When words first fail: Predicting the emergence of primary progressive aphasia variants from unclassifiable anomic performance in early disease.
Ontology highlight
ABSTRACT: Background
The majority of patients with primary progressive aphasia (PPA) can be distinguished into one of three variants: semantic, non-fluent/agrammatic, or logopenic. However, many do not meet criteria for any one variant.Aim
To identify aspects of cognitive-linguistic performance that yield an early unclassifiable PPA designation that predicted the later emergence of a given variant.Methods & procedures
Of 256 individuals with PPA evaluated, 19 initially were unclassifiable and later met criteria for a variant. Receiver operating characteristic curves were used to evaluate the binary ability of a given task to predict eventual classification as a given variant. Tasks with a high area under the curve were examined using regression analyses to determine their ability to predict variant.Outcomes & results
High mean predictive value was observed for multiple naming assessments targeting nouns and verbs. The Boston Naming Test (BNT) was the only test that, in isolation, resulted in a significant model and high classification accuracy.Conclusions
Although naming impairment is common across PPA variants, very low initial BNT scores emerged as a uniquely accurate basis for predicting eventual semantic variant, and normal BNT scores predicted eventual nonfluent/agrammatic variant. High performance on picture-verb verification was useful in identifying future lvPPA.
SUBMITTER: Stockbridge MD
PROVIDER: S-EPMC10292722 | biostudies-literature | 2023
REPOSITORIES: biostudies-literature
Publications
When words first fail: Predicting the emergence of primary progressive aphasia variants from unclassifiable anomic performance in early disease.
Stockbridge Melissa D MD Tippett Donna C DC Breining Bonnie L BL Hillis Argye E AE
Aphasiology 20220607 8
<h4>Background</h4>The majority of patients with primary progressive aphasia (PPA) can be distinguished into one of three variants: semantic, non-fluent/agrammatic, or logopenic. However, many do not meet criteria for any one variant.<h4>Aim</h4>To identify aspects of cognitive-linguistic performance that yield an early unclassifiable PPA designation that predicted the later emergence of a given variant.<h4>Methods & procedures</h4>Of 256 individuals with PPA evaluated, 19 initially were unclass ...[more]
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