Interleukin-6 gene polymorphism and hearing loss related to the history of occupational noise exposure in Brazilian elderly

摘要

Noise-induced hearing loss (NIHL) is an interaction of both genetic and environmental factors. Some studies have led to the identification of possible NIHL susceptibility genes. The aim of the present study was to investigate whether the polymorphism of the interleukin (IL)-6 gene at position -174 was associated with complaints of hearing loss due to occupational exposure. Cross-sectional study in a population sample with 141 individuals aged over 60 years with and 50 without history of occupational noise exposure in Brazil, through anamnesis and audiological evaluation and IL-6 genotyping by the PCR-RFLP technique. The variables studied were frequency of hearing loss and polymorphism (SNPs). Chi-square test was used in order to control likely confusion or modification the effect of other variables on interest associations. Hearing loss was reported in 73.8% of elderly with history of occupational noise exposure. 37.2% and 56.0% of the elderly were heterozygous and homozygous for allele G, respectively. No significant associations between the genotypes of these SNP and NIHL were obtained in the Brazilian population. The NIHL was statistically associated with sex and age (x~2=11.24; p＜0.05; x~2=7.34; p=0.007; respectively). No association was found with the polymorphism of the IL-6 gene and hearing loss associated with the occupational noise exposure history in Brazilian elderly.