Diabetes as You Age

The likelihood of developing diabetes increases as you get older. Almost 20 percent of people older than sixty-five have diabetes, and this number increases to almost 40 percent of people over age eighty. This is partly because people with diabetes are living longer and also because aging is associated with decreases in insulin secre­tion from the pancreas. With people living longer, diabetes is therefore a major health issue in old age. The majority of elderly people with diabetes have type 2 diabetes, but type 1 diabetes can also occur.

There are a number of issues that need to be considered when discussing diabetes in the elderly population:

• Blood glucose targets.
• How physical changes that occur with aging will affect diabetes management.
• How diabetes will impact other diseases of aging.
• Treatment of diabetes complications and associated disorders (for example, blood pressure and lipid levels)
• How drug interactions will affect the treatment of diabetes and other diseases.

Blood Glucose Targets in the Elderly
When you think about glucose targets in elderly people with diabetes, it is helpful to separate those elderly people who developed diabetes when they were younger from people who develop the disease in old age.

If you were young when you developed diabetes, you have already established targets for glucose control, and it may not be necessary to change them as you age. However, if you have complications from diabetes, your targets may need to be changed to reflect your current disease state.

When setting blood glucose targets for elderly people, doctors take into consideration the life expectancy of the individual, because this will affect how the diabetes is managed.

The average life expectancy for a sixty-five-year-old woman in the United States is nineteen years, and for a man, it is fifteen years. At age seventy-five, the life expectancy is twelve and nine years respectively. Thus, after age seventy-five, what matters more is glycemic control to prevent short-term complications and not neces­sarily long-term complications. So, if you are forty-five and had poor glucose control, your lifetime risk of becoming blind is high, whereas if you are seventy-five and had the same glucose level, your likelihood of going blind due to diabetes is only 0.5 percent. In other words, there is a change in the risk-benefit analysis equation.

Even though there may be less concern about long-term complications, good glu­cose control is still important to prevent infections such as urinary tract infections and yeast infections. Glucose control will also impact your general nutritional state and your sense of well-being. The American Geriatrics Society recommends an HbA1c goal of less than 8 percent in frail individuals (frail meaning people who do not have much physical reserve and become ill easily) with a life expectancy of less than five years, or when risks of intensive glycemic control outweigh benefi ts. For healthy people over seventy-five, the HbA1c target of less than 7 percent is the same as in younger individuals. Your age, your health status, and your motivation to con­trol your diabetes are all taken into account when your doctor is setting blood glu­cose targets for you.

Aging Affects Diabetes Management

Physical changes that occur as the body ages will affect the management of diabetes as follows

METABOLISM OF MEDICATIONS

As you get older, your kidney function declines, so the effects of many oral diabetes medications and insulin last longer. Therefore, your doctor will avoid (or use more cautiously) the long-acting sulfonylureas such as glyburide and glimepiride that are more likely to result in low glucose reactions. Instead, he or she will use the fast-acting sulfonylureas (glipizide or tolbutamide), or nateglinide or repaglinide. How­ever, this makes more frequent dosing necessary, and this may make it harder to remember to take your medications. Kidney function can also decline when an elderly person is ill and becomes dehydrated (for example with pneumonia). If this happens and the person is taking metformin for diabetes, the amount of metformin in the bloodstream can go up and cause a serious condition called lactic acidosis. For this reason your doctor will most likely prescribe lower doses of metformin and do blood tests to monitor your kidney function, especially when you are ill.

HEART DISEASE

Elderly patients are more likely to have had a heart attack or have heart disease due to high blood pressure. They are more prone to develop heart failure, and so doctors will avoid (or use cautiously) medicines such as rosiglitazone or pioglitazone that can precipitate heart failure.

If an older patient has angina, hypoglycemia is more dangerous because it can precipitate an angina attack. Therefore, doctors are cautious in using insulin and oral medications that cause hypoglycemia in people with angina.

MALNOURISHMENT

When an elderly person is acutely ill, the loss of appetite can deplete the liver gly­cogen stores, and this increases the risk of hypoglycemia, especially at night. If an elderly person has dementia or has had a stroke, swallowing can become impaired, and this too can increase the risk of hypoglycemia. Under these circumstances, the diabetes medicines tolbutamide, nateglinide, and repaglinide can be given before each meal, and if the person is not eating, the dose can be skipped.

