Early this month, we discussed how sleep apnea could lead to behavioral problems in children. A new depression and sleep problems study indicates that sleep apnea may also have a similar effect on the mental health and wellness of adults by increasing their risk of depression.

Additional health problems include elevated blood pressure, heart attach, stroke, heart failure, irregular beating of the heart, diabetes, worsening of ADHD, and poor cognitive function.

Sleep apnea can be defined as shallow or paused breathing during sleep. Typical treatments for individuals suffering from sleep apnea range from minor lifestyle changes to oral devices and even surgery depending on the severity of the case, according to the Mayo Clinic.

Common risk factors that are associated with individuals suffering from sleep apnea include being overweight, being over the age of 40, having a larger than average neck size, large tonsils and/or large tongue, a small jaw bone, a family history of sleep apnea, Gastroesophageal or acid reflux, or some form of nasal obstruction due to a deviated septum, allergies, or sinus problems.

Depression Risk Increase of 5.2x for Women and 2.4x for Men

During the depression and sleep problems study, researchers from the Centers for Disease Control and Prevention analyzed the health data of nearly 10,000 adults involved in the National Health and Nutrition Examination Survey, an ongoing CDC study. The participants were asked to answer questionnaires detailing their frequency of depression symptoms, allowing the researchers to determine which of the participants were depressed. In other words, the participants considered to be depressed by the researchers had not necessarily received diagnoses of clinical depression.

A total of 3% of the female participants and 6% of the male participants had been diagnosed with sleep apnea. After aggregating all of the data, the researchers determined that women with sleep apnea were 5.2 times more likely to experience depression than women without sleep apnea. Interestingly, men with sleep apnea were less susceptible to depression than women with sleep apnea, but still 2.4 times more likely to experience depression than their normal-sleeping counterparts.

The researchers also noticed an increased depression risk in subjects with sleep breathing problems aside from sleep apnea, though snoring was not linked to any change in depression risk.

Caveats of the Study

The CDC study carried certain limitations, meaning that future research will be needed to confirm the link between sleep apnea and increased depression risk. The limitations were as follows:

• Symptoms of depression were self-reported, and did not rely on a medical diagnosis

• The participants reported their sleep problems and depression symptoms only once

• A given participant may have sleep breathing problems without being aware of it

• The researchers did not distinguish between individuals that were being treated for depression and those that were not

Still, the researchers found such a marked risk increase that the findings are worth noting, especially for those who experience both sleep apnea and depression.

Exploring the Link Between Sleep Apnea and Depression

According to CDC epidemiologist Anne Wheaton, sleep breathing problems such as “snorting, gasping [and] stopped breathing” were associated with a number of common depression symptoms, such as the persistent feelings of failure and hopelessness. Although Wheaton and the other researchers didn’t expect to find this link, they did expect subjects with sleep apnea to report other signs of depression, such as feeling tired and low-energy, and sleeping too much or too little.

Based on their findings and the fact that sleep apnea and depression are both underdiagnosed, the researchers believe that screening individuals with sleep apnea for depression (and vice versa) may be appropriate.

Despite the aforementioned limitations of the study, the researchers are confident in their findings since other studies have reached similar conclusions. In one study, subjects who were treated for sleep apnea saw their depression symptoms improve. Another study found that the odds of developing eventual depression were partially dependent on the severity of sleep apnea symptoms.

The researchers were also confident in their findings because they accounted for weight, sex, age and other factors that could potentially influence the results.

So far, the logic behind the link is uncertain. However, the researchers suggested that sleep apnea and other sleep breathing problems could result in fragmented sleep and/or low blood-oxygen levels during sleep, subsequently increasing the risk of depression.

“When a person stops breathing like this, they are momentarily brought out of deeper levels of sleep. They may not fully wake up, but they will not get the proper amount of rest,” said Wheaton.

Sleep Breathing Problems: The Bottom Line

A recent study conducted by the CDC indicates that sleep apnea and other breathing problems that occur during sleep may increase the risk of developing depression. The risk was about twice as great for women as it was for men. Future research will be needed to confirm the link, as well as the scientific reasoning behind it.

The full text of the CDC sleep apnea and depression study can be found in the medical journal Sleep.