Late life bipolar disorder evolving into frontotemporal dementia mimic

OBJECTIVES: Although bipolar disorder has been understood classically as a cyclic disease with full recovery between mood episodes, in the last decade, evidence has accumulated supporting progressive features. The clinical picture of advanced or end-stage bipolar disorder is heterogeneous with possible deficits in cognition and behavior, as illustrated by our case series. CASES: From our neuropsychiatric outpatient clinic, we describe four cases with bipolar disorder gradually developing a clinical syndrome, including apathy, disinhibition, loss of empathy, stereotypical behavior, and compulsiveness, fulfilling the criteria for possible behavioral variant frontotemporal dementia. All cases were diagnosed with bipolar 1 disorder at least 10 years before the onset of the current symptoms, which were not due to recent mood episodes or switches of medication. In all cases, 3-7 years of follow-up yielded no progression. Repeated neuroimaging was within normal limits. Cerebrospinal fluid biomarker studies were not supportive of underlying neurodegenerative pathology. C9orf72 mutation status was negative in all cases. CONCLUSION: Symptoms fitting the criteria for possible behavioral variant frontotemporal dementia may be present in end-stage of bipolar disorder. An alternative neurodegenerative nature seems unlikely based on repeated normal neuroimaging and the absence of clinical progression. Functional involvement of the frontal-subcortical networks might play a role

Social Cognition Differentiates Behavioral Variant Frontotemporal Dementia From Other Neurodegenerative Diseases and Psychiatric Disorders

Objective: Although deficits in social cognition are established as core features in behavioral variant frontotemporal dementia (bvFTD), it remains unresolved if impaired social cognition distinguishes bvFTD from the broad differential diagnoses in clinical practice. Our aim was to study whether social cognition discriminates bvFTD from other neurodegenerative diseases and psychiatric disorders in patients presenting with late-onset frontal symptoms. Next, we studied the association of social cognition with frontal symptoms and cognitive functioning. Methods: In this longitudinal multicenter study, besides clinical rating scales for frontal symptoms, social cognition was determined by Ekman 60 Faces test and Faux Pas in addition to neuropsychological tests for other cognitive domains in patients with probable and definite bvFTD (N = 22), other neurodegenerative diseases (N = 24), and psychiatric disorders (N = 33). Median symptom duration was 2.8 years, and patients were prospectively followed over 2 years. Results: Total scores from Ekman 60 Faces test were significantly lower in bvFTD than in other neurodegenerative diseases and psychiatric disorders. Ekman 60 Faces test explained 91.2% of the variance of psychiatric disorders and other neurodegenerative diseases versus bvFTD (χ2 = 11.02, df = 1, p = 0.001) and was associated with all other cognitive domains. Faux Pas and the other cognitive domains did not differ between these diagnostic groups. Conclusion: In this clinical sample Ekman 60 Faces test distinguished bvFTD successfully from other neurodegenerative diseases and psychiatric disorders. Although associated with social cognition, other cognitive domains were not discriminative. This study provides arguments to add the Ekman 60 Faces test to the neuropsychological examination in the diagnostic procedure of bvFTD

Gedragsverandering als symptoom

Behavioural variant frontotemporal dementia (bvFTD) is a neurodegenerative disease, the symptoms of which are changes in character, behavioural changes and socio-cognitive changes occurring predominantly at an age between 40 and 70 years. Frontotemporal atrophy is apparent on diagnostic imaging in 70% of patients with bvFTD; a diagnostic dilemma arises if this is not clearly obvious. Validated questionnaires for stereotypical behaviour, depressive symptoms and apathy, and neuropsychological examination can be very helpful in differentiating between bvFTD and psychiatric and other neurological conditions. A brain MRI is always indicated in patients displaying behavioural changes; frontal or temporal atrophy on brain MRI provide sufficient support for the diagnosis 'probable bvFTD'. When in doubt, a supplementary 18F-FDG-PET scan can be performed, but hypometabolism on an 18F-FDG-PET scan can give a false-positive result. If bvFTD is suspected, a multidisciplinary approach, clinical follow-up for 2 years and referral to an FTD centre of excellence are recommended. Conflict of interest and financial support: none declared

Diagnostic Instability Over Time in the Late-Onset Frontal Lobe Syndrome: When Can We Say it's FTD?

