i have done 20yrs of rotating shift work(18yrs old when started), 13yrs prior to cfs. I never realised, thats 7 years with cfs. The last few years working day and afternoon shifts, no nights. I have had a few short breaks during this time and a 6-9month break 3-4 yrs after cfs onset. I have had many sick days from work purely out of lack of sleep.
I think its played a part in buggering my sleep up(here i am at 3am typing this). I cant say i have a definite pattern other then i feel better in the afternoons and early part of night. I do think alot is a cfs thing which makes it harder for the body to bounce back to a normal routine. I use sleep meds to fit into a routine for work as well as just generally needing sleep. I feel that if i didnt use sleep meds that my body clock would have me sleep between 3-5am to 9-11am.
My thoughts for my situation are that the shift work has made my sleep worse but then i have met alot of people here with funky sleep patterns like mine and never done shift work. The hypothalamus in the brain controls alot of important functions such as sleep, hormones etc, i think for many of us with sleep/insomnia etc, this part of the brain has been damaged due to the cfs/me/infections ??
Another thing i almost forgot. The last few years i have done the odd night shift which i have managed to get through ok but trying to recover from them has been extremly hard, unable to sleep(during the day) much at all after being awake all night, well over 24hrs. It has taken me several days to get back to my normal. If i was forced to work nights again i think that would be the end of me???