Association Between Hemoglobin A1c andAll-CauseMortality:Results of the Mortality Follow-up of the German National Health Interview and Examination Survey

The study population comprised 6,299 participants (aged 18–79 years) of the German National Health Interview and Examination Survey 1998, who were followed up for mortality for an average of 11.6 years. Glycemic status was defined as known diabetes (self-reported diagnosis or intake of antidiabetic medication) and based on HbA1c levels according to American Diabetes Association diagnostic criteria as undiagnosed diabetes (‡6.5% [‡48 mmol/mol]), prediabetes with very high (6.0–6.4% [42–46mmol/mol]) or highdiabetes risk (5.7–5.9% [39–41mmol/mol]), and normoglycemia (<5.7% [<39 mmol/mol]). Associations between glycemic status and mortality were examined by Cox regression adjusting for age, sex, education, lifestyle factors, anthropometric measures, and history of chronic diseases (reference: normoglycemia). Spline models were fitted to investigate associations between continuous HbA1c and mortality among participants without known diabetes.