Clinical characteristics with an impact on ADL functions of PD patients with cognitive impairment indicative of dementia
Dementia in Parkinson's disease (PD) is defined as cognitive decline severe enough to affect activities of daily living function (ADL). The aim of our exploratory study was to compare two groups of PD patients. Both groups had cognitive deficits severe enough to justify diagnosis of dementia, but they differed according to caregivers' rating on ADL dysfunction. Parameters which differed between the two groups were interpreted to affect the caregivers' perception of ADL dysfunction in PD patients with cognitive impairment indicative of Parkinson's disease dementia. Thirty of 131 Parkinson's disease patients fulfilled the Movement Disorders Society Task Force - recommended, cognitive Level-I-criteria for dementia. According to standardized caregiver ratings, volunteers were grouped into 18 patients with (ADL-) and 12 without instrumental activities of daily living dysfunction (ADL+). Caregiver activities of daily living function ratings closely correlated with self-estimates of patients and those of physician (p<0.001). ADL- patients performed worse on tests assessing visual-construction (p<0.05) and attention (p=0.03) than ADL+ patients. Moreover, the postural instability and gait disorder subtype was more frequent in ADL- patients (p=0.009). ADL- patients tended to have more communication problems (p=0.05), more anxiety (p=0.05) and showed a tendency to be treated more often with neuroleptics (p=0.049) than ADL+. Results indicate that worse attention, visual-construction abilities, the postural instability and gait disorder subtype, communication problems, medication and presence of anxiety are related to activities of daily living dysfunctions in Parkinson's disease patients with cognitive decline indicative of dementia. Our data suggests that not only cognitive factors but also non-cognitive factors seem to be linked to the diagnosis of Parkinson's disease dementia associated with significant impact on instrumental activities of daily living function. Further studies with larger sample sizes are needed to verify our results.