Pain interference and health-related quality of life in caregivers of service members and veterans with traumatic brain injury and mental health comorbidity

Purpose To examine (1) the relationship between caregiver pain interference with caregiver health-related quality of life (HRQOL), caregiver age, and service member/veteran (SMV) functional ability, and (2) change in caregiver pain interference longitudinally over 5 years. Method Participants were 347 caregivers of SMVs diagnosed with traumatic brain injury (TBI). Caregivers completed the SF-12v2 Health Survey Bodily Pain scale at an initial baseline evaluation and up to four annual follow-up evaluations. Caregivers were divided into three pain interference groups: High Pain Interference (n = 104), Neutral Pain Interference (n = 117), and Low Pain Interference (n = 126). Caregivers also completed 15 HRQOL measures and a measure of SMV functional ability. Results The High Pain Interference group reported more clinically elevated scores on 13 measures compared to the Low Pain Interference group, and seven measures compared to the Neutral Pain Interference group. The Neutral Pain Interference group had more clinically elevated scores on three measures compared to the Low Pain Interference group. The High and Neutral Pain Interference groups were older than the Low Pain Interference group. Parent caregivers were older than intimate partner/sibling caregivers, but did not report worse pain interference. Caregiver age, and measures of Fatigue, Strain, Perceived Rejection, and Economic QOL were the strongest predictors of pain interference (p < .001), accounting for 28.2% of the variance. There was minimal change in Bodily Pain scores over five years. The interaction of time and age was not significant (X-2 = 2.7, p = .61). Conclusion It is important to examine pain in the context of HRQOL in caregivers, regardless of age.