Facial Emotion Recognition Differentiates Behavioral Variant Frontotemporal Dementia From MDD
Due to overlapping symptoms in early variant frontotemporal dementia and major depressive disorder, a misdiagnosis often occurs.
Testing patients using a congruent and incongruent facial emotion intensity rating task comprised of anger, disgust, fear, sadness, surprise, and happiness enables clinicians to better discriminate between and diagnose behavioral variant frontotemporal dementia (bvFTD) and major depressive disorder (MDD), according to prospective findings from a study published in the Journal of Clinical Psychiatry.
Investigators enrolled patients meeting the Rascovsky diagnostic criteria for bvFTD (n=25), patients meeting Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria for MDD (n=20), patients meeting McKhann diagnostic criteria for Alzheimer's disease dementia (n=21), and healthy individuals (n=31). Participants were exposed to a facial stimulus a total of 6 times and were rated on its congruent emotion (eg, rating on sadness when a sad face was displayed), as well as its incongruent emotion on 5 emotions (anger, disgust, fear, surprise, and happiness when a sad face is displayed).
Participants with bvFTD exhibited significant confusion regarding negative facial emotions, often underrating congruent emotions (P <.01) and overrating incongruent emotions (P <.001). In addition, participants with MDD significantly overrated congruent negative facial emotions (P <.001). Congruent and incongruent emotional ratings were deemed highly discriminatory between bvFTD and MDD (area under the curve [AUC] =93% to 98%). When investigators contrasted the congruent and incongruent rating types, ratings exhibited nearly 100% discrimination between the two disorders (AUC=99%). Participants with Alzheimer's disease dementia demonstrated similar congruent emotion ratings as the healthy control group.
Many of the patients with MDD exhibited clear, visible signs of depression, which likely limited the value of the discriminatory tests in this study. In addition, since the investigators were unable to determine the cause of bvFTD, it's possible that some of the participants with bvFTD due to causes unrelated to frontotemporal lobar degeneration pathologies.
In this small sample of patients with bvFTD and MDD, a simple emotion intensity rating task may be “well suited for a fine-grained assessment of emotion perception in clinical routine, both for diagnostic purposes and for follow-up assessments.”
Chiu I, Piguet O, Diehl-Schmid J, et al. Facial emotion recognition performance differentiates between behavioral variant frontotemporal dementia and major depressive disorder. J Clin Psychiatry. 2018;79(1).