Major depression with insomnia increased active rapid eye movement (REM) sleep and severe daytime function, a new study found. The study compared primary insomnia to the insomnia occurring in major depression and general anxiety disorder (GAD). Researchers found:
- Major depression with insomnia exhibited higher daytime dysfunction than primary insomnia, showed significantly higher values of REM periods, time of REM sleep and percentage of REM state, and presented lower percentage of non-REM compared with primary insomnia and GAD with insomnia.
- GAD with insomnia showed lower awakening number than primary insomnia.
- Major depression with insomnia and primary insomnia may be categorically different.
Sun Q, et al. Comparing primary insomnia to the insomnia occurring in major depression and general anxiety disorder. [Published online ahead of print August 9, 2019]. Psychiatry Res. doi:10.1016/j.psychres.2019.112514.
Insomnia is a standalone DSM Disorder but is also common within the DSM-5. Insomnia may be found in mood, anxiety and other disorders as a key and manifest symptom. Here, depression-induced insomnia and anxiety-induced insomnia had similar subjective poor sleep quality and difficulty falling asleep as to those with primary insomnia without other psychiatric characteristics. Objective sleep studies also showed that depressed patients had high amounts of REM sleep, lower non-REM sleep and less awakenings than insomnia only patients but had the greatest daytime dysfunction as a result. Anxious patients only had lower awakenings compared to primary insomnia. Interestingly, all patients felt the same poor sleep quality, but the most objective sleep study measures did show differences suggesting that insomnia is a characteristic that may look similar phenotypically across differing psychiatric disorders, but electrophysiologically may be different from a brain functioning perspective. Perhaps investigating the use of polysomnographic sleep studies for both differential diagnostic and full remission outcome measuring is further warranted? —Thomas L. Schwartz, MD; Senior Associate Dean of Education, Interim Chair/Professor of Psychiatry, SUNY Upstate Medical University.