Obstructive sleep apnea (OSA) patients with symptoms of excessive sleepiness have the greatest risk of depression, says a new study, and should be screened for this condition.

Dr. Stacey Ishman and a team of researchers at Johns Hopkins University evaluated 56 consecutive patients with OSA aged 27-74 who visited a clinic for treatment and compared them with 51 patients who did not have OSA.

Overall, significantly more OSA patients met the criteria for depression (29%) than those who did not have OSA (8%). The severity of their sleep apnea was a good predictor of the severity of their depression symptoms, however, their depression symptoms did not predict the severity of the sleep apnea.

The patients’ scores on a scale measuring the severity of their depression symptoms correlated with the scores on a sleepiness scale as well, but their sleepiness scores did not correlate with the severity of their sleep apnea. However, previous studies indicate that patients with severe OSA do not necessarily report subjective sleepiness, noted Dr. Ishman.

The results were limited by the small sample size and the overlap between OSA and depressive symptoms, said Ishman, but they do suggest that OSA patients with excessive sleepiness may in particular benefit from being screened for depression.

Their findings were presented at the Triological Society Combined Sections Meeting.

By Nancy Schimelpfening,
About.com Guide to Depression