What is the recommended treatment for a 23-year-old with impaired fasting glucose (Hyperglycemia), HbA1c (Hemoglobin A1c) of 5.2, and trace ketones in urine?

Assessment and Management

This 23-year-old does not have diabetes and does not require pharmacologic treatment. The fasting glucose of 112 mg/dL indicates impaired fasting glucose (prediabetes), but the HbA1c of 5.2% is well within the normal range (<5.7%), and trace ketones are likely physiologic and not clinically significant in this context 1.

Diagnostic Interpretation

• Fasting glucose of 112 mg/dL falls in the impaired fasting glucose range (100-125 mg/dL), which indicates prediabetes 1
• HbA1c of 5.2% is normal (prediabetes is defined as HbA1c 5.7-6.4%) 1
• Trace ketones in urine are not concerning in a young, non-diabetic individual and likely represent normal physiologic variation from fasting, exercise, or low carbohydrate intake 1

The discordance between the mildly elevated fasting glucose and normal HbA1c suggests this patient does not have established diabetes or even consistent prediabetes. HbA1c reflects average glucose over 2-3 months and is more reliable than a single fasting glucose measurement 1.

Recommended Management Strategy

Lifestyle Intervention (Primary Treatment)

Intensive lifestyle modification is the cornerstone of treatment for impaired fasting glucose, targeting 7% body weight loss and at least 150 minutes per week of moderate-intensity physical activity 1.

• Refer to a structured behavioral counseling program focused on diet and physical activity 1
• Target at least 150 minutes per week of moderate-intensity aerobic activity (such as brisk walking) 1
• Include resistance training at least 2-3 times per week 1
• Aim for 7% reduction in body weight if overweight or obese 1
• Provide dietary counseling emphasizing a heart-healthy diet with reduced saturated fat, increased fiber, and portion control 1

Pharmacologic Therapy: NOT Indicated

Metformin is NOT recommended for this patient because:

• HbA1c of 5.2% is below the threshold (5.7-6.4%) where metformin may be considered 1
• The patient is 23 years old (metformin is primarily considered for those with BMI >35 kg/m², age <60 years, AND HbA1c 5.7-6.4%) 1
• A single elevated fasting glucose with normal HbA1c does not warrant pharmacologic intervention 1

Monitoring Plan

• Repeat fasting glucose and HbA1c in 3-6 months to confirm the diagnosis and assess progression 1
• At least annual monitoring for development of diabetes once prediabetes is confirmed 1
• Screen for and manage cardiovascular risk factors including lipids and blood pressure 1

Common Pitfalls to Avoid

• Do not initiate metformin based on a single elevated fasting glucose when HbA1c is normal—this represents overtreatment 1
• Do not ignore trace ketones as a sign of diabetes in a young person with normal HbA1c—physiologic ketonuria is common with fasting or exercise 1
• Do not assume diabetes is present without confirmatory testing showing either fasting glucose ≥126 mg/dL on two occasions or HbA1c ≥6.5% 1
• Do not neglect lifestyle intervention—this is more effective than any medication for preventing progression to diabetes (58% reduction in diabetes incidence) 1

Follow-Up Considerations

• If repeat testing confirms impaired fasting glucose (fasting glucose 100-125 mg/dL) or HbA1c rises to 5.7-6.4%, intensify lifestyle counseling and consider metformin only if additional risk factors are present (BMI >35 kg/m², family history of diabetes) 1
• Provide diabetes self-management education as an appropriate venue for prediabetes education and support 1
• Ensure follow-up counseling for lifestyle modifications, as ongoing support improves success rates 1