Emotional quotient in frontotemporal dementia vs. Alzheimer's disease: the role of socioemotional agnosia.

INTRODUCTION: Socioemotional dysfunction distinguishes behavioural variant frontotemporal dementia (bvFTD) from other dementias. Patients with bvFTD not only have early social impairment and emotional blunting, but they also have agnosia of their socioemotional dysfunction. METHODS: To investigate the relationship between agnosia and dysfunction, we assessed self-knowledge of socioemotional dysfunction with an emotional quotient (EQ) scale administered to 12 patients with bvFTD and a comparison group of 12 age-matched patients with Alzheimer's disease (AD), and compared these self-ratings to caregiver ratings of social dysfunction and emotional blunting. RESULTS: The bvFTD patients self-rated as having higher EQs than the AD patients, particularly higher self-ratings of their Social Skills, an EQ subscale which correlated with increased emotional blunting. On within-groups analysis, the bvFTD patients' high self-ratings of their EQ Appraisal of Emotions correlated with increased socioemotional dysfunction, whereas all of the AD patients' self-ratings correlated appropriately with their degree of dysfunction. CONCLUSIONS: Large socioemotional agnosia scores (EQ minus function) distinguishes bvFTD from AD. Additionally, in bvFTD, agnosia specifically for their ability to appreciate others' emotions correlates with the degree of socioemotional dysfunction, suggesting a role for socioemotional agnosia in increasing socioemotional dysfunction.

Somatic Symptom Disorder in Semantic Dementia: The Role of Alexisomia.

BACKGROUND: Semantic dementia (SD) is a neurodegenerative disorder characterized by loss of semantic knowledge. SD may be associated with somatic symptom disorder due to excessive preoccupation with unidentified somatic sensations. OBJECTIVE: To evaluate the frequency of somatic symptom disorder among patients with SD in comparison to comparably demented patients with Alzheimer׳s disease. METHODS: A retrospective cohort study was conducted using clinical data from a referral-based behavioral neurology program. Fifty-three patients with SD meeting criteria for imaging-supported semantic variant primary progressive aphasia (another term for SD) were compared with 125 patients with clinically probable Alzheimer disease. Logistic regression controlled for sex, age, disease duration, education, overall cognitive impairment, and depression. RESULTS: The prevalence of somatic symptom disorder was significantly higher among patients with SD (41.5%) compared to patients with Alzheimer disease (11.2%) (odds ratio = 6:1; p < 0.001). Somatic symptom disorder was associated with misidentification and preoccupation with normal bodily sensations such as hunger, bladder filling, borborygmi, rhinorrhea, and reflux; excessive concern over the incompletely understood meaning or source of pain or other symptoms; and Cotard syndrome or the delusion that unidentified somatic symptoms signify death or deterioration. CONCLUSIONS: SD, a disorder of semantic knowledge, is associated with somatic symptom disorder from impaired identification of somatic sensations. Their inability to read and name somatic sensations, or "alexisomia," results in disproportionate and persistent concern about somatic sensations with consequent significant disability.