worse baseline depression severity was associated with sub-optimal sleep trajectories. Conclusion: In older adults receiving antidepressant treatment, those with clinically significant baseline sleep disturbances and greater depression severity may require adjunctive sleep-focused treatment to ameliorate sleep symptoms.