Elders with anemia face increased health risks

June 15, 2006

GAINESVILLE, Fla. — Elderly patients who develop anemia risk serious health problems that increase the odds they will be hospitalized and nearly double the chance they will die, according to findings from a long-term study by a multi-institute research team.

Anemia, a reduction in the oxygen-carrying capacity of the blood that can cause fatigue, weakness and dizziness, is common in old age. But its signs are often subtle, and doctors need to be sure they carefully consider it as they evaluate older patients, say study authors, writing recently in The Journals of Gerontology Series A: Biological Sciences and Medical Sciences.

“Considering anemia should be part of an overall patient’s risk assessment even if the person is without symptoms or apparent clinical disease,” said Marco Pahor, director of the University of Florida’s Institute on Aging and a study’s co-investigator.

The study revealed that even a mild case of anemia increases an elderly person’s risk, indicating that treatment recommendations may need to be adjusted for older patients, Pahor said. Researchers found an association between late-life anemia and heart conditions, cancer, infectious diseases and diabetes.

The World Health Organization defines anemia as a concentration of the oxygen-ferrying molecule hemoglobin that is below 12 grams per deciliter in women, and below 13 grams per deciliter in men.

“Those older patients having mild anemia have not been considered at higher risk, but our data show that even those patients with low or even close to normal range do have higher risk for death and hospitalization and they should be considered for more in-depth screening for other conditions,” Pahor said.

To more fully understand its detrimental health effects, the researchers studied the relationship of anemia to hospitalization and death in 3,607 people aged 71 years or older who participated in the National Institute on Aging-sponsored Established Populations for Epidemiologic Studies of the Elderly. About 13 percent of people 70 or older are anemic, and those percentages increase with age. Most cases occur in association with underlying diseases such as stomach ulcers, chronic infections, cancer, chronic kidney ailments and congestive heart failure or due to malnutrition or iron deficiency. However, up to a third of the time, anemia is not attributable to these factors, so people with pre-existing conditions that could have caused it were excluded from the study.

In the study, 451 participants were anemic. They were more likely to be older black men and women with a lower body mass index. During the four-year follow-up period, 37 percent of those with anemia died, compared with 22 percent of the other study participants. In addition, two-thirds of anemic participants were hospitalized at some point in the study period; only half of those without anemia were.

“We hope this study will promote clinical awareness of anemia as a risk factor for other conditions,” Pahor said. “It is a risk factor for mortality, hospitalization, loss of independence, lower muscle strength and increased inflammation. We would like to do further studies to find out whether, if you could correct anemia, could you prevent these events?”

The first step toward correcting anemia is to, when possible, identify and then treat the underlying disease causing it, Pahor said. Treatment also may involve giving iron when iron levels are low, vitamin supplements to replace folate and vitamin B12 in people with poor eating habits, erythropoietin to increase red blood cell production in people with kidney problems and antibiotics to treat infections.

Dr. Paulo Henrique M. Chaves, an assistant professor of medicine and epidemiology at Johns Hopkins University’s Center on Aging and Health, said the paper provides insight into anemia as a strong prognostic factor for major health complications.

“A little bit of anemia is often perceived as a benign finding in older adults,” Chaves said. “However, results from this study by Penninx, Pahor and colleagues – as well as consistent and recently published findings that link mild anemia and even low-normal hemoglobin levels to a status of increased frailty and greater functional decline in older adults – suggest otherwise, at least in terms of prognostic significance.

“What remains to be established now is whether pharmacological correction of mild anemia in older adults may help slow the disablement process, preventing the onset and progression of frailty and disability, improving quality of life and prolonging survival,” he added. “Randomized clinical trials will be necessary to address these important questions.”

The multicenter team spearheading the current study was a partnership with industry and the federal government. It included researchers from the National Institute on Aging, UF’s Institute on Aging, the Netherlands and Ortho Biotech Products in Bridgewater, N.J., which manufactures Procrit, a hormone that stimulates red blood cell production. Pahor has served as a consultant for the company.