Frontotemporal dementia

Validity of screening tools for dementia and mild cognitive impairment among the elderly in primary health care: a systematic review

OBJECTIVES

This systematic review aims to provide updated and comprehensive evidence on the validity and feasibility of screening tools for mild cognitive impairment (MCI) and dementia among the elderly at primary healthcare level.

STUDY DESIGN

A review of articles was performed.

METHODS

A search strategy was used by using electronic bibliographic databases including PubMed, Embase and CENTRAL for published studies and reference list of published studies. The articles were exported to a bibliographic database for further screening process. Two reviewers worked independently to screen results and extract data from the included studies. Any discrepancies were resolved and confirmed by the consensus of all authors.

RESULTS

There were three screening approaches for detecting MCI and dementia - screening by a healthcare provider, screening by a self-administered questionnaire and caretaker informant screening. Montreal Cognitive Assessment (MoCA) was the most common and preferable tool for MCI screening (sensitivity [Sn]: 81-97%; specificity [Sp]: 60-86%), whereas Addenbrooke's Cognitive Examination (ACE) was the preferable tool for dementia screening (Sn: 79-100%; Sp: 86%).

CONCLUSION

This systematic review found that there are three screening approaches for detecting early dementia and MCI at primary health care. ACE and MoCA are recommended tools for screening of dementia and MCI, respectively.

Oxytocin for frontotemporal dementia: a systematic review

BACKGROUND

The aim of this systematic review is to identify published randomized controlled trials (RCTs) that evaluated the use of oxytocin in individuals with frontotemporal dementia (FTD).

METHODS

A literature search was conducted of PubMed, MEDLINE, EMBASE, PsycINFO and Cochrane collaboration databases for RCTs in any language that evaluated the use of oxytocin in individuals with FTD. Bibliographic databases of published articles were also searched for additional studies.

RESULTS

A total of two RCTs that evaluated the use of oxytocin in individuals with FTD were identified. In one study, the use of oxytocin in individuals with FTD produced a reduction in identification of negative facial expressions (anger and fear) which can be hypothesized to improve trust and increase cooperation in these individuals. Both studies noted oxytocin was well tolerated and showed short term benefits on behavioral symptoms in individuals with FTD.

CONCLUSIONS

Oxytocin appears to improve social aspects of cognition and behavioral symptoms in individuals with FTD and is well tolerated. However, positive data from larger and longer duration RCTs are needed before the routine use of oxytocin in individuals with FTD can be recommended.

Cognitive impairment in older adults and oral health considerations: treatment and management

Worldwide incidences of degenerative cognitive diseases are increasing as the population ages. This decline in mental function frequently causes behavioral changes that directly affect oral health. The loss of interest and ability to complete the simple tasks of brushing and flossing can cause a rapid development of hard and soft tissue diseases that result in decreased function and increased dental pain. The challenge for the dental community is to understand and to identify the early signs of cognitive dysfunction so as to develop a rational treatment strategy that allows patients to comfortably maintain their teeth for as long as possible.

Pharmacological treatments for frontotemporal dementias: a systematic review of randomized controlled trials

The objective of this review is to summarize the current data on the pharmacological treatments for frontotemporal dementias from randomized controlled trials. A systematic search of 4 major databases, PubMed, Medline, PsychINFO and Cochrane, found a total of 9 randomized controlled, double-blinded clinical trials. Of these, 2 trials used the selective serotonin reuptake inhibitor (SSRI), paroxetine; 1 trial used trazodone; 2 trials used stimulants (methylphenidate and dextroamphetamine); 1 trial used the acetylcholinesterase inhibitor, galantamine; 2 trials used the N-methyl-d-aspartate antagonist, memantine; and 1 trial used the neuropeptide oxytocin. The analysis of the available data indicates that SSRIs, trazodone, and the amphetamines may be effective in reducing some behavioral symptoms, but none of these medications had an impact on cognition. Available data indicate that these medications were well tolerated in all the trials.

