Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents

CASE — A 61-year-old restaurant manager with type 2 diabetes returns for a routine office visit. Diabetes was discovered nine years ago on routine examination by his previous clinician when a random blood glucose was 193 mg/dL (10.7 mmol/L). The glycated hemoglobin (A1C) was 8.6 percent. The patient was treated initially with glipizide 5 mg every morning before breakfast.

Over the next two years, the dose of glipizide was increased incrementally to a dose of 10 mg twice daily before breakfast and supper. The blood glucose values improved and the A1C fell to the 7.3 to 7.8 percent range, the level depending, for the most part, on dietary adherence.

Three years ago, the A1C level rose to 8.4 percent and metformin was added. The initial dose of 500 mg twice a day with meals was increased rapidly to 1000 mg twice a day. The A1C fell to the 7.2 to 7.7 percent range.

You saw the patient for the first time one year ago. The A1C was 7.8 percent, and you suggested the need for additional medication to reduce the A1C value to <7.0 percent. The patient was reluctant to take another medication and said he would improve his diet. There is a buffet in the restaurant where he worked. Although he was eating three modest meals a day, he was nibbling constantly from approximately 4 PM until after midnight on crackers, peanuts, sausage, and cheese. He promised to limit himself to a modest snack at the end of each evening. The patient did not return during the intervening year but does so now because his blood glucose values have been rising despite his "improved" diet.

At the present time, the patient reports that he is no longer working in the restaurant and is following his diet. Breakfast is now two slices of whole grain bread and cappuccino. Lunch is a steak and a salad. Supper is often veal parmesan and a salad. He is no longer nibbling in the evening but does have a bedtime snack. He is pleased with his improved diet, notes that it has been a difficult transition, and is unwilling to make further changes.

He purchased an elliptical cross-trainer two months ago but has used it only three times. He did not bring his glucose diary but reports that his fasting blood glucose values at home are in the 150 to 165 mg/dL (8.3 to 9.2 mmol/L) range with no tests later in the day. He notes an increased frequency of urination, attributed to drinking three beers a day.

On examination, the blood pressure is 130/70 mmHg supine and 140/80 mmHg upright, the heart rate is 72 beats/minute, regular. His weight is 227 lbs; the body mass index (BMI) is 33.5 kg/m². Funduscopic examination reveals no evidence of retinopathy. The mucous membranes are moist. Examination of the chest, heart, and abdomen reveals no abnormality. The dorsal pedal and posterior tibial pulses are present. There is no edema. The feet exhibit mild cock-up deformities of the toes of both feet and a callus beneath the right first metatarsal-phalangeal joint. Light touch sensation is moderately reduced to the level of the distal calves. Vibration sensation is moderately reduced at the great toes and medial malleoli and is mildly reduced at the tibial tubercles. The deep tendon reflexes are absent in all extremities.

The patient's current medications are metformin 1000 mg twice daily, glipizide 10 mg twice daily, lisinopril 10 mg every morning, atorvastatin 40 mg daily at bedtime, aspirin 81 mg daily, a multivitamin once daily, and tadalafil 10 mg daily as needed.

Fasting laboratory studies reveal the following: glucose 220 mg/dL (12.2 mmol/L); sodium 141, potassium 4.6, chloride 102, and carbon dioxide 27 mEq/L; triglycerides 110 mg/dL (1.2 mmol/L), total cholesterol 169 mg/dL (4.4 mmol/L), high-density lipoprotein (HDL) cholesterol 40 mg/dL (1.0 mmol/L), and low-density lipoprotein (LDL) cholesterol 107 mg/dL (2.8 mmol/L); A1C 9.2 percent. The urinary microalbumin/creatinine ratio is within normal limits.

You conclude that the patient has not met glycemic targets for years, based on the A1C values, and now has persistent hyperglycemia on full doses of metformin and glipizide.

You advise the patient to start an additional diabetes medication. He replies that he has read about the current high cost of diabetes medications. He pleads for the least expensive medication that will achieve satisfactory glycemic management. Which additional medication do you add to the patient's current regimen?

●Pioglitazone 15 mg orally daily every morning. (See "Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents – A1".)

●Exenatide 5 micrograms subcutaneously twice a day before breakfast and supper. You schedule an appointment with the certified diabetes educator in your practice to instruct the patient in the technique of subcutaneous injection and in the use of this agent. (See "Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents – A2".)

●Sitagliptin 100 mg orally daily every morning. (See "Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents – A3".)

●Pramlintide 60 micrograms subcutaneously three times a day before meals. You schedule an appointment with the certified diabetes educator in your practice to instruct the patient in the technique of subcutaneous injection and in the use of this agent. (See "Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents – A4".)

●NPH insulin 20 units at bedtime (approximately 0.2 units per kilogram) as the initial dose. You schedule an appointment with the certified diabetes educator in your practice to instruct the patient in the technique of subcutaneous injection and in the use of insulin. (See "Interactive diabetes case 16: A 61-year-old patient with uncontrolled type 2 diabetes on two oral agents – A5".)