Citations

Purpose The primary aim was to examine the utility of the Western Aphasia Battery–Revised (WAB-R; Kertesz, 2007 ) for classifying variants of primary progressive aphasia (PPA). Traditional WAB-R metrics of Aphasia Quotient (AQ), subtest scores, WAB-R classification, and several novel metrics were examined. A secondary aim was to examine these same WAB-R metrics in individuals with primary progressive apraxia of speech (PPAOS). Method A retrospective analysis of WAB-R records from 169 participants enrolled in a study of neurodegenerative speech and language disorders was conducted. PPA/PPAOS classification was determined by consensus review of speech, language, and cognitive profiles. Scores on each of the WAB-R subtests were obtained to derive AQ, WAB-R aphasia profile, and 3 ratios reflecting relative performance on subtests. Results Mean AQ was significantly higher in the PPAOS group compared to all PPA variants except primary fluent aphasia. AQ above the normal cutoff was observed for 20% of participants with PPA. Significant main effects of group were noted for each of the subtests. Follow-up comparisons most frequently discriminated PPAOS, primary agrammatic aphasia (PAA), and logopenic progressive aphasia. Primary fluent aphasia and semantic dementia (SD) subtest scores were less distinctive, with the exception of Naming for SD, which was significantly lower than for PAA and PPAOS. When the WAB-R AQ detected aphasia, a classification of anomic aphasia was most frequently observed; this pattern held true for each of the PPA variants. The mean Information Content:Naming ratio was highest for SD, and the mean Comprehension:Fluency ratio was highest for PAA. Conclusions In the current study, AQ underestimated the presence of PPA and WAB-R classification did not distinguish among PPA classification determined by consensus. Performance on individual subtests and relative performance across subtests demonstrated inconsistent alignment with PPA classification. We conclude the WAB-R in isolation is inadequate to detect or characterize PPA. We instead suggest utilizing the WAB-R as 1 component of a comprehensive language and motor speech assessment when PPA is suspected.

The specific effect of TDP-43 pathology on grey matter volume in individuals without frontotemporal lobar degeneration is unclear. Bejanin et al. reveal a major and independent contribution of TDP-43 to neurodegeneration and shed light on the regional distribution of TDP-43-related atrophy in older adults.

ABSTRACTObjectivesWhen the 2017 Movement Disorders Society Criteria for progressive supranuclear palsy is applied, patients may appear to have multiple phenotypes. The maximum allocation extinction rules were developed to provide a consistent method for applying the criteria and reaching a single diagnostic label. In this study, we apply both to a neuropathologic cohort of progressive supranuclear palsy and other parkinsonian conditions.MethodsAn autopsy cohort of 54 patients with progressive supranuclear palsy and 56 patients with other neuropathologic diseases was selected. Clinical data were retrospectively abstracted, and the diagnostic criteria for progressive supranuclear palsy were applied. All possible phenotypes applicable were listed and maximum allocation extinction rules were applied to assess reduction in the number of phenotypes ascribed per patient.ResultsIn the progressive supranuclear palsy group, 52 patients met the criteria for multiple phenotypes, with an average of 7 phenotypes per patient. In the nonprogressive supranuclear palsy group, all 56 patients had features of more than one phenotype, up to 3 per patient. After application of maximum allocation extinction rules, the majority of the patients in both groups had a single predominant phenotype. Freezing of gait, supranuclear gaze palsy, and frontal behavioral syndrome were more common in the progressive supranuclear palsy group.ConclusionsThe diagnostic criteria for progressive supranuclear palsy identify many clinical features, thereby leading to assignment of multiple phenotypes per patient. We demonstrate that the maximum allocation extinction rules can effectively lead to a single consensus phenotype, maintaining a uniform diagnostic label for clinical and research applications.

ABSTRACTBackgroundThe Movement Disorder Society clinical criteria for progressive supranuclear palsy (PSP) provide a framework for assessing the presence/severity of clinical symptoms and define a speech/language variant of PSP.ObjectivesTo evaluate the clinical criteria in a cohort of speech/language patients with longitudinal follow‐up.MethodsA total of 52 patients presenting with progressive apraxia of speech and/or agrammatic aphasia were followed longitudinally for up to 6 visits with clinical assessments and magnetic resonance imaging. We assessed oculomotor, postural instability, and akinesia diagnostic levels and determined whether patients met criteria for possible PSP‐speech/language or probable PSP at each visit. Kaplan‐Meier curves assessed time‐to‐event probabilities according to age. Statistical parametric mapping and midbrain volume were assessed according to disease progression.ResultsFew PSP symptoms were observed early in the disease, with oculomotor abnormalities and falls first observed 2 years after onset. Falls were more common than vertical supranuclear gaze palsy. Bradykinesia and rigidity commonly developed but axial was rarely greater than appendicular rigidity. During follow‐up, 54% met criteria for possible PSP‐speech/language, 38% for probable PSP‐Richardson's syndrome, and 38% for probable PSP‐parkinsonism, most commonly 6 to 6.9 years after onset. The probability of developing PSP was greater when onset was at an age older than 70 years. Patients who progressed to probable PSP had more parkinsonism and oculomotor impairment at baseline and greater midbrain atrophy when compared with those who did not develop probable PSP.ConclusionsSymptoms typical of PSP commonly develop in patients presenting with a progressive speech/language disorder. Older age appears to be an important prognostic factor in these patients.

Abstract Agrammatic aphasia affects grammatical language production and can result from a neurodegenerative disease. Although it typically presents with concomitant apraxia of speech, this is not always the case. Little is known about the clinical course and imaging features of patients that present with agrammatism in the absence of apraxia of speech, which we will refer to as progressive agrammatic aphasia. We aimed to make a detailed description of the longitudinal clinical, linguistic, and neuroimaging features of a cohort of 11 patients with progressive agrammatic aphasia to provide a complete picture of this syndrome. All patients underwent detailed speech and language, neurological and neuropsychological assessments, 3 T structural and diffusion tensor imaging MRI, 18F-fluorodeoxyglucose and Pittsburgh compound B PET. The 11 patients were matched by age and gender to 22 patients who had mixed apraxia of speech and agrammatism. The progressive agrammatic aphasia patients performed abnormally on tests of language, general cognition, executive function, and functional ability at baseline and declined in these measures over time. Only two patients eventually developed apraxia of speech, while parkinsonism was absent-to-mild throughout all visits for all patients. When compared to the patients with mixed apraxia of speech and agrammatism, the patients with progressive agrammatic aphasia performed better on tests of motor speech and parkinsonism but more poorly, and declined faster over time, on tests of general aphasia severity, agrammatism, and naming. The patients with progressive agrammatic aphasia also showed different neuroimaging abnormalities, with greater atrophy, hypometabolism and white matter tract degeneration in the prefrontal and anterior temporal lobes compared to patients with mixed apraxia of speech and agrammatism. These differences were more pronounced as the disease progressed. These results demonstrate that progressive agrammatic aphasia has a different clinical disease course and different underlying neuroanatomical abnormalities than patients with the more common syndrome of mixed agrammatism and apraxia of speech. This supports the distinction of progressive agrammatic aphasia and has implications for the classification of patients with agrammatic aphasia.