Investigation of auditory thresholds in type 2 diabetic patients compared to non-diabetic cases

Background: Hearing loss is one of the common complaints of diabetics. The aim of this study was to evaluate the hearing status of diabetic patients in Babol, North of Iran. Methods: The hearing status of 50 type 2 diabetic patients (case group) and 50 healthy individuals (control group) were evaluated from October 2011 to September 2012. Audiometry was done with the frequencies of 250, 500, 1000, 2000, 4000, 6000, 8000 HZ and speech tests like SRT (speech reception threshold), SDS (speech discrimination score) were performed. The data were collected and analyzed. Results: The mean age of case group was 50.1±3 and in control group was 49.9±3.2 years. Hearing thresholds were 10.55.6, 10.76.1, 15.27.1, 169.6, 21.213.5, 26.416.5, 28.32 db in the right ear of the case group and 11.25.3, 9.74.9, 127.1, 14.29.4, 20.913.3, 25.115.6, 27.620.2 db in control group with different frequencies (p<0.05). Similar results were obtained in the left ear of both groups. The mean SRT in the right ear of the case group was 15.77.7 and control group was 9.24.8 and 13.56.9 in case and 9.14 in the left ear of case group (P=0.0001). SDS was 94.33.7 and in 96.23.3 in the right ear for the case and control group, respectively (P=0.0001). For the left ear, these values were 94.44.4 and 95.93.2, respectively (P=0.023). Conclusion: The results show that hearing loss in different frequencies and speech reception threshold were higher in diabetic group but speech discrimination score was higher in normal individuals. Audiological monitoring is recommended in diabetic patients during therapy.