Inner ear involvement in rheumatoid arthritis: a prospective clinical study

Sensorineural hearing loss in rheumatoid arthritis (RA) has been reported to be the result of the extra-articular manifestation of the disease (rheumatoid nodular vasculitis) or due to drug ototoxicity. In an attempt to investigate the presence of sensorineural hearing loss and the possible causes for it we investigated prospectively 45 RA patients (42 female; three male) with a mean age of 52.5 +/- 10.7 years and a mean disease duration of 8.5 +/- 7.3 years. All patients underwent a complete physical examination and audiological evaluation which included pure tone audiometry and impedance audiometry (tympanogram, static compliance, acoustic reflex, reflex decay, acoustic reflex latency test. We found a sensorineural hearing loss > 20 dB HL in 44.4 per cent (40/90) ears. In all cases the site of hearing loss was the cochlea and in most of them it was bilateral and symmetric (16 patients out of 45 had bilateral sensorineural hearing loss i.e. 35.5 per cent. There was no correlation between sensorineural hearing loss and age, sex, disease duration, articular and extra-articular manifestations and the presence of autoantibodies in our patients. In addition, no correlation was found between sensorineural hearing loss and drug therapy for one at least of the following drugs: NSAIDs, D-penicillamine, plaquenil and methotrexate. We noticed a prologation of acoustic reflex latency in five patients (10 per cent) which was found to be correlated with the temporomandibular joint involvement and the presence of rheumatoid factor (RF). We conclude that inner ear involvement in RA is expressed by: (1) mild symmetric, bilateral sensorineural hearing loss of cochlear type in 35.5 per cent of patients; (2) normal acoustic reflex thresholds; (3) nondecay; and (4) prologation of acoustic reflex latency which appeared in a small number of patients (10 per cent).