Vol. 15 •Issue 11
• Page 37
Diabetes in Older Adults
Consider Presentation, Functioning and More
By Sandra J. Kamp, NP, CDE
'Ellen" is 87 years young. She is a widow with an active social life and an independent lifestyle. Ellen exercises daily, eats a healthy diet to maintain a trim figure, loves to shop for the latest fashions, and recently modeled in a department store fashion show. She routinely engages in activities with her church, her friends and her family. To look at her, you would guess she is at least 10 years younger than her stated age.
"Louise" is Ellen's 83-year-old sister. She lives in an assisted living facility and receives 24-hour care. Louise, who is also widowed, has moderate vascular dementia. She requires maximum assistance for ambulation, receives meals in a group dining room and requires full assistance for all activities of daily living.
Although these two patients are "older," the contrast in their functional abilities and health status is dramatic. These women illustrate the wide-ranging characteristics of today's older adult population.
Optimal diabetes management for older adults must take into account diverse clinical features, including duration of diabetes, presence of related complications, comorbid illness and life expectancy. Functional variables to consider in the treatment plan include cognitive status, social support systems and level of independence in activities of daily living.1 Clearly, this diversity of characteristics presents challenges in setting and prioritizing treatment goals for older adults with diabetes.
Four Pillars
Irrespective of age, clinical condition and functional abilities, four strategies form the foundation of diabetes management: meal planning, physical activity, medication and self-monitoring of blood glucose.
As a treatment strategy for diabetes, meal planning (often referred to as medical nutrition therapy) promotes a caloric intake in line with personal energy requirements, attainment and maintenance of optimal weight and achievement of optimal cholesterol and blood glucose levels. Since blood glucose levels are largely driven by carbohydrate intake, meal-planning strategies typically focus on consistent day-to-day intake of carbohydrates, distribution of carbohydrate intake throughout the day, and minimal intake of fast-acting carbohydrates (simple sugars and sweets).
Activity and exercise are essential to improve glucose uptake, to decrease insulin resistance and to assist with any necessary weight loss, which in turn reduces insulin resistance. The standard exercise recommendation is 30 minutes of exercise 5 days per week.
When lifestyle interventions (meal planning and activity) do not achieve glycemic goals, medications must be added to the treatment plan. A biguanide is often the first therapy selected for overweight patients, while a sulfonylurea may be the first choice for a patient of normal weight. Drugs from other classes can be added when optimal dose titration of a single agent does not allow the patient to reach glycemic goals.
Home glucose monitoring provides the basis for evaluating self-management strategies and provides essential data for making pharmacologic decisions.
The ultimate responsibility for managing three of these four strategies rests with the patient. Effective diabetes management takes into account the patient's ability to learn and apply these strategies.
Guidelines for Older Adults
On the subject of diabetes management, clinical literature, research studies and practice guidelines abound. But few evidence-based guidelines specifically target the needs of older adults. As is true with research studies in general, older adults are often excluded from diabetes studies on the basis of age or comorbid conditions. Three published guidelines provide direction in caring for older patients with diabetes (Table 1).2-4
While the cited guidelines are well supported by evidence and expert consensus, keep in mind that guidelines of this type are directed to an older patient with a single illness. The reality, of course, is that many older adults have multiple diseases or conditions. Thus, treatment decisions need to reflect the relative risks and burdens of the overall treatment plan.5
Treatment Approach
When treating diabetes in older adults, common goals include control of blood glucose, optimal control of lipids and blood pressure, and promotion of self-management through education. For older adults with multiple comorbid conditions, practical management must be based on the relative risks and benefits of various treatment options.
The potential for harm must always be carefully weighed against the benefits of tight glycemic control. In older adults, severe hypoglycemic episodes may trigger arrhythmia, stroke or myocardial infarction.6 The risk of treatment-associated severe hypoglycemia increases with age, due in part to a diminished counterregulatory hormonal response. Altered renal function, slowed intestinal absorption, erratic food intake, inadequate hydration and polypharmacy are conditions that also increase the potential for hypoglycemia.
