I learned a few things in reading that article. First I had never heard of a "sham CPAP", but concluded it is a CPAP modified so it delivers no therapy even though the user may think it is. Second, I have never heard the claim that CPAP is any benefit in losing weight. The final paragraph in the report seems to sum it all up.
"In conclusion, treatment of OSA with CPAP may result in modest weight gain. Thus, if overweight, OSA patients should be encouraged to lose weight by other modalities and not rely on any direct physiologic effect of CPAP."
I find it odd that anyone would think a CPAP would help them lose weight. The cause of apnea is related to being over weight in almost all cases. But, because you treat the apnea, there is no reason to think it will help you lose weight.
I guess I have always had low expectations of the benefits from using a CPAP. The sleep technician tried to tell me that it would cure my diabetes, and I could barely keep from laughing right in her office. It is kind of similar to the weight gain thing. Yes, being overweight can cause diabetes. Yes, being overweight can cause apnea. But, it does not follow that if you treat the apnea you will reverse the diabetes. Apnea does not cause diabetes. Diabetes does not cause apnea. But, they both can be caused by being overweight. Coincidental does not mean causality.
I suspect the same conclusion could be made about blood pressure. Increased weight increases your blood pressure. Increased weight causes apnea. But, that does not mean apnea causes high blood pressure and there should be no expectation that treating apnea would lower you blood pressure. Losing weight almost always will though.
My expectations out of CPAP treatment are simple. I expect it to keep me from snoring and keeping my wife awake. I expect it to possibly improve the quality of my sleep. That is about it. I do not expect it to lengthen the time I sleep, just improve the quality.
