Insulin to control this patient\'s blood sugar?

A 52-year-old male with a history of diabetes returns to his physician’s office for review of his labs. His health maintenance labs show a hemoglobin A1c of 9.0, increased from 7.0 at his last visit. His current drug regimen includes glipizide and metformin. He reports that he takes his medications regularly, but his wife is concerned about his diabetes control. Which of the following labs would best indicate a need for insulin to control this patient’s blood sugar?

1.Anti GAD antibody
2.C-petide
3.Fasting blood glucose
4.IGF-1
5.Random blood glucose

Exlanation

Insulin-resistant diabetes, aka adult-onset or Type II, eventually becomes insulin dependent when overworked pancreatic beta cells stop producing insulin. One way to determine when insulin therapy is indicated is to check a C-peptide (Answer B). C-peptide is cleaved when pro-insulin is converted to insulin; normal ranges of C-peptide indicate endogenous production of insulin.