1. Introduction

Diabetes is more prevalent among women over 50 years of age, retired people, urban dwellers and people with low income. Diabetes affects patients in different ways. It can cause other disorders and is associated with a high mortality rate. It reduces quality of life and is a heavy financial burden. The cost of treating patients with diabetes is three times higher than the general population. Diabetes can also affect the auditory and vestibular systems. Many diabetic patients experience dizziness, imbalance, oscillopsia and gait disturbances due to impaired vestibular function. In some diabetic patients, auditory and vestibular tests show abnormal results. The relationship between diabetes and dizziness or imbalance has been evaluated in some studies. Many diabetic patients are elderly and the aging process can greatly affect this relationship. Many elderly patients have auditory and vestibular dysfunction, and many cases of bilateral vestibular dysfunction occur in the elderly. Moreover, imbalance and falls are more common in elderly and also in elderly with diabetes Various tests such as pure tone audiometry (PTA), video head impulse test (v-HIT), ocular vestibular evoked myogenic potential (o-VEMP) and cervical vestibular evoked myogenic potential (c-VEMP) are useful to assess auditory and vestibular function. The present study was aimed to evaluate the auditory and vestibular function of diabetic patients and compare the results with those of a healthy control group.

This study evaluated auditory and vestibular function in patients with type 2 diabetes mellitus. The results showed mild auditory and vestibular dysfunction in some patients compared to a healthy control group. Hearing loss was mainly observed at high frequencies. Overall, some aspects of the relationship between diabetes and hearing loss are still controversial. Some studies like this one have shown cases of hearing loss in diabetic patients, especially at higher frequencies in patients younger than 50 years of age. On the other hand, some studies showed no association between diabetes and the risk of hearing loss. The difference between different studies may be due to many different factors. Some researchers have found an association between the duration of diabetes and the degree of hearing loss. This may be due to differences and contradictions between studies. Moreover, the severity of diabetes and how it is controlled may affect this relationship. The number of patients with hearing loss was higher in patients with poorly controlled diabetes than in patients in the well-controlled groups. The quality of diabetes control was also unknown across studies and may have influenced the study results. The degree and incidence of hearing loss also varied between studies; however, some studies showed similar results to the present study. Various mechanisms have been proposed for the association between diabetes and hearing loss, which include oxidative stress, microvascular abnormalities atrophy or thickening of the vascular striatum auditory neuropathy auditory neuropathy auditory cell dysfunction. due to altered electrolyte homeostasis in the endolymph of auditory cell damage and damage to outer hair cells. Histopathological findings in diabetic patients also include sclerosis of the internal auditory artery and thickening of the basilar membrane and vascular band. Changes in auditory brainstem responses were also observed in insulin-dependent diabetic patients. These results also indicated an association between diabetes and vestibular dysfunction. It has been reported that diabetes may increase the risk of vestibular dysfunction. Even patients with bilateral vestibular hypofunction have a higher risk of developing diabetes. In the current study, v-HIT test results were abnormal in some patients and there was a significant difference between the two groups. However, the results of c-VEMP and o-VEMP were normal in most cases. Increased latency or abnormal amplitude asymmetry was observed in only a few cases. In several studies, vestibular function was assessed using different tests. Vestibular hyperreflexia was the main outcome of the study using the caloric test. These results are similar to the v-HIT results obtained in the present study. Although both of these tests evaluate the semicircular canals, the vEMP results are slightly different. In another study, more abnormal results were observed with the c-VEMP test in diabetic patients compared to the o-VEMP test. Abnormal c-VEMP results were also found in type 1 diabetic patients with or without polyneuropathy. Overall, abnormal and inconsistent c-VEMP results were observed in some studies, so more research in this area is needed to explain these discrepancies. The c-VEMP and o-VEMP tests evaluate the otolith system. Otolith dysfunction can cause vertigo, imbalance, and lead to benign paroxysmal positional vertigo (BPPV). The prevalence of DPPD is higher in diabetic patients. Otolith dysfunction also increases the risk of recurrence of DPPH. Various mechanisms contributing to vestibular dysfunction include degeneration of vestibular nerve myelin damage to hair sac cells changes in metabolism in the inner ear microvascular changes and connective tissue changes. The advantage of the present study is the inclusion of adult participants to exclude the effects of aging. The effects of diabetes and the aging process on the auditory system may be similarThe combination of diabetes and the aging process may have a greater impact on auditory and vestibular function. Vestibular dysfunction is also more common in older patients and diabetic patients. A limitation of this study concerns the effect of diabetes on an individual's balance.

In general, the risk of imbalance and falls is increased in patients with diabetes. However, imbalance in these patients may be associated with dysfunction of various systems and is not limited to vestibular dysfunction. Imbalance in diabetic patients may be associated with retinopathy vestibular dysfunction as well as decreased somatosensitivity and tactile sensation. Diabetes mellitus (DM) is one of the most prevalent endocrinological diseases worldwide. Studies investigating neurological disorders in endocrine diseases have shown that in type 1 DM, disorders in the nervous system progress despite the adequacy of replacement therapy. At the present stage of society development little attention is paid to the prevention of complications of the initial stages of development of nervous system disorders, in particular, those characteristic of dysfunction of the auditory and vestibular analyser. At the same time, a course of therapeutic and preventive measures at the early stages of development is the most effective. In addition, an overall increase in the number of patients with diabetes mellitus has been recorded over the past 20 years. Epidemiological studies conducted in different countries also indicate an increase in the incidence of patients with type 1 diabetes in recent decades.

The onset of the disease in childhood, the variability of the course of the disease can lead to early disability and the threat of death due to not only acute but also chronic complications of type 1 diabetes mellitus. This provides for the development of the most optimal methods of early diagnosis, prevention and rehabilitation of type 1 diabetes mellitus. To date, there have been no studies of cochleovestibular disorders in patients with diabetic neuropathy. Preventive examinations to identify individuals with balance or hearing impairment are carried out only in highly specialised institutions, predominantly in persons over 40-50 years of age, and are unable to reflect the state of the problem as a whole. In addition, this almost completely excludes the possibility of identifying persons with minor balance or hearing impairments and, consequently, of providing them with timely rehabilitation measures, which in some cases prevent the progression of the process and their further disability.

In the aspect of solving this problem, a promising direction is the study of the relationship between statokinetic and hearing disorders. is the study of the relationship between the statokinetic and auditory systems and compensation of type 1 DM. It can be reasonably assumed that the influence of blood glucose level and related disorders in the organism is reflected in the functions of the auditory and vestibular analysers. The use of data on the study of changes in this area will allow to substantiate new approaches to the diagnosis, prevention and correction of cerebral disorders, and will contribute to the optimisation of the currently existing principles of rehabilitation of DM patients and improve their quality of life in the future.

2. Conclusions

Thus, the relevance of the study of pathophysiological changes in the auditory and vestibular analysers in type I diabetes mellitus from the standpoint of early diagnosis of auditory and statokinetic function disorders, determined the aims and objectives of the present study.