Insomnia and Chronic Pain Mediate the Relationship Between Traumatic Brain Injury and Reduced Positive Airway Pressure Adherence Among Veterans.

Abstract

Objective: To examine whether co-morbid insomnia, post-traumatic stress disorder (PTSD), depression, and chronic pain mediate the relationship between traumatic brain injury (TBI) and positive airway pressure (PAP) treatment adherence.

Setting: One Veterans Health Administration (VHA) sleep medicine site.

Participants: Veterans (n = 8836) who were prescribed a modem-enabled PAP device.

Design: Secondary analysis of clinical data. We used path analysis to examine: (1) whether Veterans with a history of TBI were more likely to experience insomnia, PTSD, depression, and chronic pain; (2) in turn, whether Veterans with these co-morbid conditions exhibited lesser PAP adherence; and (3) whether Veterans with a history of TBI will exhibit lesser PAP adherence, even while accounting for such co-morbid conditions. Model estimates were adjusted for sociodemographic (eg, race/ethnicity) and clinical characteristics (eg, mask leakage).

Main measures: Health conditions were abstracted from the VHA medical record. PAP adherence was measured using average nightly use (hours).

Results: Among 8836 Veterans, 12% had a history of TBI. TBI history was not associated with PAP adherence when accounting for the presence of insomnia, PTSD, depression, and chronic pain. Indirect effect estimates indicated that a history of mild, moderate-severe, or unclassified TBI was associated with lesser PAP adherence, as mediated by the presence of co-morbid insomnia and chronic pain. Generally, TBI was associated with an increased likelihood of co-morbid insomnia, PTSD, depression, and chronic pain. In turn, insomnia and chronic pain, but not PTSD or depression, were associated with lesser PAP adherence.

Conclusions: Our study offers empirical support for insomnia and chronic pain as potential explanatory mechanisms underlying the relationship between TBI history and suboptimal PAP adherence. While additional research is needed to confirm causality, findings offer preliminary evidence that can inform the development of tailored PAP adherence interventions for Veterans with TBI and obstructive sleep apnea.