Depression can be debilitating and researchers continue to explore more effective methods for treating this disease.
A recently published study (Rethorst, et al.) examined the biological links between sleep and depression, and identified a treatment that is effective for “resetting” the negative feedback loop of depression and sleep disturbance.
Examining the role of sleep disturbance in depression is complicated because some people with depression over sleep, while others can’t fall asleep or stay asleep. These opposite manifestations of sleep disturbance are associated with the subtype of depression a person is struggling with.
All depression is defined by sad mood or lack of enjoyment; beyond that:
- Melancholic Depression is characterized by difficulty falling or staying asleep (insomnia) and decreased appetite, along with an inability to feel happy even when something good happens.
- Atypical Depression is characterized by excessive sleep (hypersomnia) and increased appetite, but an ability to temporarily experience an improvement in mood in response to something good.
Disrupted sleep is a symptom of depression and sleep is involved in a negative feedback loop with depression–as either sleep or depression worsens, the other symptom (depressed mood or sleep) worsens.
On the other hand, improving sleep improves depression.
To summarize the complex results of the Rethorst, et al. study:
There was an association between changes in certain biomarkers (inflammatory cytokines and brain-derived neurotrophic factor) and improvement in sleep for those with hypersomnia (atypical depression), but not for those with insomnia (melancholic depression). Nonetheless, those with insomnia showed an improvement in sleep and depression as a result of the treatment.
This supports the hypothesis that the biological underpinnings are different for those with atypical vs melancholic depression.
Why is this important?
This research furthers the understanding of the relationship between sleep, inflammation, and depression, and the negative feedback loop that worsens a depressive episode.
Even more important is the treatment used in this study. This treatment was effective in resetting the negative feedback loop for both those with hypersomnia (atypical depression), and insomnia (melancholic depression), even though the biological underpinnings of these subtypes of depression are different.
What is the magic pill?
The subjects in the treatment group participated in two “doses” of aerobic exercise per week for 12 weeks. The two “doses” equalled 150 minutes of moderate intensity exercise per week.
In addition to the changes in biomarkers found in this study, exercise is known to improve functioning of the hypothalamic-pituitary axis, which improves sleep.
Dr. Trivedi, a world-renowned researcher in the field of depression, discusses the results of this study here, and talks about the use of exercise as an effective treatment for depression.
For more information about Dr. Ware’s psychological practice, click here.