Characterizing Extreme Phenotypes for Pain Catastrophizing in Persons With Chronic Pain Following Mild to Severe Traumatic Brain Injury Requiring Inpatient Rehabilitation: A NIDILRR and VA TBI Model Systems Collaborative Project.

OBJECTIVE

Define and characterize extreme phenotypes of pain catastrophizing for persons with chronic pain following mild to severe traumatic brain injury (TBI) requiring inpatient rehabilitation.

SETTING

18 TBI Model System (TBIMS) centers.

PARTICIPANTS

1762 TBIMS participants 1 to 30 years post-injury reporting chronic pain.

DESIGN

Cross-sectional, secondary analyses.

PRIMARY MEASURES: Catastrophizing, sociodemographic, injury, functional outcome, pain, and treatment characteristics.

RESULTS

Participants were male predominantly (73%), White (76%), middle-aged (mean 46.5 years), injured in motor vehicle accidents (53%) or falls (20%). Extreme phenotypes were identified based on upper and lower 25 th percentiles to create low catastrophizing (N = 434) and high catastrophizing (N = 458) groups. Bivariate comparisons found significant differences ( P < .001) on all measures of concurrent function and pain interference with those in the low catastrophizing phenotype experiencing better function and lower pain interference than those in the high catastrophizing phenotype. Combination Lasso and logistic regression identified multivariable predictors of phenotypes. Increased odds of high versus low catastrophizing extreme phenotypes were associated being younger (odds ratio [OR] = 1.24 for a 10-unit decrease), less than a college level of education (OR = 1.70-2.53), no military history (OR = 3.25), lower FIM motor (OR = 1.20 for a 5-unit decrease) and cognitive (OR = 1.53 for a 5-unit decrease) scores, increased pain intensity (OR = 1.22 for a 1 unit increase) and pain interference (OR = 1.93 for a 1-unit increase), neuropathic type pain (OR = 1.82-1.86), and migraine type pain versus no head pain (OR = 1.65).

CONCLUSION

High pain catastrophizing phenotypes were associated with a greater degree of pain and functional disability and higher likelihood of neuropathic pain and migraine headache. Given pain catastrophizing's contribution to pain-related disability and treatment outcomes, additional research is necessary to investigate its role in adjustment to chronic pain among individuals with TBI. Adapting evidence-based interventions for this population that specifically targets pain catastrophizing is warranted.