https://forums.cpap.co.uk/ Need help regarding your (possible) sleep apnea? Discuss here with fellow apnea patients. Also the place to discuss the various types like central and obstructive sleep apnea. en Fri, 26 Jun 2026 18:42:05 GMT vBulletin 60 images/misc/rss.png https://forums.cpap.co.uk/ https://forums.cpap.co.uk/forum/sleep-apnea/sleep-studies/40688-cpap-machine-and-sleep-study-accuracy-when-measuring-ahi Tue, 23 Jun 2026 15:30:10 GMT Hello. I was diagnosed with moderate OSA after a sleep study in which I scored 16.2 AHI with a high Epworth score. I was put on CPAP which I found... I was diagnosed with moderate OSA after a sleep study in which I scored 16.2 AHI with a high Epworth score. I was put on CPAP which I found intolerable but persisted with in order to be considered compliant with regards to the DVLA and driving.

After 3 months on CPAP my AHI level was averaging at 8, and in subsequent months it lowered further and fluctuated between 3 and 10.

In the meantime I had lost a significant amount of weight (15% of my body weight) and was well within the normal BMI range so I persuaded the hospital to conduct another sleep study. I had a 5 day run-up (washout) not using the CPAP machine before the study, as instructed by the consultant. The results of this test were an AHI of just 4.2 so I have been discharged by the clinic and am now deemed not to have OSA so no longer use the CPAP.

My question is: if when using the CPAP machine I was registering up to 10, how could I register below 5 without the machine??
In other words, how accurate are these sleep tests and also how accurate are the CPAP machines? It is worth noting that I struggled so much with the CPAP that I spent many hours in the night just lying in bed very self-consciously breathing with the mask on. Also I found the whole thing so very distressing and uncomfortable that I spent quite a bit of time sobbing. Perhaps this skewed the results?

Many thanks.]]> Sleep Studies Lulabelle https://forums.cpap.co.uk/forum/sleep-apnea/sleep-studies/40688-cpap-machine-and-sleep-study-accuracy-when-measuring-ahi