Abstract:
Diabetes mellitus (DM) is a universal health problem. According to the International Diabetes Federation (IDF), 425 million people world-wide are affected by DM. With such high incidence of DM, health professionals aim to avoid possible secondary disorders which impact health related quality of life (HRQoL) (Kamali, Hajiabolhassan, Fatahi, Esfahani, et al., 2013)(a). These secondary disorders include disorders of the inner ear.
The aim of the current study was to describe auditory-vestibular function in adults with type 1 DM and to determine the impact of the disease on their risk of falls and HRQoL. Data from this group was compared to data obtained from a control group of non-diabetic age and gender matched adults. A total of 30 type 1 DM participants and 30 non-diabetic participants were included in the study. Participants underwent a series of tests. Auditory tests: otoscopy, acoustic immittance measurements and air conduction (AC) pure tone audiometry were done. Vestibular tests included cervical- and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs) and video head impulse test (vHIT). Fall risk assessments included dynamic gait index (DGI), berg balance scale (BBS) and timed up and go test (TUG). Participants also completed the EQ-5D-5L Health Questionnaire.
A significant difference was observed between the diabetic and non-diabetic groups’ 4-tone pure tone average (PTA) and thresholds for frequencies 250Hz-4000Hz in the left ear and at 250Hz-8000Hz in the right ear. No significant differences were present in cVEMPs between the two groups. The diabetic group was more likely to have absent oVEMPs on the right. For the right ear a significant difference was present between the diabetic and non-diabetic participants median oVEMP N1 latency but was still within normal limits for both groups. For both ears a significant difference was present in oVEMP amplitude. A significant difference was present between the diabetic and non-diabetic groups’ vHIT anterior gain and posterior gain for the left and right ear respectively. The fall risk assessment scores in the current study indicated a low fall risk and good mobility in both groups. Diabetic participants rated their HRQoL to be significantly poorer than the non-diabetic participants. Type 1 DM individuals had a significantly higher occurrence of auditory dysfunction, a higher occurrence of vestibular dysfunction but not for risk of falling compared to the non-diabetic participants. Furthermore, diabetic participants were found to have a significantly poorer HRQoL. Hearing and vestibular function tests as well as psychosocial support need to be considered as an integral part of type 1 DM patient’s management strategy. The auditory- and vestibular function of individuals with type 1 DM should be closely monitored to better prevent further damage that places them at a higher risk of falls and serious life threatening injuries which will decrease patients HRQoL.