Asymmetric cortical degenerative syndromes: an integrated approach to clinical and imaging review

BACKGROUND

The term asymmetric cortical degenerative syndromes (ACDSs) refers to any brain afflictions that result in selective atrophy, particularly with an asymmetric pattern. Regardless of the etiology, the resulting compromised profile reflects the affected topography, which correlates with the clinical findings, more than any specific neuropathologic entity.

REVIEW SUMMARY

ACDS can represent a diagnostic challenge, because of an overlap of clinical manifestations, especially in the early stages. Magnetic resonance techniques are useful to understand nuclear medicine studies and to confirm areas of focal atrophy by providing anatomic details and allowing an accurate correlation with several different clinical settings.

CONCLUSIONS

This article demonstrates a practical neuroradiologic approach for ACDS, including optimized imaging analysis (magnetic resonance and nuclear medicine studies), which correlates their patterns with clinical and pathologic findings of the most relevant disorders.

The spectrum of recurrent thoughts and behaviors in frontotemporal dementia

This article describes the spectrum of recurrent thoughts and behaviors that can result from frontotemporal dementia (FTD) and its variants. Although repetitive behaviors can result from a range of brain disorders, FTD is the most common neurologic cause of new-onset recurrent thoughts and behaviors in middle or late life. Patients with FTD can manifest typical or bizarre compulsions, hoarding, verbal and motor stereotypies and complex tics; self-injurious acts, perseverations; and fixed, obsessional thoughts. The frequency and variability of these repetitive behaviors suggest a common disturbance of orbitofrontal-basal ganglia circuits involved in response inhibition. The amelioration of these recurrent events with the administration of serotonin selective reuptake inhibitors further suggests a serotonergic deficit.

TDP-43 proteinopathies: neurodegenerative protein misfolding diseases without amyloidosis

In this review, we summarize recent advances in understanding frontotemporal lobar degeneration (FTLD), amyotrophic lateral sclerosis (ALS) and related neurodegenerative disorders that are collectively known as TDP-43 proteinopathies, since transactive response DNA-binding protein 43 (TDP-43) was recently shown to be the major component of the ubiquitinated inclusions that are their pathological hallmarks. TDP-43 proteinopathies are distinct from most other neurodegenerative disorders because TDP-43 inclusions are not amyloid deposits. Besides TDP-43-positive inclusions, both sporadic and familial forms of FTLD and ALS have the pathologic TDP-43 signature of abnormal hyperphosphorylation, ubiquitination and C-terminal fragments in affected brain and spinal cord, suggesting that they share a common mechanism of pathogenesis. Thus, these findings support the concept that FTLD and ALS represent a clinicopathologic spectrum of one disease, that is, TDP-43 proteinopathy.

TDP-43 proteinopathy: the neuropathology underlying major forms of sporadic and familial frontotemporal lobar degeneration and motor neuron disease

The rapid confirmation of the initial report by Neumann et al. (Science 314:130-133, 2006) that transactive response (TAR)-DNA-binding protein 43 (TDP-43) is the major disease protein linking frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) with and without motor neuron disease (MND) as well as amyotrophic lateral sclerosis (ALS) implies that TDP-43 proteinopathy underlies major forms of sporadic as well as familial FTLD and ALS. Not only was the identity of the ubiquitinated proteins that accumulate in neurons and glia of these disorders finally resolved, but it also was shown that pathologic TDP-43 was hyperphosphorylated, ubiquitinated and cleaved to generate C-terminal fragments in affected brain and spinal cord of FTLD-U and ALS. This review summarizes the growing evidence that TDP-43 proteinopathy is the common pathologic substrate linking FTLD and ALS, and it considers the implications of these findings for developing better strategies to diagnose and treat these neurodegenerative disorders.

