Balbuzie evolutiva e indici predittivi di cronicità: il 'Profilo delle Disfluenze'

Stuttering is a speech disorder that occurs, without known origin, in around 10% of population. The onset is around 33 month (mean age) and the 90% of affected people recovers spontaneously, most of the time within 4 years from the onset. When it persists after puberty it becomes a chronic adult speech disorder throughout the lifespan (Yairi & Ambrose, 2005). Due to difficulties in eradicating stuttering in adulthood, it would be very useful to identify, among pre-school stuttering children, the future persistent stutterers, in order to begin the treatment as early as possible. This would enhance the treatment effectiveness and prolong its benefits (Starkweather, 1993), reserving the therapeutic efforts only to children at-risk of persistence. The purpose of this study is to follow the development of the disorder in 4 pre-school Italian children, audio-recorded from the onset of stuttering to the following 18 months, in order to identify early prognostic indexes of persistence as close as possible to the onset. One of the indexes, proposed by Yairi & Ambrose (2005), aims at tracing the developmental disfluencies profile. According to it, stuttering children who will spontaneously recover reduce the proportion of the "stuttering-like disfluencies" (repetitions of sounds and syllablese, repetitions of monosyllabic words, silent and audible prolongations) over the total number of disfluencies in the first year after the onset. The data show that the predictive power of this index is low in the first year after the onset, but increases in the next six months. Since no reliable clinical tool exists yet for predicting persistent stuttering, it is suggested that this probabilistic index should be studied on a larger sample of stuttering children in order to test its predictive value.