BACKGROUND: Anemia is known to cause spurious hemoglobin A1c (HbA1c) results. The effect of menstruation on HbA1c was tested by correlating it to FPG in non-anemic premenopausal and in menopausal women.
METHOD: Non-diabetic, non-obese middle-aged Caucasian women were classified as premenopausal or menopausal. Hemogram, FPG, and A1c results were obtained.
RESULTS: Hemoglobin concentrations were lower in the premenopausal group. FPG showed a poor correlation to A1c value overall (r = 0.251, p = 0.001) which was improved by multiplying the A1c % by the total hemoglobin concentration to create an absolute A1c value (r = 0.362, p = 0.000). When the data was sorted by menopause status, the correlation of CONCLUSIONS: FPG to Absolute A1c improved (r = 0.463, p = 0.000) in the menopausal women, but remained low (r = 0.283, p = 0.005) in the premenopausal women.
Menstruation may be a significant factor affecting the accuracy of A1c concentrations.
Related links
Details
Title
Cessation of menstruation improves the correlation of FPG to hemoglobin A1c in Caucasian women