2.20 Glycemic Control at the Diabetes Planned Visit

Diabetes Planned Visit Notebook

Diabetes planned visits address several health topics of concern to the diabetic patient, including glycemic control. This document is a decision support aid for controlling blood glucose levels.

Glycemic Control

  • Effects of HgbA1c changes on health:
    • ↑ 1% → ↑ cardiovascular disease 28%.
    • ↓ 1% → ↓ heart attack rate 14%.
    • ↓ 1% → ↓ diabetes related deaths 25%.
    • ↓ 1% → ↓ kidney, eye or nerve damage 30%.
  • Each oral agent lowers HgbA1c about 1%.
  • Most patients eventually require insulin.
  • 50% by 6 years; 80% by 9 years.
HgbA1CAverage Blood Sugar
6135
7170
8205
9240
10275
11310
12345
13380
14415

Steps to control Blood Glucose

  1. Find out patient's understanding and priorities.
  2. If diet questions or High BMI: Summa dietitian, Summa DM Center, or U of A diet study.
  3. Optimize oral agents and follow Q2-4 weeks.
  4. Prepare patient for insulin treatment: FMC nurse visit for DM education, Summa DM Center.
  5. Start insulin.

Medication selection

HgbA1c >7%, but <8%

  • Most patients will require two agents for long-term control.
  • Choosing sulfonylurea or metformin initially is not particularly important.
    • Sulfonylurea—more rapid onset than metformin.
      • Hypoglycemia with glipizide (Glucotrol) than glyburide (Diabeta, Micronase).
    • Metformin (Glucophage)—lower risk of hypoglycemia, less weight gain.

HgbA1C > 8%

  • Start sulfonylurea (glipizide, glyburide), rather than metformin, for more rapid onset.

HgbA1c >9.0%

  • Combination therapy will likely be required, may not reach AIC <7.
    • Consider metformin + glyburide (Glucovance) or glipizide + metformin (Metaglip).

Hemoglobin A1C >10% 

  • Start insulin.

Oral agents

  • If HgbAIC ≥9, unlikely to reach goal with oral agents.
  • Sulfonylureas show full effect within 1 to 2 weeks.
  • Metformin shows full effect in 4 weeks.
  • TZDs may not reach full effect for several months.

Metformin (Glucophage)

Avoid metformin in patients who are at risk for lactic acidosis.

  • Females serum creatinine >1.4, males creatinine >1.5.
  • Estimated creatinine clearance <60 cc/min.
  • Congestive heart failure.
  • Hypoxia.
  • Take with food to avoid GI symptoms of diarrhea, nausea, vomiting.
  • Start 500mg-850mg in the morning with meals
    • Increase by 500-850 mg every 2 weeks.
    • Split the dose to b.i.d.
    • Usual maintenance is 850 mg b.i.d.
    • Max benefit at 2,000 mg daily.
  • If iHgbA1C >7 after 4 weeks at maximal doses, add a second agent.
  • If HgbA1c >7 after 4-12 weeks of max metformin plus a second agent, switch to different agent
    • i.e, substitute TZD for sulfonylurea, or vice versa.

Thiazolidinediones (TZDs) (pioglitazone, rosiglitazone)

Contraindications:

  • NYHA class 3 or 4 CHF.
  • ALT >1.5 the upper limit of normal.
  • Monitor ALT, AST and bilirubin periodically.
    • If ALT is greater than 1.5 to 2 times higher than the upper limit of normal during therapy, retest in a week, then weekly until it returns to normal.
    • If ALT ≥3 X ULN discontinue TZD.
  • Not recommended as monotherapy.
  • May be used with sulfonylurea or metformin.
  • Monitor hemoglobin A1C at three and at six months.
  • Discontinue TZD if HgbA1c >7.

Starting Insulin 

  • Glargine (Lantus) in the morning (or at bedtime).
  • Initial glargine dose: 10 units daily or 2 units for each 20 mg above 100mg.
  • Titrate weekly based on last 2 FPG values:
    • 2 units for each 20mg above 100mg
      i.e., FPG 140 → increase 4 units; FPG 200 → Increase 10 units.
    • No increase in dose if BG <72 or documented severe hypoglycemia.
  • Avg doses to achieve a FPG of 100 mg = 0.45-0.5 units/kg.
Current as of January 2008
Internet Citation: 2.20 Glycemic Control at the Diabetes Planned Visit: Diabetes Planned Visit Notebook. January 2008. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/professionals/education/curriculum-tools/diabnotebk/diabnotebk220.html