Confirming FTD (Diagnostic Criteria)
An international consortium of experts agreed upon these diagnostic criteria for behavioral variant frontotemporal dementia (bvFTD) in 2010. These criteria employ three levels of diagnostic certainty: possible, probable and definite. The criteria must be met as defined without meeting any of the exclusion criteria.
- Shows progressive deterioration of behavior and/or cognition by observation or history (as provided by a knowledgeable informant)
Three of the following behavioral/cognitive symptoms must be present to meet criteria. These symptoms should occur repeatedly, not just as a single instance.
Early behavioral disinhibition (one of the following must be present)
- Socially inappropriate behavior: touching or kissing strangers, inappropriate sexual acts, public urination, criminal behavior, etc.
- Loss of manners or decorum: examples include
- crude or sexually explicit remarks, jokes or opinions which may be offensive to others;
- lack of response to social cues (e.g., will continue talking despite other’s attempts to end a conversation);
- physical behaviors such as flatulence, touching private body parts, belching or spitting;
- poor hygiene or grooming (malodorous, stained, torn or inappropriate clothing),
- loss of respect for interpersonal space
- Impulsive, rash or careless actions: impulsive behaviors which may or may not be performed in a social context (e.g., new- onset gambling, taking things, stealing (usually food or visually stimulating objects), buying or selling property without regard for consequences)
- Early apathy or inertia (one of the following must be present)
- Apathy: loss of interest, drive or motivation (e.g., passivity, lack of spontaneity, does not engage in previously rewarding activities)
- Inertia: decreased initiation of behavior (e.g., needs prompting to initiate or continue routine activities, less likely to initiate or sustain conversations)
- Early loss of sympathy or empathy (one of the following must be present)
- Diminished response to other people’s needs and feelings: positive rating of this feature should be based on specific examples that reflect a lack of understanding or indifference to other people’s feelings – e.g., hurtful comments, disregard for other’s pain or distress, making inappropriate jokes
- Diminished social interest, interrelatedness or personal warmth: general decrease in social engagement (coldness, lack of eye contact, etc.)
- Early perseverative, stereotyped or compulsive/ritualistic behavior (one of the following must be present)
- Simple repetitive movements: tapping, clapping, rubbing, scratching, picking at skin or clothing, pursing lips, lip smacking, etc.
- Complex, compulsive or ritualistic behaviors: counting and cleaning rituals, collecting, checking, repetitive trips to the bathroom, ordering objects, walking fixed routes, etc.
- Stereotypy of speech: repeating words or phrases that have no communicative value
- Hyperorality and dietary changes (one of the following must be present)
- Altered food preferences: carbohydrate craving (particularly sweets) or food fads
- Binge eating, increased consumption of alcohol or cigarettes: patient continues to eat despite satiety (weight gain ____ lb); compulsive smoking, chewing tobacco or gum; or alcohol ingestion
- Oral exploration or consumption of inedible objects
- Neuropsychological profile: executive/generation deficits with relative sparing of memory and visuospatial functions (all of the following must be present)
- Deficits in executive tasks: Trails-B, generation tasks (letter fluency/design fluency) or presence of errors (e.g., perseverations or rule violations)
- Relative sparing of episodic memory
- Relative sparing of visuospatial skills e.g., ability to copy simple line drawings
- Meets criteria for possible bvFTD
- Exhibits significant functional decline (by caregiver report or as evidenced by CDR or FAQ scores)
- Imaging results consistent with bvFTD (one of the following must be present)
- Frontal and/or temporal atrophy on CT or MRI (Disproportionate atrophy in frontal and/or anterior temporal regions)
- Frontal hypoperfusion or hypometabolism on SPECT or PET (Disproportionate frontal or frontotemporal hypometabolism or hypoperfusion)
bvFTD with Definite FTLD Pathology
- Meets criteria for possible or probable bvFTD
- Meets one of the following
- Histopathological evidence of FTLD on biopsy or at post-mortem e.g., FTLD-tau, FTLD-TDP, FTLD-UPS, FTLD-IF, FTLD-ni, BIBD
- Presence of a known pathogenic mutation e.g., MAPT, PGRN, CHMP2B, VCP
Exclusion Criteria for bvFTD
Criteria 1 and 2 must both be answered negatively for any bvFTD diagnosis. Criterion 3 can be positive for possible bvFTD but must be negative for probable bvFTD.
- Pattern of deficits is better accounted for by other non-degenerative nervous system or medical disorders (excludes all bvFTD diagnoses) e.g., delirium, cerebrovascular disease, cerebellar disorder, systemic disorders (e.g., hypothyroidism) or substance-induced conditions
- Behavioral disturbance is better accounted for by a psychiatric diagnosis (excludes all bvFTD diagnoses) e.g., depression, bipolar disorder, schizophrenia, pre-existing personality disorder
- Biomarkers strongly indicative of Alzheimer’s disease or other neurodegenerative process (excludes diagnosis of probable bvFTD) e.g., genetic mutations, extensive PIB binding, CSF markers