Can two hospitalizations with steroid treatment for surgery cause elevated Hemoglobin A1C (HbA1C) levels?

Steroid Administration During Hospitalization Can Cause Elevated HbA1c

Yes, two hospitalizations with steroid treatment for surgery can cause elevated HbA1c levels, particularly in patients with pre-existing diabetes or those at risk for diabetes. 1

Mechanism of Steroid-Induced Hyperglycemia

Steroids administered during hospitalization can significantly impact glycemic control through several mechanisms:

• Glucocorticoids induce insulin resistance in 56-86% of hospitalized patients, with or without pre-existing diabetes 1
• Steroids increase hepatic glucose production and decrease peripheral glucose uptake
• The hyperglycemic effect typically begins within 48 hours of steroid administration 2
• The pattern of hyperglycemia depends on the type and timing of steroid administration:
  • Morning prednisone causes afternoon/evening glucose peaks 1
  • Dexamethasone (longer-acting) can cause more prolonged hyperglycemia 1

Impact on HbA1c

HbA1c reflects average blood glucose levels over the previous 8-12 weeks. Two hospitalizations with steroid treatment can affect HbA1c in the following ways:

• Short-term impact: A single steroid course typically causes transient hyperglycemia lasting 1-5 days 3
• Cumulative impact: Multiple hospitalizations with steroid treatments can cause sustained hyperglycemia sufficient to elevate HbA1c
• Pre-existing glycemic control matters: Patients with baseline HbA1c ≥7% experience higher and more prolonged glucose elevations after steroid administration 3

Risk Factors for Significant HbA1c Elevation

The degree of HbA1c elevation depends on:

1. Baseline glycemic control: Patients with higher baseline HbA1c show greater glucose elevations after steroid administration 4, 3
2. Steroid dose and duration: Higher doses and longer courses cause more pronounced hyperglycemia
3. Type of steroid: Long-acting steroids (dexamethasone) have more prolonged effects than intermediate-acting ones (prednisone) 1
4. Insulin reserve: Patients with limited insulin secretory capacity (e.g., type 1 diabetes) are more vulnerable 5

Clinical Implications

• Stress hyperglycemia vs. undiagnosed diabetes: Elevated HbA1c (≥6.5%) after hospitalization may indicate previously undiagnosed diabetes rather than just transient stress hyperglycemia 1
• Follow-up monitoring: Even patients with normal HbA1c (<6.5%) who experience stress hyperglycemia should be monitored, as 60% may develop diabetes within one year 1
• Perioperative management: The American Diabetes Association recommends targeting HbA1c <8% for elective surgeries 6

Management Considerations

For patients requiring steroids during hospitalization:

• Monitor blood glucose levels for at least 48 hours after steroid administration 2
• Consider insulin therapy during steroid treatment to prevent hyperglycemia:
  • NPH insulin administered concomitantly with intermediate-acting steroids 1
  • Long-acting basal insulin for long-acting steroids like dexamethasone 1
• Adjust insulin doses based on glycemic patterns and anticipated changes in steroid dosage 1
• For patients without known diabetes who develop hyperglycemia, follow up with HbA1c testing to distinguish between stress hyperglycemia and undiagnosed diabetes 1

Common Pitfalls

• Underestimating hyperglycemic impact: Up to 70% of non-diabetic patients receiving high-dose steroids develop at least one blood glucose reading ≥10 mmol/L (180 mg/dL) 2
• Missing the pattern: Steroid-induced hyperglycemia often follows a predictable pattern based on steroid type and timing
• Inadequate monitoring: Failure to monitor glucose levels after steroid administration can lead to missed hyperglycemia
• Overlooking long-term implications: Stress hyperglycemia during hospitalization may indicate risk for future diabetes development