Profiles of Language Impairment in Progressive Nonfluent Aphasia

Abstract

Objective: To study language in noncaucasian patients with progressive nonfluent aphasia (PNA). To determine differences in the language impairment in PNA patients with and without early onset behavioral changes. Materials and Methods: Based on clinical evaluation, six PNA patients were divided into those with ( EB , n =2) and without ( NB , n =4) early onset (i.e., within 24 months from onset) behavioural symptoms of frontotemporal dementia (FTD). NB was sub-grouped as Moderate (language plus subtle cognitive dysfunction; n =2) and Mild (isolated language dysfunction; n =2). Language on the western aphasia battery (WAB) of NB was compared with that of EB and of the three groups were compared with that of controls. Clinical follow-up ranged between 24 and 60 months from onset. Results: Three categories were matched for the disease duration. Compared to controls, significantly (P <0.05) lower scores were seen for all three groups on WAB fluency, repetition and writing; for the Moderate and EB on reading, naming and comprehension; and for the EB alone on information content. Information content and comprehension were significantly lower for the EB when compared to the NB. Over comparable periods, the aphasia quotient of patients in EB declined by more than 30 points and in the Moderate by 3 points. Conclusions: PNA frequently shows behavioral features suggestive of FTD early in the course of the illness. Poor information content on WAB differentiates patients with early behavioral dysfunction from those without. The extent of language impairment is a function of the disease stage rather than of disease duration, suggesting thereby that the "initial 2 years of relatively isolated language disorder" criteria, while useful, may exclude some patients with PNA.