Older people living in the South tend to use more antibiotics than their counterparts living elsewhere in the United States, a new study shows.
These high rates are not tied to any differences in disease patterns, researchers found, suggesting that antibiotics may, in fact, be overprescribed in Southern states. Antibiotics overuse is linked to risk of drug resistance, and the proliferation of so-called superbugs.
According to the new study, about 21 percent of people in the South used an antibiotic each quarter of the year. By contrast, the lowest rates of antibiotic use were seen in the West, where roughly 17 percent of people used an antibiotic each quarter. Rates in the Midwest were about 19 percent.
The study, which appears online in the Sept. 24 issue of the Archives of Internal Medicine, found wide variations among antibiotic prescribing rates across geographic regions in the United States. In general, antibiotic prescription rates peak from January through March and dip from July through September, the study showed.
"There are substantial variations across the country for unexplained reasons," said study author Dr. Yuting Zhang, an assistant professor at the University of Pittsburgh. Some states, such as Oregon and Wyoming, do well in terms of keeping antibiotic prescription rates appropriate, she said, and other states could follow their lead with similar programs and policies.
"Patients and providers should know that there is this problem in the South and take some efforts to reduce antibiotic overuse," Zhang added. The variation doesn't stem from differences in the population or illness patterns such as higher rates of pneumonia, however. Some of the areas with the highest uses of antibiotics actually had the lowest rates of pneumonia.
Researchers analyzed Medicare Part D data from 2007 through 2009 -- representing about 1 million patients for each of the three years -- to see how antibiotic prescriptions fluctuated among the U.S. South, Midwest, Northeast, and West in adults aged 65 and over in more than 300 hospital-referral regions.
Older people may be at greater risk for complications from infections, the researchers noted, which suggests that doctors may treat them more aggressively with antibiotics. But seniors also may be more prone to some of the side effects associated with antibiotic use, they added, and doctors should be extra careful when prescribing antibiotics to seniors.
Everyone can do their share to reduce unnecessary antibiotic prescriptions and their consequences, said Dr. Len Horovitz, an internist at Lenox Hill Hospital, in New York City. "Viruses aren't treated with an antibiotic, but bacterial illnesses such as urinary tract infection, strep throat, and pneumonia are."
Don't ask for an antibiotic to nip something in the bud, he advised. Instead, "insist on a culture whenever possible," he said. "There are many things we can do to treat an illness short of prescribing needless antibiotics."
Rest, plenty of fluids, and pain- or fever-reducing medications can help treat many illnesses not caused by bacteria, Horovitz said.
Learn more about antibiotic resistance at the U.S. Centers for Disease Control and Prevention website.
SOURCES: Yuting Zhang, Ph.D., assistant professor, University of Pittsburgh; Len Horovitz, M.D., internist, Lenox Hill Hospital, New York City; Sept. 24, 2012, Archives of Internal Medicine, online