Older drugs designed to treat mental problems such as delirium, agitation and psychosis may be even more hazardous to the elderly than newer medicines that carry U.S. government warnings, a study showed on Wednesday.
The Food and Drug Administration warned in April that newer "atypical" anti-psychotic medicines such as Johnson & Johnson's Risperdal and Eli Lilly & Co.'s Zyprexa nearly doubled the risk of death in elderly people with dementia.
The study said those warnings should have been extended to older drugs such Haldol and Thorazine, available in generic form, because they posed a risk of death that was 37 percent higher than the atypical drugs.
The report in The New England Journal of Medicine also illustrated the risks of taking studies involving mostly younger people and trying to apply those findings directly to the elderly who may react differently to drugs.
Elderly people are more likely to be given antipsychotic drugs than people in other age groups. They are prescribed for more than 1 in 4 nursing home patients covered by Medicare.
Nonetheless, there is surprisingly little data on how they work in people 65 and older, said Philip Wang of Brigham and Women's Hospital in Boston, the chief author of the study.
"We don't know what the benefits are, or what the optimal treatment for them is. But the risks are starting to emerge," he told Reuters.
He and his colleagues found that among the people taking the newer drugs, 14.6 percent were dead within the first 180 days. The rate was 17.9 percent for those who began taking the older antipsychotics between 1994 and 2003.
The greatest danger appeared to come when the patients were first taking the medicine and among people receiving the highest doses.
"These results suggest that clinicians should not simply take the atypical agents they stopped prescribing in response to the FDA warning and replace them with the older drugs," said Wang. "This is not an inconsequential risk. The elevation in the death rate we're seeing is over a very short period of time."
The Wang team used a database of 22,890 seniors who had drug insurance benefits in Pennsylvania.