From the Guidelines
A hemoglobin A1c (HbA1c) level of 5.8% on two separate occasions indicates prediabetes, and this patient should focus on lifestyle modifications to prevent or delay progression to diabetes. According to the most recent and highest quality study 1, this level represents an increased risk for diabetes and cardiovascular disease. The patient should be counseled about effective strategies, such as:
- Weight loss if overweight
- Regular physical activity, aiming for 150 minutes of moderate exercise weekly
- A balanced diet low in refined carbohydrates and sugars No medications are typically prescribed at this stage unless other risk factors are present. The patient should have follow-up HbA1c testing in 6-12 months to monitor for progression, as recommended by 1 and 1. This level represents an average blood glucose of approximately 120 mg/dL over the past three months. Without intervention, approximately 5-10% of people with prediabetes progress to type 2 diabetes annually, as noted in 1. Early intervention with lifestyle changes can effectively prevent or delay progression to diabetes and reduce the risk of associated complications.
From the Research
HbA1c Readings and Diabetes Diagnosis
- A patient with two readings of HbA1c at 5.8% may be considered to have prediabetes, as defined by a glycated hemoglobin level (HbA1C) of 5.7% to 6.4% 2.
- Prediabetes is an intermediate stage between normal glucose regulation and diabetes, affecting 1 in 3 adults in the US and approximately 720 million individuals worldwide 2.
Risk of Progression to Diabetes
- Approximately 10% of people with prediabetes progress to having diabetes each year 2.
- Prediabetes is associated with increased risk of diabetes, cardiovascular events, and mortality 2.
Lifestyle Modification and Treatment
- Intensive lifestyle modification, consisting of calorie restriction, increased physical activity (≥150 min/wk), self-monitoring, and motivational support, decreased the incidence of diabetes by 6.2 cases per 100 person-years during a 3-year period 2.
- Metformin decreased the risk of diabetes among individuals with prediabetes by 3.2 cases per 100 person-years during 3 years 2.
- Structured exercise training, including aerobic exercise, resistance training, or both combined, is associated with HbA1c reduction in patients with type 2 diabetes 3.
Importance of HbA1c Measurement
- HbA1c is the main biomarker used to assess long-term glycaemic control in individuals with diabetes, and it correlates with the development of complications 4.
- HbA1c should not be interpreted in isolation; the measurement accuracy and other parameters, including treatment goals and comorbidities, need to be considered 4.
Dietary Patterns and Diabetes Management
- Certain dietary patterns, such as vegan, vegetarian, and Mediterranean diets, have been shown to improve glycemic control and management of type 2 diabetes 5.
- The Mediterranean dietary pattern demonstrated greater reduction in body weight and HbA1c levels and delayed requirement for diabetes medications 5.