I went through a sleep study, pulmonary tests, heart tests, etc. My sleep study showed low oxygen saturation levels while sleeping. No sleep apnea. After all the results were in, my Pulmonologist said that the supposed culprit was the clonazepam I was taking at night. It was causing shallow breathing. Since I have been on clonazepam for 20 years, he said the withdrawal wouldn't be worth it. I now use supplemental oxygen at night and my levels at night are now normal. I still wake up 3 times a night though. The Doctor said they see a lot of Bipolar people with insomnia. Is it our meds? Hmmm...