179225 Vitamin A and Age-related Hearing Loss among Older Japanese

Sunday, October 26, 2008

Takehiro Michikawa, MD , Department of Preventive Medicine and Public Health, Keio University, Tokyo, Japan
Nishiwaki Yuji , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Kikuchi Yuriko , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Hosoda Kanae , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Ishigami Ai , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Iwasawa Satoko , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Nakano Makiko , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
Mizutari Kunio , Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Keio University, Tokyo, Japan
Saito Hideyuki , Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Keio University, Tokyo, Japan
Takebayashi Toru , Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan
PURPOSE. As oxidative stress has been suggested to be involved in auditory ageing, the preventive role of antioxidants is expected. However, epidemiological evidence on this topic is lacking. We carried out a community-based cross-sectional study to clarify the association between serum antioxidants and age-related hearing loss among older Japanese.

METHODS. Study subjects were 758 residents (329 males and 429 females) aged 65 years old or older, which was 53% of the eligible population in this area. By using pure-tone audiometric test (30, 50dB at 1kHZ and 40dB at 4kHz), the subjects were defined as having hearing impairment when they failed to hear the 30dB at 1kHz and 40dB at 4kHz in their better ear. Serum antioxidants (alpha-, gamma-tocopherols, beta-cryptoxanthin, alpha-, beta-carotenes, lycopene, lutein plus zeaxanthin, and retinol) were measured by HPLC. The relation between antioxidant levels and hearing impairment was examined in crude and multivariate analyses.

RESULTS. The prevalence of hearing impairment was 21.9% in males and 18.0% in females. Among antioxidants, retinol, beta-cryptoxanthin and alpha-, beta-carotenes (the latter three was defined as provitamin A) were associated with hearing impairment. After adjusting for age, sex, smoking, alcohol drinking, total cholesterol and hypertension, odds ratios of hearing impairment for the highest quartile compared to the lowest were 0.45 (95% CI; 0.24 to 0.84) for retinol and 0.49 (0.28 to 0.87) for provitamin A family.

CONCLUSIONS. These findings suggest that vitamin A may protect against age-related hearing loss. A follow-up study is needed.

Learning Objectives:
1. A population-based cross-sectional study among older Japanese 2. Discuss the preventive role of antioxidants as for age-related hearing loss. 3. Evaluate the association between serum antioxidants and age-related hearing loss.

Keywords: Aging, Epidemiology

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: no conflict of interest
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

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