Hypercholesterolemia is Suggested to be an Independent Risk Factor of Incident Hearing Loss in Japanese Men and Women Undergoing Health Screening

抄録

Background and Aims: Hypercholesterolemia has been suggested to be a risk factor of hearing loss. However, most of the epidemiological studies showing this were cross-sectional and controversial. The aim of this longitudinal study was to find independent risk factors of incident hearing loss.

Methods: This was an 8-year follow-up study to find risk factors of high-frequency hearing loss (HFHL) and low-frequency hearing loss (LFHL) in 2,628 and 2,775 participants, respectively. The threshold levels of HFHL and LFHL were defined at the 40 dB (4,000 Hz) and the 30 dB (1,000 Hz) for a better ear, respectively. Age and sex adjusted hazard ratios (HRs) of incident hearing loss were calculated for candidate risk factors. Then, stepwise Cox regressions were performed. Similar calculations were made excluding subjects older than 60 years.

Results: HFHL and LFHL developed in 18.4% of men and 6.5% of women and 8.7% of men and 9.5% of women, respectively. The incidence of hearing loss was markedly higher in participants older than 60 years: 53.4% in men and 20.6% in women and 28.4% in men and 26.9% in women, respectively, for HFHL and LFHL. Smoking and daily alcohol drinking were independent risk factors of HFHL while hypercholesterolemia was an independent risk factor of LFHL for all participants. Hypercholesterolemia and smoking were independent risk factors of HFHL while hypercholesterolemia and anemia were independent risk factors of LFHL after excluding subjects older than 60 years.

Conclusions: Our results suggested that hypercholesterolemia was an independent risk factor of both HFHL and LFHL after excluding subjects older than 60 years. Individuals with hypercholesterolemia should be recommended to undergo audiometry and avoid risk factors of hearing loss.