Antibiotic Use, Costs Show Wide Regional Variations

"Changes in prescribing behavior of healthcare providers for sinusitis are urgently needed to improve healthcare quality and stem the rising tide of antibiotic resistance in the United States," they wrote.

Zhang says that in addition to unnecessarily raising the costs of care, inappropriate use of antibiotics, for example, to treat symptoms of a cold or a respiratory tract infection caused by a virus, give way to the emergence of resistant strains of bacteria.

"We know from previous studies that the rate of resistant strains in the south, especially, is higher than anywhere else in the country," she says.

Zhang explains that severity or type of illness does not account for the variation because adjustments were made for age, gender, race, poverty, and health status or condition.

"It may be patient or physician preference. Some patients may prefer to use antibiotics even if they're told by their doctors that they're not effective, and some physicians may just be more likely to prescribe antibiotics," even if the patient doesn't have a bacterial infection.