Facioscapulohumeral muscular dystrophy: a multicenter study on hearing function

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant progressive myopathy, characteristically associated with a 4q35 deletion. In the unusual infantile-onset form of this degenerative disease, sensorineural hearing loss is a frequent clinical manifestation, whereas in patients with typical late-onset FSHD, investigations regarding hearing impairment yielded controversial results. We describe the findings of a multicenter investigation on possible auditory impairment in a series of 73 FSHD patients with a genetically confirmed diagnosis. Among them, 49 cases with no risk factors for deafness, aside from the disease, were identified by a clinical questionnaire and otoscopic examination (mean age 37.8 years, 31 males and 18 females). These subjects were evaluated by pure-tone audiometry. None were aware of hearing loss, while 4 had raised unilateral or bilateral pure-tone audiometric thresholds at 4000 and 8000 Hz, when evaluated by standardized tables. However, the mean raw pure-tone audiometric threshold values for these 49 cases were not significantly different from those of 55 controls (mean age 37.1 years, 32 males and 23 females). Moreover, by statistical analysis, age of onset, degree of muscular weakness and 4q35 EcoRI fragment size made no significant difference to auditory thresholds in our FSHD patients. Overall, the results of our multicenter study suggest that hearing loss in typical FSHD is not more prevalent than in the normal population.