Antibiotics and Clostridium difficile diarrhea in the ambulatory care setting.

OBJECTIVE: The goal of this study was to determine the prevalence of Clostridium difficile diarrhea (CDD) and the risk for CDD associated with different oral antibiotics commonly used in the ambulatory care setting. METHODS: The prevalence of CDD was determined for enrollees in 4 UnitedHealth Group-affiliated health plans between January 1, 1992, and December 31, 1994. Cases were identified based on the presence of an inpatient or outpatient claim with a primary diagnosis of diarrhea, a pharmacy claim for a prescription drug used to treat CDD, or a physician or facility claim for the C. difficile toxin test, and were confirmed using full-text medical records. Within a retrospective cohort design, periods of risk for CDD were defined on the basis of duration of antibiotic therapy. To control for potential selection bias created by heterogeneous rates of C. difficile testing and to limit confounding due to multiple antibiotic exposures, we used a nested case-control design, restricting eligibility to subjects who underwent screening for C. difficile and who had been exposed to only 1 antibiotic risk period with a single antibiotic. RESULTS: The global prevalence of CDD in 358,389 ambulatory care enrollees was 12 per 100,000 person-years. In the nested case-control study, after controlling for other risk factors, 2 antibiotics demonstrated an increased association with CDD: cephalexin (odds ratio [OR] = 7.5, 95% CI = 1.8 to 34.7) and cefixime (OR = 6.4, 95% CI = 1.2 to 39.0). CONCLUSIONS: Although CDD is thought to occur primarily in hospitalized patients, it was found to be present in an ambulatory care population, but at a low frequency. In this population, it appeared to be associated with 2 cephalosporins but not with other types of antibiotics usually linked with nosocomial CDD. Because the frequency of C. difficile testing was shown to be more common with high-risk antibiotics, CDD may be underdiagnosed in the ambulatory care setting.

Healthcare resource use and costs associated with migraine in a managed healthcare setting.

OBJECTIVE: To compare healthcare use and associated costs in patients with migraine and patients without migraine headache. DESIGN: Retrospective review of a managed care organization's medical and pharmacy claims databases for claims filed between January 1, 1989 and June 30, 1990. PATIENTS: Patients between 18 and 64 years old with a 12-month minimum enrollment in the health plan, including enrollment for the prescription drug benefit. Migraine group (n = 1336) inclusion required a medical claim with the diagnosis of migraine headache and a pharmacy claim for a medication potentially used for migraine treatment. Comparison group (n = 1336) inclusion required at least one medical claim with no diagnosis of migraine; a pharmacy claim was not required. Comparison group patients were matched to migraine group patients by age, gender, enrollment status, and subscriber or dependent enrollment status. OUTCOME MEASURES: Total health services use, diagnosis-specific use of services, diagnostic procedures performed, comorbid conditions, medication use, and associated costs were tallied. RESULTS: Migraineurs generated nearly twice as many medical claims as comparison group patients, and nearly 2.5 times as many pharmacy claims. Number of claims generated and numbers of patients who generated claims within each of 19 diagnostic categories indicated greater comorbidity in the migraine group. Migraineurs used emergency services more than did patients in the comparison group. Total medical and pharmacy claims costs were $3.4 million for the migraine group and $2.1 million for the comparison group. The average amount paid per member-month of enrollment was significantly greater in the migraine group than in the comparison group. Comorbid conditions were responsible for a significant portion of costs in the migraine group. The migraine group incurred $83,537 for diagnostic procedures compared with $13,140 incurred by the comparison group. CONCLUSIONS: Patients with migraine had greater morbidity in general and incurred 64 percent greater costs in healthcare resource use compared with patients without migraine.

Pharmacoeconomics: a managed care perspective.

Managed care pharmacy organizations have the responsibility to promote high-quality cost-effective health care that provides value to their enrolled populations. Application of management interventions that reduce the inappropriate use of medications and enhance the appropriate use of medications that improve patient outcomes and the cost effectiveness of care can help meet these responsibilities. To accomplish these management objectives, managed care pharmacy organizations should aggressively apply the results of pharmacoeconomic studies and, where possible, participate in the conduct of these studies.