0362 LONG-TERM FOLLOW UP OF THE EFFICACY OF COGNITIVE BEHAVIORAL THERAPY FOR INSOMNIA (CBT-I) IN RELATION TO DEPRESSIVE SYMPTOMS

Abstract

Depressive symptoms very often are co-existing with insomnia. Cognitive behavioral treatment for insomnia (CBT-I) has been demonstrated to improve also symptoms of depression. This study evaluated whether depressive symptom severity is associated with poorer response to CBT-I at the end of 7-session treatment (T1) and at a long-term follow of a mean of 7.8 ± 1.6 years (range 4–10 years) (T2). Non-randomized retrospective study of 286 sleep clinic patients (mean age 40.7 ± 12.3, 38.4% males, 61.6% females) with chronic insomnia who completed 7-session group CBT-I. We compared low depression (LD) and high depression (HD) groups, based on a cutoff of 14 on the Beck Depression Inventory (BDI). Compared to baseline (T0), a significant decrease of ISI and BDI scores were observed in both LD and HD groups at the end of treatment (T1) and at the long-term follow-up (T2) (P<.001). HD group improved more than LD group in both ISI and BDI scores. ISI scores of the LD patients were 15.9 ± 4.3 at T0, 9 ± 3.9 at T1, p<.05 and 8.5 ± 5.2 at T2. BDI was 7.8 ± 3.5 at T0, 4.8 ± 3.6 at T1, p<.05 and 5.7 ± 3.7 at T2. Delta score for ISI at T1 was 7.5 ± 4.8 and 6.5 ± 5.1 at T2 while for BDI 2.8 ± 5.1 at T1 and 0.59 ± 6.1 at T2.HD patient’s ISI scores were 19.5 ± 3.7 at T0, 12.7 ± 4.8 at T1, p<.05 and 15.6 ± 6.5 at T2. Delta score for ISI at T1 was 8.8 ± 5 and 8.1 ± 7.1 at T2 while for BDI 9.9 ± 7 at T1 and 6 ± 8.2 at T2. Results demonstrate that CBT-I improved not only insomnia severity but also comorbid depressive symptoms at the end of treatment. Improvements were sustained at a long-term follow-up evaluation after a mean of 7.8 years. Greater depression symptoms did not lead to poorer response to CBT-I. Thus, the benefits of CBTI are sustained long-term, and extend beyond insomnia and include improvement in depressive symptoms severity. None.