Hearing loss in Norwegian adults with achondroplasia.

BACKGROUND

Achondroplasia is the most common form of disproportionate skeletal dysplasia. The condition is caused by a mutation in the FGFR3 gene, affecting endochondral bone growth, including the craniofacial anatomy. Recurrent otitis media infections, chronic middle ear effusion, and hearing loss are common in children with achondroplasia, but few studies have investigated hearing loss in adults with this condition.

OBJECTIVES

This population-based study investigated the prevalence, severity, and type of hearing loss in Norwegian adults with achondroplasia.

METHODS

We collected data on 45 adults with genetically confirmed achondroplasia: 23 men and 22 women, aged 16-70 years. All participants underwent a comprehensive audiologic assessment, including medical history, pure-tone audiometry, speech audiometry, and impedance audiometry. According to the Global Burden of Disease classification, pure-tone average ≥ 20 decibel hearing level (dB HL) was considered clinically significant hearing loss.

RESULTS

Insertion of ventilation tubes had been performed in 44% (20/45) of the participants, 49% (22/45) had a history of adenoidectomy, while 20% (9/45) used hearing aids. Hearing loss in at least one ear was found in 53% (24/45) of the participants; in 57% (13/23) of the men and 50% (11/22) of the women. In the youngest age group (age 16-44 years), 50% (14/28) had hearing loss, although predominantly mild (20-34 dB HL). An abnormal tympanometry (Type B or C) was found in 71% (32/45) of the participants. The majority (15/24) had conductive hearing loss, or a combination of conductive and sensorineural hearing loss (8/24).

CONCLUSIONS

Adults with achondroplasia are at increased risk of early hearing loss. Our findings underline the importance of a regular hearing assessment being part of standard care in achondroplasia, including adolescents and young adults. In adult patients diagnosed with hearing loss, an evaluation by an otolaryngologist should be considered, and the need for hearing aids, assistive listening devices, and workplace and educational accommodations should be discussed. Clinical trial registration ClinicalTrials.gov identifier NCT03780153.