Description

The co-existence of traumatic brain injury, post-traumatic stress disorder (PTSD), and chronic pain defines the clinical entity referred to as the "polytrauma clinical triad" (PCT). Well recognized to be highly prevalent and disabling in US military service members and Veterans, those with the PCT are traditionally viewed as the most disabled cases and most refractory to conventional therapies. Central to the challenge in effectively treating Veterans with the PCT is the bi-directional, mutually reinforcing relationship between these conditions. Further complicating is the influence of sleep and cognitive impairment, both of which are widely regarded as primary contributing chronic sequela associated with the PCT. The specific contribution from sleep in exacerbating this clinical picture is supported by extensive scientific precedent demonstrating impairments in sleep intensify and worsen these related sequela (e.g., cognitive impairment, pain management, and PTSD symptom severity), which in turn, contribute to further impairment in sleep. Accordingly, an effective intervention targeting sleep may alleviate rehabilitative pressure on these associated sequelae and facilitate breaking out of this vicious cycle (i.e., poor sleep exacerbating outcomes, and in turn, further impairing sleep).

Recent work from the investigators' laboratory demonstrate promise for a simple, at home, non-pharmacologic and cost-effective, sleep focused intervention: morning bright light therapy (MBLT). The investigators have demonstrated robust feasibility, acceptability, and limited efficacy for MBLT to improve sleep, and thereby, improve cognitive function, PCT symptom management and overall quality of life in this medically complex and vulnerable population. Accordingly, this proposal aims to extend the foundational work from the CDA-2 to inform a prospective phase II placebo-controlled randomized clinical trial examining effectiveness for MBLT as a sleep- based intervention in Veterans with the PCT.

Specific aims designed to test this hypothesis are to determine effectiveness for MBLT to improve 1) sleep, 2) cognition, and 3) PCT symptom management in Veterans with the PCT. The investigators propose to enroll n=138 Veterans, randomized 2:1 to MBLT (10,000 lux light exposure for 60 min within 120 min of waking for 4-weeks) or a no- light sham-MBLT condition (as previously published using the same duration/timing). Sleep, cognition and PCT symptom management will be assessed through a novel combination of subjective/self-report, objective measures, and ecological momentary assessment sampling. Specific objective assessments include wrist- based actigraphy and as exploratory outcome in a sub-set of participants, home-based overnight polysomnography. Outcomes will be assessed pre- and post-intervention, with follow-up at 6- and 12-weeks post-intervention.

It is expected the proposed work will demonstrate effectiveness for MBLT to improve sleep, cognition, and PCT symptom management including ameliorating chronic pain and improving quality of life, in Veterans with the PCT. This project will demonstrate, 1) an effective treatment option, alone or in combination with existing rehabilitative efforts, in Veterans with the PCT, and 2) sleep-wake disturbances may be implicated in the pathogenesis of these functional impairments, thereby establishing greater precedent for targeting sleep as a meaningful primary and/or adjunctive rehabilitative therapy.