Parkinson disease (PD) is a risk factor for dementia. In addition, specific cognitive deficits can occur in PD patients without dementia. A patient's level of education could have an influence on the development of cognitive impairment in PD. The aim of this study was to examine the relationship between the level of education and cognitive performance in non-demented patients with PD.

Thirty-seven consecutive, nondemented PD patients and 40 healthy controls fulfilled the inclusion criteria and were enrolled in the case-control study. Each of the controls and PD patients were classified, for the purpose of this study, into one of three groups (low, intermediate, higher), categorized by the number of years of education. There were no differences in education and age between the controls and PD patients. All of the subjects were evaluated with a battery of neuropsychological tests: Mini-Mental State Examination, Trail Making Tests, Stroop Test, Mental Rotation Test, and Verbal Fluency Test.

Less (low and intermediate) education was correlated with poor results from tests. The comparison of all groups of PD patients and controls demonstrated that PD subjects received lower test scores, especially for the low and intermediate groups. However, no statistically significant difference was reached between educationally advanced PD patients and the appropriate control subjects.

As compared to the controls, most non-demented PD patients presented executive-type cognitive dysfunction. The higher educational level, however, was associated with a lower risk of cognitive deterioration. We conclude that higher education might have protective effects in cognitive decline in PD.