The Case of Miss Lizzie

By M.J. Henderson, NP

Diabetes is a progressive disease that, without treatment, can lead to vital organ damage and death. National statistical data show that about 20% of today's older adults have diabetes. With the epidemic of obesity in this country, these numbers will surely grow in the not so distant future.

Some of the well-known complications associated with diabetes are retinopathy, cardiovascular disease, neuropathy and nephropathy. These life-altering problems may manifest in the form of blindness, myocardial infarction (MI), cerebral vascular accident (CVA), amputation and renal failure.

It is well known that cardiovascular disease is the primary cause of death for the majority of older adults, diabetics included.¹ This fact begs the question: Do older adults — a population already at higher risk for CVA, MI and peripheral vascular disease — reap the benefits of aggressive diabetes control? The American Diabetes Association and the American Geriatrics Society say it is unclear whether diabetes patients older than 65 who already have complications will benefit from aggressive therapy.^1,2 Although control of hyperglycemia is important, greater benefits may occur from reducing all cardiovascular disease (CVD) risk factors rather than tight glycemic control alone.¹

The risk-benefit ratio for intensive (tight) control in the older adult may be different from the risk-benefit ratio for a younger person (i.e., hypoglycemia risk vs. decreased complications). The challenge is to avoid severe hypoglycemia that can be traumatic to the frail cardiovascular system of older adults with diabetes.¹ On the other hand, we must not ignore the patient who has chronically high blood sugars on the premise that he or she might have a hypoglycemic event.

The American Geriatrics Society recommends an HgbA1C goal of <7% for relatively healthy older adult diabetics with good functional status. For diabetes patients with a life expectancy of less than 5 years and for whom hypoglycemia would have a dire effect, an HgbA1C of <8% is acceptable. That translates to blood glucose levels of roughly 170 mg/dL to 205 mg/dL, which is far above the desired 80 mg/dL to 140 mg/dL target range used for most community dwelling older adults.^1,2

The ultimate challenge is to tailor glucose control to the specific patient and to avoid symptomatic hypoglycemia. In my experience, older adults with blood sugars of 80 mg/dL to 150 mg/dL generally feel better, are more cognitively intact and are less likely to fall.

Close supervision of all older adults with diabetes, regardless of living setting, is important to achieving better diabetes care outcomes and, hopefully, an improved quality of life.

Who Is in Charge?

The control of diabetes ultimately falls on the patient, with the health care provider as the coach. Success or failure is partly dependent on patient and provider education, cognitive and physical abilities of the patient, and the comfort level of both parties. Some providers are more aggressive than others, and some patients are more resistant than others. With the right match, the patient's health can benefit, and the provider's frustration levels can lessen.

Many treatment options are available for diabetes. The risks of treatment can be reduced to some extent, but all changes in medications and technology require consideration of new complications as well. Education is the key for both parties.

What Are the Options?

Each diabetes patient is different, and the frail older adult is no exception. The treatment regimen should be unique to each patient; trial and error are required to determine the right mix.

Many options are available today. First and foremost are diet and exercise. Obesity exists in epidemic proportions, and excess body fat impairs the muscles' ability to use insulin. This is known as insulin resistance, the precursor to diabetes.^1,3 Therefore, essential elements of optimal diabetes management are 30 minutes of exercise every day and a lower carbohydrate diet that includes a balance of fats and proteins.¹

In the pharmacotherapy realm, many choices are available: sulfonylureas (Glucotrol XL, Amaryl, Glynase, Diabeta, etc), alpha glucosidase inhibitors (Glyset, Precose), thiazolidinediones or TZDs (Avandia, Actos), biguanides (Glucophage) and meglitinides (Prandin, Starlix). The injectable medications include long-acting and short-acting insulin plus the incretin mimetics (Byetta, Symlin). These medications work mostly to affect postprandial blood sugar levels, thus lowering the HgbA1c with the added bonus of reducing body weight.^4,5 These medications offer obese patients with diabetes yet another option for better weight control.

The newest pharmacologic treatment option is the first inhaled insulin, Exubera. It is similar to fast-acting insulin but is in dry powder form. Exubera is to be inhaled no sooner than 10 minutes before the meal. The most notable risk factor is pulmonary problems, thus this drug is not a viable choice for people with pulmonary disease or people who smoke. Before prescribing this insulin, perform a pulmonary function test. Repeat this test at 6 months and annually. If the patients exhibits a 20% or greater decline from baseline in the FEV1, the drug should be discontinued.

