Biomarkers in the primary progressive aphasias

Murray Grossman
2014 Aphasiology  
Background-Primary progressive aphasia (PPA) is a progressive disorder of language that is increasingly recognised as an important presentation of a specific spectrum of neurodegenerative conditions. Aims-In an era of etiologically specific treatments for neurodegenerative conditions, it is crucial to establish the histopathologic basis for PPA. In this review, I discuss biomarkers for identifying the pathology underlying PPA. Main Contribution-Clinical syndromes suggest a probabilistic
more » ... ion between a specific PPA variant and an underlying pathology, but there are also many exceptions. A considerable body of work with biomarkers is now emerging as an important addition to clinical diagnosis. I review genetic, neuroimaging and biofluid studies that can help determine the pathologic basis for PPA. Conclusions-Together with careful clinical examination, there is great promise that supplemental biomarker assessments will lead to accurate diagnosis of the pathology associated with PPA during life and serve as the basis for clinical trials in this spectrum of disease. Keywords Frontotemporal degeneration; Primary progressive aphasia; Biomarker Primary progressive aphasia (PPA) is an insidious worsening of language associated with a spectrum of disease processes described under the umbrella term of fronto-temporal lobar degeneration (FTLD), or with Alzheimer's disease (AD). There are no community-based surveys documenting the frequency of PPA in the population. Nevertheless, this condition is not uncommon. One rough estimate of the frequency of PPA, derived from autopsy-based studies, estimates that about 40% of cases FTLD pathology have PPA (Forman et a!.This suggests a prevalence for PPA in the range of 1.1-6 per 100,000 and an incidence of about 0.88-1.4 per 100,000 with FTLD pathology, and additional cases with Alzheimer pathology. The average age of onset tends to be in the late 50s , although a wide range of onset age is reported, and we know little about the factors
doi:10.1080/02687038.2014.929631 pmid:25580048 pmcid:PMC4287262 fatcat:rpv2ns23gvfchhdwys2vwxk2ji