ABSTRACT: OBJECTIVE:Antidepressant medications have a variety of effects on sleep, apart from their antidepressant effects. It is unknown whether electroconvulsive therapy (ECT) has effects on perceived sleep in depressed patients. This secondary analysis examines the effects of ECT on perceived sleep, separate from its antidepressant effects. METHODS:Elderly patients with major depressive disorder, as defined by DSM-IV, received open-label high-dose, right unilateral ultrabrief pulse ECT, combined with venlafaxine, as part of participating in phase 1 of the National Institute of Mental Health-supported study Prolonging Remission in Depressed Elderly (PRIDE). Phase 1 of PRIDE participant enrollment period extended from February 2009 to August 2014. Depression severity was measured with the Hamilton Depression Rating Scale-24 item (HDRS??), and measures of insomnia severity were extracted from the HDRS??. Participants were characterized at baseline as either "high-insomnia" or "low-insomnia" subtypes, based upon the sum of the 3 HDRS?? sleep items as either 4-6 or 0-3, respectively. Insomnia scores were followed during ECT and were adjusted for the sum of all the HDRS?? non-sleep items. Generalized linear models were used for longitudinal analysis of insomnia scores. RESULTS:Two hundred forty patients participated, with 48.3% in the high-insomnia and 51.7% in the low-insomnia group. Although there was a reduction in the insomnia scores in the high-insomnia group, only 12.4% of them experienced remission of insomnia after a course of ECT, despite an increase in utilization of sleep aids across the course of ECT, from 8.6% to 23.2%. The degree of improvement in insomnia symptoms paralleled the degree of improvement in non-insomnia symptoms. A "low" amount of improvement on the sum of the HDRS non-insomnia items (HDRS-sleep) was accompanied by a "low" amount of improvement in insomnia scores (change of -1.6 ± 1.2, P < .0001), while a "high" amount of improvement on the sum of the HDRS non-insomnia items was accompanied by a "higher" amount of improvement in insomnia scores (change of -3.1 ± 1.6, P < .0001). After adjustment for non-insomnia symptoms, there was no change in insomnia in the low-insomnia group. CONCLUSIONS:We found that ECT, combined with venlafaxine, has a modest anti-insomnia effect that is linked to its antidepressant effect. Most patients will have some degree of residual insomnia after ECT, and will require some consideration of whether additional, targeted assessment and treatment of insomnia is warranted. TRIAL REGISTRATION:ClinicalTrials.gov Identifier: NCT01028508.
