Effects of Cognitive Therapy for Depression on Insomnia in Women with Metastatic Breast Cancer

This study assessed the effects of cognitive therapy (CT) for depression on insomnia in women with metastatic breast cancer.

Thirty-four women with metastatic breast cancer and depressive symptoms were randomly assigned to CT for depression or a waitlist control group (WLC). Insomnia was measured using the Insomnia Severity Index (ISI) at pre-treatment (PRE) and posttreatment (POST), as well as 3 (FU3) and 6 (FU6) months later.

In the CT group, the proportion of women obtaining a clinically significant level of insomnia (ISI ≥8) decreased significantly from pre- to posttreatment (PRE = 80.0%; POST = 26.7%; p = .013). The mean ISI score differed significantly between groups at posttreatment/waiting (intervention = 5.5; control = 12.7; p = .048) and the ISI score decreased significantly from pre- to posttreatment (PRE = 11.5; POST = 5.5; p = .001). Additional analyses were performed pooling both groups together after WLC patients received CT. The proportion of patients with a clinical level of insomnia (PRE = 77.5%; POST = 28.3%; FU3 = 46.3%; FU6 = 21.0%; p < .0001), and the mean ISI score significantly decreased over time(PRE = 12.1; POST = 5.0; FU3 = 8.0; FU6 = 5.5; p < .0001).

Although insomnia improved over time, 21.0% to 46.3% of women reported residual insomnia symptoms following CT for depression. Therefore, a concomitant treatment that directly targets insomnia should be provided to women with cooccurring depression and insomnia.