With older adults, hypoglycemic symptoms may not appear until blood glucose is well under 70 mg/dL, potentially limiting the time available to self-treat.7 Presenting symptoms tend to be neurogenic (unsteadiness, dizziness, poor concentration, confusion) rather than adrenergic (palpitations, sweating, tremors). Hypoglycemia symptoms in older adults can easily be attributed — in error — to coexisting diseases and drug regimens.
Recurrent hypoglycemia can diminish the normal counterregulatory response, leading to hypoglycemic unawareness (loss of warning symptoms of hypoglycemia). When this occurs, glycemic goals should be relaxed for at least 3 weeks to strictly avoid hypoglycemia and to promote the return of symptomatic hypoglycemia.7
Of the oral agents used to treat diabetes, sulfonylureas as a group are most likely to produce hypoglycemia in older adults. Chlorpropamide (Diabinese) is not indicated in this population due to its prolonged half-life and increased potential for hypoglycemia.3 Glyburide (Diabeta) has been associated with a greater incidence of hypoglycemia than other agents in the sulfonylurea class.4,7
The benefits of strict glycemic control should be evaluated in the context of life expectancy. The time required to realize the benefits of the treatment plan must be weighed against each patient's expected lifespan.
Immediate benefits of glycemic control may include reduced hyperglycemic symptoms — particularly increased urination, which can lead to urinary incontinence, sleep disturbance, dehydration and fall risk. Hyperglycemia can cause visual changes, with multiple adverse implications for independent function and safety. Increased blood glucose is also associated with platelet adhesiveness and increased risk for stroke, heart attack and claudication. Immediate benefits may also be noted in wound healing.
Macrovascular benefits are generally realized after 3 to 4 years of controlled hyperglycemia, hypertension and hyperlipidemia. In contrast, at least 8 years of glycemic control are needed to positively affect microvascular disease (retinopathy, renal disease).3
Comorbid conditions often complicate treatment choices. The treatment of one condition may have negative implications for a coexisting condition. Conditions particularly affected by diabetes treatment include heart failure, hypertension, renal disease and liver disease. Table 2 details specific considerations related to oral drug treatment.3,6,8
Apart from the prescribed treatment regimen, a patient's ability to follow the treatment plan is a critical factor in achieving glycemic goals. Consider each patient's ability to follow a meal plan, engage in exercise and activity, safely administer a medication regimen, and self-monitor glucose levels. Cognitive or functional impairments may require significant alteration in treatment goals and the subsequent treatment approach.
The patient's typical daily food intake should play an important role in therapy selection. Determine the patient's ability to afford, procure and prepare healthy food choices, and note any factors that affect appetite. Such factors may include inadequate dentition, social isolation, depression and coexisting conditions. Sulfonylureas may not be a safe choice for the older adult with erratic eating habits. Dietary prescriptions that focus on fresh fruits and vegetables may not be realistic for the patient who depends on other people for infrequent trips to the grocery store.
Comorbid conditions, functional limitations and motivation may affect the older adult's ability and willingness to engage in exercise. Exercise and activity recommendations may need to focus on small, incremental goals, such as gradually working up to 10 minutes of activity three times per day, rather than 30-minute exercise sessions daily. Aerobic targets may be adjusted to 50% to 60% of maximal heart rate.9 Low-impact or chair exercises may be an appropriate exercise recommendation.
When choosing a medication regimen, consider the cost of the drug, as well as its ease of administration and safety. Combination drug choices may simplify the drug regimen and reduce costs, once optimal dosages of each agent are determined. Clearly written medication schedules and organizers may improve medication accuracy and adherence for patients with complex treatment regimens or cognitive impairment. For older adults who take insulin, provide initial supervised practice and then periodically reassess technique. These observational moments help determine safety and the need for adaptive approaches. Prefilling of insulin syringes may be a strategy for older adults who require insulin and are unable to prepare an accurate dose but can safely self-inject.
Self-monitoring of blood glucose requires a certain degree of manual dexterity and visual ability to manipulate the equipment, as well as the cognitive ability to follow a testing schedule and interpret results. Glucose monitoring products are available with a range of features that accommodate patients with visual impairments and the need for technical simplicity.
