Language Skills in Patients With Alexander Disease

Purpose: This study aimed to investigate the language skills of children with Alexander disease (AxD) and determine whether disease subtypes and/or age contributes to variability in language performance. Method: Eighty-two participants with AxD, confirmed by GFAP testing, were enrolled, and the disease phenotype was determined using clinical and imaging features (56 cerebral, nine intermediate, and 17 bulbospinal). The participants' language abilities were assessed using the Preschool Language Scale–Fifth Edition (PLS-5), the Clinical Evaluation of Language Fundamentals–Fifth Edition (CELF-5), and the Peabody Picture Vocabulary Test–Fourth Edition (PPVT-4), based on the patient's age and linguistic level. The Communication Function Classification System was also used to determine functional communication abilities. Wilcoxon signed-ranks test or Kruskal–Wallis test was used to determine differences across groups. Results: The mean PLS-5 Total Language Score (TLS) was 70.10 ( SD = 17.62). Performance on the CELF-5 varied by phenotype (Core Language Score [CLS]: cerebral, M = 57.22, SD = 19.89; intermediate, M = 92.50, SD = 20.54; bulbospinal, M = 91.56, SD = 19.51). PLS-5 performance was negatively correlated with age at the first research study visit for cerebral participants (TLS: rho = −.367, p = .017). CELF-5 and PPVT-4 scores, on the other hand, were not correlated with age at first visit but with age at first neurological symptom (CLS: rho = .576, p = .003; PPVT-4: rho = .336, p = .011). Conclusions: Cerebral patients demonstrated significant language deficits, whereas intermediate and bulbospinal subjects displayed stronger abilities, with deficits in some patients. These implications can be used to determine the functional impact of communication deficits and to provide accommodations and interventions in the treatment plans of patients with AxD.