Both groups were assessed for disease severity (MDS-UPDRS), cognition (NIH Toolbox® cognition battery, Trail Making Test), psychological symptoms (Hospital Anxiety and Depression Scale, MDS-UPDRS-I) and QoL (PDQ-39, MDS-UPDRS-II).
We evaluated the two groups with Montreal Cognitive Assessment (MoCA), Mini Mental Status Examination (MMSE), Frontal Assessment Batter (FAB), Beck Depression Index (BDI-II), REM Sleep Behavior Disorder Single-Question Screen (RBD1Q), MDS-UPDRS items related to axial disability and freezing.
Higher severity of constipation correlated with older age (r = 0.728, P < 0.001), higher MDS-UPDRS total score (r = 0.285, P < 0.001), worse postural instability (r = 0.190, P = 0.012), rapid eye movement sleep behaviour disorder (r = 0.228, P < 0.0001) and depression (r = 0.187, P = 0.024).
The following patients' characteristics were measured: disease severity (MDS-UPDRS); cognitive status (MoCA); non-motor signs (NMSS); quality of life (PDQ-8); anxiety and depression (HADS); and levodopa equivalent dose.
A stepwise regression model predicting the MDS-UPDRS part II score identified the Hoehn and Yahr stage, followed by the number of sleep-related symptoms (PD-SP, EDS and pRBD), disease duration, MDS-UPDRS part III score, PIGD subtype, depression and MDS-UPDRS part IV score as significant predictors.