Dysphagia in Parkinson´s disease. A 5-year follow-up study.

Background And Objective: Dysphagia at time of diagnosis suggests atypical parkinsonism instead Parkinson´s disease (PD). Our aim was to analyze the frequency of dysphagia in patients with early PD comparing with a control group and to identify related factors.

Patients And Methods: Patients with early PD (≤ 2 years from symptoms onset) who were recruited from January/2016 to November/2017 (baseline visit; V0) and evaluated annually for 5 years from the Spanish cohort COPPADIS were included in this prospective study. Controls were assessed at baseline and at 2-, 4-, and 5-year follow-up. Dysphagia was defined as a score ≥ 1 in the item 20 of the Non-Motor Symptoms Scale (NMSS).

Results: Dysphagia was more frequent at baseline in PD patients (19.6% [36/184]; 62.3 ± 8.3 years old; 56.8% males) than in controls (5.3% [11/206]; 60.9 ± 8.3 years old; 50% males) (p < 0.0001) and in all visits as well (p < 0.0001). A worse quality of sleep (Parkinson´s Disease Sleep Scale; OR = 0.974; p = 0.005), a greater impulse-control behavior (ICB) (Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale; OR = 1.066; p = 0.014), and non-motor symptoms burden (Non-Motor Symptoms Scale; OR = 1.016; p = 0.021) were independent factors associated with dysphagia at baseline. In those subjects with dysphagia, no differences were observed between patients and controls in the mean NMSS-item 20 overtime, and it didn´t change throughout the follow-up.

Conclusion: Dysphagia was frequent in early PD patients compared to controls. However, it was minor and did not progress over time. Sleep, ICB, and non-motor symptoms burden were related to dysphagia.