Seven-hour sleep duration increases chances of achieving remission in depressed patients with insomnia

Preliminary results from a new study show that depressed patients with insomnia who sleep seven or more hours per night are more likely to benefit from cognitive behavioral therapy for insomnia (CBTI) and achieve depression remission.

Results show that when insomnia and depression co-occur, longer pre-treatment objective sleep duration is predictive of remission of both disorders when patients are given a combination of CBTI for insomnia and antidepressant medication for depression.

"A seven-hour, objective sleep duration of patients prior to entering treatment increased their chances of achieving both depression and insomnia remission by their treatment endpoints," said lead author and co-principal investigator Jack D. Edinger, PhD, professor in the Section of Sleep Medicine at National Jewish Health in Denver, Colorado.

The study involved 104 adults, including 75 women, who enrolled in the Treatment of Insomnia and Depression Study and completed one baseline night of polysomnography. Participants received 16 weeks of anti-depressant medication and were randomly assigned either to CBTI or sham insomnia therapy. The Hamilton Rating Scale for Depression (HAMD-17) and Insomnia Severity Index were administered at baseline and then bi-weekly during treatment to determine depression and insomnia remission.

The study was part of a larger research project for which Edinger was co-investigator along with co-investigators Daniel Buysse, MD, from the University of Pittsburgh; Andy Krystal, MD, from Duke University and the University of California, San Francisco; and lead principal investigator Rachel Manber, PhD, professor of psychiatry and behavioral sciences at the Stanford University Medical Center.

"Our findings highlight the importance of adequate objective sleep in the recovery from depression and insomnia," said Manber. "The data suggest that short sleep duration may be a risk for refractory depression."