The clinical study of audiologic manifestations of type 2 diabetes mellitus in association with other diabetic microvascular complications: an observational study

Abstract

Background: Sensorineural hearing loss (SNHL) is a major clinical and public health problem. Diabetes mellitus (DM) is characterized by various microvascular and macrovascular complications. DM is associated with thickening of basal membrane of the stria vascularis capillaries on the lateral wall of cochlea and neuropathic changes which leads to SNHL.Methods: This is an observational study involving 160 participants grouped into diabetics and non-diabetics. DM was diagnosed using standard American Diabetes Association (ADA) criteria. All the participants were subjected to pure tone audiometry to detect SNHL which was graded into mild, moderate, severe and profound based on degree of decibel loss. The occurrence of SNHL was compared with the occurrence of microvascular complications among diabetics.Results: In our study, 34 (42.5%) cases and 8 (10%) of controls had SNHL. The occurrence of SNHL was higher among diabetics than non-diabetics (p <0.0001) with majority (88.23%) of cases having bilateral SNHL. Among diabetics, 26 (32.5%) had neuropathy, 23 (28.75%) had retinopathy, 21 (26.25%) had nephropathy. There was no statistically significant relationship between occurrence of SNHL and microvascular complications among diabetics (p=0.8614). The occurrence of SNHL correlated with the levels of HbA1c (p = 0.017). The occurrence of SNHL among diabetics was 42.5% as compared to only 10% among non-diabetics which was statistically significant. The occurrence of SNHL correlated with the levels of HbA1c among diabetics suggesting an association between DM and SNHL (p=0.017).Conclusions: There was increased occurrence of sensorineural hearing loss among the individuals with diabetes mellitus with significant relationship with the glycaemic index.