I think that anything that increases stress or overall fragility is likely to increase the likelihood of flashbacks, nightmares etc, and fatigue due to lack of sleep or poor quality sleep would certainly fit into this category.
I know that MS said that she hadn't had any particular sleep disturbance prior to these incidents, but the relationship between fatigue and flashbacks (or other such intrusive symptoms) is a bit of a chicken and egg one I think, in that the unnaturally intense mental experience of a flashback is very tiring as well. In this way I think that one can lead to the other and in many cases, the cause may well be indistinguishable from the consequence.
Just my thoughts, as someone who seems to experience it this way.
Maddog
I know that MS said that she hadn't had any particular sleep disturbance prior to these incidents, but the relationship between fatigue and flashbacks (or other such intrusive symptoms) is a bit of a chicken and egg one I think, in that the unnaturally intense mental experience of a flashback is very tiring as well. In this way I think that one can lead to the other and in many cases, the cause may well be indistinguishable from the consequence.
Just my thoughts, as someone who seems to experience it this way.
Maddog