Low Sustainment of High-Dose Oral Medication Regimens for Advanced Parkinson’s Disease in Medicare Beneficiaries

Article type: Research Article

Authors: Dahodwala, Nabila^{a; b; *} | Jahnke, Jordan^c | Pettit, Amy R.^d | Li, Pengxiang^{b; c} | Ladage, Vrushabh P.^{b; c} | Kandukuri, Prasanna L.^e | Bao, Yanjun^e | Zamudio, Jorge^e | Jalundhwala, Yash J.^e | Doshi, Jalpa A.^{b; c}

Affiliations: [a] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA | [b] Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA, USA | [c] Division of General Internal Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA | [d] Center for Public Health Initiatives, University of Pennsylvania, Philadelphia, PA, USA | [e] AbbVie Inc., North Chicago, IL, USA

Correspondence: [*] Correspondence to: Nabila Dahodwala, MD, MS, Department of Neurology, Perelman School of Medicine, University of Pennsylvania, 330 South 9th Street, 2nd Floor, Philadelpia, PA 19107, USA. E-mail: nabila.dahodwala@uphs.upenn.edu.

Abstract: Background:Increasing doses of oral antiparkinson medications are indicated in advanced Parkinson’s disease (PD), but little is known about sustainment of high-dose regimens. Objective:To investigate sustainment of high-dose oral medication regimens in Medicare beneficiaries with incident advanced PD. Methods:This retrospective cohort study utilized 100%fee-for-service Medicare claims from 2011–2013. We identified advanced PD using a pharmacy claims-based proxy and selected patients who initiated a new high-dose oral medication regimen (daily levodopa equivalent dose [LED] >1000 mg/day for ≥30 days) in 2012. In the following 12 months, we examined: 1) annual proportion of days covered (PDC)≥0.80 and 2) presence of a ≥ 90 day continuous gap at varying dosage thresholds: the initial >1000 mg/day, >800 mg/day, >500 mg/day, or >0 mg/day. Results:We identified 9,405 patients with advanced PD (mean age 77.4 [SD 6.8] years; 53%men). Only 5%maintained a regimen of >1000 mg/day at PDC ≥0.80; 75% had a ≥ 90-day gap in that dosage level. At a dosage threshold of >800 mg/day, 20% had a PDC ≥0.80 and 53% had a ≥ 90-day gap; at >500 mg/day, 56% had a PDC ≥0.80 and 19%had a ≥ 90-day gap; and at >0 mg/day (any dose), 76% had a PDC ≥0.80 and only 10%had a≥90-day gap. Conclusion:Few patients with advanced PD sustained a high-dose oral medication regimen in the year following initiation, but most sustained a substantially lower-dose regimen. Strategies to improve advanced PD treatment are needed.

Keywords: Advanced Parkinson’s disease, prescribing patterns, discontinuation, Medicare, administrative claims

DOI: 10.3233/JPD-202147

Journal: Journal of Parkinson's Disease, vol. 11, no. 2, pp. 675-684, 2021