# Correlation of Indoxyl Sulfate to Hearing Impairment in Chronic Kidney Disease Patients

## TL;DR

This study finds a strong link between high levels of indoxyl sulfate in CKD patients and hearing loss, suggesting the toxin contributes to auditory impairment.

## Contribution

The study demonstrates a novel correlation between indoxyl sulfate levels and hearing function in stage 5 CKD patients.

## Key findings

- Indoxyl sulfate levels strongly correlate with the degree of auditory impairment (r = 0.881; p = 0.001).
- There is an inverse relationship between indoxyl sulfate levels and SNR (r = -0.761; p = 0.001).
- CKD patients show hearing impairment linked to accumulated uremic toxins like indoxyl sulfate.

## Abstract

Chronic Kidney Disease (CKD) is considered a public health issue because its frequency is increasing in adults. When a person experiences renal failure, one of the most researched solutes that builds up in plasma is indoxyl sulfate. This toxin can attach to proteins, and it is a byproduct of the tryptophan metabolism in the diet, which provides pro-oxidative and pro-inflammatory activity. In CKD, the redox imbalance associated with oxidative stress is associated with pathophysiological issues brought on by the buildup of uremic toxins. The cochlea is highly susceptible to oxidative stress, which consequently causes permanent cochlear degeneration. To better understand the connection between Indoxyl sulfate levels and hearing loss in CKD patients, we examined the results of pure tone audiometry and OAE examinations.

This research was conducted on 27 people with stage 5 CKD who had their blood plasma levels of indoxyl sulfate measured before having their hearing ability assessed by OAE and pure tone audiometry. Next, a correlation test was carried out between the results of Indoxyl sulfate levels and the results of hearing function tests in CKD patients.

The indoxyl sulfate value and degree of auditory impairment had a strong positive correlation, according to the Spearman correlation test. (r = 0.881; p = 0.001) and an inverse relationship between the Indoxyl sulfate value and SNR (r = -0.761; p = 0.001).

CKD patients have impaired hearing, which is correlated with the amount of uremic toxin Indoxyl Sulfate that has accumulated.