Assessment of Clinical and Demographic Factors Influencing the Severity of Levodopa-Induced Dyskinesia

ABSTRACT Background: Levodopa-induced dyskinesia (LID) is a disabling symptom of Parkinson’s disease (PD). There have been prior attempts to find risk factors contributing to this symptom, but risk factors for the severity of LID have not been comprehensively studied. We aimed to evaluate factors that correlate with LID severity in patients with PD based on the Unified Dyskinesia Rating Scale (UDysRS). Methods: A cross-sectional study was designed on 52 idiopathic PD patients who were referred for LID between 2023 and 2024. Their demographic and clinical records were studied. Furthermore, cognitive decline (MoCA), PD severity (Hoehn and Yahr) and the severity of dyskinesia (UDysRS) were examined. The association between factors and LID severity was evaluated by carrying out univariate regression and multivariate regression backward elimination analysis. Results: The mean age of patients with LID was 59.9 ± 11.4 years. Results of univariate regression analysis indicated that male sex ( β = −0.24, P = 0.04), BMI ( β = −0.3, P = 0.005), H&Y ( β = 0.4, P = 0.002), diabetes mellitus ( β = 0.3, P = 0.018) and levodopa dosage per kilogram ( β = 0.37, P = 0.01) were significant factors involved in the severity of dyskinesia. The univariate regression model results showed that lack of constipation ( P = 0.04), hyperlipidemia ( P = 0.04) and total daily levodopa dosage per kilogram ( P = 0.01) were associated with the severity of end-dose dystonia. Conclusion: This study revealed that female sex, more advanced PD, diabetes mellitus, daily levodopa dosage per kilogram body weight and BMI are associated with the severity of LID. Also, it suggests that hyperlipidemia and lack of constipation are associated with the severity of end-dose dystonia.