Quantifying activities of daily living impairment in Parkinson’s disease using the Functional Activities Questionnaire

Objective Cognitive-driven activity of daily living (ADL) impairment in Parkinson’s disease (PD) is increasingly discussed
as prodromal marker for dementia. Diagnostic properties of assessments for this specifc ADL impairment are sparsely
investigated in PD. The ability of the Functional Activities Questionnaire (FAQ) for diferentiating between PD patients with
normal cognition and with mild cognitive impairment (PD-MCI), according to informant and self-reports, was examined.
Global cognitive function in groups with and without mild ADL impairment was compared according to diferent cut-ofs.
Methods Multicenter data of 589 patients of an international cohort (CENTRE-PD) were analyzed. Analyses were run separately for informant-rated and self-rated FAQ. Receiver operating characteristic (ROC) analysis was conducted to defne the
optimal FAQ cut-of for PD-MCI (≥1), and groups were additionally split according to reported FAQ cut-ofs for PD-MCI
in the literature (≥3,≥5). Binary logistic regressions examined the efect of the Montreal Cognitive Assessment (MoCA)
score in PD patients with and without mild ADL impairment.
Results Two hundred and twenty-fve (38.2%) patients were classifed as PD-MCI. For all three cut-of values, sensitivity
was moderate to low (<0.55), but specifcity was moderately high (>0.54) with a tendency of higher values for self-reported
defcits. For the self-report, the cut-of≥3 showed a signifcant efect of the MoCA (B= −0.31, p=0.003), where FAQ≥3
patients had worse cognition. No efect for group diferences based on informant ratings was detected.
Conclusion Our data argue that self-reported ADL impairments assessed by the FAQ show a relation to the severity of
cognitive impairment in PD.