Hearing and balance functions in adults with ıron deficiency.

Background: Because the inner ear requires high-energy metabolism and because of the iron content of some cochlear enzymes, iron deficiency-related hypoxia can affect hearing and the balance system.

Objectives: To evaluate the hearing and balance functions in adults with iron deficiency (ID) and iron deficiency anemia (IDA).

Material and methods: 22 ID patients, 22 IDA patients and 22 healthy controls underwent pure tone audiometry (0.125-16 kHz), VNG, VEMP, and vHIT.

Results: Significant differences were observed in the hearing thresholds of the IDA group at frequencies ranging from 0.125 kHz to 14 kHz, as well as in the ID group at frequencies of 2.0 kHz, 4.0 kHz, and 6.0 kHz. The pursuit test was pathological at the rate of 40.9% in the IDA group. The oVEMP test showed prolonged latency values in both ID and IDA groups. IDA group had lower p1-n1 amplitude than the control group in the oVEMP and cVEMP tests. A significant difference was determined between the groups concerning anterior SCC VOR gains.

Conclusions and significance: The hypoxia caused by anemia might negatively impact hearing and vestibular functions. The current study is the first study to comprehensively evaluate anemia patients with VNG, VEMP, and vHIT tests.