Persistence and adherence to levodopa adjunct medications in elderly patients with Parkinson's disease: a retrospective cohort study using a Japanese claims database.

OBJECTIVE

We investigated treatment persistence and adherence for levodopa adjunct medications and their relationship with demographic factors in Japanese patients with Parkinson's disease (PD).

METHODS

This longitudinal retrospective study used a Japanese health insurance claims database for levodopa adjunct medications in patients newly prescribed anti-PD drugs other than levodopa between December 2020 and November 2021. Patients with a PD diagnosis were included in this study, and 17 anti-PD drug cohorts were formed. The primary outcomes were treatment persistence and adherence over 1 year. Multivariate analysis was conducted to evaluate demographic factors associated with treatment persistence/adherence.

RESULTS

In total, 7,605 patients were included in this analysis, with a mean age of 77.2 years, and 43.6% were male. The 1-year treatment persistence rate was 44.8%. Median persistent treatment duration over 1 year was 270.0 days. Persistence rates ranged from 28.6 to 59.5% across the drug cohorts, and were highest for zonisamide (59.5%) followed by safinamide (55.8%). The proportion of patients with proportion of days covered ≥80% (good treatment adherence) was 96.9% in the all-drugs cohort and ≥ 90% in each drug-specific cohort. In the multivariate analysis, the factor most strongly associated with non-persistence was the number of concomitant anti-PD drugs (risk ratio [RR] 0.85 per 1 unit increase), with the exception of inpatient prescriptions (RR 0.75).

CONCLUSION

More than half of the new anti-PD drugs added to levodopa were discontinued within 1 year, and adherence to treatment, as assessed by filling records, was extremely high in patients with PD, including the elderly population.