Exubera is ideal for patients with type 2 diabetes who have not responded adequately to two-medication therapy (e.g., a sulfonylurea and a biguainide). It is also an option for type 1 diabetes patients, but it is not approved for children. Exubera costs approximately $3.79 to $5.00 dollars per day, depending on the dose needed.⁶

The cost of newer medications can be prohibitive for some patients, thus they are not an option for some older adults. Medicare Part D is still in the early stages, so only time will tell which diabetes medications will actually be available to the majority of older adult diabetes patients with this prescription coverage.

A single medication can act differently among various patients — especially older adults. NPs who treat older adults with diabetes must remain vigilant yet be unafraid to try new options. That being said, alter treatment choices appropriately for older adults with physical or mental limitations. Every effort should be made to optimize diabetes care in the older adult, regardless of living setting.

Some providers are afraid to start insulin because they believe oral medications are safer for older adults. This is incorrect. For example, sulfonylureas can cause blood glucose levels to fall precipitously, and some patients have such severe hypoglycemia episodes that they can pass out and fall, risking concussion and injury. Knowledge of daily fingerstick glucose levels before meals and at bedtime provides information about the norm for each patient.

For some patients, seeing the glucometer results is the only way they understand what diet is doing to their blood sugar. At the very least, the glucometer is a cognitive trigger that some action is required to prevent higher glucose levels or to correct for low glucose levels. It places the onus on the patient to check and act on the information.

Just like their younger counterparts, older people do not like to prick their fingers, so asking for multiple glucose readings a day may not be well received. A week's worth of four-times-daily glucose checks will provide a better picture of glucose pattern. As we all know, some patients like to follow instructions, and some do not. Some never diet and exercise, others are model patients, and others go to the extreme. The following case study illustrates how being too "good" can be a "bad" thing.

Miss Lizzie

"Miss Lizzie" is an 85-year-old former mathematics teacher. She has had type 2 diabetes for 6 years and has been taking glyburide (Glucovance) and metformin (Glucophage). She was 110 pounds at diagnosis but lost 15 pounds and now is a slim 95 pounds. She is 4 feet, 11 inches tall. Miss Lizzie told us she was afraid to eat because her fasting blood sugar was 140 mg/dL and her HgA1c was fluctuating from 7.3% to 8.9%. She had been "reading up on diabetes," therefore she was trying to lower her carbohydrate intake in the hope of lowering her glucose levels.

Miss Lizzie has a past medical history of breast cancer in 1979 and coronary artery disease with angioplasty in 1992, and she currently has hypertension, hyperlipidemia and hypothyroidism. Despite these diagnoses, she was in relatively good health.

When she came to our office, her list of medications included glyburide 5 mg daily, metformin 1,500 mg in divided doses, methyldopa (Aldomet) 500 mg twice daily, lisinopril (Zestril) 10 mg twice daily, diltiazem (Cardizem) 240 mg daily, metoprolol succinate (Toprol XL) 25 mg daily, clonidine patch (Catapres TTS) every week, atorvastatin (Lipitor) 10 mg daily, hydrochlorothiazide (Microzide) 12.5 mg twice a week, risedronate (Actonel) 35 mg once a week, Tums 600 mg daily and a multivitamin daily.

Miss Lizzie walks four times a week on her treadmill, does housework daily and gardens whenever the weather is good. She is widowed and lives alone but has grown children and grandchildren in the area.

Miss Lizzie's food intake changed as her diabetes progressed. A typical daily menu started with a breakfast of banana and English muffin, along with tea. For lunch, she ate one slice of bread with turkey and one slice of cheese, raw vegetables and water. Dinner was fish or chicken, vegetables, salad and water. Her evening snack was piece of fruit and cup of dry cereal! Miss Lizzie was the diabetes educator's dream patient — except that she was starving herself! She was trying so diligently to watch her diet that she was afraid to eat the "wrong" food and cause "abnormal" blood sugars (>99)!

