Relationship between the non-motor items of the MDS-UPDRS and Quality of Life in patients with Parkinson's disease.

The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is a newly developed comprehensive tool to assess Parkinson's disease (PD), which covers a wider range of non-motor PD manifestations than the original UPDRS scale. The aim of this study was to assess the relationship between the MDS-UPDRS and Quality of Life (QoL) and to analyze the relationship between individual MDS-UPDRS non-motor items and QoL. A total of 291 PD patients were examined in a multicenter Slovak study. Patients were assessed by the MDS-UPDRS, HY scale and PDQ39. Data were analyzed using the multiple regression analyses. The mean participant age was 68.0 ± 9.0 years, 53.5% were men, mean disease duration was 8.3 ± 5.3 years and mean HY was 2.7 ± 1.0. In a multiple regression analysis model the PDQ39 summary index was related to MDS-UPDRS parts II, I and IV respectively, but not to part III. Individual MDS-UPDRS non-motor items related to the PDQ39 summary index in the summary group and in the non-fluctuating patients subgroup were pain, fatigue and features of dopamine dysregulation syndrome (DDS). In the fluctuating PD patient subgroup, PDQ39 was related to pain and Depressed mood items. Other MDS-UPDRS non-motor items e.g. Anxious mood, Apathy, Cognitive impairment, Hallucinations and psychosis, Sleep problems, Daytime sleepiness and Urinary problems were related to some PDQ39 domains. The overall burden of NMS in PD is more important in terms of QoL than motor symptoms. Individual MDS-UPDRS non-motor items related to worse QoL are especially pain and other sensations, fatigue and features of DDS.