JMIR Publications

ABSTRACT

Background:

Sleep disturbance symptoms (SDS) are common in major depressive disorder (MDD) and have been found to hamper the treatment effect of conventional face-to-face psychological treatments such as cognitive behavioral therapy (CBT). To increase the dissemination of evidence-based treatment, blended CBT (bCBT) consisting of online and face-to-face treatment is on the rise for MDD patients. To date, no study has examined whether SDS has an impact on bCBT treatment outcomes and whether it affects bCBT and treatment as usual (TAU) equally.

Objective:

The objectives of this study were to investigate: (1) whether baseline SDS have an impact on treatment outcomes independent of treatment modality, and (2) whether SDS impact bCBT and TAU in routine care equally.

Methods:

The study was based on data from the E-COMPARED study: a two-arm, multisite, parallel randomized controlled, non-inferiority trial. A total of 943 MDD outpatients were randomized to either (1): bCBT (n=476) or (2): TAU consisting of routine clinical MDD treatment (n=467). The primary outcome for the present study was the change of depression symptom severity at 12-months follow-up. Secondary outcomes were the change of depression symptom severity at 3- and 6-months follow-up and MDD diagnoses at 12-months follow-up, assessed with the Patient Health Questionnaire-9 (PHQ-9) and Mini-International Neuropsychiatric Interview (MINI), respectively. Mixed effects models were used to examine the association of SDS with treatment outcome and treatment modality over time.

Results:

558 of the 943 (59.17%) patients recruited for the study completed the 12-months follow-up assessment. On the total sample, baseline SDS did not significantly affect change in depressive symptom severity at twelve months follow-up (ß = .16, 95% CI [-.04, .36]). However, baseline SDS were negatively associated with treatment outcome for bCBT (ß = .49, 95% CI [.22, .76]) but not for TAU (ß = -.23, 95% CI [-.50, .05]) at 12-months follow-up, even when adjusting for baseline depression symptom severity. The same picture was seen for the effect of SDS on the presence of depression measured with MINI at 12-months follow-up. However, for both treatment formats baseline SDS were not associated with depression symptom severity at neither 3- (ß = .06, 95% CI [-.11, .23]) nor 6-months (ß = .09, 95% CI [-.10, .28]) follow-up.

Conclusions:

Baseline SDS may have a negative impact on long-term treatment outcomes in bCBT for MDD. This effect was not present for TAU. These findings suggest that special attention to SDS might be warranted when MDD is treated with bCBT. Future studies should investigate the effect of implementing modules specifically targeting SDS in bCBT for MDD to improve the long-term prognosis. Clinical Trial: ClinicalTrials.gov: France: NCT02542891; Poland: NCT02389660; Spain: NCT02361684; Sweden: NCT02449447; Switzerland: NCT02410616; other clinical databases: Germany: German Clinical Trials Register DRKS00006866; The Netherlands: Netherlands Trials Register NTR4962; United Kingdom: ISRCTN registry, ISRCTN12388725; Denmark: ClinicalTrials.gov NCT02796573