Vitamin E, antioxidants may prevent hearing loss
of unknown origin, Israeli researchers will report this weekend.
The results, which found the vitamin to improve recovery of the disease, suggest that antioxidants may play a role in the prevention and restoration of hearing loss.
Each year some 4,000 Americans report the onset of sudden hearing loss but little is known about the cause of the disease. About two thirds of patients with ISHL recover without treatment within days but for those who do not, there is no consistently supported treatment.
But there is some preliminary evidence to suggest that antioxidants may help treat the disease. Previous research has shown that superoxide anion radicals (O2-) appear in the inner ear of experimental animals after damage caused by noise-induced trauma, administration of ototoxic drugs (those that damage the ears), and inflammatory disease.
Other studies have shown that antioxidants could prevent the ototoxicity of cisplatin, a common chemotherapy drug.
To find out whether antioxidants may have a restorative or protective role in the inner ear, researchers from the Technion-Israel Institute of Technology in Haifa, Israel, randomly divided 66 patients, with an average age of 41, with sudden hearing loss into two groups.
The basic treatment of both groups was identical (including bed rest and steroids) except for the addition of 800 mg of vitamin E per day taken by the study group. The severity of hearing loss was only marginally significant in the rate of recovery but the success of treatment, defined as improvement of 75 per cent or more at the time of discharge, was significantly better in the study group.
The recovery rate of more than 75 per cent was achieved in 26 (more than three quarters) patients in the vitamin E group compared with 15 (45 per cent) patients in the control group.
The antioxidant properties of vitamin E have been known for many years. Since its discovery, vitamin E has been recognized as an essential factor in neurologic function. It has also been associated with prevention of cardiovascular diseases, reduction of risk of cancer, and functioning of the immune system.
"Further studies should be directed toward a better understanding of the role of antioxidants in idiopathic sudden hearing loss," said the researchers.
Their findings are being presented at the American Academy of Otolaryngology-Head and Neck Surgery Foundation Annual Meeting & OTO EXPO in New York this weekend. The research is also discussed in the July 2003 issue of Otology & Neurotology (24(4):572-5).
