Clinical Progression in Four Cases of Primary Progressive Apraxia of Speech

Purpose: This case series details the clinical progression of patients with primary progressive apraxia of speech (PPAOS) to illustrate, using several methods and supplemental material examples, the changes that occur in speech and language functioning in this patient population. Method: Four patients who presented with PPAOS were followed between 5 and 6 years. Two patients had predominant articulatory abnormalities (termed phonetic PPAOS), 1 had predominant prosodic abnormalities (prosodic PPAOS), and 1 had relatively equal articulatory and prosodic abnormalities (mixed PPAOS). Detailed speech (including acoustics), language, neurologic, and neuropsychological data were collected. Results: At initial exam, the patients ranged from 60 to 77 years old, with presenting disease duration of 1.5-10 years. Although all patients presented with an isolated apraxia of speech, all developed varying degrees of aphasia and dysarthria. Patients with phonetic PPAOS developed relatively more severe aphasia than the other 2 patients. All patients eventually had severe functional communication limitations and required alternative or augmentative means of communication, although at varying times postonset of their initial speech problem. Two patients developed dysphagia, 3 showed mild-moderate Parkinsonism, and 2 developed depression. For all patients, simple temporal acoustic measurements documented slowed speech rate over time. Conclusions: This case series demonstrates that patients who initially present with PPAOS may develop aphasia and dysarthria, cognitive and behavioral changes, and other neurologic signs. Whether these changes can be predicted by the perceptual characteristics of the apraxia of speech is yet to be determined. The detailed longitudinal profiles provide valuable clinical insight into the progression of disease in people with PPAOS.