Reliable? Heart studies often exclude the elderly

NEW YORK (Reuters Health) - The vast majority of heart failure cases occur in adults aged 65 and older, but a report out today found that a large number of clinical trials studying the disease exclude older patients, often unnecessarily.

That means most of the treatments being developed for the condition have not been tested on the patient population who will be taking the drugs.

"It has been more than twenty years since regulatory agencies have been trying to include more older people in clinical trials, but the situation doesn't seem to be changing much," Dr. Antonio Cherubini, a geriatrician at the University of Perugia Medical School in Italy, told Reuters Health.

Heart failure affects more than five million Americans, according to the National Institutes of Health. The condition occurs when the heart has difficulty pumping blood throughout the body and symptoms include fatigue and shortness of breath.

Forty-three percent of the 251 heart failure trials analyzed by Cherubini and his collaborators excluded the elderly without proper justification, the authors conclude in the Archives of Internal Medicine.

A quarter of the evaluated studies excluded older patients based on age alone, a practice that the American Geriatrics Society and other groups have been working to phase out for years. Other trials excluded the elderly indirectly by rejecting patients who have multiple diseases or take multiple medications.

For example, about 20 percent of the studies excluded patients already taking more than one drug, which would rule out more than 75 percent of Americans over the age of 60, according to a recent report by the Centers for Disease Control and Prevention.

Leaving older patients out of clinical trials can have serious implications. Several studies have shown that taking multiple medications and suffering from other disorders--the very criteria that get the elderly excluded from clinical studies--can affect disease symptoms and drug response.

"Older patients are not the same as younger patients," said Dr. Nicola Hanania, a lung specialist at Baylor College of Medicine in Houston, who specializes in asthma, another disease that experts say is understudied in older adults.

"We're not really doing these patients any favors by not looking at these issues," Hanania, who was not involved in the new study, told Reuters Health. "I hate to say the word ignored, but that's really what it is."

The need for more clinical study of older patients will only grow as life expectancy increases. The US Census Bureau has projected that, by 2030, the number of Americans over 65 will double and the population over 85 will quadruple.

"The elderly are difficult to include in clinical trials because they have so many ongoing problems," said Cherubini. "That's why we need specific trials that are designed for older subjects. The science needs to adapt to them."

SOURCE: bit.ly/7qXyI Archives of Internal Medicine, online March 28, 2011.