If you were asked to name a medical disease fairly common among the elderly and poor that can be very complex to manage in an outpatient clinic, how would you respond?
Hypertension? It certainly is common. Heart disease? That can be very complex. What about diabetes in the elderly? This disease has its peak age of incidence in the elderly. Diabetes is always a difficult disease to control, especially in the adolescent group. But the elderly are probably the second most difficult group to successfully manage. Controlling diabetes in the elderly also is complicated by a habituated life style, longstanding food practices, and by misconceptions toward health care. For example, many elderly people know nothing of the relationship between diet and the etiology and control of their disease.
The true incidence of diabetes in the elderly is not known. A 1969 study in London placed the peak age of diagnosis of diabetes in the 50 to 69 year old age range.1 Diagnosing diabetes in the elderly is difficult and often is missed because the classic symptoms frequently are absent. For example, hyperglycemia can exist without glycosuria. Those signs and symptoms that are caused by diabetes often are attributed to some other affliction common to the elderly, such as visual alterations.
The majority of diabetics among the elderly are the Type II (noninsulin dependent) diabetics and are typically overweight. Although some Type II diabetics may require insulin for control, most secrete a sufficient amount of insulin, but for some reason don't utilize it well.
The Type I (insulin dependent) diabetics among the elderly, who secrete insufficient amounts of insulin and require replacement therapy, represent a smaller percentage of the total diabetic population. In a small number of cases, diabetes will be associated with the use of hyperglycémie drugs such as steroids, nicotinic acid, and the thiazide diuretics.2 These drugs are used commonly by the older population.
As teachers/ clinicians we are often the primary caretakers of the elderly diabetic in our clinics; the burden falls upon us to assist our patients in controlling their disease. Accomplishing the task requires that we consider the patient's attitude toward self, life, and health care. We also need to consider our own attitudes and skills - don't assume that simple teaching ensures reception, comprehension and, compliance on the part of the patient. We should strive to include the patient's participation in his/ her care as much as possible. One very good way to do this is by providing some means of biofeedback. To function effectively in this role as nurses requires good listening ability, skill in the teaching-learning process, and knowledge of the pathophysiology of diabetes, and knowledge of the physiology of normal agerelated changes.3
Detection of Diabetes
All nurses should be familiar with the classic signs of diabetes: polydipsia, polyuria, polyphagia, weight loss, and (possibly) nausea and vomiting. In the elderly diabetic, however, these classic signs may present quite subtly or may be completely absent.4 The discovery of diabetes in the elderly often is a serendipitous finding that occurs during a hospitalization, eye exam, screening test, or medical work-up for a nonspecific complaint, such as fatigue. Normal diagnostic procedures apply to the elderly whenever diabetes is suspected. These include evaluation of symptoms (classic or atypical), interpretation of physical exam findings (evidence of neuropathy or retinopathy vs. normal aging changes), and evaluation of laboratory results (ageadjusted serum glucose or glucose tolerance test results).
A major obstacle in the detection of diabetes in the elderly is that it can mimic so many other problems the elderly commonly experience. In the outpatient setting, the patient may voice concern about a problem related to any of several body functions. Nocturnal diarrhea, decreased libido, urinary retention, and orthostatic hypotension are common and can result from various disorders. The wise nurse will recognize, however, that these disorders also can be the only symptoms of diabetes in the elderly.5
Additional symptoms of diabetes also can be related to motor and sensory neuropathies with complaints such as numbness, burning, tingling, or weakness in the extremities. In many instances, a patient's family may state concern over subtle mental changes, chronic fatigue, or lethargy. A crucial point to consider in dealing with the elderly patient who is a possible diabetic is the relativity of changes, (see table)
Because most elderly diabetics are Type II, and are therefore not prone to ketosis, diabetic ketoacidosis is not the problem that it is in other age groups. But they are susceptible to a different type of coma - hyperosmolar coma - which is most common in people over age 60. The relative insulin deficiency of Type II diabetes can produce a very marked hyperglycemia - 400-2000 mg%. This causes an intense glucose osmotic diuresis that leads to severe fluid loss, electrolyte imbalance, and death in over 50% of the cases. Death usually results from thrombus formation due to greatly increased serum viscosity.8 Occasionally, hyperosmolar coma is the first indication of the existence of diabetes in an elderly person. As clinicians, we should always be alert to the possibility of impending coma when the blood glucose level exceeds 400-500 mg%. Treatment of coma requires immediate hospitalization with fluid and electrolyte replacement and control of hyperglycemia.
