Non-motor symptoms in akinesia dominant versus other phenotypes in Parkinson's disease (PD): Results from the international PD non-motor symptoms scale study

Objective: Parkinson‘s disease (PD) can be separated to three different motor patterns: Tremor type (TT), Akinetic-Rigid type (ART) and Mixed type (MT). In this study generated from the international validation study of the recently reported PD non motor symptoms scale (NMSS), we report on the burden of non-motor symptoms and health related quality of life (HrQol, using the Parkinson‘s disease Questionnaire-8 items (PDQ-8)) in these different subgroups of PD. Method: 239 PD patients (137 male, 102 female) were studied; 44 patients (18.4%) have a TT disease, 71 (48.1%) have an ART and 124 (51.88%) a MT. Subjects completed the nine domains, 30 items NMSS, a grade rating scale (Chaudhuri et al. Mov Disord 2007; DOI: 10.1002/mds.21596). Since the population presented a ‟non-normal” dis´┐¢tribution pattern, non parametric tests were used. Results: Sex (p 0.257) and distribution among the Hoehn-Yahr stages (p 0.135) didn‘t significantly differ. No significant differences in PDQ´┐¢8 score (p 0.124) was found, but there was the trend for ART to have higher PDQ-8 while NMSS total score was borderline significantly higher in ART patients (p 0.04). However, combining the RT and MT patients (n 168, 70.29%) versus the AR subjects, NMSS score was significantly worse in ART (63.81±38.74 vs 53.44±41.14, p 0.016) and additionally, with worse PDQ-8 scores (33.34±19.04 and 28.34±18.57, p 0.045). There were no differences in age, sex, duration of disease and UPDRS although ART patients were older than non ART subjects at the onset of disease (63.28±12.88 and 59.43±12.36 respectively, p 0.03). Conclusion: Our data suggest that the burden of non-motor symptoms complex as a whole is higher in Akinetic type PD patients. This appears to have a negative impact on health related quality of life.