Objectives: Diabetes mellitus is a common comorbid condition of hemochromatosis and is often identified as a complication of untreated hemochromatosis. However, there are few primary data examining the development of diabetes secondary to hemochromatosis. Our objective was to determine the likelihood of developing diabetes in a nationally representative cohort of patients who have an elevated serum transferrin saturation rate but no current diagnosis of diabetes.
Study design: This is a retrospective cohort study based on merging the National Health and Nutrition Examination Survey I (1971-1974; NHANES I) with the NHANES I Epidemiologic Followup Study (1992).
Population: Individuals aged 25 to 74 years at the time of the NHANES I without diabetes (n = 9274).
Outcomes measured: The outcome was development of diabetes according to patient report, proxy report, or death certificate by the time of the follow-up interview.
Results: The incidence of diagnosed diabetes in the cohort was 10.2%. Among individuals with serum transferrin saturation levels above 55%, 7.5% developed diagnosed diabetes compared with 10.2% with a serum transferrin saturation of no more than 45% (P =.38). The relation remained nonsignificant in models adjusted for risk factors of diabetes and in analyses that assumed 10% of patients had received treatment for hemochromatosis.
Conclusions: In this nationally representative cohort of adults, elevated serum transferrin saturation was not significantly associated with the development of diabetes.