Prediabetes a1c
Pro Research Analysisby 
Searched over 200M research papers for "prediabetes a1c"
Understanding Prediabetes A1C: Key Insights from Recent Research
Prediabetes A1C Definition and Transition to Diabetes
Prediabetes is often identified by measuring Hemoglobin A1c (A1C) levels, with values between 5.7% and 6.4% indicating an increased risk of developing type 2 diabetes. The transition rate from prediabetes to diabetes varies significantly across different populations and definitions. For instance, a study analyzing data from four large US cohorts found that the incidence rates for transitioning to diabetes were 4.2, 8.2, and 2.8 cases per 100 person-years for fasting blood glucose (FBG) levels of 100-125 mg/dL, 110-125 mg/dL, and A1C levels of 5.7-6.4%, respectively 1. This highlights the heterogeneity in diabetes risk among individuals with prediabetes.
Diagnostic Utility of A1C in Different Populations
The utility of A1C as a diagnostic tool for prediabetes and diabetes varies across different age groups and ethnicities. In obese children and adolescents, A1C alone has been shown to have low sensitivity and specificity for diagnosing prediabetes and type 2 diabetes, suggesting that it may underestimate the prevalence of these conditions in this population 2. Similarly, in a study of U.S.-based Africans, combining A1C with glycated albumin (GA) significantly improved the detection of prediabetes, identifying nearly 80% of individuals with the condition compared to 50% with A1C alone 5.
Contributions of A1C to Prediabetes Prevalence
A1C contributes significantly to the prevalence of prediabetes in the U.S. population. Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 showed that 21.7% of participants had A1C levels above the prediabetes cutpoint, making it a substantial marker for identifying at-risk individuals 3. Furthermore, the prevalence of prediabetes defined by A1C increased markedly from 1999 to 2010, indicating a growing recognition of this marker in diagnosing prediabetes 7.
Risk Factors and Progression to Type 2 Diabetes
Several risk factors are associated with the progression from prediabetes to type 2 diabetes. A study in southeast Michigan identified that a steady rise in A1C levels over four years was significantly associated with higher body mass index (BMI), family history of diabetes, age, and history of major adverse cardiovascular events (MACE) 6. This suggests that individuals with these risk factors may benefit from more aggressive preventative measures.
Prediabetes in Adolescents and Young Adults
The prevalence of prediabetes among adolescents and young adults in the U.S. is concerning, with 18% of adolescents and 24% of young adults affected. Impaired fasting glucose (IFG) was the most common marker, followed by increased A1C levels. The prevalence was higher in males and individuals with obesity, who also exhibited unfavorable cardiometabolic profiles, increasing their risk for type 2 diabetes and cardiovascular diseases 9.
Conclusion
A1C is a valuable marker for identifying prediabetes, but its utility varies across different populations and age groups. Combining A1C with other markers like glycated albumin can improve detection rates, especially in specific ethnic groups. Understanding the risk factors associated with the progression from prediabetes to diabetes can help in developing targeted prevention strategies. Continuous monitoring and tailored interventions are essential to address the growing prevalence of prediabetes and its associated health risks.
Sources and full results
Most relevant research papers on this topic
196-LB: Heterogeneity in Elevated Glucose and A1C as Predictors of the Prediabetes-to-Diabetes Transition—Framingham Heart Study, Multiethnic Study on Atherosclerosis, Jackson Heart Study, and Atherosclerosis Risk In Communities
Heterogeneity in elevated glucose and A1C levels predicts the transition from prediabetes to diabetes, with no clear explanation from body mass index or ethnic differences.
Meta-AnalysisUtility of Hemoglobin A1c for Diagnosing Prediabetes and Diabetes in Obese Children and Adolescents
Hemoglobin A1c is a poor diagnostic tool for identifying prediabetes and type 2 diabetes in obese children and adolescents due to its low sensitivity and specificity.
Observational Study
Rigorous Journal
Highly CitedContributions of A1c, fasting plasma glucose, and 2-hour plasma glucose to prediabetes prevalence: NHANES 2011-2014.
Fasting plasma glucose is the largest contributor to prediabetes prevalence in the overall population, followed by A1c and then 2-hour plasma glucose.
Observational StudyScreening for Diabetes and Prediabetes With Proposed A1C-Based Diagnostic Criteria
A1C screening can identify some patients with unrecognized diabetes and its complications, but is inadequate for identifying prediabetes, as lower glucose levels are more likely to indicate prediabetes.
Rigorous JournalHighly CitedA1C Combined With Glycated Albumin Improves Detection of Prediabetes in Africans: The Africans in America Study
Combining A1C with glycated albumin improves detection of prediabetes in Africans, detecting nearly 80% of those with the condition.
Observational Study
Very Rigorous JournalRisk factors associated with glycated hemoglobin A1c trajectories progressing to type 2 diabetes
A more aggressive preventative approach should be considered for patients with a family history of type 2 diabetes, high BMI, and year-to-year increase in HbA1c, regardless of normal or prediabetic hemoglobin A1c levels.
Observational StudySecular Changes in U.S. Prediabetes Prevalence Defined by Hemoglobin A1c and Fasting Plasma Glucose
U.S. prediabetes prevalence increased from 1999-2010 due to increases in A1C5.7, highlighting the need for continuous monitoring to identify high-risk individuals for diabetes prevention efforts.
Observational StudyVery Rigorous JournalHighly CitedImpact of hemoglobin A1c-based criterion on diagnosis of prediabetes: The Korea National Health and Nutrition Examination Survey 2011
The introduction of HbA1c criterion significantly increased the prevalence of prediabetes in Koreans, identifying individuals with different characteristics compared to those meeting fasting plasma glucose criteria.
Observational StudyRigorous JournalPrevalence of Prediabetes Among Adolescents and Young Adults in the United States, 2005-2016.
The prevalence of prediabetes in US adolescents and young adults is 18.0% and 24.0%, respectively, with impaired fasting glucose being the largest proportion of the condition.
Observational StudyHighly Cited983-P: Prediabetes A1C Is Associated with Metabolic Disease in Girls with PCOS and Obesity
A1c testing is less burdensome than OGTT and can identify girls with PCOS and obesity at increased metabolic disease risk, potentially benefiting from metformin.
Very Rigorous Journal