Early diagnosis of behavioral variant of frontotemporal dementia – a clinical perspective

The behavioral variant of frontotemporal dementia, part of the frontotemporal lobar degeneration spectrum, is a rare disease with rapid progression. The clinical manifestation of this disease is not homogeneous, which is an additional difficulty. Usually, the patient’s age, the presence of nonspecific cognitive disorders or behavioral problems lead to ignoring the suspicion of dementia. Half of the patients with the behavioral variant of frontotemporal dementia are misdiagnosed at the first examination, most often in psychiatric disease. Despite diagnostic criteria for the behavioral variant of frontotemporal dementia for over a decade, most specialists are unfamiliar with them. It also applies to the latest recommendations for neurocognitive frontotemporal disorders.

Another problem is the lack of diagnostic tools and the need of expensive and less available tests or consultations. It results in obtaining a diagnosis far away from the onset of the first symptoms. Moreover, due to the rapid progression of the disease, the advancement of the patient’s condition sometimes makes it impossible to make a proper diagnosis. The article discusses the usefulness of screening, neuropsychological examination with social cognition, neurological, genetic, biomarker, and neuroimaging tests in diagnosing the behavioral variant of frontotemporal dementia in terms of the diagnostic criteria and recommendations. The most crucial role in the early diagnosis is a specific interview concerning the familial nature of behavioral disorders and/or psychiatric diseases, with typical and atypical symptoms. It helps differentiate the behavioral variant of frontotemporal dementia from other types of dementia, psychiatric diseases, and other potential causes of the patient’s problems.