HbA1C strongly predicts risk of developing T2D in Overweight adolescents JAMA

A recent retrospective cohort study conducted within a large California healthcare system has unveiled crucial insights into the escalating risk of type 2 diabetes (T2D) among adolescents grappling with overweight and obesity. The study, spanning from January 1, 2010, to December 31, 2019, scrutinized data from 74,552 adolescents aged 10 to 17, shedding light on the correlation between hemoglobin A1c (HbA1c) levels and T2D risk. The study found that T2D risk increased substantially in overweight and obese adolescents whose baseline HbA_1c was above 6.0% and the risk also varied on various factors.

The study results were published in the journal JAMA Network Open.

Over the past two decades, the surge in childhood obesity has paralleled an alarming rise in prediabetes and type 2 diabetes (T2D) among adolescents. The American Diabetes Association recommends screening at-risk adolescents based on BMI and additional factors, with HbA1c assessment proving practical and effective. Published findings reveal a significant increase in prediabetes among adolescents facing overweight and obesity, prompting an urgent need for tailored prevention strategies. Hence researchers conducted a study to assess T2D risk by examining HbA1c levels among this vulnerable demographic.

This cohort study, analyzed data from January 1, 2010, to December 31, 2019, within a large California healthcare

system, focused on adolescents aged 10 to 17 years with BMI at or above the 85th percentile. Baseline HbA1c, BMI categories, and various covariates were examined for incident T2D outcomes using Cox proportional hazard regression analyses.

Findings:

• Over the follow-up period, encompassing data abstraction and analyses from January 1, 2020, to November 16, 2023, 698 adolescents (0.9%) developed diabetes, with 626 (89.7%) specifically diagnosed with T2D.
• The overall T2D incidence stood at 2.1 per 1000 person-years, and the 5-year cumulative incidence was 1.0%.
• One of the standout findings was the substantial association between baseline HbA1c levels and the heightened risk of T2D.
• Adolescents with HbA1c levels above 6.0% experienced a remarkable increase in T2D risk.
• The 5-year cumulative incidence ranged from 0.3% to 28.5%, with each incremental increase in HbA1c correlating with a greater risk of T2D.
• Notably, the hazard ratio for the highest HbA1c category was an astonishing 71.9 (95% CI, 51.1-101.1), emphasizing the profound impact of elevated HbA1c on diabetes risk.
• Additional risk factors included the higher BMI category, older age, and female sex.
• The study identified the Asian or Pacific Islander race as an independent indicator of increased T2D risk.
• In contrast, Black race or Hispanic ethnicity did not exhibit a significant difference compared with White race.
• Stratified analyses underscored that the incremental risk associated with higher HbA1c was more pronounced for Asian or Pacific Islander and White adolescents than for their Black and Hispanic counterparts.

The study's findings hold substantial implications for public health, emphasizing the need for nuanced diabetes surveillance strategies tailored to the distinctive risk factors prevalent in different demographic subgroups. By identifying high-risk individuals based on HbA1c levels, BMI, age, sex, and race/ethnicity, targeted preventive interventions can be implemented, presenting a crucial step forward in the battle against the rising tide of diabetes among adolescents grappling with overweight and obesity. As this groundbreaking research paves the way for more focused and personalized approaches to diabetes prevention, it marks a significant milestone in the ongoing efforts to safeguard the health of our youth.

Further reading: Hoe FM, Darbinian JA, Greenspan LC, Lo JC. Hemoglobin A_1c and Type 2 Diabetes Incidence Among Adolescents With Overweight and Obesity. JAMA Netw Open. 2024;7(1):e2351322. doi:10.1001/jamanetworkopen.2023.51322