Long-Term Outcomes for Individuals With Childhood Apraxia of Speech.

Purpose: The study's primary aims were to describe the long-term speech outcomes for adolescents and young adults with a history of childhood apraxia of speech (CAS) and to examine the association of persistent speech sound errors with measures of literacy skills, phonological processing, motor speech production, and parent report of early motor difficulty.

Method: Data from a large longitudinal 25-year study were used to explore outcomes for 32 individuals with a history of CAS, ages 12;6 (years;months) to 25 years (M = 17.4, SD = 4.7). Persistent and nonpersistent groups were compared on decoding, phonological processing, multisyllabic word repetition, diadochokinetic rate, and parent report of motor involvement. Parametric (Welch's t tests) and nonparametric tests (Wilcoxon and Fisher exact tests) were used to identify differences between the groups' distributions. Developmental trajectories of speech production were plotted.

Results: Outcomes for individuals with CAS are highly variable, with some demonstrating speech sound errors into adolescence and young adulthood. Speech sound errors were primarily on later developing sounds. Persistence was significantly associated with early motor difficulties. Difficulties with multisyllabic words, phonological processing, and literacy were often present regardless of persistence or nonpersistence of speech errors.

Conclusions: Children with CAS are at risk for persistent speech sound errors into adulthood. For children showing limited progress with more traditional speech therapy, alternative interventions should be explored. Individuals with persistent speech sound errors are more likely to have a history of early motor deficits. Regardless of persistence, participants with CAS demonstrated ongoing weaknesses in literacy, phonological processing skills, and complex speech production tasks.