Sudden hearing impairment combined with diabetes mellitus or hyperlipidemia.

The objective of this study was to delineate whether the presence of the risk factors of microvascular disorder (MD) contribute to the prognostic outcome in patients with idiopathic sudden deafness (ISD). Retrospective clinical record review was conducted with 106 patients of ISD. Pure tone hearing thresholds were compared among the groups with or without hyperglycemia and hypercholesterolemia. Significantly better hearing recoveries were observed in cases with hyperglycemia as compared with controls. There was a tendency that the magnitude of hearing recovery in hypercholesterolemia was greater than that of controls although there was no statistical difference. The presence of the risks in MD could be an indicator of better hearing prognosis of ISD if we choose appropriate treatments. Heterogeneity of the ISD makes the establishment of the relationship between the risk factors of MD and etiology of some cases of ISD. We may have to choose the treatments for ISD considering whether the patient has any risk factor of MD.