I was diagnosed with Generalized Anxiety Disorder and Chronic Panic Disorder in addition to a myriad of other little things like not being able to concentrate, high blood pressure, and getting sick a lot. For years my doctor couldn't figure out what was causing the problems. I'm not overweight, I don't smoke, drink or do drugs, I'm in good shape and exercise a lot. My diet is pretty good and I got 7-8 hours of sleep every night.
It was a shot in the dark to do the sleep study to test me for sleep apnea, since I didn't have any symptoms other than some occasional snoring. But the sleep study revealed that I had an Apnea Hypopnea Index of 70. A second sleep study came back with an AHI of 84. I had severe sleep apnea, but never knew it.
Once I got on the CPAP machine, my anxiety dropped to nearly nothing, and I haven't had a single panic attack. I haven't been sick in months, my BP is back to normal without drugs, and my daily work performance has increased dramatically. I feel great, and without a lucky guess by my doc I'd still be living in the fog that I didn't even realize was there.
It's amazing how much difference a good night's sleep can make.