The testing of urine for glycosuria has its most practical application as a screening tool for the general population. It cannot be considered reliable, however, as a testing means for achieving control of diabetes in the elderly. The problem with this test is that normal aging changes cause a decrease in the glomerular filtration rate (GFR). This decreased GFR causes a high renal threshhold for glucose in the elderly. In other words, less filtration of excess glucose in the gì o menali means less spillage of glucose into the urine, thereby making urine testing for glucose an inadequate test. Glucose levels may reach or exceed 300 mg% before there is any trace in the urine in many of the elderly. Glycosurie testing is easy and inexpensive and can aid in discovering new diabetics in the elderly, but it should be used with a recognition of its limitations in this age group.
There is controversy over what the target glucose level for control should be in the elderly. Somediabetologists recommend a blood glucose level of less than 150 mg% while others ignore the glucose level and treat any symptoms. Advocates of the latter approach cite research that seems to indicate that complications occur in spite of the level of glucose control.4 Data contrary to this line of thinking come from research done on motor and sensory nerve conduction velocity. This research has demonstrated that motor nerve neuropathy is related to hyperglycemia and sometimes can be reversed with control of hyperglycemia.9
Perhaps the most sensible solution at this time is a middle-of-the-road approach. One successful nursingoperated clinic system seeks glucose levels of between 125-225 mg% in their elderly patients.10 Symptoms are treated and/ or referred to the back-up physician. The goal is a level of control that keeps the patient functioning and comfortable. The glucose tolerance test (GTT) is the standard diagnostic test for suspected diabetes in any age group but it is subject to many errors and influences and is often difficult to administer to an older person. The following are three of the reasons for this test's questionable use in the elderly:
1. The average elderly person takes at least five medications each day. Drugs that often produce abnormal GTT results include estrogen, steroids, salicylates, caffeine, nicotine, thiazide diuretics, and chloropromazine.10
2. The diet required three days prior to the test may be impractical for many elderly people.
3. Infection, surgery, or emotional problems can affect results. If a GTT is not done properly, it is of no value.
Random blood sugar greater than 200 mg% on at least two occasions is diagnostic of diabetes. A general rule of thumb that many clinicians use when evaluating glucose levels is to add 10 mg% for each decade past age 50. Those persons with glucose levels between 140-200 mg% and without symptoms should be considered as having some degree of impaired glucose intolerance and to be at risk for developing either Type I or Type II diabetes.
The clinician should keep in mind that glucose values should be adjusted for age. As we age, we utilize glucose less efficiently, and there is a normal delayed secretion of insulin in response to glucose load.
SIQNS-SYMPTOMS INDICATING POSSIBLE DIABETES IN THE ELDERLY
Home Glucose Monitoring
A new product has been gaining acceptance for home glucose monitoring recently. The Chemstrip bG by Bio-Dynamics of Indianapolis have tested more accurately than Dextrostix and slightly more accurately than the Dextrostìx-Eyetone method for measuring glucose levels. Repeated testing has shown this reagent strip to correlate closely enough to simultaneous serum glucose levels to provide accuracy in monitoring glucose levels.11
This product has practical applications for the home and for the outpatient setting because it is relatively inexpensive and accurate. It does not require any type of meters or calibrated devices for reading and can be used with good results by most elderly diabetics.
The importance of a simple but reliable method of home glucose monitoring is that it provides immediate feedback to the patient. This feedback stimulates improved compliance by most patients because they can take a much more active part in their plan of care. Adherence to diet and weight control is reinforced constantly when targeted glucose levels are achieved. Home monitoring without the assistance of family or friends is not possible in elderly patients who are confused or visually handicapped.
A recently developed test for glucose, the Glyco-Hemoglobin assay, gives an accurate estimate of glucose levels over a two- to three-month period by measuring hemoglobinbound glucose in the red blood cells. The more glucose available for binding over the red cell's life span the higher the glyco-hemoglobin level will be. This test is not affected by recent diet, exercise, or by just-administered antidiabetic drugs. "However, the test is still somewhat expensive and not all clinics have access to a lab with facilities to perform it.
Control of Diabetes
The cornerstone of treatment of diabetes at any age is diet. Dietary counseling of the elderly requires equal consideration of the social and financial aspects of meal planning, as well as to the food itself. The social aspects of meal planning should consider these questions:
* Does the diabetic prepare his/ her own meals or are they prepared for a large group through a community agency or a boarding home?
