Interactive diabetes case 2: Switching from oral agents to insulin in type 2 diabetes

CASE — A 56-year-old woman is referred to you for management of type 2 diabetes.

Nine years ago the patient experienced three to four months of polyuria, polydipsia, nocturia, dry mouth, and blurred vision. She had habitually consumed large quantities of orange juice and ginger ale and had increased consumption severalfold when polydipsia appeared. She weighed 188 pounds, was 5' 5" tall, and had a body mass index (BMI) of 31.3 kg/m². A random glucose level was 237 mg/dL (13.2 mmol/L) and the glycated hemoglobin (A1C) was 10.7 percent. The patient was treated for diabetes with a no-concentrated sweets, low-fat diet, including substitution of diet beverages and water for juices and sodas, and with glipizide 5 mg by mouth once daily. Over the next six months, the A1C fell to 7.9 percent, and the patient's symptoms resolved.

Over the ensuing years, the patient's weight increased to 199 pounds, the BMI increased to 33.1 kg/m², the A1C level rose, and the use of oral agents increased. At the present time she takes glipizide 10 mg by mouth twice daily and metformin 1000 mg by mouth twice daily. The fasting glucose level is consistently 150 to 160 mg/dL (8.3 to 8.9 mmol/L), and the premeal values are in the 200 to 230 mg/dL (11.1 to 12.8 mmol/L) range. The A1C is now 9.7 percent. She eats three meals daily, follows her diet, and counts carbohydrates. The registered dietitian confirms that the patient is doing all of this reasonably well.

The patient has read about the current high cost of diabetes medications. She emphasizes that she wants the least expensive medication that will achieve satisfactory metabolic control. There is no evidence of atherosclerotic cardiovascular disease, congestive heart failure, or chronic kidney disease.

You conclude that the patient is a secondary failure on oral agents and recommend the initiation of insulin therapy.

How would you manage the patient at this time?

●Add NPH insulin 20 units subcutaneously daily at bedtime. (See "Interactive diabetes case 2: Switching from oral agents to insulin in type 2 diabetes - A1".)

●Add glargine insulin 20 units subcutaneously daily at bedtime. (See "Interactive diabetes case 2: Switching from oral agents to insulin in type 2 diabetes - A2".)

●Add insulin 70/30 (a mixture of NPH insulin and regular insulin in a 70:30 ratio) 20 units subcutaneously daily before breakfast. (See "Interactive diabetes case 2: Switching from oral agents to insulin in type 2 diabetes - A3".)

●Add NPH insulin 20 units subcutaneously daily before breakfast. (See "Interactive diabetes case 2: Switching from oral agents to insulin in type 2 diabetes - A4".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Type 2 diabetes (The Basics)")

●Beyond the Basics topics (see "Patient education: Type 2 diabetes: Overview (Beyond the Basics)")