Researchers found "novel links" between sleep duration and depression.
"Healthy sleep is a necessity for physical, mental and emotional well-being," American Academy of Sleep Medicine President Dr. M. Safwan Badr, said in a news release. "This new research emphasizes that we can make an investment in our health by prioritizing sleep."
A research team looked at 1,788 adult twins and found sleep outside of normal durations could increase the genetic risk of depression.
Twins that slept between seven to 8.9 hours per night had a 27 percent heritability of depressive symptoms; this genetic influence rose to 53 percent five hours per night and was at 49 percent in those who got 10 hours.
"We were surprised that the heritability of depressive symptoms in twins with very short sleep was nearly twice the heritability in twins sleeping normal amounts of time," principal investigator Doctor Nathaniel Watson, associate professor of neurology and co-director of the University of Washington Medicine Sleep Center said in the news release. "Both short and excessively long sleep durations appear to activate genes related to depressive symptoms."
The study suggests controlling sleep could help in depression treatment.
A past study that looked at 4,175 subjects between the ages of 11 and 17 first documented the link between depression and sleep duration.
"Results suggest sleeping six hours or less per night increases the risk for major depression, which in turn increases the risk for decreased sleep among adolescents," the news release reported.
"These results are important because they suggest that sleep deprivation may be a precursor for major depression in adolescents, occurring before other symptoms of major depression and additional mood disorders," principal investigator Doctor Robert E. Roberts, professor of behavioral sciences in the School of Public Health at the University of Texas Health Science Center , said in the news release. "Questions on sleep disturbance and hours of sleep should be part of the medical history of adolescents to ascertain risk."
