How to manage steroid-induced diabetes?

Management of Steroid-Induced Diabetes

For steroid-induced diabetes, NPH insulin administered in the morning is the preferred treatment to match the pharmacokinetics of glucocorticoids like prednisolone, which cause peak hyperglycemia 6-9 hours after morning administration. 1, 2

Understanding Steroid-Induced Hyperglycemia

• Glucocorticoids induce hyperglycemia through multiple mechanisms: impaired beta cell insulin secretion, increased insulin resistance, and enhanced hepatic gluconeogenesis 1, 2
• The hyperglycemic effect is most pronounced during the day (particularly afternoon and evening) and often normalizes overnight, even without treatment 2
• The degree of hyperglycemia directly correlates with the steroid dose - higher doses cause more significant elevations in blood glucose 1, 2
• Steroid-induced hyperglycemia occurs in 56-86% of hospitalized patients with and without pre-existing diabetes 3, 2

Monitoring Recommendations

• Blood glucose monitoring should be performed four times daily (fasting and 2 hours after each meal) 1
• Target blood glucose range should be 5-10 mmol/L (90-180 mg/dL) 1
• Peak hyperglycemic effects should be anticipated 6-9 hours after administration, making afternoon glucose monitoring particularly important 2

Treatment Algorithm

For Patients Not Previously on Diabetes Medications:

1. Initial Treatment:

   • For significant hyperglycemia, start with NPH insulin at 0.3-0.5 units/kg/day given in the morning to match the pharmacokinetics of glucocorticoids 3, 1
   • Higher doses may be needed for patients with higher steroid doses 1

2. Dose Adjustments:

   • Adjust insulin doses based on blood glucose patterns, with particular attention to afternoon and evening readings 1
   • As steroid doses are reduced, insulin doses should be proportionally decreased to avoid hypoglycemia 1, 2

For Patients Already on Diabetes Medications:

1. Oral Antidiabetic Agents:

   • Oral agents alone are typically insufficient to control significant hyperglycemia caused by high-dose steroids 1
   • Continue existing oral medications but add insulin therapy as described above 3, 1

2. Patients Already on Insulin:

   • Increase existing insulin doses by 40-60% or more, particularly prandial insulin 3
   • Add NPH insulin in the morning if not already part of the regimen 3, 1

Special Considerations

• For elderly patients or those with renal impairment, start with lower insulin doses (0.2-0.3 units/kg/day) 1
• Monitor for hyperosmolar hyperglycemic state, a life-threatening complication of severe steroid-induced hyperglycemia 1
• For long-acting glucocorticoids such as dexamethasone, long-acting basal insulin may be required to manage fasting blood glucose levels 3

Perioperative Management

• For patients requiring surgery while on steroids:
  • Target blood glucose in the perioperative period should be 100–180 mg/dL (5.6–10.0 mmol/L) 3
  • Hold oral glucose-lowering agents on the day of surgery 3
  • Give half of NPH dose or 75–80% doses of long-acting insulin 3
  • Monitor blood glucose at least every 2–4 h while NPO and dose with short- or rapid-acting insulin as needed 3

Common Pitfalls to Avoid

• Failing to anticipate the diurnal pattern of steroid-induced hyperglycemia, with peak effects in the afternoon and evening 1, 2
• Using only fasting glucose to monitor steroid-induced hyperglycemia (will miss the peak hyperglycemic effect) 2
• Not reducing insulin doses when steroid doses are tapered, leading to hypoglycemia 1, 2
• Relying solely on oral antidiabetic agents for high-dose steroid therapy 1