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.
If you are taking nitrate
medicines for heart disease, you cannot use the phosphodiesterase inhibitors (sildenafi l, vardenafil, or
tadalafil) for erectile dysfunction.
|