Cognitive Impairment and Dementia in Parkinson’s Disease.

The study aimed to determine the prevalence of cognitive impairment and its progression to dementia in patients with Parkinson’s disease (PD). A total of 106 patients followed in outpatient clinics in Almaty were included. PD diagnosis was confirmed according to international criteria. Cognitive status was assessed using the MMSE and MoCA scales, while disease severity was evaluated with the Hoehn and Yahr scale and the Schwab and England Activities of Daily Living Scale. Mild cognitive impairment (MCI) was found in 26.4% of patients, dementia in 34.9%, and no cognitive impairment in 38.7%. More pronounced cognitive decline was more frequent in older patients, those with lower education levels, disease duration over 10 years, and the akinetic-rigid subtype of PD. Key predictors of dementia identified through regression analysis included: onset after age 60, disease duration exceeding 19 years, low educational attainment, and severe motor deficit. These findings highlight the importance of early detection and regular monitoring of cognitive functions to improve quality of life and slow disability progression in PD patients.

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