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NOVEMBER / DECEMBER 2003

AROUND HARVARD

This article originally appeared in the September 2003 Harvard Heart Letter and is provided courtesy of Harvard Health Publications.

Anemia: Beyond iron-poor blood

This often overlooked condition can affect the heart and health. Getting more iron doesn’t always help.

If you’re of a certain age, you may remember commercials on the old Ted Mack Amateur Hour telling you how Geritol could put the pep back in “iron-poor blood.”

The claims were questionable. But the problem they hinted at isn’t. Anemia affects about one in eight older Americans, or about 5 million people. This problem doesn’t necessarily have to do with iron. Anemia means having too few oxygen-carrying red blood cells in circulation. This can stress virtually every system in the body.

Doctors have long tended to look at anemia as a kind of innocent bystander, accepting it as a consequence of aging or some chronic diseases. It’s much more than that. Anemia in itself is bad for the heart because it makes the entire cardiovascular system work harder. And now there’s a growing realization that anemia may contribute to heart disease or amplify its symptoms, especially in heart failure. There’s also intriguing preliminary work that treating anemia may ease heart failure symptoms and improve heart function.

Arriving at anemia
At this very moment, deep in the marrow of your bones, billions of immature stem cells are being transformed into new red blood cells. As these disc-shaped cells mature, they pack themselves with hemoglobin, the protein that grabs oxygen from the lungs and releases it to the body’s tissues. After about five days in the bone marrow, the new red cells stream into the blood.

This vital process can hit several roadblocks. Too little iron, vitamin B12, or folic acid can slow the production of red blood cells. So can cancer, some infections, and kidney disease. Anemia can occur even when your bone marrow and diet are healthy if chronic bleeding outpaces the marrow’s ability to make new red blood cells. Common causes of such bleeding include a stomach ulcer, hemorrhoids, chronic use of aspirin or other nonsteroidal anti-inflammatory drugs, or polyps or tumors in the digestive or urinary system.

Mild anemia often doesn’t cause problems. Many people learn they have it from a blood test. Others develop symptoms that are classic signs of anemia but often aren’t attributed to the condition because they tend to come on slyly. Sometimes they are chalked up to old age or other conditions. The most common symptoms include:

  weakness or fatigue
  fast or troubled breathing
  rapid heartbeat or palpitations
  headaches
  dizziness
  sensitivity to cold.

Trouble in the heart
A handful of studies has shown that in people with heart failure, anemia adds insult to injury. Careful work from medical centers in the United States, Canada, and England shows that up to half of people with heart failure are anemic. The combination is linked with more severe symptoms and poorer daily function, and people with heart failure who also have anemia don’t seem to live as long as those without anemia.

Whether anemia causes these problems or is just another result of heart failure is still up in the air. One way researchers hope to answer this question is by seeing if treating anemia can ease the symptoms of heart failure. Two early studies suggest it can. Both used the drug erythropoietin (Epogen, Procrit), a hormone that stimulates bone marrow to make red blood cells. In an Israeli study, treating anemia improved heart function, eased symptoms, and reduced the need for some medications. Researchers at Columbia University in New York showed that erythropoietin treatment improved both the ability to exercise and quality of life.

Because these studies were small and lasted for just a few weeks, they can only hint at the possible benefits of erythropoietin therapy, which is fairly expensive. Longer, larger studies should yield clearer answers.

Types of anemia
Before you rush out to buy iron pills, you need to know that there are dozens of types of anemia, some of which have nothing to do with iron. You don’t want to take iron if you don’t need it. Too much iron can keep your body from absorbing calcium and zinc, and some research suggests it may increase the risk of heart disease, cancer, and diabetes. The two types of anemia most likely to be a problem in older adults are iron-deficiency anemia and anemia of chronic disease.

Iron-deficiency anemia: If your diet is low in iron, if your body can’t absorb the iron you eat, or if you lose iron through bleeding, you’ll develop iron-deficiency anemia. The first thing you and your doctor must do is determine what’s causing it. Treatment then focuses on correcting the underlying problem and replenishing your iron stores with food or iron pills.

Anemia of chronic disease: Cancer, chronic infections, arthritis, heart failure, and a host of other diseases interfere with the body’s ability to use stored iron. It’s like starvation in a land of plenty — surrounded by iron-rich cells, developing red blood cells perish for lack of iron. Iron pills can’t fix this. Only treatments that stimulate red blood cell production, such as erythropoietin, can help.

Check your red cells
Although many people develop anemia as they get older, it isn’t an inevitable consequence of aging. Instead, it’s more a function of chronic health problems or a poor diet.

Since anemia is relatively common among older people, it makes sense to be tested for it every few years. This may be especially important if you have heart failure. A routine test called a complete blood count, or CBC, includes such measures as hematocrit (the percentage of your blood taken up by red blood cells) and hemoglobin level.

If you need more iron...
Food is the best way to boost your iron intake because it’s easier for the body to absorb iron from food than from pills. Meat and fish are good sources of iron, as are leafy green vegetables, beans, dried fruits, prune juice, nuts, and whole grains. Cooking in a cast-iron skillet or iron pot can also help. Vitamin C boosts the amount of iron you absorb, so try to include foods rich in vitamin C with a meal, or have an orange or some cantaloupe afterward. Coffee, tea, and milk can bind with iron and make it harder to absorb, so try not to drink these with a meal.

If your doctor suggests that you take an iron supplement, a standard generic pill is cheaper and just as effective as a brand name. The most easily absorbed type of iron is ferrous sulfate. If this kind upsets your stomach, try another. Taking iron pills with meals can prevent stomach problems. Eating enough fiber and drinking extra water can prevent constipation.