Diabetes mellitus, glycosylated heamoglobin levels and hearing impairment in adults

Background: The aim of this study is to examine the auditory function in adult diabetics and to determine the association between, duration of diabetes, glycosylation, and hearing impairment. Methods: A one year hospital based prospective study of adult diabetic patients consecutively attending the endocrinology clinic of university of Maiduguri teaching hospital. Fasting blood sugar and glycosylated heamoglobin levels were estimated. The degree of hearing loss was assessed using pure tone average of air conduction thresholds at frequencies between 250-8000 Hz. Equal number of healthy controls matched for age and sex had PTA. Results: There were 150 patients recruited but 127 patients (50 males and 77 females; mean age: 47.8 ±11.6) years were analyzed. The 1-5 years duration of diabetes was the highest constituting 43.4% of patients (43.4%). The mean fasting blood sugar and glycosylated heamoglobin levels were 8.6 mmol/L ± 4.1 and 9.0% ± 2.0%, respectively. Mild sensorineural hearing loss was observed in 63 (49.6%) patients. There was no significant correlation between the diabetics PTA and the controls (p=0.542). The duration of illness significantly correlated with hearing impairment (p<=0.0001), but there was no significant correlation between glycosylated heamoglobin levels and hearing impairment, (p=0.154). Conclusion: Mild sensorineural hearing loss (SNHL) is the main type of hearing impairment in diabetics. Duration of illness correlated significantly with hearing impairment