I generally counsel patients that good quality sleep is needed to more effectively lose weight. Conversely, poor sleep promotes weight gain. So you would think that starting CPAP for obstructive sleep apnea would help you to lose weight. A recent study published in the Journal of Clinical Sleep Medicine found that this was not the case. In fact, using CPAP was found to cause statistically significant mild weight gain compared to sham CPAP users in this prospective randomized study. The active CPAP users gained about 3/4 of a pound over 6 months, where the sham CPAP users lost about 1.5 pounds.
This study only adds to the conflicting results on CPAP use and weight status. There are a number of possible reasons why this can happen, but no one is absolutely sure. In fact, I’ve been disappointed myself that not not too many people can lose weight on CPAP. I had one patient who actually gained weight after a tracheotomy. Of course, I’ve also had many patients who did lose significant weight after CPAP, which only adds to the confusion.
This particular study only showed weight gain with CPAP use. So far, there are no such studies showing similar results with dental appliances or surgery. Like what most scientific studies end with, more studies are needed.