Thyroid-stimulating hormone and free thyroxine alterations in subjects with occupational hearing loss

[helvella]

This is a very unusual article as so little seems to have been published relating hearing and thyroid.

Not sure that this paper actually gets us very far. In my view, it is not at all surprising to see relationships between hearing and thyroid. But exactly how would occupational hearing loss affect thyroid?

Year : 2021 | Volume : 25 | Issue : 1 | Page : 4-10

Thyroid-stimulating hormone and free thyroxine alterations in subjects with occupational hearing loss

Nastaran Ranjbar1, Hossein Namvar Arefi2, Mohammad Maarefvand2, Akram Pourbakht2, Ali Shahbazi3

1 Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran

2 Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran

3 Cellular and Molecular Research Center, Iran University of Medical Sciences; Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran

Abstract

Context and Aim:

Occupational hearing loss (OHL) is caused by exposure to industrial noise. Alterations in the thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels are related to hearing loss. The purpose of this study is to investigate the TSH and FT4 level alterations in OHL.

Methods and Material:

Among 428 subjects, 144 male workers with normal hearing (NH), noise-induced hearing loss (NIHL), and high tone loss (HTL) (N = 48 in each group) were included in this study. All the subjects had normal TSH and FT4 levels.

Results:

The TSH level is higher in the HTL and NIHL groups in comparison to NH, but it is only significant in the HTL group. The FT4 level is significantly lower in the NIHL group; however, the lower FT4 level in the HTL group is not significant when compared to the NH group.

Discussion:

The NIHL group may turn into the HTL group over time. This process could be monitored by alteration in their TSH and FT4 levels.

Conclusions:

Alterations in the TSH and FT4 levels could be considered as a pathophysiology for OHL. More research is required to investigate the electrophysiological, physiological, and histological correlations of TSH and FT4 and different types of hearing loss caused by noise exposure.

Keywords: Hearing loss, noise exposure, thyroid-stimulating hormone, total thyroxine

Full paper freely available here:

ijoem.com/article.asp?issn=...

[Mollyfan]

This is really interesting. I found another study looking at the relationship between Thyroid function and sudden sensorineural hearing loss. I am interested as I have Hashimoto’s with poor conversion and my daughter suffered profound SSRI at 29. They checked her TSH but not T3 as far as I know.

sciencedirect.com/science/a...

[jimh111]

Will not have time to read the study. Hypothyroidism causes reversible hearing loss when the fine hairs in the ear that pick up sound are lost. I was unable to pick out conversations in a crowd until my hypothyroidism was corrected. It may be that a high noise environment helps dislodge hairs in people who are hypo. The study would be much better if it was an intevention trial where the subjects were give thyroid hormone for a few weeks before being re-tested.

[TSH110 in reply to jimh111]

Yes my hearing improved dramatically after treatment, even on Levothyroxine monotherapy. Traffic noise used to drive me nuts before I was diagnosed and my hearing was terrible.

[tattybogle]

Excellent thankyou . My fT4 is over range > Mr next door is very busy with his hammer drill >This study shows that noise induced hearing loss and lower fT4 go hand in hand > problem solved .. i was going to ask him to shut up but i'll let him carry on now.,

[Mollyfan in reply to tattybogle]

Haha!I think you need to carry out a controlled experiment and tell him to stop so you can test your hearing. Not double blind but hey ho!

[helvella Administrator Thyroid UK in reply to Mollyfan]

Not double blind...

More double deaf?

[Batty1]

Hearing issues and thyroid definitely go together. Im deaf in one ear and only have 40% left in the other ear and prior to my thyroidectomy I couldn’t hear a simple conversation or hear a smoke alarm go off even though I never recovered my hearing in my dead ear the other ear is better then ever I can hear pretty much everything now.