The relationships between apathy and executive dysfunction in multiple sclerosis

Neuropsychiatric symptoms are common in multiple sclerosis (MS). Among these, apathy is relatively frequent but its relationships with cognitive dysfunctions have been poorly investigated.

To explore cognitive correlates of apathy with or without depression ("pure apathy") in MS patients.

Nondemented MS patients (n = 125), consecutively referred to the Multiple Sclerosis Center of Moscati Hospital, in Avellino, Italy, underwent the Apathy Evaluation Scale Self-Rated (AES-S), the Hamilton Depression Rating Scale (HDRS), and a comprehensive neuropsychological battery.

According to cut-off scores of AES-S (≥36), of HDRS (≥15) and criteria for diagnosis of apathy and major depression, the sample was divided into 4 subgroups: 49 patients without apathy or depression (A-D-), 20 patients with "pure" apathy (A+D-), 29 patients with depression only (A-D+), and 27 patients with apathy and depression (A+D+). Cognitive performance significantly differed in the 4 groups: in particular MS patients with apathy (A+D- and A+D+) performed significantly worse on executive tasks than patients without apathy, whereas patients with "pure" apathy (A+D-) performed significantly worse than patients without apathy only on executive tasks tapping cognitive control abilities.

We found a significant relationship between apathy and dysexecutive defects in MS, consistent with the hypothesis that dysfunctions of prefrontal cortico-subcortical circuits contribute to specific neuropsychiatric syndromes in MS patients. (PsycINFO Database Record