Signs of dysarthria in adults with 22q11.2 deletion syndrome.

The aim of the study was to investigate how adults with 22q11.2 deletion syndrome (22q11DS) performed on dysarthria and intelligibility tests compared with a control group. Ten participants with confirmed 22q11.2 deletion, five males and five females with a mean age of 31 years (range: 19-49), were compared with a control group matched for gender and age (five males and five females, mean age: 32 years, range: 19-49). Assessment of non-verbal and verbal tasks reflecting respiration, phonation, oral motor function, velopharyngeal function, articulation, and prosody was performed as well as the Swedish Test of Intelligibility (STI). All assessments were made by two raters; inter-rater and intra-rater reliability was acceptable. The participants with 22q11DS had significantly more problems than the control group on all investigated dimensions except the STI. Overall, the severity of their speech deviation was rated as mild to moderate. The largest difficulties were found regarding speech respiration, phonation, oral motor function, and velopharyngeal function. The results of the present study suggest that a neurological etiology could be added to the previously described structural etiology explaining the speech difficulties found in 22q11DS. Signs of difficulties in both speech motor planning and speech motor programming were found. Further studies are needed to confirm the results, as are studies of the association between structural brain abnormalities and neurological speech symptoms. For clinical purposes, it is important that clinicians have knowledge about the variable speech symptoms that may occur in individuals with 22q11DS and that they be aware of the complexity of the etiology of such speech symptoms.