Conductive Hearing Loss in Patients with Active Acromegaly

Abstract

There have been rare conflicting results reported concerning possible higher frequency of hearing loss in acromegalic patients. Our goal was to determine whether there is higher frequency of conductive hearing loss in acromegalics and what may cause it if there is any. Prospective study. Tertiary referral center. Thirty previously untreated patients with acromegaly were compared with 20 age- and sex-matched healthy control subjects. In all subjects: Otomicroscopy, tuning fork tests, audiometry tympanometry, cochleostapedial reflex, otoacoustic emissions. In acromegalics: endocrinologic assessment, MRI and if necessary, epipharyngoscopy. We searched for: 1) Signs of ossicle fixation: absence of stapedial reflex in the presence of normal tympanogram, conductive hearing loss, and absence of or grossly disturbed OAE; 2) Disturbances of middle ear ventilation: excessive negative pressure (tympanogram type C), or middle ear effusion (tympanogram type B). The only statistically significant difference between untreated acromegalics and healthy subjects was the presence of middle ear ventilation problem: 7/30 acromegalics (23%) in comparison to none out of 20 healthy controls (0%), p = 0.033. The acromegalics with middle ear ventilation problem were significantly older, had longer duration of the disease, and lower mean growth hormone (GH) levels in comparison with acromegalics without this problem (51.6 +/- 1.7 vs. 44.4 +/- 2.5 years, 11.6 +/- 2.4 vs. 7.7 +/- 0.4 years, 21.68 +/- 4.89 vs. 49.98 +/- 12.54 microg/L respectively). Patients with active acromegaly have more frequent middle ear ventilation problem than normal population, especially those with longer duration of the disease. Possible causes are discussed.