Although impaired insight is a core diagnostic criterion for establishing the diagnosis of frontotemporal dementia (FTD), insight has rarely been studied in amyotrophic lateral sclerosis (ALS).
Objective: To determine differences between patient and informant (caregiver) reports of behavior and behavioral change in amyotrophic lateral sclerosis.
Methods: Behavioral data for 17 patients with ALS and 4 patients with ALS-FTD were analyzed. Behavioral changes were evaluated using the Frontal Systems Behavior Scale (FrSBe). We compared premorbid to current behavioral profiles and patient self-reports with those of their informants to determine the level of awareness regarding behavioral changes since the onset of ALS.
Results: ALS patients without FTD had normal insight, as defined by this study, although self-reports suggested mild behavioral abnormalities. In contrast, patients with ALS-FTD revealed a marked loss of insight regarding profound changes in behavior.
Conclusions: Patients with ALS-FTD exhibit a profound lack of insight, which is not found in non-demented ALS patients. Patients without dementia have normal insight, although they report mild behavioral changes that might reflect a psychological response to the disease.