Spurious elevations in glycosylated hemoglobin (HbA1) secondary to hypertriglyceridemia.

Measurement of glycosylated hemoglobin (HbA1) is frequently helpful to clinicians in treating patients with diabetes, since a number of studies show that this reflects a reliable index of diabetic control over time. There are several methods of measuring HbA. The chromatographic method is the most frequently used and is the standard method for large demand. We recently encountered a patient with diabetes mellitus who had substantial lactescent plasma secondary to hypertriglyceridemia that falsely raised the HbA1 level. We examined the patient in detail and determined that triglyceride concentrations greater than 1,750 mg/dL would falsely raise the HbA1 levels. In vitro studies performed by adding lipemic plasma to a control sample confirmed this. Thus, spurious elevations in HbA1 can occur in patients with lactescent plasma. This would further complicate the already existing interrelationship between glucose intolerance and hypertriglyceridemia.