Levodopa dosage determines adherence to long-acting dopamine agonists in Parkinson's disease.

Objective: To test whether adherence to non-ergot, once-daily dopamine agonist (ODDA) therapy depends upon concomitant levodopa daily dose in Parkinson's disease (PD).

Methods: Consecutive levodopa-treated PD patients on ODDA therapy were invited to participate in the study. ODDA adherence was measured using subjective (Morisky-Green test, MGT) and objective (electronic monitoring of refill compliance, IANUS) methods.