Objectives: Distinguishing sporadic behavioral variant of frontotemporal dementia (bvFTD) from late-onset primary psychiatric disorders (PPD) remains challenging with the lack of robust biomarkers. An early bvFTD misdiagnosis in PPD cases and vice-versa is common. Little is known about diagnostic (in)stability over longer period of time. We investigated diagnostic instability in a neuropsychiatric cohort up to 8 years after baseline visit and identified which clinical hallmarks contribute to diagnostic instability. Design: Diagnoses of participants of the late-onset frontal lobe (LOF) study were collected from the baseline visit (T0) and the 2-year follow-up visit (T2). Clinical outcomes were retrieved 5–8 years after baseline visit (Tfinal). Endpoint diagnoses were categorized into bvFTD, PPD and other neurological disorders (OND). We calculated the total amount of participants that switched diagnosis between T0-T2 and T2-Tfinal. Clinical records of participants that switched diagnosis were assessed. Results: Of the 137 patients that were included in the study, the final diagnoses at Tfinal were bvFTD 24.1% (n = 33), PPD 39.4% (n = 54), OND 33.6% (n = 46) and unknown 2.9% (n = 4). Between T0 and T2, a total of 29 (21.2%) patients switched diagnosis. Between T2 and Tfinal, 8 (5.8%) patients switched diagnosis. Prolonged follow-up identified few cases with diagnostic instability. Major contributors to diagnostic instability where a nonconverting diagnosis of possible bvFTD and a probable bvFTD diagnosis based on informant-based history and an abnormal FDG-PET scan whilst having a normal MRI. Conclusion: Considering these lessons, a FTD diagnosis remains stable enough to conclude that 2 years is sufficient to say if a patient with late-life behavioral disorder has FTD

Psychosis in behavioral variant frontotemporal dementia

Background: Dementia is generally characterized by cognitive impairment that can be accompanied by psychotic symptoms; for example, visual hallucinations are a core feature of dementia with Lewy bodies, and delusions are often seen in Alzheimer’s disease. However, for behavioral variant of frontotemporal dementia (bvFTD), studies on the broad spectrum of psychotic symptoms are still lacking. The aim of this study was to systematically and prospectively subtype the wide spectrum of psychotic symptoms in probable and definite bvFTD. Methods: In this study, a commonly used and validated clinical scale that quantifies the broad spectrum of psychotic symptoms (Positive and Negative Symptom Scale) was used in patients with probable and definite bvFTD (n=22) and with a primary psychiatric disorder (n=35) in a late-onset frontal lobe cohort. Median symptom duration was 2.8 years, and the patients were prospectively followed for 2 years. Results: In total, 22.7% of bvFTD patients suffered from delusions, hallucinatory behavior, and suspiciousness, although the majority of the patients exhibited negative psychotic symptoms such as social and emotional withdrawal and blunted affect (95.5%) and formal thought disorders (81.8%). “Difficulty in abstract thinking” and “stereotypical thinking” (formal thought disorders) differentiated bvFTD from psychiatric disorders. The combined predictors difficulty in abstract thinking, stereotypical thinking, “anxiety”, “guilt feelings,” and “tension” explained 75.4% of variance in the diagnosis of bvFTD versus psychiatric diagnoses (P<0.001). Conclusion: Delusions, hallucinatory behavior, and suspiciousness were present in one-fifth of bvFTD patients, whereas negative psychotic symptoms such as social and emotional withdrawal, blunted affect, and formal thought disorders were more frequently present. This suggests that negative psychotic symptoms and formal thought disorders have an important role in the psychiatric misdiagnosis in bvFTD; misdiagnosis in bvFTD might be reduced by systematically exploring the broad spectrum of psychiatric symptoms

The diagnostic challenge of y the y Late-onset frontal lobe syndrome: Clinical predictors for primary psychiatric disorders versus behavioral variant frontotemporal dementia

Objective: Primary psychiatric disorders (PsD) can present with symptomatology identical to that of behavioral variant frontotemporal dementia (bvFTD). To date, clinical guidelines do not provide a solution for this diagnostic challenge. The aim of our study was to prospectively determine which demographic, clinical, neuropsychological, neuroimaging, and cerebrospinal fluid biomarkers are important in distinguishing PsD from bvFTD. Methods: Patients with late-onset behavioral disturbances (aged 45–75 years, 73% male) were included based on their scores on the Frontal Behavioral Inventory and the Stereotypy Rating Inventory and followed for 2 years from April 2011 to June 2015. Odds ratios (ORs) were calculated with backward stepwise logistic regression analyses to investigate the association between baseline clinical and demographic variables and the 2-year follow-up diagnosis of PsD (n = 46) (DSM-IV) versus probable/definite bvFTD (n = 27) (International Behavioral Variant FTD Criteria Consortium criteria). We separately measured the association between additional investigations and the 2-year followup diagnosis. Finally, we combined the selected variables to measure the predictive value of both clinical and additional investigations in a single model. Results: Male gender (OR = 5.9; 95% CI, 1.3–26.0), less stereotypy (OR = 0.08; 95% CI, 0.02–0.34), and more depressive symptoms (OR = 1.13; 95% CI, 1.04–1.24) explained 49% of the variance predicting PsD versus bvFTD (χ2 3 = 29.4, P< .001) and correctly classified 82.1% of the cases. Neuroimaging (OR = 0.02; 95% CI, 0.002–0.123) explained 55% of the variance (χ2 1 = 37.5, P< .001) and, in combination with clinical variables, 66.1% of the variance (χ2 3 = 44.06, P< .001). Conclusions: The present study demonstrated that PsD can be distinguished from probable/definite bvFTD with a thorough clinical evaluation by a psychiatrist and neurologist along with use of validated questionnaires for depression and stereotypy; these measures are even more effective in combination with neuroimaging