I have sleep apnea, had a sleep study done in 2000. I use a cpap machine for this. I would not want to live without it.
It is my belief, there is a cross section of a sort, with PTSD and sleep disturbances. I think poor quality sleep might tend to perpetuate the chemical / neurological imbalance, that people with PTSD already have. Good sleep is not going to cure PTSD, but it is helpfull.
I think it would be invaluable for you, and others who have similar experience, to go and have a sleep study.