A prospective study of hyperlipidemia as a pathogenic factor in sudden hearing loss.

The pathogenic role of hyperlipidemia in sudden hearing loss (SHL) was examined in a prospective study. Twenty-five patients (14 males, 11 females; age range, 23-59 years) with a first event of SHL (group I) were compared with 9 patients (4 males, 5 females; age range, 28-86 years) with a repeated event of SHL (group II). Audiological examination revealed different types of SHL in group I vs group II: high-frequency loss, 76% vs 22%; low-frequency loss, 12% vs 22%; pancochlear hearing loss, 12% vs 56%. Serum lipid patterns and atherogenic risk factors in both groups were not different and corresponded to lipid patterns in the average population. These findings indicate that both hyperlipidemia and atherogenic risk factors are not of major pathological importance in SHL.