Clinical Study to Evaluate the Association Between Sensorineural Hearing Loss and Diabetes Mellitus in Poorly Controlled Patients Whose HbA1c >8

Abstract

The relationship between sensorineural hearing loss (SNHL) and Diabetes mellitus has been known since more than 150 years. The pathophysiology of diabetes related hearing loss is speculative. Hearing loss is usually, bilateral, gradual onset, affecting higher frequencies. This study aims at knowing the prevalence of SNHL in DM and its relation to age, sex, duration of DM and control of DM. A total of 50 type 2 diabetics of age group 30-65 years were involved in the study. FBS, PPBS, HbA1c of all the subjects were done and later subjected to PTA. The type and severity of hearing loss was noted. Occurrence of SNHL was later compared with age, sex, duration, and control of DM. Sensorineural hearing loss was found in 66 % of type II diabetic patients and 34 % were found normal. Out of 50 diabetes mellitus patients, 33 patients had SNHL. All cases of SNHL detected were of gradual in onset and no one had hearing loss of sudden onset. Normal hearing was found in 34 % of patients, whereas 54 % of patients had mild hearing loss and 12 % of patients had moderate hearing loss. Association of hearing loss of DM patients with sex of the patient is insignificant. However there is significant association between older age group, longer duration and uncontrolled DM with that of SNHL. In subjects with HbA1c more than 8 and duration of diabetes mellitus more than 10 years prevalence of SNHL is more than 85 %, which is statistically significant. Sensorineural hearing loss in diabetes mellitus is gradually progressive involving high frequency thresholds. Hearing threshold increases with increasing age duration of diabetes and also high level of HbA1c greater than 8 %.

Keywords: Diabetes mellitus; HbA1c; Pure tone audiometry; Sensorineural hearing loss; Tuning fork tests.