Task performance to discriminate among variants of primary progressive aphasia

Melissa D Stockbridge; Donna C Tippett; Bonnie L Breining; Emilia Vitti; Argye E Hillis

doi:10.1016/j.cortex.2021.09.015

Task performance to discriminate among variants of primary progressive aphasia

Cortex. 2021 Dec:145:201-211. doi: 10.1016/j.cortex.2021.09.015. Epub 2021 Oct 14.

Authors

Melissa D Stockbridge¹, Donna C Tippett², Bonnie L Breining³, Emilia Vitti³, Argye E Hillis⁴

Affiliations

¹ Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address: md.stockbridge@jhmi.edu.
² Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
³ Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
⁴ Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Cognitive Science, Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD, USA.

Abstract

Primary progressive aphasia can be distinguished into one of three variants: semantic, non-fluent/agrammatic, and logopenic. While a considerable body of work exists characterizing each variant, few prior studies have addressed the problem of optimizing behavioral assessment in a typical outpatient evaluation setting. Our aim is to examine the sensitivity and specificity of a battery of cognitive and linguistic assessments and determine optimal scores for distinguishing patients' subtype based on these instruments. This was a retrospective analysis of outpatient clinical testing of individuals with known or suspected primary progressive aphasia. Evaluations included the National Alzheimer's Coordinating Center frontotemporal lobar degeneration module and additional measures of naming, semantic association, word verification, and picture description. Receiver operating characteristic analysis was used to examine the utility of each task in distinguishing each variant from the others. Logistic regressions were used to examine the combined utility of tasks for distinguishing a given subtype. We examined 435 evaluations of 222 patients retrospectively. The battery was most consistent in distinguishing semantic variant by low scores and non-fluent/agrammatic variant by high scores on a similar subset of tasks. Tasks best distinguishing semantic variant produced a model that correctly classified 86% of cases. Tasks best distinguishing non-fluent/agrammatic variant correctly classified 77% of cases. The battery of tasks was weakest in identifying logopenic variant; only the ratio of sentence reading to sentence repetition performance was identified as a reasonable predictor, and it had predictive accuracy of 67%. Naming assessments were the strongest basis for distinguishing all variants, particularly semantic variant from non-fluent/agrammatic variant. These data illustrate that a number of commonly used assessments perform at chance in distinguishing variant and preliminarily support an abbreviated battery that marginally favors tools not currently included in the frontotemporal lobar degeneration module.

Keywords: Aphasia; Dementia; Evaluation; Language.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Aphasia, Primary Progressive* / diagnosis
Humans
Language Tests
Neuropsychological Tests
Retrospective Studies
Task Performance and Analysis*

Abstract

Publication types

MeSH terms

Grants and funding