New studies suggest that obstructive sleep apnea (OSA) may have a strong influence on antidepressant response and increase the risk for mild cognitive impairment in older patients with major depressive disorder (MDD). According to a Medscape news report, the first study was an open-label trial involving more than 400 patients with MDD. The study showed that individuals with comorbid OSA were 1.5 times less likely to respond to 12 weeks of treatment with the antidepressant drug venlafaxine than those without OSA.

Study participants with both MDD and OSA also reported longer episodes and more severe depression, lower quality-of-life scores, and decreased physical functioning. Lead author Lauren Waterman says, “This shows that clinicians should definitely screen for sleep apnea when patients are presenting with late-life depression.”

Researchers for the second study examined data on 25 patients with MDD and cognitive impairment, and all participated in a 16-week antidepressant study that screened for possible OSA. The study revealed that patients with MDD and a high probability of OSA had considerably lower cognitive performance than those with moderate to low probability of OSA.

Iqbal Ahmed, MD, explains, “Both studies show that it’s not a good thing to have sleep apnea. One showed that it may influence response to antidepressants, and the other that it may block improvement in cognition ? even if there is some improvement in mood.”

Ahmed adds, “The first study showed less antidepressant response in those with sleep apnea. The second paper said you may get some response, but it’s not very robust. And although there might be improvement in mood, you don’t get improvement in cognition. The take-away is that you need to not just treat the depression. It’s important to assess patients at high risk for sleep apnea, especially in those with unresponsive depression.”

Both studies were presented at the American Association for Geriatric Psychiatry (AAGP) 2015 Annual Meeting.

Source: Medscape