The relationship between noise-induced hearing loss and cognitive function.

Abstract

Introduction: NIHL may affect some domains of cognitive function. This study was conducted to assess the relationship between NIHL and working memory, attention and response time.

Materials and methods: This was a cross-sectional study on 154 textile workers with exposure to noise higher than 85dBA in a textile factory. The participants were divided into two groups: with and without NIHL and some domains of cognitive function were compared between two groups. Wechsler working memory test and Stroop color-word test were used to measure working memory, selective attention and response time. Data were analyzed by SPSS (ver. 24) using student's T test, and multiple linear regression model.

Results: Totally, 154 workers entered the study (77 with NIHL and 77 without NIHL). All participants were males. Working memory score and response time were higher and interference score was lower in NIHL group, although only the difference in working memory was significant. Due to the significant difference of age and work history between case and control groups, cognitive parameters were compared between two groups after adjusting for these two variables, but the significance was not changed.

Conclusion: This study showed that noised-exposed middle-aged males with NIHL had probably a lower working memory span than their counterparts without NIHL.