Predictors of Dopamine Dysregulation Syndrome in Patients with Early Parkinson's Disease

Background: Dopamine dysregulationsyndrome (DDS) is a complication of Parkinson's disease (PD) that seriously affects the quality of life of PD patients. Currently, the risk factors for DDS are unknown, and it is critical to identify them in the early stages of PD. Objective: To explore the incidence of and risk factors for DDS in patients with early PD. Methods: : A retrospective cohort study was conducted on the general data, clinical features and imaging data of patients with early PD in the PPMI database. Multivariate Cox regression analysis was performed to analyze the risk factors for the development of DDS in patients with early PD, and Kaplan‒Meier curves examined the frequency and predictors of incident DDS symptoms. Results: : At baseline, 2.2% (n=6) of patients with early PD developed DDS, and the cumulative incidence rates of DDS during the 5-year follow-up period were 2.8%, 6.4%, 10.8%, 15.5% and 18.7%, respectively. In the multivariate Cox regression model controlling for age, sex and drug use, hypersexuality (HR=3.088; 95% CI: 1.416~6.732; P =0.005), compulsive eating (HR=3.299; 95% CI: 1.665~6.534; P =0.001), compulsive shopping (HR=3.899; 95% CI: 1.769~8.593; P =0.001), anxiety(HR=4.018; 95% CI: 2.136~7.599; P <0.01) and lower Hoehn-Yahr (H-Y) stage (HR=0.278; 95% CI: 0.152~0.509; P <0.01) were independent risk factors for DDS in patients with early PD. Dopamine transporter (DAT) uptake in PD patients with DDS was lower after follow-up than at baseline. Conclusion: Early PD patients with a hypersexuality, compulsive eating, compulsive shopping, anxiety and lower H-Y stage were at increased risk for DDS. The occurrence of DDS may be related to the decrease in the average DAT uptake of the caudate and putamen.