A - 26 Behavioral Variant Alzheimer's Disease: Distinctly Different from Alzheimer's Disease and Behavioral Variant Frontotemporal Disease.

OBJECTIVE: Behavioral variant Alzheimer's disease (bvAD) is a variant of Alzheimer's disease (ad) and is distinctly different from behavioral variant frontotemporal disease (bvFTD). However, bvAD has many overlapping symptoms with ad (i.e., atrophy in temporal, episodic memory deficits) and bvFTD (i.e., behavioral changes, early onset, caregiver burden) that can cause diagnostic confusion.

METHOD: Patient was referred to outpatient tertiary neuropsychological clinic for neuropsychological evaluation. Patient was a 75-year-old, right-handed, retired Caucasian man with 18 years of formal education. He reported experiencing insidious and gradual memory loss over the last eight years. He had been previously diagnosed with ad, mild cognitive impairment due to cerebrovascular disease, and suspected frontotemporal disease by three different providers. CT scan received small vessel ischemic disease and PET scan showed hypometabolism in the bilateral anterior temporal lobes. His symptoms included difficulties with memory, attention, language, executive functioning, disinhibition, impulsivity, uncontrollable crying, and apathy.

RESULTS: Neuropsychological testing results revealed primary deficits in memory and executive functioning. He presented with an amnestic memory profile, with reduced encoding of new information and significantly impaired consolidation and retrieval. He demonstrated difficulty with working memory, inhibition, set-shifting, problem-solving, and visuoconstruction. Repetition and naming were reduced. All other cognition was largely intact.

CONCLUSIONS: The presenting case analysis illustrates the unique presentation of bvAD when considering an ad versus bvFTD diagnosis, specifically in the context of behavioral/personality changes and memory deficits. Specifically, it draws important attention to the cognitive profile of bvAD, which can be often overlooked and lead providers to incorrect diagnoses, thus delaying proper treatment.