What is the recommended HbA1c screening criterion for diabetes?

• A. HbA1c in all adults over 25
• B. HbA1c in all ≥40 years with risk factors
• C. HbA1c in all ≥35 years, or <35 years who are overweight or obese
• D. HbA1c only if symptomatic

Answer: (C)

Screen people at a point when their risk starts to rise and use a test that doesn’t require fasting. HbA1c is a practical screening tool because it reflects average blood glucose over the past 2–3 months. The recommended approach is to screen all adults beginning at age 35, and to screen younger adults if they are overweight or obese, since excess weight increases diabetes risk. This captures both the age-related rise in risk and the impact of obesity on insulin resistance, making it the best criterion. The other options either start screening too early or too late, or rely on symptoms rather than screening asymptomatic individuals.