We know that depression and sleep apnea go hand in hand. That’s why it’s a surprise that a new study finds a relatively low incidence of obstructive sleep apnea in the population. However, the design of the study likely accounts for the underestimation.
The Study and Its Findings
For this new study, researchers looked at the population of a sleep clinic, which contained the records of over 3500 patients given sleep studies from 2002-2014. Of these patients, the study focused on 703 individuals that had symptoms of major depression.
They then looked back at the records and separated the subjects into those that had sleep apnea with an apnea-hypopnea index (AHI) of 15 or greater, and those that didn’t. By this criterion, about 14% of patients with major depression had sleep apnea. The risk of sleep apnea was found to be highest among men who were over the age of 50, were obese, and who had metabolic syndrome. These are all recognized risk factors for sleep apnea generally, so there’s no surprise that they’re associated with sleep apnea in major depression.
The biggest surprise is the relatively low rate of sleep apnea found in this population. However, there are several reasons why the study likely underestimates the true rate of sleep apnea in the population of people with depression.
Limitations in the Study Design
There are several significant problems in the design of this study. However, the most serious problem is that it’s a retrospective study. It can only work with data that’s already been assembled. There’s no way to check it or verify it: it just has to be taken as it is.
Another problem is that the study only considers people who have already been sent to get a sleep test. However, other studies of persons with mental health conditions have complained that this population isn’t properly screened for sleep apnea. So few people with major depression are sent for sleep studies in the first place. This means that the population is unlikely to be representative. It’s possible that the study is high, but, on the basis of previous estimates, it’s more likely that it’s low.
Also, the study uses a relatively high threshold for sleep apnea. They only count sleep apnea cases that are moderate to severe. There is certainly value in gauging this population, but even mild sleep apnea can have serious health effects, and may contribute to mental health conditions such as major depression.
Diagnosed with Depression? Get Screened for Sleep Apnea
Sleep apnea is a serious health condition, and it’s often found in people with major depression and other psychiatric conditions. The presence of sleep apnea can make it harder to treat your depression, and will likely increase your risk of other serious health conditions. But treatment of sleep apnea reduces depression symptoms.
If you want to learn more about the overlap between sleep apnea and mental health conditions in Omaha, please call (402) 493-4175 today for an appointment with a sleep dentist at the Advanced Dental Sleep Treatment Center.