* Does the diabetic have the knowledge and facilities for nutritious and varied meal preparation?
* Does the elderly diabetic do his/ her own grocery shopping or does someone else do it?12
* Is the source of income enough to allow for the proper diet?
A nutritional history is very important and will describe meal patterns and food preferences. Diet plans can be adapted to each individual based on that person's particular lifestyle. A dietician is a most valuable asset for a clinic and is the most qualified individual for planning meals. Unfortunately, many smaller clinics do not have this resource so the nurse must function in this role. Needless to say, principles of nutrition need to be relearned if the nurse is to function adequately in this aspect of care.
Additional problems to consider in diet planning are the elderly person's state of dentition and any other necessary dietary restrictions - low sodium or cholesterol, low protein, lactose intolerance, food allergies, etc.13
The majority of elderly diabetics, the Type II or non-insulin dependent, usually are obese to some degree. Obesity here can be defined as approximately 20% overweight according to weight, height, frame size, and muscle mass. In Type II diabetes, there is usually a sufficient secretion of insulin but a relative deficit in insulin receptors. Hyperglycemia results because available insulin cannot transport glucose into the cell without a receptor site for binding. Weight loss or maintenance of a weight goal promotes a relative increase in the number of receptor sites, thereby promoting insulin utilization with a subsequent lowering of blood glucose levels.14
In the Type I diabetic, the need for weight maintenance often is more important than the need for weight loss. These diabetics usually aren't obese and have insufficient secretion of insulin. After daily doses of insulin are regulated, weight loss or gain can cause hypoglycémie or hyperglycémie episodes. Preventing hypoglycemia in the elderly is especially important because it can cause cerebral dysfunction that might be easily dismissed as confusion or senility and it can progress to stupor and coma.
Exercise has been a component of diabetes control that has been slighted in recent years. Research indicates that exercise can be a valuable activity in controlling Type II diabetes. Exercise surpresses insulin secretion and increases insulin sensitivity, possibly through increasing the number of insulin receptors.10 All exercise programs must be individualized but the goal should be regular exercise of long duration. All exercise programs are begun lightly and increased as tolerance increases. A walking program is the most practical exercise program for most elderly because it doesn't require a lot of time, can be done nearly anywhere, and costs no money.14 Obviously, not all elderly people, diabetic or not, can participate in walking programs. Cardiovascular and arthritis problems prevent many of the elderly from engaging in a walking program. Additional considerations are da rige ous neighborhoods and the weather. Creativity is a must in these cases. At least one large shopping mall in Memphis allows bypass surgery patients to come in before store hours for postsurgery walking. Senior citizens who live in the high rise in which our universitysponsored clinic is located are advised to walk the hallways of their building, ascending and descending stairs if possible, when the weather is bad. This can be done on a yearround basis. Even bedridden diabetics can exercise - active range of motion several times a day is beneficial. Other plans can be devised to meet the needs of nearly all diabetics.
Insulin Therapy- The same principles of insulin management apply to the elderly as they do to all age groups: site rotation, regularity of meals, consistent injection-meal patterns, drawing up insulin, recognition of symptoms and signs of hypoglycemia.
Caution should be used in initiating insulin therapy in an older individual because of the danger of hypoglycemia. Ideally, insulin therapy should be initiated in a controlled environment such as a hospital.4 However, if the older diabetic demonstrates the capacity to closely follow instructions and has a strong family support system, insulin therapy can be started in the clinic with close follow-up until control is achieved.
Two immediate problems of many elderly diabetics that create difficulty with insulin use are 1) visual deficits that prohibit drawing up insulin accurately and 2) joint disorders, such as arthritis, that inhibit the manipulation required in withdrawing and injecting insulin.
If the patient has a support person, these factors should not pose a problem. If no support person is available, other avenues of approach must be explored. The most logical resource would be a referral for a home health nurse to prefill syringes and assess the person periodically. There occasionally will be an older diabetic who cannot draw up insulin and is, for some social or financial reason, ineligible for home nursing. It should not be unreasonable to allow this person free clinic visits when nothing more is needed than prefilling syringes.
Sulfonylureas- Many Type II diabetics are overweight but often can be managed by diet alone if sufficient weight loss occurs. Those who require more help, but don't require insulin, usually are started on the sulfonylureas, which are a class of oral hypoglycemia drugs.
