Abstract
INTRODUCTION: Complex polypharmacy regimens to manage persistent motor fluctuations result in significant pill burden for patients with advanced Parkinson's disease (APD). This study evaluated the effectiveness of carbidopa/levodopa enteral suspension (CLES) and deep brain stimulation (DBS) on reducing pill burden in APD patients. METHODS: We utilized 100% Medicare fee-for-service claims from 2014 to 2018 linked to CLES Patient Support Program (PSP) data. CLES initiators (CLES-I) were propensity matched 1:1 with patients enrolled in PSP who did not initiate treatment (CLES-NI) (N = 188) or undergo DBS, and 1:3 with patients who received DBS (N = 204, N = 612). Average daily pill burden and levodopa equivalent daily dosage (LEDD) were measured at baseline, 0-6 months and 7-12 months follow-up. RESULTS: CLES-I and CLES-NI had higher pill burden than DBS patients at baseline. However, at 6 months post-treatment, CLES-I had significantly fewer pills/day than CLES-NI (4.7 versus 11.4, p < 0.05) and DBS (4.8 versus 7.4, p < 0.05). A significant reduction in pill burden was observed at 0-6 months (46.3%) and 7-12 months (68.3%) follow-up for CLES-I (p < 0.001) versus increased burden for CLES-NI (+10.5%, p < 0.05 and +8.2%, p > 0.05) and insignificant reductions for DBS (-3.9% and -6.1%, p > 0.05). Mean adjusted pill burden showed 57.3% fewer pills at 0-6 months and 74.1% at 7-12 months among CLES-I compared with CLES-NI, and 49.6% and 70.1% reduction compared with DBS. CLES-I showed a decrease in LEDD at 7-12 months compared with baseline (935 to 237 mg) and to CLES-NI (237 mg versus 1112 mg) and DBS patients (236 mg versus 594 mg). CONCLUSION: CLES led to a significant reduction in pill burden and oral LEDD compared with CLES-NI and DBS patients. Pill burden reduction could be considered a treatment goal for patients with APD challenged by complex polypharmacy regimens that interfere with activities of daily living and quality of life.