Frontotemporal dementias: a review

Dementia is a clinical state characterized by loss of function in multiple cognitive domains. It is a costly disease in terms of both personal suffering and economic loss. Frontotemporal dementia (FTD) is the term now preferred over Picks disease to describe the spectrum of non-Alzheimers dementias characterized by focal atrophy of the frontal and anterior temporal regions of the brain. The prevalence of FTD is considerable, though specific figures vary among different studies. It occurs usually in an age range of 35-75 and it is more common in individuals with a positive family history of dementia. The risk factors associated with this disorder include head injury and family history of FTD. Although there is some controversy regarding the further syndromatic subdivision of the different types of FTD, the three major clinical presentations of FTD include: 1) a frontal or behavioral variant (FvFTD), 2) a temporal, aphasic variant, also called Semantic dementia (SD), and 3) a progressive aphasia (PA). These different variants differ in their clinical presentation, cognitive deficits, and affected brain regions. Patients with FTD should have a neuropsychiatric assessment, neuropsychological testing and neuroimaging studies to confirm and clarify the diagnosis. Treatment for this entity consists of behavioral and pharmacological approaches. Medications such as serotonin reuptake inhibitors, antipsychotics, mood stabilizer and other novel treatments have been used in FTD with different rates of success. Further research should be directed at understanding and developing new diagnostic and therapeutic modalities to improve the patients' prognosis and quality of life.

Pick disease: a brief overview

This article is a brief review of the clinical, radiographic, and pathologic features of Pick disease. It is directed toward residents and fellows in training as well as practicing physicians who might wish to find a concise treatise on this clinicopathologic entity. The pathogenesis and genetics of this disorder are discussed. Included are medical journal articles accessed from computerized medical literature searches of articles published in the last 10 years. Pertinent images have been included where necessary. Although ubiquitously discussed in medical school and residency, Pick disease is nevertheless a relatively uncommon clinicopathologic entity. Recognition of its clinical and pathologic manifestations is critical in correctly diagnosing this illness and subsequently educating family members of the deceased.

A systematic review of neurotransmitter deficits and treatments in frontotemporal dementia

OBJECTIVE

To evaluate neurotransmitter deficiencies and neurotransmitter-based treatments for frontotemporal dementia (FTD).

METHODS

The authors conducted a systematic review of the literature on the mechanism and treatment of FTD and a meta-analysis of treatment studies of antidepressants for the behavioral symptoms of FTD.

RESULTS

Patients with FTD show deficiencies in the serotonin and dopamine neurotransmitter systems, while the acetylcholine system appears relatively intact. Antidepressant treatment significantly improves behavioral symptoms in FTD, but most studies are small and uncontrolled. Serotonergic treatments appear to improve the behavioral but not cognitive symptoms of FTD.

CONCLUSIONS

Studies of neurotransmitter deficiencies in frontotemporal dementia (FTD) can be helpful in developing treatments. Treatment studies on FTD are scarce, given the prevalence and severity of this illness. Larger, well-controlled treatment studies are required to reach more definitive conclusions about treatment efficacy. Multicenter studies are likely the best way to complete treatment studies in a timely manner.

Neuropathologic, biochemical, and molecular characterization of the frontotemporal dementias