Diabetes self-management education for older adults includes these principles:
use of adult learning principles
slowing the pace of instruction
incorporating memory aids
inclusion of key significant others and caregivers
re-evaluation of learning needs as circumstances change.
Table 3 outlines adaptive approaches to diabetes management for patients with altered self-care abilities.10
Applying Theory to Practice
Returning to the case examples, Ellen was recently diagnosed with type 2 diabetes after a routine annual exam. She attended a class to learn the basic principles of diabetes self-management. Ellen is willing and able to follow lifestyle recommendations for meal planning and activity. In fact, her current lifestyle choices are well aligned with best practice recommendations. Ellen is now taking glimepiride (Amaryl) daily, and she is self-monitoring her blood glucose once daily, alternating before and after meals. Ellen's treatment goals include a fasting blood glucose of less than 130 mg/dL and a hemoglobin A1C of less than 7%.
Louise relies on her caregivers for day-to-day diabetes management. In the assisted living setting, her meal plan is controlled, along with her medication administration and her glucose monitoring routine. She is 5 feet tall and weighs 102 pounds. She has mild renal compromise, controlled hypertension and hypothyroidism. Her highly variable appetite and calorie consumption are of particular concern. These place her at risk for hypoglycemia and undesired weight loss.
Louise is treated with repaglinide (Prandin) before her two largest meals of the day. The nursing staff has been instructed to withhold the drug if Louise is eating poorly and to increase the frequency of glucose monitoring. Given Louise's variable appetite and potential for malnutrition, dietary restrictions are limited to no concentrated sweets. Her goals for treatment include a blood glucose level of less than 180 mg/dL and a hemoglobin A1c of less than 8%. Members of the nursing staff routinely monitor her blood glucose three times per week. Control of blood pressure and lipids is a particular focus, given Louise's history of strokes and vascular dementia. Renal function is monitored with routine lab tests.
Putting It Into Practice
Older adults are a diverse patient population, and their diabetes treatment plans must address age-associated considerations as well as the highly variable characteristics they display. For all patients, the four cornerstones of therapy are dietary intervention, physical activity, pharmacotherapy and self-monitoring of blood glucose.
References
1. Suhl E, Bonsignore P. Diabetes self-management education for older adults: general principles and practical application. Diabetes Spectrum. 2006;19(4):234-240.
2. American Diabetes Association. Clinical practice recommendations 2007. Diabetes Care. 2007;30(Suppl 1):S9-10, S27.
3. American Geriatrics Society. Guidelines for improving the care of the older person with diabetes mellitus. J Am Geriatr Soc. 2003;51(Suppl 5):S265-S280.
4. Zarowitz BJ. Management of diabetes mellitus in older persons. Geriatr Nurs. 2006;27(2):77-82.
5. Boyd CM, et al. Clinical practice guidelines and quality of care for older patients with multiple co-morbid diseases: implications for pay for performance. JAMA. 2005;294(6):716-724.
6. Rendell, M. Type 2 diabetes management in older adults. Clinical Geriatrics. 2004;12(5):43-51.
7. Briscoe VJ, Davis SN. Hypoglycemia in type 1 and type2 diabetes: physiology, pathophysiology, and management. Clinical Diabetes. 2006;24:115-121.
8. Murphy JL, ed. Nurse Practitioners' Prescribing Reference. New York, N.Y.: Prescribing Reference, Inc.; 2007:144-146.
9. Franz, MJ, ed. A Core Curriculum for Diabetes Education: Diabetes in the Life Cycle and Research. 4th ed. Chicago: American Association of Diabetes Educators; 2001:103-128.
10. Williams AS. Talking meters: what's new? Diabetes Self-Manag. 2007;24(3):6-16.
Sandra Kamp is a gerontologic nurse practitioner and certified diabetes educator who provides diabetes care at Rush North Shore Medical Center in Skokie, Ill., and additionally focuses on diabetes and geriatrics in a private internal medicine practice. She is a member of the board of directors for the National Conference of Gerontological Nurse Practitioners.
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