Fasting glucose is the standard measure used to diagnose diabetes in the United States. Recently, glycated hemoglobin was also recommended for this purpose.

The glycated hemoglobin value at baseline was associated with newly diagnosed diabetes and cardiovascular outcomes.

For glycated hemoglobin, values of less than 5.0%, 5.0-5.5%, 5.5-6.0%, 6.0-6.5%, and 6.5% or greater, the hazard ratios for diagnosed diabetes were 0.52, 1.00, 1.86, 4.48, and 16.47, respectively.

For coronary heart disease, the hazard ratios were 0.96, 1.00, 1.23, 1.78, and 1.95, respectively. The hazard ratios for stroke were similar.

In contrast, glycated hemoglobin and death from any cause were found to have a J-shaped association curve.

The association between the fasting glucose levels and the risk of cardiovascular disease or death from any cause was not significant.

In this community-based population of nondiabetic adults, glycated hemoglobin was associated with a risk of diabetes and more strongly associated with risks of cardiovascular disease and death from any cause as compared with fasting glucose. These data add to the evidence supporting the use of glycated hemoglobin as a diagnostic test for diabetes.

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