Objective: To investigate the effects of attentional deficits on activities of daily living (ADL) in patients with dementia associated with Parkinson's disease (PDD).
Method: 461 patients were assessed neuropsychologically. Factor analyses were used to differentiate attention from other cognitive functions and to differentiate different aspects of ADL functions. The effects of the attentional measure on ADL were examined using sequential multiple regression, controlling for age, sex, education, severity of motor symptoms and other cognitive functions.
Results: Three cognitive factors were identified, with one factor emerging as a measure of vigilance and focused attention. This factor predicted different aspects of ADL status even after controlling for motor functions and other cognitive factors. The attention factor was the single strongest cognitive predictor of ADL status, matching the strength of the effects of motor functions on ADL status.
Conclusion: Impaired attention is an important determinant of ADL functions in patients with PDD.