Subjective and objective assessment of executive functions in Parkinson's disease.

Impairments in executive functions (EF) in Parkinson's disease (PD) will have a negative influence on daily life. For the assessment objective and subjective measurement approaches are used. It is however unknown whether these approaches contribute in a different way to the assessment of EF in PD. Thirty-nine PD patients and 24 healthy participants completed the Dysexecutive questionnaire (DEX; subjective measure) and the Frontal Assessment Battery (FAB; objective measure). PD patients showed impaired EF (FAB) and reported more problems with EF in daily life (DEX) than healthy participants. The performance on the FAB could however not be explained by the problems with EF that were reported by PD patients (DEX) and vice versa. In conclusion, not all PD patients who show impairments in EF report them and not all PD patients who report problems with EF in daily life show impairments according to objective measurement. Both measures thus contribute in a different way to the assessment of EF in PD patients. However, it has to be considered that the FAB is not a critical test to assess cognition in PD, since these patients also suffer from posterior abnormalities including memory and visuo-spatial deficits which are strong predictors for PD dementia.