A patient-based study led by Luciano Drager, MD, at the University of Sao Paolo, Brazil, provides insight into the correlation between obstructive sleep apnea and lipid metabolism—and how CPAP treatment may be beneficial for more than just the lungs. The findings are published in the Journal of Lipid Research.

In this study, men with sleep apnea were found to have slower breakdown of triglyceride-rich lipoproteins and reduced clearance of their metabolites from the plasma compared with men without the disease who were the same age and weight. After three months of CPAP treatment, the same patients showed significantly improved plasma lipid clearance.

The difference in lipid clearance may predispose patients with untreated sleep apnea to atherosclerosis, a thickening of the arteries that can lead to heart disease. Indeed, patients in the study tended to have thicker deposits in their carotid arteries. Sleep apnea can lead to many cardiovascular complications, including stroke, and this study provides a possible mechanism.

A caveat to this study is that the number of patients was small, just 15 individuals, and all were men with severe apnea. However, if the results can be replicated in a larger and more diverse set of patients, people with sleep apnea will have one more reason to slip on the CPAP mask.