Abstract
Posttraumatic stress disorder (PTSD) is associated with activation of the brain fear circuitry. Studies of sleep in PTSD provide a unique window into the relation or connection of sleep physiology and autonomic activation. Serial level 3 home sleep apnea tests (HSATs) (10 HSATs over 1 month) in a patient who was medication free, had PTSD, and had refused positive airway pressure therapy, revealed both percentage of rapid eye movement (REM) sleep (mean ± standard deviation [SD]: 19.88% ± 10.11%; range 1.94% to 35.01%) and REM sleep duration (minutes) (mean ± SD: 73.08 ± 48.24; range 3.49- 151.59) varied markedly over the 10 HSATs. Both percentage of REM sleep and REM sleep duration correlated negatively with sleep onset latency (r = -.661, P = .037 and r = -.748, P = .013, respectively) and the mean pulse rate during sleep (r = -.667, P = .035 and r = -.771, P = .009, respectively), and positively with sleep efficiency (r = .824, P = .003 and r = .922, P < .001, respectively) and percentage of stage N3 sleep (r = .784, P = .007 and r = .734, P = .016, respectively), an index of parasympathetic tone during sleep. These empirical findings suggest a previously unreported inverse relation of REM sleep with sleep fragmentation and sympathetic activation.