With the global expansion of industrial sectors, noise has emerged as a significant harmful physical agent in workplaces. Besides auditory effects, high-level noise exposure can cause non-auditory consequences, especially at high sound intensities. These effects may include metabolic disturbances such as Metabolic Syndrome (MetS). This study aimed to examine the relationship between noise-induced hearing loss (NIHL) at different sound frequencies and the occurrence of MetS and its defining factors. This cross-sectional descriptive-analytical study was conducted on 1,142 male employees in a petrochemical industry. Fasting blood glucose, triglycerides, and HDL cholesterol were measured from serum samples, and pure-tone audiometry was performed to assess hearing thresholds at 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz. MetS was defined based on the NCEP-ATP III criteria. Data were analyzed using logistic regression models, with MetS as the dependent variable and NIHL as the predictor, adjusting for age, work experience, BMI, and blood pressure. Findings showed the prevalence of MetS and NIHL was 6.92% and 22.24%, respectively. mean hearing threshold across the tested frequencies significantly higher in individuals with MetS than in those without (p 0.05). Among demographic variables, higher BMI and education level were associated with higher odds of MetS. Overall, the results show that frequency-specific patterns of NIHL were associated with a higher likelihood of MetS. Therefore, controlling noise and addressing its non-auditory effects is essential in industrial settings.
Amiri et al. (2026) studied this question.