Distribution of Glycated Haemoglobin According to Early-Life and Contemporary Characteristics in Adolescents and Adults without Diabetes: The 1982 and 1993 Pelotas Birth Cohorts.
OBJECTIVE
Glycated haemoglobin (HbA1c), a marker of glucose control in individuals with diabetes mellitus, is also related with the incidence of cardiometabolic risk in populations free of disease. The aim of this study was to describe the distribution of HbA1c levels according to early-life and contemporary factors in adolescents and adults without diabetes mellitus.


METHODS
HbA1c was measured in adults aged 30 years and adolescents aged 18 years who are participants in the 1982 and 1993 Pelotas Birth Cohorts, respectively. Bivariate and multivariate analyses were performed to describe the HbA1c mean values according to early-life and contemporary characteristics collected prospectively since birth.


RESULTS
The distribution of the HbA1c was approximately normal in both cohorts, with a mean (SD) 5.10% (0.43) in the 1982 cohort, and 4.89% (0.50) in the 1993 cohort. HbA1c mean levels were significantly higher in individuals self-reported as black/brown skin color compared to those self-reported as white in both cohorts. Parental history of diabetes was associated with higher HbA1c mean in adults, while stunting at one year old presented an inverse relation with the outcome in adolescents. No other early and contemporary factors were associated with HbA1c levels in adults or adolescents.


CONCLUSIONS
We found a consistent relationship between HbA1c and skin color in both cohorts. Further research is needed to understand the role of genomic ancestry on levels of HbA1c concentrations which may inform policies and preventive actions for diabetes mellitus and cardiometabolic risk.
Post-graduate Program in Epidemiology, Federal University of Pelotas, Marechal Deodoro 1160, 3rd floor, 96020-220, Pelotas, Brazil.
Romina
http://orcid.org/0000-0002-6905-8767
R
Buffarini
International Center for Equity in Health, Federal University of Pelotas, Rua Marechal Deodoro, 1160 3rd floor, 96020-220, Pelotas, Brazil.
María Clara
MC
Restrepo-Méndez
Clinical Medical Department, Faculty of Medicine, Federal University of Pelotas, Rua Félix da Cunha 614, Centro, 96010-000, Pelotas, Brazil.
Vera M
VM
Silveira
CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Department of Medicine, School of Medicine, Lima, Peru.
Jaime J
JJ
Miranda
Post-graduate Program in Epidemiology, Federal University of Pelotas, Marechal Deodoro 1160, 3rd floor, 96020-220, Pelotas, Brazil.
Helen D
HD
Gonçalves
Department of Physiology and Pharmacology, Federal University of Pelotas, Campus Universitário s/n, Capão do Leão, 96010-900, Pelotas, Brazil.
Isabel O
IO
Oliveira
Post-graduate Program in Epidemiology, Federal University of Pelotas, Marechal Deodoro 1160, 3rd floor, 96020-220, Pelotas, Brazil.
Bernardo L
BL
Horta
Post-graduate Program in Epidemiology, Federal University of Pelotas, Marechal Deodoro 1160, 3rd floor, 96020-220, Pelotas, Brazil.
Denise P
DP
Gigante
Post-graduate Program in Epidemiology, Federal University of Pelotas, Marechal Deodoro 1160, 3rd floor, 96020-220, Pelotas, Brazil.
Ana Maria
AM
Menezes
Department of Nutrition, School of Nutrition, Federal University of Pelotas, Campus Anglo, Gomes Carneiro 1, 96010-900, Pelotas, Brazil.
Maria Cecília F
MC
Assunção
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001938:Brazil; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D015438:Health Behavior; D006801:Humans; D008297:Male; D044469:Racial Groups / Q000706:statistics & numerical data; D012307:Risk Factors; D012959:Socioeconomic Factors
D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human