Possíveis Diferenças Raciais em Níveis de HBA1c

Deu no Annals of Internal Medicine:

Este estudo avalia possíveis diferenças raciais em valores referenciais entre negros e brancos: aí pode existir um importante fator preanalítico de diferenças de resultados, com potencial, inclusive de se utilizar diferentes objetivos para HBA1c. Abaixo, o resumo:



Glucose-Independent, Black-White Differences in Hemoglobin A1c Levels: A Cross-sectional Analysis of 2 Studies: Background:

A previous study of participants with prediabetes found that hemoglobin A_1c (HbA_1c) levels differed between black and white participants with no differences in glucose concentration.

Objective:

To determine whether black–white differences in HbA_1c level are present in other populations and across the full spectrum of glycemia.

Design:

Cross-sectional, retrospective.

Setting:

Outpatient.

Participants:

1581 non-Hispanic black and white participants between 18 and 87 years of age without known diabetes in the SIGT (Screening for Impaired Glucose Tolerance) study and 1967 non-Hispanic black and white participants older than 40 years without known diabetes in the NHANES III (Third National Health and Nutrition Examination Survey).

Measurements:

HbA_1c levels, anthropometry, and plasma glucose levels during oral glucose tolerance testing.

Results:

Hemoglobin A_1c levels were higher in black than in white participants with normal glucose tolerance (0.13 percentage point [P < 0.001] in the SIGT sample and 0.21 percentage point [P < 0.001] in the NHANES III sample), prediabetes (0.26 percentage point [P < 0.001] and 0.30 percentage point [P < 0.001], respectively), or diabetes (0.47 percentage point [P < 0.020] and 0.47 percentage point [P < 0.013], respectively) after adjustment for plasma glucose levels and other characteristics known to correlate with HbA_1c levels.

Limitation:

The mechanism for the differences is unknown.

Conclusion:

Black persons have higher HbA_1c levels than white persons across the full spectrum of glycemia, and the differences increase as glucose intolerance worsens. These findings could limit the use of HbA_1c to screen for glucose intolerance, indicate the risk for complications, measure quality of care, and evaluate disparities in health.

Primary Funding Source:

National Institutes of Health and National Institute of Diabetes, Digestive, and Kidney Diseases