The frontotemporal dementias (FTDs) are a heterogeneous group of neurodegenerative disorders that are characterized clinically by dementia, personality changes, language impairment, and occasionally extrapyramidal movement disorders. Historically, the diagnosis and classification of FTDs has been fraught with difficulties, especially with regard to establishing a consensus on the neuropathologic diagnosis. Recently, an international group of scientists participated in a consensus conference to develop such neuropathologic criteria. They recommended a diagnostic classification scheme that incorporated a biochemical analysis of the insoluble tau isoform composition, as well as ubiquitin immunohistochemistry. The use and reliability of this classification system has yet to be examined. In this study, we evaluated 21 cases of FTD. Using traditional histochemical stains and tau protein and ubiquitin immunohistochemistry, we separated each case into one of the following categories: classic Pick disease (PiD; n = 7), corticobasal degeneration (CBD; n = 5), dementia lacking distinctive histopathologic features (DLDH; n = 4), progressive supranuclear palsy (PSP; n = 2), frontotemporal lobar degeneration with motor neuron disease or motor neuron disease-type inclusions (FTLD-MND/MNI; n = 2), and neurofibrillary tangle dementia (NFTD; n = 1). Additionally, we independently categorized each case by the insoluble tau isoform pattern, including 3R (n = 5), 4R (n = 7), 3R/4R (n = 3), and no insoluble tau (n = 6). As suggested by the proposed diagnostic scheme, we found that the insoluble tau isoform patterns correlated strongly with the independently derived histopathologic diagnoses (p < 0.001). The data show that cases containing predominantly 3R tau were classic PiD (100%). Cases with predominantly 4R tau were either CBD (71%) or PSP (29%). Cases with both 3R and 4R tau were either a combination of PiD and Alzheimer disease (67%) or NFTD (33%). Finally, cases with no insoluble tau were either DLDH (67%) or FTLD-MND/MNI (33%). To further characterize these cases, we also performed quantitative Western blots for soluble tau, APOE genotyping, and, in selected cases, tau gene sequencing. We show that soluble tau is reduced in DLDH and FTLD-MND/MNI and that APOE4 is overrepresented in PiD and DLDH. We also identified a new family with the R406W mutation and pathology consistent with NFTD. This study validates the recently proposed diagnostic criteria and forms a framework for further refinement of this classification scheme.

Neurodegenerative diseases: pathology and the advantage of single-cell profiling

The aggregation of neuronal proteins as inclusions is emerging as a common mechanistic theme in neurodegenerative diseases. The presence of these "disease-specific" pathologic changes in the brains of patients with neurodegenerative diseases assist pathologists in the diagnosis and characterization of dementing illnesses. However, these same inclusions may provide valuable clues toward understanding common pathologic roots and shared abnormalities in protein folding across disorders. Such an investigation will likely provide insights into disease mechanisms underlying neurodegenerative disorders characterized by abundant filamentous lesions. This review focuses on two themes: (i) Neurodegenerative disorders are characterized by shared and distinct histopathological and biochemical abnormalities, and (ii) the presence of abnormal protein aggregates may alter a gene, and hence protein expression in inclusion-bearing neurons predisposes them to dysfunction and eventual neuronal degeneration. The pathologic features of neurodegenerative diseases are first discussed followed by a rationale behind sampling mRNA species from single cells rather than from whole-brain homogenates to explore disease mechanisms.

Frontotemporal dementia

In this case study, we describe the symptoms, neuropsychological testing, and brain pathology of a man with frontotemporal dementia (FTD). FTD most often presents with either a change in personality or behavior, such as social withdrawal, increased gregariousness, disinhibition, or obsessive behaviors; or with impairment of language function. Memory difficulties are common, but usually are less prominent than these other symptoms in the early stages of the disease. Frequently, psychiatric diagnoses are initially the primary consideration. Cases may be either familial or sporadic. In this familial case, an autopsy was ultimately performed and revealed findings characteristic of FTD, with grossly evident focal brain degeneration in the frontal and temporal regions, microscopic signs of gliosis, and cellular abnormalities of the intracellular microtubule-associated protein tau.

Drug therapy of frontotemporal dementia

Frontal lobe dementia, or more generally frontotemporal dementia (FTD), includes several clinical entities and, although highly prevalent, lacks any codified therapeutic strategy. The present review is an attempt to depict the main neurochemical correlates of FTD and, as a consequence, to propose the most sound targets for symptomatic drugs. Large scale double-blind controlled clinical trials should be carried out to test any hypothesis: serotonergic agents, glutamate neurotransmission enhancers, monoamine oxidase inhibitors. The recent discovery of tau gene mutations in FTD with Parkinsonism linked to chromosome 17 has reinforced the direct role attributed to abnormal tau proteins (hyperphosphorylation) and thus raised the possibility to target specifically these processes by drugs (aetiopathogenic compounds).