TY - JOUR
T1 - Chronotype and improved sleep efficiency independently predict depressive symptom reduction after group cognitive behavioral therapy for insomnia
AU - Bei, Bei
AU - Ong, Jason
AU - Rajaratnam, Shanthakumar M W
AU - Manber, Rachel
PY - 2015
Y1 - 2015
N2 - Study Objectives: Cognitive behavioral therapy for insomnia (CBT-I) has been shown to improve both sleep and depressive symptoms, but predictors of depression outcome following CBT-I have not been well examined. This study investigated how chronotype (i.e., morningness-eveningness trait) and changes in sleep effi ciency (SE) were related to changes in depressive symptoms among recipients of CBT-I. Methods: Included were 419 adult insomnia outpatients from a sleep disorders clinic (43.20 males, age mean ? standard deviation = 48.14 ? 14.02). All participants completed the Composite Scale of Morningness and attended at least 4 sessions of a 6-session group CBT-I. SE was extracted from sleep diary; depressive symptoms were assessed using the Beck Depression Inventory (BDI) prior to (Baseline), and at the end (End) of intervention. Results: Multilevel structural equation modeling revealed that from Baseline to End, SE increased and BDI decreased signifi cantly. Controlling for age, sex, BDI, and SE at Baseline, stronger evening chronotype and less improvement in SE signifi cantly and uniquely predicted less reduction in BDI from Baseline to End. Chronotype did not predict improvement in SE. Conclusions: In an insomnia outpatient sample, SE and depressive symptoms improved signifi cantly after a CBT-I group intervention. All chronotypes benefi ted from sleep improvement, but those with greater eveningness and/or less sleep improvement experienced less reduction in depressive symptom severity. This suggests that evening preference and insomnia symptoms may have distinct relationships with mood, raising the possibility that the effect of CBT-I on depressive symptoms could be enhanced by assessing and addressing circadian factors.
AB - Study Objectives: Cognitive behavioral therapy for insomnia (CBT-I) has been shown to improve both sleep and depressive symptoms, but predictors of depression outcome following CBT-I have not been well examined. This study investigated how chronotype (i.e., morningness-eveningness trait) and changes in sleep effi ciency (SE) were related to changes in depressive symptoms among recipients of CBT-I. Methods: Included were 419 adult insomnia outpatients from a sleep disorders clinic (43.20 males, age mean ? standard deviation = 48.14 ? 14.02). All participants completed the Composite Scale of Morningness and attended at least 4 sessions of a 6-session group CBT-I. SE was extracted from sleep diary; depressive symptoms were assessed using the Beck Depression Inventory (BDI) prior to (Baseline), and at the end (End) of intervention. Results: Multilevel structural equation modeling revealed that from Baseline to End, SE increased and BDI decreased signifi cantly. Controlling for age, sex, BDI, and SE at Baseline, stronger evening chronotype and less improvement in SE signifi cantly and uniquely predicted less reduction in BDI from Baseline to End. Chronotype did not predict improvement in SE. Conclusions: In an insomnia outpatient sample, SE and depressive symptoms improved signifi cantly after a CBT-I group intervention. All chronotypes benefi ted from sleep improvement, but those with greater eveningness and/or less sleep improvement experienced less reduction in depressive symptom severity. This suggests that evening preference and insomnia symptoms may have distinct relationships with mood, raising the possibility that the effect of CBT-I on depressive symptoms could be enhanced by assessing and addressing circadian factors.
UR - http://www.aasmnet.org/jcsm/ViewAbstract.aspx?pid=30172
U2 - 10.5664/jcsm.5018
DO - 10.5664/jcsm.5018
M3 - Article
SN - 1550-9389
VL - 11
SP - 1021
EP - 1027
JO - Journal of Clinical Sleep Medicine
JF - Journal of Clinical Sleep Medicine
IS - 9
ER -