ICD-116D83	FRONTOTEMPORAL DEMENTIA (FTD) Frontotemporal dementia
ICD-10F02.0	Dementia in Pick disease
DSM-5-TRG31.09 + F02.8x	Major or Mild Neurocognitive Disorder Due to Frontotemporal Lobar Degeneration

1. Definition and nosology

Frontotemporal Dementia (FTD; ICD-11: 6D83; DSM-5-TR: G31.09 + F02.8x) — dementia developing from atrophy of the frontal and/or temporal lobes; typical onset between ages 45–65 (most common among early-onset dementias). Three clinical variants: bvFTD (behavioral variant) and two forms of PPA (Primary Progressive Aphasia — semantic and non-fluent).

2. History

• Pick A. (1892) — “Pick's disease” — description of frontotemporal atrophy.
• Neary D. et al. (1998) — FTD clinical consensus criteria.
• Rascovsky K. et al. (2011) — updated criteria for bvFTD.

3. Epidemiology

• 5–10% of dementia cases before age 65; Alzheimer's dominates after age 65.
• Sex: equal.
• Family history >40%.
• Comorbidity: ALS (Amyotrophic Lateral Sclerosis) — FTD-ALS spectrum (C9orf72 mutation).

4. Aetiology and pathogenesis

• Genetic (40%) — C9orf72 (most common), MAPT, GRN mutations.
• Pathology — tau (Pick body, MAPT), TDP-43 (TDP-43A, B, C, D, GRN, C9orf72), FUS proteins.

5. Clinical features

bvFTD (Behavioral Variant, ~60% of FTD)

• Early personality change — apathy, disinhibition, socially inappropriate behavior, loss of empathy.
• Stereotypical behavior (ritualistic).
• Hyperoral behavior (food changes, “sweet tooth”).
• Executive function significantly impaired; memory and visuo-spatial relatively preserved at onset.

PPA — Primary Progressive Aphasia

• Non-fluent variant (nfvPPA) — grammatical difficulty, slow speech, apraxia of speech.
• Semantic variant (svPPA) — loss of word meaning, agnosia; fluent, but empty speech.
• Logopenic — associated with Alzheimer's, distinct.

6. Diagnosis

6.1 Unified diagnostic criteria (Rascovsky 2011 bvFTD; Gorno-Tempini 2011 PPA)

bvFTD (Probable): ≥ 3 of 6 behavioral symptoms (disinhibition, apathy, loss of empathy, stereotypy, hyperorality, executive dysfunction) + functional impairment + neuroimaging support.

PPA: language is primary deficit; subvariant based on clinical and neuroimaging.

6.2 Source-specific clarifications

• Rascovsky K. et al. Brain 2011 — Behavioral Variant Frontotemporal Dementia.
• Gorno-Tempini M.L. et al. Neurology 2011 — PPA.

6.3 Diagnostic algorithm

1. Clinical interview + informant (behavioral change).
2. Neuropsychological battery (executive function, language).
3. Brain MRI — frontal and/or temporal atrophy.
4. FDG-PET — hypometabolism.
5. Genetic testing (family history).
6. ALS screening (clinical or electromyography).

6.4 Differential diagnosis

7. Examination and assessment

• FAB (Frontal Assessment Battery), neuropsychological.
• MRI, FDG-PET.
• Genetic test.
• ALS screening.

8. Treatment

1. There is no disease-modifying medication — treatment targeting the pathological process is not yet approved (clinical trials ongoing).
2. AChEI — ineffective or harmful in FTD (may worsen behaviour); unlike in Alzheimer's disease.
3. SSRI — for behavioral symptoms (disinhibition, compulsivity, depression) in bvFTD; some evidence.
4. Trazodone — for agitation; studies by Lebert F. et al.
5. Atypical antipsychotic — only in severe behavioral disturbance, short-term, FDA black box rule.
6. Carer support and psychoeducation critical (behavioral symptoms are difficult for the family).
7. Nutritional support (control in hyperoral behavior).
8. Legal-financial planning.

Source-specific specifications

• NICE NG97 — does not recommend AChEI for FTD.
• Lebert F. et al. Dement Geriatr Cogn Disord 2004 — trazodone.

Treatment methods

1. SSRI for bvFTD — Citalopram, sertraline — behavioral symptoms.
2. Trazodone — Agitation, sleep.
3. Non-Pharmacological — Environmental modification, structure, caregiver training.
4. Speech-Language Therapy (SLT) — For PPA; compensatory strategies.
5. Genetic Consultation — For family members.

9. Prognosis

• After diagnosis, median life expectancy is 6–11 years; FTD-ALS is shorter (3 years).
• Rapid decline with some mutations.

10. Myths and misconceptions

Myth 1: “FTD is a subtype of Alzheimer's”

Evidence: distinct pathological and clinical unit; tau, TDP-43, FUS pathologies; AChEI ineffective.

Myth 2: “AChEIs can be used in all dementias”

Evidence: AChEIs ineffective or harmful in FTD; NICE NG97 does not recommend.

Myth 3: “Behavioral change is only a psychiatric problem”

Evidence: Early onset behavioral change (45–65 years) should raise suspicion for FTD; neuroimaging is important.

Myth 4: “FTD is not genetic without a family history”

Evidence: 40% of cases have a family history; sporadic cases are also possible; C9orf72 expansion may be occult.

Myth 5: “The behavior of a patient with FTD is voluntary”

Evidence: behavioral alterations neurobiological — frontal lobe dysfunction; volitional control impaired.

11. Sources

1. WHO. ICD-11. 6D83 Dementia due to frontotemporal lobar degeneration. 2024.
2. APA. DSM-5-TR. 2022.
3. Rascovsky K. et al. Sensitivity of revised diagnostic criteria for the behavioural variant of frontotemporal dementia. Brain 2011;134(Pt 9):2456–2477.
4. Gorno-Tempini M.L. et al. Classification of primary progressive aphasia and its variants. Neurology 2011;76(11):1006–1014.
5. NICE NG97. 2018.
6. Lebert F. et al. Frontotemporal dementia: a randomised, controlled trial with trazodone. Dement Geriatr Cogn Disord 2004;17(4):355–359.