Hearing loss in children with type 1 diabetes

To examine the auditory function in a group of children with type 1 diabetes, and to study the association between hearing impairment and duration of illness, metabolic control and diabetic complication.

Sixty-three diabetic patients below the age of 18 attending the university hospital in Khartoum, Sudan were investigated together with 63 age and sex matched non-diabetic controls. Pure-tone audiometric tests were performed using an Amplaid 300 clinical audiometer in a soundproof room. Both air and bone conduction were tested at frequencies between 250-8000 Hz and 250-4000 Hz respectively. Hearing impairment was noted at auditory threshold above 25 dB in any frequency and the magnitude of hearing loss was assessed according to auditory threshold in conversational frequencies only.

The hearing acuity was lower in the diabetic patients than in the control subjects in all tested frequencies, but the differences achieve statistical significance only at middle and high frequencies. The hearing loss was symmetrical, generally mild, and affects both sexes equally. Duration of diabetes, HbA1c concentration, and angiopathic complications showed positive correlation with the increased hearing thresholds; while, age at onset, insulin dose per day, presence of neuropathy, and frequency of DKA and hypoglycaemic episodes were not associated.

Hearing loss occurs early in diabetic children and is related to the duration of the disease and the degree of metabolic control. Strict glycemic control might prevent or delay this complication.