bvFTD

Behavioral variant frontotemporal dementia (bvFTD) is a clinical syndrome within the frontotemporal dementias characterized by prominent changes in personality and behavior due to degeneration of the frontal and anterior temporal lobes. It commonly presents in middle adulthood, often in the 40s to 60s, with variability in onset and progression.

Core features include disinhibition or socially inappropriate behavior, apathy or inertia, diminished empathy or social awareness, perseverative or compulsive behaviors, and hyperorality or dietary changes. Executive dysfunction is prominent, and functional impairment progresses as the disease advances. The presentation can be heterogeneous, and psychiatric conditions may be misdiagnosed early in the course.

Neuroimaging typically shows focal or asymmetric atrophy of the frontal lobes, sometimes extending to the anterior temporal regions. Metabolic imaging may reveal hypometabolism in affected areas. Pathologically, bvFTD is linked to several proteinopathies, most commonly tau or TDP-43 inclusions, and less often FUS. Familial cases are associated with genetic mutations in MAPT, GRN, or C9orf72, among others.

Diagnosis is clinical, based on established criteria, and is supported by imaging findings and, when available, biomarkers. Differential diagnosis includes Alzheimer's disease, other dementias, and primary psychiatric disorders. There is no disease-modifying treatment; management focuses on symptom relief, safety planning, and caregiver support. Pharmacologic options, such as selective serotonin reuptake inhibitors, may help behavioral symptoms, while antipsychotics are used with caution due to potential adverse effects. Prognosis is progressive, with a typical course spanning several years and substantial variability in survival and functional decline.