Utility of empathy informant report in FTD differential diagnosis

Loss of empathy is a hallmark feature of behavioral variant frontotemporal dementia (bvFTD). Change in socioemotional functioning identified by others is often the primary initial presenting concern in this disorder, in contrast to more subtle early cognitive changes and limited patient insight. The present study examined the predictive utility of an empathy informant-report measure for discriminating clinician-diagnosed bvFTD from other dementia syndromes.

Data from the National Alzheimer's Coordinating Center (NACC) database were used to study individuals with bvFTD (n = 406) and other dementia syndromes (n = 385). Participants were administered neuropsychological measures and collateral informants completed an informant-report of empathy.

Informants reported that patients with bvFTD demonstrated significantly lower levels of empathic concern [F(1, 789) = 120.91, p < .001, η² = 0.13] and perspective taking [F(1, 789) = 153.08, p < .001, η² = 0.16] than patients with other dementia syndromes. These differences were not attributable to the level of global cognitive impairment. Empathy scores were not significantly associated with any neurocognitive measure when controlling for age. ROC curve analyses showed fair to good clinical utility of the informant-report empathy measure for distinguishing bvFTD from non-bvFTD, whereas a traditional measure of executive functioning failed to differentiate the groups.

These findings indicate that informant ratings of empathy offer a unique source of clinical information that may be useful in detecting neurobehavioral changes specific to bvFTD before a clear neurocognitive pattern emerges on testing.