Longitudinal assessment of autonomic dysfunction in early Parkinson's disease

Clinical correlates of autonomic nervous system (ANS) dysfunction in early Parkinson's disease (PD) have been addressed mainly in a cross-sectional way.

This is a combined cross-sectional and longitudinal prospective study of ANS dysfunction using the SCOPA-AUT in PD patients at the Hoehn and Yahr stage 1 with disease duration <2 years. PD patients (n = 107) were compared to healthy controls (HC, n = 79), and then followed-up for over 3 years. The severity of PD, depression, anxiety, apathy and cognitive impairment were evaluated using rating scales.

At least one symptom of ANS dysfunction was present in 71% of PD patients in comparison to 30.4% of HC, and in all PD patients after three years. The overall severity of dysautonomia symptoms was mild (SCOPA-AUT mean ± SD; 4.16 ± 5.0), but worsened by 23%, 86% and 0.3% during the 1st, 2nd and 3rd year respectively. Nighttime voiding (38.3%), constipation (30.8%) and straining for defecation (29%) were the most common symptoms. Prevalence and severity of urinary, gastrointestinal, and orthostatic symptoms increased, in contrast to thermoregulatory and pupillomotor symptoms. Frequency of symptoms suggestive of multi-domain ANS dysfunction rose from 49% to 79%. Psychiatric symptoms and age, but not motor impairment, were associated with dysautonomia symptoms.

Symptoms of ANS dysfunction were frequent in the initial motor stage of PD and progressed, yet remaining mild, within 3 years. An independent progression of dysautonomia symptoms from motor disability and its associations with non-motor, mainly psychiatric symptoms and age support the non-motor clustering in PD.