A study in the Feb. 15 issue of the Journal of Clinical Sleep Medicine shows that one-fifth of multiple sclerosis patients surveyed in a large tertiary MS practice had been diagnosed with obstructive sleep apnea, and more than half were found to have an elevated risk for OSA based on a validated screening tool. Further analysis showed that OSA risk was a significant predictor of fatigue severity, even after adjusting for potential confounders. The results suggest that OSA may be a contributor to fatigue, which is one of the most common and debilitating symptoms of MS.