Clinical effectiveness of a group therapy combining cognitive behavioural therapy for insomnia and imagery rehearsal therapy for nightmares in an operational stress injury clinic.

STUDY

OBJECTIVES

This study evaluated the effectiveness of a group intervention combining cognitive behavioural therapy for insomnia (CBT-I) and imagery rehearsal therapy (IRT) for nightmares, delivered to current and former military and law-enforcement personnel with post-traumatic stress disorder (PTSD) at an outpatient operational stress injury clinic. This study further investigated the interrelationships among changes in insomnia, nightmares and PTSD symptoms during treatment.

METHODS

Sixty outpatients (78% male, 50.7 ± 7.3 years) attended 10 weekly 2-h sessions of CBT-I/IRT and completed daily sleep diaries as well as pre-/post-intervention questionnaires assessing the severity of insomnia, nightmares, and PTSD, sleep-related beliefs, ruminations, and life satisfaction.

RESULTS

From baseline to post-intervention, significant reductions were observed in insomnia severity, nightmare distress and frequency, PTSD severity, dysfunctional beliefs about sleep, and insomnia-related ruminations, while life satisfaction increased (all p < .05). Sleep-diary indices improved following CBT-I/IRT, including shorter sleep onset latency (t(37) = 5.0, p = ≤.001), longer total sleep time (t(37) = -1.7, p = .049), less wake after sleep onset (t(37) = 1.8, p = .037), and higher sleep efficiency (t(37) = -5.1, p ≤ .001). A positive correlation was identified between the degree of improvements in insomnia severity and nightmare distress (r(46) = .41, p = .004). Improvements in insomnia severity (r(48) = .35, p = .013) and in nightmare distress (r(46) = .36, p = .012) both correlated with improvements in PTSD.

CONCLUSIONS

This study supports the real-world effectiveness of CBT-I/IRT for addressing sleep disturbances, trauma-related symptoms, sleep-related cognitions and life satisfaction in people with PTSD. The multidimensional symptom improvements highlight the value of jointly addressing insomnia and nightmares in trauma-exposed populations and support wider implementation of CBT-I/IRT among service members.