NEW YORK (Reuters Health) - More seniors used antibiotics after enrolling in Medicare Part D, the program that helps pay for prescription drugs, in a new study of about 35,000 people.
The results are promising for conditions like pneumonia, which is sometimes deadly in the elderly but can be effectively treated with antibiotics, the authors say. But study participants with viruses also took more antibiotics - which don’t do anything against those types of infections.
Unnecessary use of antibiotics contributes to resistance - when bacteria build up immunity to these drugs and the drugs are no longer effective.
“Antibiotics are a unique class of medications; overuse can harm entire populations of patients ... whereas underuse may result in serious complications of infections,” wrote Dr. Adam Hersh and Dr. Ralph Gonzales of the University of California, San Francisco, in a commentary on the article, which is published in Archives of Internal Medicine.
Led by Dr. Yuting Zhang at the University of Pittsburgh, the researchers followed seniors who enrolled in Medicare Part D when the program was implemented in January 2006. Some of the patients had no drug coverage before enrolling in Part D - they paid for all of their prescription medications out-of-pocket. Other patients had limited coverage that paid for some of their medications.
The authors tracked how many patients filled prescriptions for antibiotics in the two years before they enrolled in Part D and in the two years after to see if the program changed their drug use. As a comparison, they used a group of seniors who stayed on the same private insurance for all four years.
Participants who had no or limited drug coverage before enrolling in Part D were more likely to use antibiotics after enrolling. The biggest difference was among people who had no drug coverage until Part D: in the two years before enrolling, 34 percent of them used antibiotics, compared to 41 percent afterwards.
People who remained on private insurance were slightly less likely to use antibiotics in the second half of the study than in the first half.
When the researchers looked at specific conditions, they found that after part D, seniors were more likely to get antibiotics when they saw a doctor for pneumonia. Before Part D, 28 percent of those pneumonia patients who didn’t have drug coverage filled a prescription for antibiotics, while 47 percent did so once they had Medicare benefits.
That’s good, the authors say - it shows more people are getting the treatment that they need. Every year, up to 600,000 elderly Americans are hospitalized for pneumonia.
But people who saw a doctor for conditions like the common cold and acute bronchitis also took more antibiotics than they did before Part D was implemented. These conditions are generally caused by viruses, not bacteria, and so won’t improve with antibiotic treatment.
The more antibiotics that are used - when they’re needed and when they’re not needed - the more likely bacteria are to become resistant to the drugs. Resistant infections can then spread so that more and more people have conditions that no longer respond to certain antibiotics. Resistant cases are often more dangerous and more expensive to treat.
In many cases, Zhang told Reuters Health, “patients didn’t know that by taking those drugs, sometimes they won’t be helpful.”
The authors found the biggest increases in use among the newest, most expensive drugs - the ones that public health experts are most worried about saving for the worst infections.
“People without drug coverage may have been using those cheaper generics whenever possible, but now that they have coverage they are availing themselves of what may be perceived as a ‘better’ antibiotic because it is more costly,” Dr. Susan Foster, the director of public policy and education at the Alliance for the Prudent Use of Antibiotics (APUA) in Boston told Reuters Health in an email. The reporter worked briefly at APUA earlier this year.
While doctors are aware of the dangers of antibiotic resistance, Zhang said, “in some cases they don’t really know if it’s virus or bacteria.” And sometimes, she said, patients come in wanting antibiotics so doctors will give them a prescription.
Another new study, led by Dr. Christopher Millett of the Imperial College Faculty of Medicine in London and also published in Archives of Internal Medicine, found that patients without prior drug coverage spent about half as much out-of-pocket for prescription medications after enrolling in Medicare Part D.
The program costs the U.S. government about $1,500 a year for each person enrolled - about 32 million, as of 2008.
Zhang, who receives some funding from health insurer Highmark Inc., thinks that one way of keeping doctors from prescribing unnecessary antibiotics - which would save money and prevent resistance - is to change how they are compensated by the government. For example, prices could be increased for drugs when they’re prescribed for conditions they aren’t supposed to treat, she said, or restrictions could be put on using the most expensive antibiotics so they are saved for the sickest patients.
More education, for both doctors and patients, is needed as well, Foster said. “Clearly there is still a lot to do to educate patients about what antibiotics can and cannot do, and to help providers to communicate effectively with their patients, especially when antibiotics are not clearly indicated,” she said.