hemoglobin a1c normal range in pregnancy

#HEMOGLOBIN A1C NORMAL RANGE IN PREGNANCY TRIAL#

In line with this notion, also RBC lifespan appears to be affected by several aging-associated changes, e.g.

Yet, glycemia and metabolic control change with age and several studies reported an increase of HbA1c in elderly non-diabetic individuals. It is well known, that among the elderly, the prevalence of impaired glucose tolerance, impaired fasting glucose, and type 2 diabetes is increased. Although age-dependent differences in HbA1c were reported before, clinical guidelines currently in use still rely on reference values without accounting for this influence of age. The UKPDS found an HbA1c of 5.4% in 195 healthy persons 25–65 years and 5.6% in 53 healthy persons > 65 years, in contrast the manufacturers reference was given with 5.2 +/− 0.47%. These reference values have not been subject to change since then. In this context is has to be noted that reference values for HbA1c were established in 1986 based on a small population of 124 nondiabetic individuals with a limited age range of 13–39 years. Given the essential role of HbA1c in the diagnosis and management of diabetes it is paramount to understand physiological changes of HbA1c levels in relation to age in order to provide reasonable cut-offs as well as reference values. Thus, HbA1c is considered a weighted measure of the average blood glucose levels during the past 120 days with plasma glucose levels from the preceding 30 days contributing substantially more (~ 50%) to the final result compared to plasma glucose levels from the past 90–120 days (~ 10%). Although older RBC are supposed to be exposed longer to blood glucose, younger RBC are more numerous. All RBC contribute to the measured level of HbA1c. RBC life span also appears to be reduced by hyperglycemia. However, measured HbA1c is also directly dependent on RBC life span, which may vary among individuals and among different age groups. The amount of HbA1c in the red blood cells (RBC) is directly related to the amount of plasma glucose as it is glycated in a non-enzymatic reaction.

#HEMOGLOBIN A1C NORMAL RANGE IN PREGNANCY TRIAL#

During the last decade, guidelines implemented HbA1c as equal diagnostic criterion besides measurement of plasma glucose for the diagnosis of diabetes as long as the HbA1c method is certified by the National Glycohemoglobin Standardization Program (NGSP) and is traceable to the Diabetes Control and Complications Trial (DCCT) reference assay. In daily practice, the advantages of HbA1c include less day to day variability during acute illness and greater convenience as fasting is not required compared to fasting plasma glucose measurements and oral glucose tolerance tests. Implementation of them into daily practice may improve patient care and diagnosis of diabetes and reduce the risk of misdiagnosis and subsequent overtreatment of diabetes in elderly patients.ĭetermination of glycated hemoglobin (HbA1c) is given a central role in the monitoring of antihyperglycemic therapy. As a consequence age-dependent reference values for HbA1c were derived from two large and well defined reference populations. The present study confirmed the previously observed increase of HbA1c with increasing age in non-diabetic individuals. Linear regression analyses confirmed the positive associations of HbA1c with age which was independent of BMI Conclusion ANOVA revealed up to 8.5 mmol/Mol (0.77%) or 7.3 mmol/Mol (0.68%) higher estimated mean levels of HbA1c in the oldest compared to the youngest age group in SHIP-0 or SHIP-trend, respectively. In both study populations an increase in HbA1c with age was observed. For people aged ≥60 years the URL was 47.5 mmol/Mol (6.5%). Reference intervals were derived from a healthy subpopulation with the upper reference limit (URL) for HbA1c of 42.1 mmol/Mol (6.0%) for individuals aged 20–39 years increasing to 43.2 mmol/Mol (6.1%) for individuals aged 40–59 years. Reference intervals for HbA1c were determined. Multivariable linear regression models were performed. HbA1c was determined by means of high-performance liquid chromatography. Methodsįour thousand two hundred sixty three participants from the Study of Health in Pomerania (SHIP-0) and 4402 participants from the independent study SHIP-Trend were included. The present study aimed to evaluate HbA1c levels in relation to age in two independent population-based cohorts and to derive age-specific reference intervals. However, this observation did not reach incorporation into daily clinical practice or the respective guidelines. Several studies report increased levels of HbA1c in nondiabetic elderly. Measurement of gylcated hemoglobin A1c (HbA1c) plays a central role in monitoring quality of antidiabetic therapy and in the diagnosis of diabetes.

Hemoglobin a1c normal range in pregnancy