Certified Diabetes Care and Education Specialist (CDCES) Practice Exam

What might explain a discrepancy between an A1C of 6.8% and hospital glucose readings above 250 mg/dL?

1. Unmanaged diabetes for several months.

2. Recent improvement in glycemic control.

3. Recent insulin dosage increase.

4. Managed diabetes complicated by recent physiologic stress.

The correct answer is: Managed diabetes complicated by recent physiologic stress.

The reasoning behind selecting managed diabetes complicated by recent physiologic stress as the correct answer lies in understanding the relationship between A1C levels and blood glucose readings. An A1C of 6.8% typically indicates reasonably good long-term glycemic control, reflecting average blood glucose levels over the preceding two to three months. However, if hospital glucose readings are consistently above 250 mg/dL, this suggests a significant and recent change in blood glucose levels. Physiologic stress can greatly impact blood glucose levels, leading to hyperglycemia despite prior good management. Stressors such as illness, surgery, or emotional distress can trigger the release of hormones like cortisol and adrenaline, which can increase blood glucose levels acutely. This scenario can explain the contrast between the stable A1C and the elevated glucose readings seen during hospitalization. In contrast, unmanaged diabetes for several months would typically lead to a higher A1C, while a recent improvement in glycemic control or an increase in insulin dosage would likely not produce high glucose readings if the adjustments were effective. Thus, the presence of underlying stress is a vital factor that helps elucidate the discrepancy between the A1C and the higher hospital glucose levels.