Frontotemporal Dementia Diagnosis and Characteristics

Clinical Presentation

• Frontotemporal dementia presents with progressive behavioral changes, language deficits, or both, typically beginning between ages 40-70 with an insidious onset and gradual progression over time 1, 2
• The American Academy of Neurology recommends considering frontotemporal dementia in patients with progressive behavioral changes or language deficits, with an age of onset between 40-70 years 1, 2

Core Behavioral Features

• Disinhibition, apathy/inertia, loss of sympathy/empathy, perseverative/compulsive behaviors, hyperorality, and dysexecutive profile are core features of behavioral variant frontotemporal dementia 1, 3
• The International Society for Frontotemporal Dementia recommends assessing for at least three of six core features for diagnosis of behavioral variant frontotemporal dementia 3

Critical Distinguishing Features from Psychiatric Disorders

• Key clinical indicators favoring frontotemporal dementia over primary psychiatric disorders include age of onset, insidious progressive course, impaired insight, and specific behavioral markers 1, 2
• The American Psychiatric Association notes that frontotemporal dementia can be distinguished from psychiatric disorders by its insidious onset, gradual progression, and presence of specific behavioral markers 1, 2

Associated Neurological Signs

• Parkinsonism, motor neuron disease features, alien limb phenomenon, and falls with vertical gaze palsy are associated neurological signs of frontotemporal dementia 1, 2, 4
• The Movement Disorder Society recommends assessing for parkinsonism and other associated neurological signs in patients with frontotemporal dementia 5

Assessment Tools

• The Frontal Behavioral Inventory (FBI) is a useful assessment tool for diagnosing behavioral variant frontotemporal dementia, with a score ≥12 on the positive subscale indicating bvFTD 4
• The American Academy of Neurology recommends using the FBI and other assessment tools to diagnose and monitor frontotemporal dementia 4

Neuroimaging Patterns

• Structural MRI findings, including frontal and anterior temporal lobe atrophy, are characteristic of frontotemporal dementia 9
• The American College of Radiology recommends using structural MRI and FDG-PET to diagnose and monitor frontotemporal dementia 9

Common Diagnostic Pitfalls

• The American Academy of Neurology recommends avoiding common diagnostic pitfalls, including dismissing diagnosis due to positive psychiatric history, relying on patient self-report, and missing diagnosis due to family psychiatric history 1, 2, 5
• The International Society for Frontotemporal Dementia notes that these pitfalls can lead to delayed or missed diagnosis of frontotemporal dementia 1, 2, 5