Measurement of patient-centered outcomes in Parkinson's disease: what do patients really want from their treatment?

BACKGROUND: Parkinson's disease (PD) impacts several domains of functioning, some of which may be neglected when designing treatment or evaluating outcome using current clinical standards. We therefore argue that taking the patients' perspectives of their condition may allow for a more in-depth assessment of patient goals and subsequent tailoring of care.
METHODS: One hundred and forty-eight patients with idiopathic PD completed a modified version of the Patient-Centered Outcomes Questionnaire (PCOQ-PD), to evaluate treatment success and expectations from the patient's perspective across 10 motor and non-motor functional domains. We also examined patient subgroups based on importance of improvement in various domains.
RESULTS: Patients' ratings suggested there was substantial variation in functional interference that was generally unrelated to demographic variables. On average, across all domains, patients indicated a 50.32% reduction in symptoms would be successful (range = 40.63-58.23%), regardless of treatment experience. Change scores between patients' usual levels of symptom interference and their treatment success levels suggested a greater degree of change was desired in motor versus non-motor domains (p < 0.05). Finally, cluster analyses revealed two patient subgroups based on overall importance of improvement (High vs. Low Importance Endorsement). Notably, the two groups differed in self-reported usual symptom levels despite having similar clinical severity.
CONCLUSIONS: We empirically examined treatment success from the PD patient's view as opposed to clinician judgment alone, thereby broadening the set of criteria by which to evaluate outcome. Findings from this exploratory study may guide future treatment emphases and guide patient-provider communication via clarification of patient-defined success.