Instruction: In Parkinson's disease (PD), activities of daily living (ADL) impairments are crucial for diagnosis of dementia (PDD). Performance-based tests are promising tools to discriminate between different levels of cognitive impairment in PD; however, the value of those tests for diagnosis of PDD is only sparsely investigated. Therefore, we evaluated the Erlangen Test of Activities of Daily Living (E-ADL), a time-efficient performance-based ADL test, in PD.
Method: In this cross-sectional study, 40 PD patients with normal cognition (PD-NC), 45 patients with mild cognitive impairment (PD-MCI) and 21 patients with PDD were assessed with a comprehensive ADL and cognitive test battery.
Results: Interrater reliability (rs =.86) indicated high consistency of the standardized E-ADL scoring system between raters. The E-ADL correlated significantly with other tests of ADL functions (p <.01), highest with an alternative performance-based ADL test (rs = -.52), and lowest with self-ratings and a physician-rated scale. The E-ADL was also associated with cognitive impairment (p <.01), but also with motor impairment. A binary logistic regression model verified that the E-ADL (p =.04) was an independent predictor of PDD, in addition to motor impairment explaining 53.3% of variance. Receiver operating characteristic curve analysis of the E-ADL revealed an area under the curve of 0.78, a specificity of 77%, and a sensitivity of 67% for diagnosis PDD.
Conclusions: The standardized, easy, and quick to administer E-ADL showed acceptable levels of reliability, and validity in PD and measures cognitive-driven ADL functions. Therefore, it might be a suitable test to support diagnosis of PDD in the clinical daily routine.
Keywords: Parkinson’s disease; activities of daily living; cognition; dementia; performance-based assessment.