Influence of the level of education on cognitive function in Parkinson’s disease

Abstract

Level of Education (LoE) is widely used as an indicator of cognitive reserve and is associated with risk of dementia. The aim of the present study was to know the influence of the LoE on cognitive function (CF) in patients with Parkinson´s disease (PD). Controls and PD patients from the Spanish cohort COPPADIS with a disease duration from symptoms onset ≤ 5 years, who were recruited from January/2016 to November/2017 (baseline visit; V0) and evaluated at 2 (V2), 4 (V4) and 5 (V5) years of follow-up were included. Regarding LoE, patients were classified as with primary, secondary and university education. CF was assessed using the Parkinson´s Disease Cognitive Rating Scale (PD-CRS). General linear model (GLM) repeated measure was used to test for changes in the CF. A p value ≤ 0.005 was considered significant. Three hundred and ninety-nine PD patients (61.9 ± 8.9 years old; 58.4% males) and 207 controls (61 ± 8.3 years old; 49.8% males) were included. From V0 to V5, significant differences were observed in PD patients in global and fronto-subcortical (p < 0.0001 in all visits) between LoE groups but not in posterior-cortical (p > 0.05 in all visits) CF. LoE was associated with the change from V0 to V5 in the PD-CRS total score and fronto-subcortical sub-score (p < 0.0001) in PD patients but not in controls. After adjustment for many covariates, primary education was not a predictor of PD dementia (PD-CRS < 65) at V5 (OR = 3.31; p = 0.194). Cognitive function in Parkinson’s disease is influenced by the level of education.