What is the significance of an elevated Hemoglobin A1c (HbA1c) level of 5.9, indicating Impaired Glucose Regulation?

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Last updated: May 8, 2025View editorial policy

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From the Guidelines

An A1c level of 5.9% indicates prediabetes, and individuals with this level should be informed of their increased risk for diabetes and cardiovascular disease. According to the study by 1, individuals with an A1C of 5.7–6.4% are at high risk for future diabetes, and this risk increases disproportionately as A1C rises.

Key Recommendations

  • Increase physical activity to at least 150 minutes of moderate exercise per week, such as brisk walking, swimming, or cycling, as suggested by 1 and 1.
  • Adopt a balanced diet rich in vegetables, lean proteins, and whole grains while limiting refined carbohydrates, sugary foods, and processed items.
  • Aim to lose 5-7% of body weight if overweight, as even modest weight loss can significantly improve insulin sensitivity, as noted in 1.
  • Monitor blood sugar regularly with a home glucose meter to track progress.
  • Stay well-hydrated and get adequate sleep, as both affect blood sugar regulation.

Rationale

The studies 1 and 1 emphasize the importance of lifestyle modifications in preventing progression to type 2 diabetes. By focusing on these changes, individuals can effectively lower their A1c levels and reduce their risk of developing diabetes and cardiovascular disease.

Follow-up

The healthcare provider should recheck the A1c level in 3-6 months to assess if these interventions are working or if additional steps are needed, as recommended by 1. This follow-up is crucial in determining the effectiveness of the lifestyle modifications and making any necessary adjustments to the treatment plan.

From the Research

Elevated A1c 5.9 Education

  • The study 2 found that approximately 90% of individuals with elevated A1C levels had fasting glucose ≥100 mg/dl, and that older age, male sex, non-Hispanic black race/ethnicity, hypercholesterolemia, higher BMI, and lower attained education were significantly associated with having a higher A1C level.
  • Another study 3 discovered that an association exists between higher levels of A1C and peripheral arterial disease, even among patients without diabetes, and that individuals with A1C levels ≥5.3% should be targeted for aggressive risk factor reduction.
  • The relationship between HbA1c level and cardiovascular disease was also investigated in study 4, which found that low baseline glucose and HbA1c were positively, but not significantly, associated with mortality, whereas low average fasting glucose and HbA1c were strongly and significantly associated with incident CVD and mortality.
  • A community-based peer-led diabetes self-management program was found to be effective in improving depression, symptoms of hypoglycemia, communication with physicians, healthy eating, and reading food labels in patients with type 2 diabetes, even in those without elevated A1C 5.
  • Study 6 determined that more than half of type 2 diabetes outpatients do not meet the recommended A1C and blood pressure target values, and that being female, black, young, and an insulin user were the main determinants of poor glycemic control.

Risk Factors and Associations

  • Elevated A1C levels are associated with various risk factors, including older age, male sex, non-Hispanic black race/ethnicity, hypercholesterolemia, higher BMI, and lower attained education 2.
  • Higher A1C levels are also associated with peripheral arterial disease, even among patients without diabetes 3.
  • Low average fasting glucose and HbA1c are strongly and significantly associated with incident CVD and mortality 4.

Education and Management

  • Community-based peer-led diabetes self-management programs can be effective in improving various aspects of diabetes management, even in patients without elevated A1C 5.
  • Individualized treatment and education are necessary to overcome therapeutic inertia and target treatment of patients on an individual basis 6.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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