Prevalence of hearing impairment in retinitis pigmentosa population

Abstract

Objectives: Sensorineural hearing loss (SNHL) is the most common disease associated with systemic retinitis pigmentosa (RP). Usher syndrome (USH) is a major autosomal recessive disorder characterized by bilateral SNHL and visual impairment caused by RP. USH constituted 43% of systemic RP. Prevalence of USH varies and ranges from 3.5 to 6.2 per 100,000. We conducted a nationwide survey of hearing impairment associated with RP to estimate the prevalence of hearing loss, onset of hearing impairment and proportions of the progressive hearing impairment and vestibular disturbance. Methods: The epidemiological data were derived from questionnaire study on those subjects who were membership registers of the Japanese Retinitis Pigmentosa Society (n = 3200). The questionnaire comprised 10 questions for investigating hearing impairment-related problems such as onset of hearing impairment, awareness of tinnitus or vestibular disturbance or progressive hearing impairment, and history of audiological examination and hearing aid. Results: A total of 834 questionnaires were returned (26.1% response rate) and were analyzed by 828 (25.9%) subjects, who were diagnosed by an ophthalmologist as RP. The prevalence of hearing impairment or tinnitus was 29.5% (n = 244) and 30.4% (n = 252), respectively. The prevalence of cochlear symptom was 42.8% (n = 346). Mean age of hearing impairment onset was 39.2 years. 72.5% of the 244 subjects with hearing impairment had history of audiological examination. The hearing-aid users were 57 subjects (23.4%). Progressive hearing impairment, tinnitus, or vestibular disturbance was experienced in 46.2%, 43.4%, and 58.1%, respectively. Conclusion: The prevalence of hearing impairment in PR population was high and the clinical features were various.