Many cases of heart failure occur in adults aged 65 and older, but a recent report found that several clinical trials examining heart failure excluded older patients, according to Reuters.  This suggests the medications developed for the condition are not tested on the patient population who will be taking the drugs.

"It has been more than 20 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.

Of the 251 heart failure trials analyzed by Cherubini and his collaborators, 43% excluded the elderly without proper justification, the authors concluded in the Archives of Internal Medicine.

A quarter of the studies evaluated excluded older patients because of age alone; others rejected the elderly indirectly by not accepting patients with multiple diseases or those who take multiple medications.

"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 experts say is understudied in older adults.

"We're not really doing these patients any favors by not looking at these issues," said Hanania, who was not involved in the new study. "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 U.S. 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."