Correlation of Dopaminergic Denervation and the Progression of Autonomic Dysfunctions in Different Clinical Subtypes of Parkinson's Disease

Early dopaminergic replacement treatment initiation benefits motor symptoms in patients with Parkinson's disease

Background

Parkinson's disease (PD) generally progresses slowly, but it is controversial whether delaying treatment accelerates the progression.

Objective

Determine the correlation between the time of dopaminergic replacement treatment initiation and the severity of clinical symptoms in PD, including motor and non-motor symptoms.

Methods

PD patients were divided between 155 people who were diagnosed de novo and 165 PD patients receiving dopamine replacement therapy. Basic patient characteristics included gender, age, age at onset, disease duration, and the time of dopaminergic replacement treatment initiation. We used MDS-UPDRS scores to evaluate the severity of motor symptoms and we also used the scale to assess the severity of non-motor symptoms such as cognition, mood, sleep, and quality of life.

Results

The mean time between symptom onset and the initiation of drug treatment was 31.0 (22.5) months. After adjusting for age, sex, age at onset, and disease duration, we found that the MDS-Unified Parkinson's Disease Rating Scale (UPDRS)-III score increased faster in the de novo group with a similar disease duration (F = 8.7, p = 0.0034) than the treatment group. The cumulative incidence of progression to H-Y score 3 in de novo PD group over disease duration was 39.7% in 50months and 92.2% in 100 months, while in treated group such cumulative incidence was 15.5% in 50 months, 51.4% in 100 months and 81.5% in 150 months. The cumulative incidence of patients in the de novo PD group was higher than that in the treated group (p = 0.001), suggesting that untreated patients were more likely to progress to the advanced stages. Symptoms onset, the time between symptom onset and treatment initiation, age, sex, and disease duration explained 28.95% of the total variation in the MDS-UPDRS-III score for motor symptoms. In drug-naïve patients, the time between symptom onset and treatment initiation explained 20.1% of the total variation in the MDS-UPDRS-III score for motor symptoms (t = 6.15, p < 0.001).

Conclusions

These data in our study showed that early dopaminergic replacement treatment have played a positive role in PD patients, while dopaminergic replacement delayed treatment might be detrimental to motor symptoms and non-motor state of PD patient. Recognizing early stage symptoms of PD and early diagnosis are of great significance to treatment.

Association between autonomic dysfunction with motor and non-motor symptoms in patients with Parkinson's disease

To investigate the association between autonomic dysfunction (AutD) and motor as well as non-motor symptoms (NMS) in patients with Parkinson's disease (PD). Fifty-three PD patients were divided into two groups based on the number of domains affected by AutD: a multi-domain AutD group (AutD-M) and a single-domain AutD group (AutD-S), as evaluated using the Scale for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT), which assesses autonomic symptoms, one of the NMS. A comprehensive comparison was conducted between the two groups, including clinical measures such as clinical scales, quantitative evaluations of motor function and exercise capacity. Spearman correlation analysis was employed to investigate the relationship between AutD severity and PD symptoms. Additionally, we performed multiple linear regression model analysis to determine whether associations between SCOPA-AUT scores and clinical assessments remained significant after adjusting for Hoehn and Yahr stage, sex, and age. PD patients in the AutD-M group exhibited significantly more severe NMS and motor symptoms compared to those in the AutD-S group. In correlation analysis, SCOPA-AUT scores showed significant correlations with multiple clinical symptoms, such as most of the NMS, 10-MWT and CPET parameters. Furthermore, regression analysis also revealed that more pronounced fatigue, anxiety, depressive symptoms, worse walking speed and impaired exercise capacity were associated with higher SCOPA-AUT scores. The presence of AutD is correlated with emotional disturbances, decreased exercise endurance, and impaired gait function in patients with PD. Early management of AutD may prove beneficial in alleviating some NMS and motor symptoms in PD.