We know that people with chronic health problems often experience depression or anxiety associated with their condition, but the link with sleep apnea is stronger than usual. Mood disorders are common in people with sleep apnea, and depression is so commonly linked that it often masks the underlying problem of sleep apnea.
We aren’t yet able to say that sleep apnea causes depression or anxiety, but we are able to ask the related question: if we treat sleep apnea, will depression and anxiety improve? A new study published in the journal eClinicalMedicine, published by The Lancet, shows that yes, treating sleep apnea can significantly improve depression.
Analyzing Old data
For this study, researchers looked at data from over 2400 patients in the SAVE study (Sleep Apnea cardioVascular Endpoints). These patients had moderate to severe sleep apnea and some type of cardiovascular disease. The patients were followed for an average of 3.7 years and treated with CPAP.
When researchers looked at depression, they found that treatment reduced depression symptoms, whether or not they saw reductions in daytime sleepiness. In fact, the NNT (number needed to treat–how many patients need to be treated with CPAP to prevent a bad outcome) is only 15, comparable to some antidepressant drugs. This confirms the results of an earlier meta-analysis. However, there was no measurable improvement in anxiety symptoms.
Researchers supported their finding in this study with a review of other studies showing that CPAP could reduce symptoms of depression. They highlighted that this is more than just a gain from the standpoint of depression: reducing depression symptoms could improve the survival rate from cardiovascular problems. In addition, CPAP has the benefit of not introducing additional risk of side effects as antidepressants do.
Adherence to CPAP Is a Problem
However, this study isn’t all good for the ability of CPAP to help people with depression. It highlights one of the biggest limiting factors of CPAP: compliance (or adherence, as they say in this study). Although CPAP is a very effective treatment for sleep apnea (and, as it turns out, depression), it isn’t actually as effective as it could be. That’s because many people find it hard to stick with their CPAP treatment.
In this study, less than half of the people assigned to use CPAP actually stuck to the treatment for the duration of the study. In addition to the other risks of sleep apnea, it seems that we shouldn’t allow more than half of the population to continue suffering with a condition when an effective alternative exists.
If Adherence Is a Problem for You
If you are one of the many people who have been prescribed CPAP in the Denver area but can’t stick to the treatment protocol, don’t despair. Oral appliance therapy is an alternative that may be just as effective, and it’s also much more comfortable and convenient, leading to much higher compliance rates (over 90% when measured by the CPAP standard).