Objective: This study presents a potentially novel method of screening for pathogenetic factors in diabetic audiopathy by comparing the absolute plasma concentration of a microangiopathy biomarker, stromal cell-derived factor 1a (SDF-1a), with frequency-specific audiometric results.
Background: Impaired hearing function in diabetic patients has, to date, remained a controversial and poorly understood theme with sparse clinical data. This is in contrast to more established components of the disease such as diabetic retinopathy, where diabetic microangiopathy is thought to be of pathogenetic relevance, and specific molecules such as SDF-1a have been assigned a relevant role.
Clinical setting: Out patient clinic, Vienna General Hospital, Medical University of Vienna.
Patients: 18 Type 2 diabetic patients and 18 nondiabetic controls.
Materials and methods: Pure-tone audiometry and Freyburger number tests were used to evaluate hearing function. Blood plasma values of SDF-1a were analyzed using an enzyme-linked immunosorbent assay. Statistical comparison of functional audiometric data and the absolute SDF-1a values was performed for all frequencies.
Results: A significantly higher plasma SDF-1a concentration (p < 0.005) in Type 2 diabetic patients, who also presented with higher pure-tone audiometry thresholds compared with nondiabetic subjects, was noted. Furthermore, an association between SDF-1a and audiometric performance, body mass index, and duration of diabetes was observed.
Conclusion: We hypothesize that diabetic microangiopathy and its biomarker SDF-1a should be considered as potential pathogenetic factors for altered diabetic hearing, warranting further investigation.