Trends in antimicrobial drug prescribing among office-based physicians in the United States.

To assess changes in oral antimicrobial drug prescribing by office-based physicians from 1980 through 1992, with emphasis on the treatment of otitis media and sinusitis and on the possible impact of demographic variables on such use. The National Ambulatory Medical Care Survey is a sample survey of office-based physicians in the United States conducted by the National Center for Health Statistics, Centers for Disease Control and Prevention. Physicians' offices. Physicians sampled for the 1980, 1985, 1989, and 1992 National Ambulatory Medical Care Surveys, which included groups of 2959, 5032, 2540, and 3000 physicians, respectively. Sample physicians responding in 1980, 1985, 1989, and 1992 reported data for 46,081, 71,594, 38,384, and 34,606 sample office visits, respectively, including information on antimicrobial drug prescribing. Trends in the antimicrobial drug prescription rates. From 1980 through 1992, increasing prescribing measured by the annual drug prescription rate per 1000 population, was found for the more expensive, broad-spectrum antimicrobial drugs, such as the cephalosporins; decreasing rates were observed for less expensive antimicrobial drugs with a narrower spectrum, such as the penicillins. No trend was found for trimethoprim-sulfamethoxazole, the erythromycins, or the tetracyclines. During the decade, an increasing trend in the visit rate to office-based physicians for otitis media was observed, while the visit rate for sinusitis among adults was found to be higher in 1992 than in each of the other study years. The increased use of broader-spectrum and more expensive antimicrobial drugs have implications for all patients because of the impact on health care costs and the potential for the emergence of antimicrobial resistance. The data suggest that the incidence of otitis media and sinusitis is increasing.