Estimating the National Population of Hospitalized Chronic Baclofen Users: A Cross-Sectional Analysis of a Commercial Claims Database

Background Baclofen is an effective treatment for spasticity. Abrupt cessation of intrathecal (IT) or oral baclofen risks the development of withdrawal symptoms; however, the magnitude of the problem is unknown. Objectives The aims for this study were as follows: (1) using an administrative claims database, estimate the number of patients in the United States on baclofen, and (2) estimate the annual percent hospitalized pediatric and adult populations consequently at risk for interruption of chronic baclofen therapy. Methods Using 2011–2014 data representing commercially insured individuals, patients were selected based on insurance coverage; evidence of a baclofen claim; and hospitalization. All patients hospitalized while receiving chronic baclofen were assumed to be at risk for baclofen discontinuation. Yearly counts were determined and then extrapolated to national estimates using census data. Results Extrapolating from the claims database, oral or IT baclofen was prescribed annually to 33,061 or 1486 patients ≤ 18 years, and 654,294 or 7084 patients 19–64 years, respectively. The estimated national mean number of at-risk hospitalizations per year for patients aged 19–64 years on chronic oral or IT baclofen was 31,116 and 3774, respectively; patients ≤ 18 years numbered 4691 and 959, respectively. The mean percent of patients hospitalized per year was 42% in those ≤ 18 years receiving IT baclofen compared with 30% in adults, and 3–10% in the populations receiving oral baclofen. Conclusions Extrapolation from an administrative claims database was used to estimate the national number and demographics of hospitalized chronic baclofen users. Patients ≤ 18 years receiving IT baclofen were at highest risk of withdrawal due to a high occurrence of hospitalization.