Disparities in Morbidity After Spinal Cord Injury Across Insurance Types in the United States

Abstract

Objective: To compare the prevalence and incidence of, and adjusted hazards for comorbidities among adults with traumatic spinal cord injuries (TSCIs) across insurance types (private vs governmental insurance) in the United States.

Patients and methods: Privately insured (N=9081) and Medicare (N=7645) beneficiaries with a diagnosis of TSCI were included. Prevalence and incidence estimates of common psychological, cardiometabolic, and musculoskeletal morbidities were compared at baseline and at 4-years after index diagnosis, respectively. Survival models were used to quantify hazard ratios (HRs) for outcomes, controlling for insurance type, sociodemographic characteristics, and other comorbidities. Sensitivity analyses were conducted to determine the effects of insurance and race/ethnicity.

Results: Adults with TSCIs on Medicare had a higher prevalence of any psychological (54.7% vs 35.4%), cardiometabolic (74.7% vs 70.1%), and musculoskeletal (72.8% vs 66.3%) morbidity than privately insured adults with TSCIs. Similarly, the 4-year incidences of most psychological (eg, depression: 37.6% [Medicare] vs 24.2% [private]), cardiometabolic (eg, type 2 diabetes: 22.5% [Medicare] vs 12.9% [private], and musculoskeletal (eg, osteoarthritis: 42.1% [Medicare] vs 34.6% [private]) morbidities were considerably higher among adults with TSCIs on Medicare. Adjusted survival models found that adults with TSCIs on Medicare had a greater hazard for developing psychological (HR, 1.40; 95% CI, 1.31-1.50) and cardiometabolic (HR, 1.21; 95% CI, 1.10-1.33) morbidities compared with privately insured adults with TSCI. There was evidence of both insurance and racial disparities.

Conclusion: Adults with TSCIs on Medicare had significantly higher prevalence and risk for developing common physical and mental health comorbidities, compared with privately insured adults with TSCIs.

Keywords: CMS, Centers for Medicaid and Medicare Services; HR, hazard ratio; SDoH, social determinants of health; SMD, standardized mean difference; TSCI, traumatic spinal cord injury.

Figure 1

Flow chart of participants’ inclusion and exclusion for patients with TSCI on Medicare and patients with TSCI on private insurance. TSCI = traumatic spinal cord injury.

Figure 2

Disease-free survival and Kaplan-Meier product-limit survival curves (3-year) for Medicare beneficiaries with TSCIs (blue) and privately insured beneficiaries with TSCIs (red), for any (A) psychological morbidity, (B) cardiometabolic disease, and (C) musculoskeletal disorder. TSCI = traumatic spinal cord injury.