Older Antipsychotic Drugs No Safer Than New Ones
Researchers warn about replacing the newer meds that carry warnings
WEDNESDAY, Nov. 30, 2005 (HealthDay News) -- Older antipsychotic medications appear to be no safer than newer antipsychotic drugs in elderly people, and should not be used to replace the newer drugs without careful consideration.
That's the conclusion of a study appearing in the Dec. 1 issue of the New England Journal of Medicine.
The issue of replacing one generation of drugs for another has become a concern since April of 2005, when the U.S. Food and Drug Administration started requiring that newer antipsychotic drugs carry a "black-box" warning. The warning states that these medications nearly doubled the risk of death among older patients compared with a placebo.
Older drugs do not carry such a warning -- but probably only because the FDA didn't have the necessary data, pointed out lead researcher Dr. Philip Wang, a psychiatrist and epidemiologist at Brigham and Women's Hospital and an assistant professor of psychiatry, medicine and health-care policy at Harvard Medical School, both in Boston.
Some experts have worried that clinicians are interpreting the absence of data as an absence of risk and are prescribing older drugs because they think they are safer.
"If they're switching because they think there's no risk because the FDA didn't include older drugs in the advisory, then that's not a good switch," Wang said. "If they're going to switch, they should do so fully informed."
"The older drugs have at least a comparable risk and may be higher, but they don't have a black-box warning," he added.
In this study, Wang and his colleagues set out to define the short-term risk of death among elderly patients taking the older or conventional antipsychotic medications. The older medications included Thorazine and Haldol, while the newer or second generation drugs included Abilify and Clozaril.
The researchers looked at nearly 23,000 patients aged 65 or older who had drug insurance benefits in Pennsylvania and who began taking antipsychotic medications between 1994 and 2003.
Individuals who were prescribed the older drugs had a 37 percent higher risk of death than those prescribed the newer medications.
In the first 180 days of use, 17.9 percent of patients on conventional antipsychotic medications died vs. 14.6 percent of those taking the newer agents.
The greatest increase in risk of death for users of conventional antipsychotic drugs was in the first 40 days after starting therapy. Here the risk was 56 percent higher.
Antipsychotic medications are widely used in the elderly population for a variety of conditions including dementia, delirium, psychosis and agitation. More than a quarter of Medicare beneficiaries in nursing homes have such prescriptions, the researchers noted.
At the same time, many drugs that are widely used for elderly patients have not been well studied in that population.
"Very often the information on the benefits and the risks of drugs in the elderly is just taken from trials of younger adults," Wang said. "The elderly are just more vulnerable, and clearly there's a susceptibility to these medications that was never picked up in trials."
The study sheds no light on what are the best medications to prescribe, only on what issues need to be kept in mind, Wang said.
"Clinicians are in a tough spot," the Harvard expert said. "They have to be very cautious and thoughtful and do a good job of balancing of what they think the benefits will be against the risks. If they approach this as if there were no risk to the drugs, that's problematic."
For more on the recent black box warning on antipsychotics, go to the U.S. Food and Drug Administration.