We reviewed data from patients with PD evaluated for DBS, including OFF/ON levodopa motor scores and cognitive assessments (MoCA and/or DRS-2). Patients were grouped based on %LR: Low (<30%), Moderate (30-50%), and Good (>50%). Differences in MoCA and DRS-2 scores among groups were analyzed using the Kruskal-Wallis test with Dunn’s post-hoc comparisons. Spearman’s correlation assessed the relationship between %LR and cognitive measures, and generalized linear models (GLM) were used to adjust for age and disease duration.
A total of 279 patients (mean age: 64.1 years, disease duration: 9.2 years) were included. Of these, 240 had MoCA scores (mean±SD: 25.8±3.4) and 203 had DRS-2 scores (mean±SD: 135.6± 6.2) available. MoCA scores were significantly different among groups (p=0.001), with the Good response group having higher scores compared to the Low (p=0.003) and Moderate (p=0.018) groups. DRS-2 scores showed no significant differences (p=0.231) across groups. There was a positive correlation between %LR and MoCA scores (rho=0.28, p<0.001), while %LR and DRS-2 scores showed no significant correlation. After adjusting for age and disease duration, GLM showed %LR was significantly associated with MoCA (p<0.001), while its effect on DRS-2 was smaller (p=0.041).
Levodopa response is associated with cognitive function, particularly as measured by MoCA. Further longitudinal studies may provide insights into whether motor response to levodopa can predict cognitive function over time.