NEUROLOGICAL CHANGES

Elderly people may not have as many symptoms in response to hypoglycemia (tremor, sweating, fast heart rate, hunger), and so they may not recognize low glu­cose reactions as well as younger individuals do. This can cause a delay in treat­ment, and glucose levels can go dangerously low. If an elderly person is delirious because of an acute illness or is chronically confused because of dementia, his or her caregivers may have difficulty recognizing and treating low glucose reactions.

The perception of thirst is often altered in older people, and if they do not drink enough, they can become dehydrated and have elevated glucose levels. This is espe­cially a problem when the person is immobile and does not have ready access to water.

Memory changes in the elderly can impact their ability to manage diabetes. For example, they may not remember to take the medications. They may not be able to draw up or adjust the insulin doses for the food eaten. When this happens, caregiv­ers may need to remind them to take their medications and supervise the insulin injections.

MOBILITY

Elderly people who have difficulty walking may have problems getting to the kitchen to treat their low glucose levels, so they should keep fast-acting carbohydrates such as glucose tablets close by.

Exercise remains important in elderly people with diabetes—it may reduce the person’s need for additional medicines to control the glucose levels, and he or she is less likely to fall down.

VISION

As a person ages, his or her vision may deteriorate because of cataracts or macular disease, and it may be harder to monitor glucose levels. Using a magnifying glass when drawing up insulin, or better still, using insulin pens to dose the insulin, may make things easier.

ARTHRITIS

Osteoarthritis and rheumatoid arthritis of the hands can make it harder to open bot­tles of medicines, to draw up insulin, or to use pens. Novo Nordisk makes a dispos­able, prefilled Novolin InnoLet insulin doser, which has a large, easy-to-read dial, with audible clicks, to make it easier to select and inject the correct dose of insulin.

Elderly people with long-standing diabetes are more likely to have kidney disease, nerve damage, and circulation problems such as heart disease and stroke. They are less able to walk, do housework, prepare meals, and manage money when compared to age-matched individuals who do not have diabetes. Women with diabetes become disabled at approximately twice the rate of women without diabetes, and they have an increased risk of falls and hip fractures. Long-standing diabetes can affect bone quality, and diabetes increases the risk of fractures with falls.

Neurological deterioration is greater in people with diabetes: they are more likely to develop memory problems and have more rapid deterioration in memory with time. Part of the reason for the more severe deterioration in cognitive function may be the effect of diabetes on the blood vessels and increased risk of small strokes.

Institutional Aspects of Diabetes
Elderly people living in board and care and nursing facilities may have additional challenges regarding their diabetes management. They may have to rely on caregiv­ers to check their glucose levels and administer their diabetes medications. They may not have control over their meals. The staff may have limited understanding of diabetes management—because type 2 diabetes is so much more common, people tend not to remember that older individuals can have type 1 diabetes. These type 1 patients may not get adequate insulin bolus for their meals. Due to limited supervi­sion, sophisticated insulin basal-bolus regimens may not be realistic, and some level of control may have to be sacrificed for safety. In these situations, insulin injections once or twice a day may have to suffice.

Treatment of Diabetes Complications and Associated Disorders

Diabetes complications in elderly people are treated in the same ways as in younger individuals. Treating the lipid abnormalities and blood pressure is equally beneficial in the elderly as in younger individuals. In fact, because the risk for heart attack and stroke is higher in the elderly, benefits may actually be greater than in the younger population. The blood pressure target is less than 140/80 if tol­erated. ACE inhibitors and angiotensin receptor blockers (ARBs) can be used to lower blood pressure, but these medicines can raise the potassium and serum creati­nine levels. High potassium levels can be dangerous and affect the heart rhythm.

Often, elderly people are on many different medications because they are being treated for other medical problems as well. In these situations, you need to watch out for drug interactions between medications, because they will affect your well­being. For example, if you are taking glipizide for your diabetes, taking an antibi­otic called ciprofloxacin can sometimes cause low glucose reactions.

Prednisone, a steroid that is given for bronchitis and rheumatological conditions such as acute gout, polymyalgia rheumatica, and other inflammatory conditions, can cause glucose levels to go high, and adjustments in your  diabetes medications may be necessary.

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