Concordance between severity of disease, prevalence of nonmotor symptoms, patient-reported quality of life and disability and use of medication in Parkinson’s disease

The aim of this study was to test the concordance between disease severity, prevalence of nonmotor symptoms, age, health-related quality of life (HRQoL), disability and medication use in patients with Parkinson’s disease (PD). Severity was classified with the Hoehn and Yahr (HY) scale and Levodopa Equivalent Daily Dose (LEDD) calculated. HRQoL was evaluated with the SF-36, disability with the WHO-DAS II and nonmotor symptoms with the NMSQuest. Patients were clustered using SF-36 and WHO-DAS II into three groups covering the continuum from low disability and HRQoL, to severe disability and HRQoL decrement. Contingency Coefficient were used to verify the relationships between clusters and HY stage; ANOVA to evaluate differences in NMS, age and LEDD between clusters; odds ratio to test the likelihood of taking levodopa or dopamine agonist and being member of the three clusters; t test to evaluate differences in LEDD between patients with HY ≥3 or ≤2. Eighty-six patients were clustered: 48 had low disability and HRQoL decrement, 18 intermediate disability and HRQoL decrement and 20 high disability and HRQoL decrement. A significant relationship was found between PD severity groups, HRQoL and disability profiles. No differences for age and LEDD were observed in the three groups, and those with more disability and lower HRQoL reported a higher number of nonmotor symptoms; patients in HY ≥3 were prescribed higher doses of drugs. In conclusion, we found a substantial concordance between PD staging, prevalence of nonmotor symptoms and patient-reported HRQoL and disability measures. In our opinion, the SF-36 and the WHO-DAS II can be used for profiling patients.