P-574 Saliva Cortisone in Noise-Exposed Workers

Introduction Human saliva and blood cortisol are biomarkers of noise-induced stress. In the salivary glands, the free fraction of blood cortisol is converted into the saliva cortisone, which is more concentrated in saliva than the cortisol. Data on the saliva cortisone concentration in noise-exposed workers are scarce. Methods The study included 104 (57.7% male and 42.3% female) 19-30 years old participants split in two groups. A group of 50 workers was regularly exposed to occupational noise (loud music and machines) 1-2 years before the enrolment in the study. The level of intensity was at least 85 dB(A), and exposure to ototoxic solvents was excluded. Another group of 54 medical students was not exposed to occupational noise. Saliva was collected by a synthetic fiber roll that was kept in the mouth and then centrifuged. In extracted saliva, the cortisone and the cortisol were determined by high-performance liquid chromatography. All of the participants were not currently using oral or intranasal corticosteroids. Results Saliva cortisone concentration was significantly higher in noise-exposed workers (32.4, IQR 18.5-49.8 nmol/L) compared to students (21.2, IQR 18.0-23.6 nmol/L), P<0.001. Saliva cortisol concentration was significantly higher in noise-exposed workers (6.9, IQR 8.7-11.2 nmol/L) compared to students (6.8, IQR 6.1-7.1 nmol/L), P<0.001. Discussion Noise-exposed workers had high saliva concentrations of both cortisone and cortisol. Conclusion Further investigations should consider other causes of the increased saliva cortisone concentration, and explore correlation between saliva cortisone and audiological findings of noise-induced hearing loss. Conclusion Saliva cortisone could be considered as a biomarker of noise-induced stress.