• To evaluate dysautonomia prevalence in de novo Parkinson’s disease (PD) patients compared to controls.
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• To evaluate whether dysautonomia in de novo PD is independently associated with functional status.
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• To evaluate whether dysautonomia in de novo PD predicts functional decline.
  

While historically thought of as a feature of later disease, many PD patients report symptoms of dysautonomia on initial presentation. Dysautonomia has been related to worse motor severity but the relationship between dysautonomia and functional status is not well understood, especially in early PD.

Data were obtained from the Parkinson Progression Marker Initiative (PPMI) study, a multicenter observational study of 423 PD patients untreated at baseline and 196 healthy controls (HC). The self-reported questionnaire SCOPA-AUT assessed autonomic dysfunction, and Schwab and England (SE) measured functional status. Autonomic symptoms in the PD and HC groups were compared. The cross-sectional relationship between SCOPA-AUT and SE score in the PD group was determined using a linear regression model. The longitudinal relationship between baseline SCOPA-AUT and hazard ratio (HR) for likelihood to progress to SE<80 (i.e., functional dependence) up to 7 years was determined using Cox models.  All analyses presented were adjusted for age, disease duration, and MDS-UPDRS part 3 score.

Mean SCOPA-AUT was significantly higher in the PD compared to HC group (9.5, SD=6.2 vs. 5.9, SD=3.74, respectively; p<0.001). In the PD group, SCOPA-AUT was significantly associated with a lower SE score at baseline (β=-0.11, p=0.010). Baseline SCOPA-AUT predicted progression to SE<80 up to 7 years; HR=1.05, p<0.001.

In PD, dysautonomia is associated with lower functional status within 2 years of diagnosis and is an independent predictor of functional decline.