Effect of hyperbaric oxygen therapy on thiol/disulfide homeostasis in patients with idiopathic sudden sensorineural hearing loss

Introduction: Idiopathic sudden sensorineural hearing loss (ISSNHL) is an otologic emergency that can lead to loss of function in one of the most important human senses. Recently, hyperbaric oxygen therapy (HBOT) has gained popularity with pharmacotherapy in ISSNHL. This study aimed to determine changes induced in thiol/disulfide homeostasis (TDH, a new biomarker of systemic oxidative stress) by pharmacotherapy and HBOT in patients with ISSNHL.Methods: This prospective study analyzed the albumin, total thiol, native thiol, and disulfide levels and disulfide-native thiol, disulfide-total thiol, and native thiol-total thiol ratios before and after HBOT with standardizing pharmacotherapy using a new colorimetric method in patients with ISSNHL.Results: 41 patients with ISSNHL including 14 (34.1%) women and 27 (65.9%) men participated in the study. The mean age of the patients was 48.02 ± 13.10 years. Of them, 24 (58.5%) had hearing loss in the right ear and 17 (41.5%) had hearing loss in the left ear. There was a statistically significant decrease in the albumin (p<0.001), total thiol (p<0.001), native thiol (p<0.001), and disulfide (p<0.001) levels after treatment compared to baseline. There was no statistically significant difference in the disulfide-native thiol (p=0.148), disulfide-total thiol (p=0.172), and native thiol-total thiol (p=0.169) ratios after treatment compared to baseline. Conclusion: Consequently, this study demonstrated that the thiol-disulphide balance tended to shift towards the oxidative side after HBOT and pharmacotherapy compared to baseline in patients with ISSNHL and that patients with high oxidation level after treatment had better treatment response