ASSOCIATION OF EDUCATION WITH COGNITIVE FUNCTION IN NEWLY DIAGNOSED PARKINSON’S DISEASE

Abstract

Parkinson’s disease (PD) is the second most common neurodegenerative disorder. Low education is known to be a risk factor for Alzheimer’s disease (AD). Since many patients with PD show pathological findings similar to AD in addition to Lewy body, we reasoned that low education might also be associated with decreased cognition of PD Methods. We studied 154 unrelated PD patients recruited consecutively from May 2003 until March 2008 in the outpatient Movement Disorder Clinic of the Daegu Catholic University Medical Center. The diagnosis was made through manifestations of two or more cardinal features of PD: initially unilateral resting tremor, bradykinesia or rigidity, levodopa-responsiveness, and absence of clinical features of atypical PD. The 150 controls were without a diagnosis of a neurodegenerative disorder, who were the spouses or other caregivers of the patients. Cognitive function was assessed using a standardized cognitive function test, Seoul Neuropsychological Screening battery. Results. The number of women was higher in PD patients, contrasting with Controls (p=0.000). The mean score of the Korean-mini mental state examination (K-MMSE) of PD was lower than that of controls (p=0.008). Patients with lower education related with higher age (p=0.030), higher women proportion (p=0.000), lower alcohol drinking (p=0.028), older age at onset (p=0.024), higher Unified Parkinson Disease Rating Scale part III score (p=0.050), lower K-MMSE (p=0.000), higher Geriatric Depression Scale (GDS) score (p=0.020). K-MMSE score of PD patients is strongly related to education level after adjusting age, sex, and GDS (p=0.000). Lower education (p=0.000) and higher GDS (p=0.007) has an association with lower K-MMSE in PD by univariate regression analysis. Conclusion. As we hypothesized, newly diagnosed PD with low education showed lower cognitive performance. PD itself was seemed to be a risk factor for lower cognition as well as depression.