A home diary to assess functional status in patients with Parkinson's disease with motor fluctuations and dyskinesia

In clinical trials For patients with Parkinson's disease (PD) with motor fl uctuations, efficacy is generally ascribed to an intervention if motor func tion is significantly improved or if "off " time is significantly reduced. However, we have argued that patients might not be improved if off lime is reduced only to the extent that unwanted dyskinesia is increased. Therefore , a home diary should include an assessment of dyskinesia to provide an acc urate reflection of clinical status over a period of time. We undertook two studies to develop a home diary to assess functional status in patients wi th PD with motor fluctuations and dyskinesia. In both studies, patients con currently completed a test and a reference diary. In Study I, we evaluated the impact of different severities of dyskinesia on patient-defined functio nal status. There were 1,149 evaluable half-hour time periods from 24 patie nts; 94.3% of off time was considered "bad" time and 90.2% of " on" time wi thout dyskinesia, 72.6% of on time with mild dyskinesia, 43.0% of on time w ith moderate dyskinesia, and 15.2% of on time with severe dyskinesia was co nsidered "good" time. In Study II, we evaluated a new home diary designed t o separate dyskinesia that had a negative impact on patient-defined functio nal status from dyskinesia that did not. There were 816 evaluable time peri ods from 17 patients; 84.9% of off time and 89.9% of on time with troubleso me dyskinesia was considered bad time while 85.5% of on time without dyskin esia and 93.8% of on time with nontroublesome dyskinesia was considered goo d time. With this diary (Diary II), the effect of an intervention can be ex pressed as the change in off time and the change in on time with troublesom e dyskinesia (bad time). The sum can be used as an outcome variable and com pared to baseline or across groups. in evaluating the efficacy of an interv ention, assessment of change in off time and change in on time with trouble some dyskinesia provides a more accurate reflection of clinical response th an change in off time alone.