Clinical depression is a major health problem, affecting an estimated 300 million people worldwide. Here in the United States, experts suggest that approximately 9 percent of adults suffer from depression, or major depressive disorder. Though it can manifest in many forms, depression often appears as exhaustion, feelings of hopelessness or sadness, withdrawal from daily activities, and many other symptoms that can get in the way of daily life.
But now, a new study by the Department of Psychiatry and Health Behavior at Medical College of Georgia at Augusta University is linking depression to another condition that could cause similar symptoms: obstructive sleep apnea.
Obstructive sleep apnea, or OSA, is a condition that affects millions of Americans each year. Because it occurs during sleep, however, exact numbers are not known. But with 22 million diagnosed cases of some sort of sleep apnea and what experts estimate is another 80 percent of cases undiagnosed, OSA is also a major health crisis facing our nation.
Now, according to the study, which was published in the Journal of Psychiatric Research is suggesting the two conditions could very possibly be linked.
"Researchers in the study found that treatment-resistant depression could be caused by obstructive sleep apnea," says Dr. Kelley Mingus, a dentist who treats sleep apnea in his Bend, Oregon, practice.
How so? Well, while the exact link is not known, researchers point to similar symptoms in both groups. Furthermore, according to the study, persons with obstructive sleep apnea don’t respond well to antidepressants, something that could be responsible for their treatment-resistant depression.
"According to recent statistics, upwards of 50 percent of people with major depressive disorder do not benefit from current drug therapies," says Mingus. "And that could be because they have obstructive sleep apnea."
The study originally sought to find a link between depression and insomnia, but researchers noticed that many of the respondents (a full 14 percent) had obstructive sleep apnea.
"What’s interesting to note about the people who had obstructive sleep apnea is that many of them were women, and many of them were not obese, which while it's not a requirement to have obstructive sleep apnea, it occurs very frequently in obese patients," Mingus says. "It’s rare to see it in this many patients with a healthy BMI."
Mingus echoes what the study authors concluded in the study - that screening depressed patients for sleep apnea, especially those who are resistant to treatment, could save a lot of time, money and frustration.
"If we can screen for sleep apnea at the beginning, we can possibly eliminate a lot of costly, painful and lengthy tests that may not even be necessary," says Mingus. "But better yet, we may be able to more effectively treat the depression and the sleep apnea simultaneously."