Longitudinal characterization of patients with progressive apraxia of speech without clearly predominant phonetic or prosodic speech features

Abstract

Most recent studies of progressive apraxia of speech (PAOS) have focused on patients with phonetic or prosodic predominant PAOS to understand the implications of the presenting clinical phenotype. Patients without a clearly predominating speech quality, or mixed AOS, have been excluded. Given the implications for disease progression, it is important to understand these patients early in the disease course to inform appropriate education and prognostication. The aim of this study was to describe a cohort of ten patients with initially mixed PAOS and how their clinical course evolves. Four patients were rated prosodic predominant later on (mild AOS at first visit); five were later designated phonetic (four with more than mild AOS at first visit); one was judged mixed at all visits. The study suggests patients without a clear predominance of speech featuresshould still be included in PAOS studies and thought of on the continuum of the disease spectrum.

Keywords: Aphasia; Apraxia of speech; Degenerative; Dysarthria; Neurologic disorders.

Figure 1.

Writing samples for the two patients who developed a clear change in handwriting patterns between their first (left) and last (right) samples (patient 4 top; patient 2 bottom). First and last writing samples for the remaining patients can be found in Appendix 1.

Figure 2.

Super and left medial views of FDG-PET scans for each patient, at the first and last visit at which scans were available. Patient ID is noted in the row header; visit number (and years since first visit) is noted prior to each scan.