Joel Yager, MD reviewing Cho HJ et al. Transl Psychiatry 2016 Mar 8.

In an experimental study, disturbed sleep plus inflammation provoked depressed symptoms in women more than men.

Both sleep disturbance and inflammatory conditions have been linked to depression susceptibility. To study the potential interactions between these two factors, researchers enrolled 111 healthy university students (67 women) who were assessed for self-reported sleep quality during the prior month and for current depressed mood. Participants were randomized to injections of placebo or Escherichia coli endotoxin at doses sufficient to raise levels of interleukin (IL)-6 tenfold and tumor necrosis factor α (TNF-α) fivefold (comparable to increases seen in HIV infection and rheumatoid arthritis); inflammatory cytokine levels and mood ratings were evaluated hourly for 6 hours.

Baseline scores on a depressive-symptoms inventory were modestly higher among disturbed sleepers. Following endotoxin injection, all subjects exhibited comparably increased levels of both IL-6 and TNF-α. In analyses adjusted for age, race, body-mass index, and baseline depression scores, women compared with men experienced robust increases in depressed mood after endotoxin; men showed no increase in depressed mood following endotoxin injection. Furthermore, women with disturbed sleep showed substantially greater escalations in depressed mood compared with those without sleep disturbance (even after adjustment for concurrent ratings of physical symptoms such as headache, muscle pain, shivering, and nausea) — and correlations between depressed mood and cytokine elevations were twice as strong in sleep-disturbed women.

Citation(s):

Cho HJ et al. Preexisting mild sleep disturbance as a vulnerability factor for inflammation-induced depressed mood: A human experimental study. Transl Psychiatry 2016 Mar 8; 6:e750.

JWatch