A new study examined the rate of obstructive sleep apnea in people with major depressive disorder and insomnia.

The study involved 51 people with both depression and insomnia; they were evaluated by an overnight sleep study.

Results show a high rate of OSA in people with depression and insomnia; 39 percent of the people had an apnea-hypopnea index (AHI) of 15 or more breathing pauses per hour of sleep. An AHI of 15 to 30 is considered “moderate” sleep apnea.

Men were more likely than women to have OSA. People with sleep apnea also were older and had a higher body mass index (BMI).

Previous studies also have linked sleep apnea to depression.

A 2008 study in the Journal of Clinical Sleep Medicine involved 1,106 adults with sleep apnea. About 19 percent of the men and 37 percent of the women had depression.

A 2006 study involved 788 men and 620 women. Results show that people with mild sleep apnea were two times more likely to have depression than people without OSA. The risk of depression was even higher in people with moderate or severe sleep apnea.

The good news is that treating sleep apnea can reduce the symptoms of depression.

A 2007 study in the Journal of Clinical Sleep Medicine examined the effects of CPAP therapy on depression. The AASM recommends CPAP as the treatment of choice for people with sleep apnea.

The study involved 50 adults with severe sleep apnea. Four to six weeks of CPAP therapy lowered depression symptoms in 94 percent of the group.

This improvement was long lasting; after one year of CPAP therapy, 88 percent of the group still had lower symptoms of depression.

Get help for sleep apnea at an AASM-accredited sleep center near you. Learn more about the link between sleep apnea and depression on SleepEducation.com.