Medical Student Duke University Durham, North Carolina, United States
Introduction: Chronic spasticity causes impairment as well as economic hardship. The first-line therapy, oral baclofen, can have intolerable, dose-dependent side effects. TDD delivers smaller amounts of baclofen into the thecal sac through an implanted infusion system. The utilization of healthcare resources by spasticity patients with TDD has received little attention.
Methods: Using the IBM MarketScan® databases, we identified adult patients who received baclofen TDD for spasticity between 2009 and 2017. The use of oral baclofen, inpatient and outpatient costs, and medication costs were studied from the beginning (1 year before implantation) to 3 years after implantation. To compare post-implantation costs to baseline, multivariable regression with generalized estimating equations and a log link was used.
Results: We identified 685 patients with TDD for medication analysis and 512 for cost analysis. At baseline, 62% of patients took oral baclofen, decreasing to 24% by the third year. The median annual daily baclofen dose was reduced from 63 (IQR 40-87) mg pre-implantation to 33 (IQR 30-64) mg 3 years later. At baseline, median total costs were $39,736 (IQR $20,797-$82,054), which increased to $74,615 (IQR $44,548-$120,810) in year 1, decreased to $28,025 (IQR $13,107-$63,168) in year 2, and increased slightly to $30,730 (IQR $12,514-$67,173) in year 3. In multivariable analysis, the cost was 49% higher than baseline (cost ratio [CR] 1.49, 95% CI: 1.36-1.62, p< 0.001) in year 1 but was 22% lower (CR 0.78, 95% CI: 0.7-0.87, p< 0.001) in year 2 and 26% lower (CR 0.74, 95% CI: 0.65-0.85, p< 0.001) in year 3.
Conclusion : TDD patients use less oral baclofen, potentially lowering the risk of side effects. While total costs increased in the year following TDD due to device and implantation costs, they fell below baseline after one year. TDD costs can be recovered after three years of use, indicating potential long-term cost savings.
