To Örebro University

Objective: Cognitive behavioral therapy for insomnia (CBT-I) is the first-line treatment for insomnia, but half of the patients do not reach remission. This study aimed to explore subjective remission by investigating the characteristics of patients who reported lingering sleep problems after CBT-I.

Methods: Secondary analyses of a randomized controlled trial of group CBT-I in 72 primary care patients with insomnia disorder. Sociodemographic characteristics and outcomes (insomnia severity, sleep variables, hypnotics use, fatigue, depressive symptoms, and dysfunctional beliefs/attitudes), including baseline data and symptom change, were investigated in relation to patients' posttreatment response to the yes-or-no question “Would you say that you have sleep problems?”

Results: A total of 56.9% of patients reported sleep problems after CBT-I. At baseline, they had worse depressive symptoms (14.9 (SD 7.5) vs. 10.2 (SD 5.9), p = 0.006) and more awakenings (2.6 (SD 1.5) vs. 1.8 (SD 1.3), p = 0.034) than those in subjective remission from sleep problems. Patients in the non-remission and remission groups showed similar improvements in sleep, fatigue, and depressive symptoms, but patients in the non-remission group had improved less in insomnia severity, dysfunctional beliefs/attitudes about sleep, and hypnotic use. In patients with more pronounced depressive symptoms before CBT-I, change in depressive symptoms during treatment partially explained subjective remission from sleep problems.

Discussion: More severe depressive symptoms prior to CBT-I and less improvements in depressive symptoms during treatment predicted remaining subjective sleep problems after treatment. These findings highlight the importance of assessing depressive symptoms in primary care patients with insomnia, as patients with pronounced depressive symptoms may need tailored treatment.