The effect of aging on the vestibular system

Aim: To examine the effects of aging on vestibular system functions. Material and Method: Healthy individuals aged 18 years and older who met the inclusion criteria were included in the study. As a result of the power analysis, the sample size of the study was determined as 28 for each age groups, namely, 18-40 years (Group 1), 41-60 years (Group 2), and 61 years and over (Group 3). VNG, vHIT, c-VEMP, o-VEMP, and the Berg Balance Scale were administered in all individuals included in the study. Results: There was a statistically significant difference between age groups in terms of Berg Balance Scale scores (p<0.05). VNG test results were normal in Groups 1 and 2. Saccade test and optokinetic test were found pathological in 8 of the individuals in Group 3. There was no difference between age groups in terms of accuracy parameter in the saccade test (p>0.05). In terms of other parameters of the saccade test and evaluation parameters of the smooth pursuit and optokinetic tests, Group 3 differed significantly from Groups 1 and 2 (p<0.05). There was no difference between age groups in terms of mean gain asymmetry of the lateral channels in vHIT (p>0.05). There was a significant difference between age groups in terms of other evaluation parameters of vHIT (p<0.05). In the lateral canal evaluation, saccades were not observed in Group 1, while 1 overt and 1 covert-overt saccades were observed in Group 2. In Group 3, covert saccades were observed in 2 individuals, overt in 11 individuals, and covert-overt saccades in 1 individual. In c-VEMP, there was no difference between age groups in terms of P1-N1 interlatency and asymmetry rate (p>0.05). There was a significant difference between groups in terms of the other parameters of the c-VEMP and evaluation parameters of o-VEMP (p<0.05). Conclusion: It is important to consider the changes observed in test parameters with increasing age in clinical evaluations. In addition, the findings of the study may guide the application of rehabilitative approaches specific to the affected vestibular functions. Keywords: Balance, Vestibular Function, Vestibular System, Aging