The sulfonylureas are popular oral antidiabetic drugs. As a class, their mechanism of action remains unclear and their therapeutic usefulness is somewhat controversial. There are four drugs in this class: tolbutamide, chlorpropamide, tolazamide, and acetohexamide. The University Group Diabetes Program in 1970 suggested that tolbutamide is no more effective than diet alone. The sulfonylureas seem to work by increasing the responsiveness of the plasma cell membrane, possibly by increasing the number of insulin receptors.15 These drugs are excreted through the renal system. Some implications for the older diabetic on these drugs follow:
1. Weight loss and the sulfonyureas both seem to increase the number of insulin receptors; however, loss of weight may cause only a relative increase. The sulfonylureas probably have their place in the management of diabetes but should be used as a supplement to dietary management and weight loss. Nurses and patients become complacent with diabetic management through these drugs when the principle method of control should be slow, steady weight loss and weight control.
2. These drugs can accumulate in the body and can cause significant hypoglycemia. Accumulation occurs because they are excreted renally and the glomerular filtration rate often is reduced in the elderly. Ideally, weight loss would allow these drugs to be discontinued.
One last factor to consider with these drugs is the potential for interaction with other drugs. The average elderly person is taking 5.6 drugs daily. The addition of the sulfonylureas to the regimen increases the potential for harmful interactions.
Controlling diabetes in any age group is not an easy task. In the elderly, it becomes even more difficult due to physiologic changes and the social and/or financial hardships faced by many of the elderly. We must remember that each patient is an individual and will have a different set of circumstances related to the control of his/her disease. To be successful in dealing with these circumstances requires patience and persistence; listening, teaching, and communication skills; and knowledge of diabetic pathophysiology, aging changes, and nutrition. Here are some important points to remember:
1. Laboratory tests must be adjusted for age and not evaluated according to standards. Some texts give normal laboratory values for various tests in the elderly.
2. The presentation of diabetes in the elderly is often atypical.
3. Socioeconomic conditions may prevent many elderly people from complying with therapy in an ideal manner.
- 1. West KM: Epidemiology of Diabetes and Its Vascular Lesions. New York, Elsevier North-Holland, Inc, 1978, p 212.
- 2. Kart CS, Metress ES, Metress JS: Aging and Health: Biologic and Social Perspectives. Menlo Park, CA, Addison Wesley Publishing Co, Inc, 1978, p 163.
- 3. Dudley JD: The diabetes educator's role in teaching the diabetic patient. Diabetes Care 1980; 3(1):127-133.
- 4. O'Hara-Devereaux M, Andnis LH, Scott CD: Eldercare; A Practical Guide to Clinical Geriatrics. New York, Gruñe and Stratton, Inc. 1981, pp 142, 146.
- 5. Zummerman D: Neuropathies of diabetes: Part 1: Symmetric neuropothy. Minnesota Medicine 1980; 63(2): 119124.
- 6. Isselbacher JJ, Adams RD, Braunuald E, et al: Harrison 's Principles of Internal Medicine, ed 9. New York, McGraw-Hill Book Co, 1980, p 1755.
- 7. O'Brien MT, Pallett PJ: Total Care of the Stroke Patient. Boston, Little, Brown and Co, 1978, p 2.
- 8. Walesky ME: Diabetic ketoasidosis. Am J Nurs 1978; 78(5):874.
- 9. Porte D, Graf RJ, Halter JB, et al: Theories of pathogenesis of diffuse polyneuropathy. Am J Med 1981; 70(1):195200.
- 10. RunyanJW: Problem Oriented Primary Care, ed 2. Philadelphia, Harper and Row, 1982, pp 245, 105-107.
- 11. Clements RS, Keane NA, Kirk KA1 etal: Comparison of various methods for rapid glucose estimation. Diabetes Care 1981;4(3):392-403.
- 12. Dickelmann N: Primary Health Care of the Well Adult. New York, McGrawHill, Ine, 1977, pp 179-185.
- 13. Blevins DR: The Diabetic and Nursing Care. New York, McGraw-Hill, Ine, 1979, p 342.
- 14. Bonar JR: Diabetes: A Clinical Guide. New York, Medical Examination Publishing Co, Inc, 1980, pp 87-89, 263-264.
- 15. Lebovitz HE, Feinglas MN: Sulfonylurea drugs: Mechanism of anti-diabetic action and therapeutic usefulness. Diabetic Care 1978; 3(1):189-198.
SIQNS-SYMPTOMS INDICATING POSSIBLE DIABETES IN THE ELDERLY