Objective: Disorders of executive functions are among the most frequent cognitive deficits, but they remain poorly defined and are subject to heterogeneous assessment. To address this major issue, the Groupe de Réflexion sur l'Evaluation des Fonctions Exécutives (GREFEX) group has proposed criteria for behavioral and cognitive dysexecutive syndromes and has designed a battery including a specific heteroquestionnaire and 7 cognitive tests. We investigated the frequency of behavioral and cognitive dysexecutive disorders in patients suffering from various diseases and the association of these disorders with loss of autonomy.
Methods: A total of 461 patients aged between 16 and 90 years with severe traumatic brain injury, stroke, mild cognitive impairment, Alzheimer disease, multiple sclerosis, and Parkinson disease were recruited into this prospective cohort study by 21 centers between September 2003 and June 2006. Behavioral and cognitive dysexecutive disorders were examined using the GREFEX battery.
Results: A dysexecutive syndrome was observed in 60% of patients, concerning both behavioral and cognitive domains in 26% and dissociated in 34%. All behavioral and cognitive dysexecutive disorders discriminated (p = 0.001, all) patients from controls. The pattern of cognitive syndrome differed (p = 0.0001) according to the disease. Finally, behavioral (odds ratio [OR], 4.6; 95% confidence interval [CI], 2. 3-9.1; p = 0.0001) and cognitive (OR, 3.36; 95% CI, 1.7-6.6; p = 0.001) dysexecutive syndromes and Mini Mental State Examination score (OR, 0.79; 95% CI, 0.68-0.91; p = 0.002) were independent predictors of loss of autonomy.
Interpretation: This study provided criteria of dysexecutive syndrome and showed that both behavioral and cognitive syndromes contribute to loss of autonomy. Profiles vary across patients and diseases, and therefore systematic assessment of behavioral and cognitive disorders in reference to diagnostic criteria is needed.