RISK FACTORS FOR HEARING IMPAIRMENT IN TYPE 1 DIABETES

Objective:

Studies have demonstrated that HbA1c is a significant predictor of hearing impairment in type 1 diabetes. We identified additional factors associated with hearing impairment in participants with type 1 diabetes from the Diabetes Control and Complications Trial and its observational follow-up, Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study.

Methods:

1,150 DCCT/EDIC participants were recruited for the Hearing Study. A medical history, physical measurements, and a self-administered hearing questionnaire were obtained. Audiometry was performed by study-certified personnel and assessed centrally. Logistic regression models assessed the association of risk factors and comorbidities with speech- and high-frequency hearing impairment.

Results:

Mean age was 55±7 years, duration of diabetes 34±5 years, and DCCT/EDIC HbA1c 7.9±0.9%. In multivariable models, higher odds of speech-frequency impairment were significantly associated with older age, higher HbA1c, history of noise exposure, male sex, and higher triglycerides. Higher odds of high-frequency impairment were associated with older age, male sex, history of noise exposure, higher skin intrinsic florescence (SIF) as a marker of tissue glycation, higher HbA1c, non-professional/non-technical occupations, sedentary activity, and lower LDL cholesterol. Among participants who previously completed computed tomography and carotid ultrasonography, coronary artery calcification (CAC)>0 and carotid intima-medial thickness were significantly associated with high- but not speech-frequency impairment.

Conclusion:

Consistent with previous reports, male sex, age, several metabolic factors, and noise exposure are independently associated with hearing impairment. The association with SIF further emphasizes the importance of glycemia, as a modifiable risk factor, over time. In addition, the macrovascular contribution of CAC is novel and important.