Miss Lizzie was losing weight, and she was hungry all the time. Her abstemious diet was not working — primarily because her pancreas was failing. No matter what she ate, her glucose level went up. She was already taking metformin 500 mg in the morning and 1,000 mg at night, along with glyburide 5 mg daily. So we added acarbose (Precose) 50 mg daily at breakfast to slow the absorption of carbohydrates, thus lowering the glucose level postprandially. This made her kidneys unhappy. Her blood urea nitrogen (BUN) went up to 30, with the creatinine holding at 1.0. We decided to discontinue the acarbose and the glyburide and go with repaglinide (Prandin) 2 mg, tablet three times a day to cause the beta cells that were still functioning in the pancreas to release insulin.

We then increased the repaglinide (Prandin) to tablet at breakfast and 2 mg at lunch and dinner. The HgbA1c still fluctuated, from 7.6 to 7.3 to 8.5 to 7.9. As the HgbA1c changed, so did her medication doses. We went up to tablet of repaglinide for breakfast, 2 mg for lunch and 4 mg for dinner, along with metformin 500 mg in the morning and 1,000 mg at night. Her HgbA1C did not cooperate. It rose to 8.8, so we increased her repaglinide to 4 mg three times daily.

No success. The blood sugars were about 200 mg/dL and did not come down. Her BUN and creatinine did not improve, so we decided to go with insulin. She was eager to learn about it. She had no problem with injections in her abdomen, but she did report that her fingers got rather sore from all the testing. We chose Lantus insulin because it is long acting and it is injected once a day at bedtime. We started with a low dose of 8 units at bedtime. Miss Lizzie was still taking Prandin and Glucophage — and following her carefully controlled starvation diet. Her blood sugars plummeted to 58, 69 and 60 at 4 a.m. and at breakfast.

We reduced the dose of Lantus to 6 units at bedtime and then down to 5 units. Miss Lizzie was still going low in the middle of the night and early morning. We then changed the Lantus to breakfast dosing. Our thought was that if she were to become hypoglycemic, she would at least be awake and hopefully able to do something about it. After changing the insulin dose to the morning, Miss Lizzie experienced higher fasting blood sugars and dipped low 5 or more hours after taking the Lantus, which peaks at about 5 hours and lasts for 24 hours. Once again, our strategy failed.

We discontinued Lantus and the repaglinide because they were lowering Miss Lizzie's blood glucose levels too much after meals. We switched to a 70/30 NovoLog mix pen — 70% Novolin (longer-acting NPH type insulin) mixed with 30% NovoLog (very short-acting insulin). We tried 8 units before breakfast and 6 units before dinner. Finally, success! With blood sugars in much better control, Miss Lizzie was able to change her diet to allow more carbohydrates. She was happy to be eating better — with the bonus of not being hungry all the time.

Today, Miss Lizzie is walking faithfully four times per week and maintaining her weight at 100 pounds. She remains the model patient. She still strives for perfection, but she is also likes to eat "those sweet dessert goodies at church every now and then." Her HgbA1c is now 7.4, which is certainly acceptable given all her preexisting conditions. She is definitely enjoying life more and has more energy.

Miss Lizzie looks and feels much better. She knows what to eat and when, so the quality of her life has improved tremendously. She has benefited greatly from insulin teaching and diet instructions.

There are two morals to this story: Insulin is a gift, not a punishment. And sometimes, being too good is bad for your health! Miss Lizzie knows this now. v

References

1. American Diabetes Association. Standards of medical care in diabetes. Diabetes Care. 2006;29(Suppl 1):S4-S42.

2. Reuben DB, et al. Geriatrics at Your Fingertips 2006-2007. 8th Ed. New York, N.Y.: The American Geriatrics Society; 2006; 62-65.

3. Dinsmoor RS. Healthy aging with diabetes. Diabetes Self Management. 2006;23(1):20-22.

4. Karl DM. Learning to use pramlintide. Practical Diabetology. 2006,:25(1):42-46.

5. Morello M, Edelman SV. Exenatide: a novel approach for patients with type 2 diabetes. Practical Diabetology. 2006:25(1):6-18.

6. Inhaled insulin (Exubera). The Medical Letter. 2006;48(1239):57-58.

M.J. Henderson is a gerontological nurse practitioner in a private endocrinology practice in Los Gatos, Calif. She is a member of the ADVANCE for Nurse Practitioners editorial advisory board and a past president of the National Conference of Gerontological Nurse Practitioners.