The cost of antibiotics in treating upper respiratory tract infections in a medicaid population.

OBJECTIVE

To examine the use and cost of the nonindicated treatment regimens of antibiotics for nonspecific upper respiratory tract infections (URIs) in a Medicaid population.

DESIGN

A cross-sectional sample of Kentucky Medicaid claims for 50000 people (July 1, 1993-June 30, 1994).

SETTING

Episodes of care were created linking outpatient and emergency department visits for URIs to medications filled within a 5-day period.

PARTICIPANTS

Individuals who were seen in ambulatory care for a URI as defined by the International Classification of Diseases, Ninth Revision, Clinical Modification codes 460 and 465. Of the 15706 episodes, 95% were outpatient office episodes. The outpatient episodes were accounted for by 8784 patients and 946 physicians.

MAIN OUTCOME MEASURES

Use of antibiotics in URI episodes. Proportionate costs and costs per episode were computed based on claims paid by Medicaid.

RESULTS

Sixty percent of outpatient episodes and 48% of emergency department episodes resulted in an antibiotic prescription being filled. In outpatient settings, episodes in which secondary diagnoses of either otitis media or acute sinusitis were found accounted for less than 6% of the episodes that resulted in an antibiotic prescription being filled. The most frequently filled antibiotic was amoxicillin, although second- and third-generation cephalosporins were the second most frequently occurring antibiotic class. Twenty-three percent and 9% of outpatient and emergency department episodes, respectively, resulted in a prescription filled for antihistamines. In outpatient episodes, antibiotics account for 23% of the total cost of care. In emergency department visits, antibiotics account for 8% of the cost of URIs. Antibiotics cost, on average, $9.91 for each episode of care in outpatient office visits. An estimate of the cost of antibiotics for URIs in a year for the Kentucky Medicaid program is $1.62 million.

CONCLUSIONS

The results indicate that a substantial proportion of resources in Medicaid are being used for nonindicated and ineffective treatments for URIs. With the increase in antibiotic-resistant pathogens and shrinking public health care funding, the current treatment for URIs should be reexamined.