Pain Intensity, Interference, and Medication Use After Spinal Cord Injury: Association With Risk of Mortality After Controlling for Socioeconomic and Other Health Factors.

OBJECTIVE

To identify the association of pain intensity, pain interference, and pain medication use with risk of mortality after spinal cord injury, controlling for demographic, injury, socioeconomic, and health factors.

DESIGN

Prospective cohort study.

SETTING

Academic medical center.

PARTICIPANTS

All participants (N=2535) had traumatic spinal cord injury of at least 1-year duration at enrollment, with noncomplete recovery (American Spinal Injury Association Impairment Scale grades A-D). Mortality status was obtained for 2535 individuals, and 335 were deceased as of 2014.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Mortality status as of December 31, 2014, identified by the National Death Index.

RESULTS

Preliminary bivariate analyses indicated that deceased participants were more likely to be older at injury, have more years postinjury, be men, and have a severe injury, low income, less education, and poorer health indicators. The final Cox model indicated that those who used pain medication daily were 51% more likely to be deceased at follow-up (hazard ratio [HR], 1.51). Pain intensity and pain interference were not statistically significant. Nonchronic pressure ulcer was related to 67% higher mortality risk (HR, 1.67), and chronic pressure ulcer was related to 122% higher risk (HR, 2.22). Other health indicators also increased the risk of mortality from 43% to 73%, including hospitalization (HR, 1.54), depression (HR, 1.43), and amputation (HR, 1.73).

CONCLUSIONS

Prescription pain medication use appears to have a direct association with mortality, beyond that associated with other characteristics, and should become a strong focus of prevention efforts.