Association between type 1 diabetes mellitus and deposits in the semicircular canals

Objective. To compare the prevalence of cupular and free-floating deposits in the semicircular canals between temporal bones of type 1 diabetes mellitus patients and normal controls. Study Design. Case-control histopathologic human temporal bone study. Setting. Otopathology laboratory in a tertiary academic medical center. Subjects and Methods. Twenty-eight temporal bones from 14 patients with type 1 diabetes mellitus and 56 normal temporal bones from 28 age-matched individuals were histopathologically examined. The cupula and lumina of the semicircular canals were examined for evidence of deposits. Results. The prevalence of cupular and free-floating deposits in the lateral and posterior semicircular canals was significantly higher in type 1 diabetes mellitus patients compared with normal temporal bones (lateral, cupular deposits, odds ratio [OR], 5.47; 95% confidence interval [CI], 1.43 to 21.02; free-floating deposits, OR, 8.25; 95% CI, 2.42 to 27.85; posterior, cupular deposits, OR, 41.73; 95% CI, 5.96 to 275.50; free-floating deposits, OR, 7.44; 95% CI, 1.91 to 28.53). The prevalence of these deposits was associated with the duration of disease rather than with aging. Conclusion. The findings suggest that type 1 diabetes mellitus is associated with cupular and free-floating deposits in the semi-circular canals. The patients with type 1 diabetes mellitus with a longer duration of disease have an increased probability of suffering from benign paroxysmal positional vertigo.