Cost Associated With the Treatment of Influenza in a Managed Care Setting

Abstract and Introduction

Objective: The purpose of this study was to assess the costs and treatments associated with influenza patients with and without secondary viral or bacterial infections in a managed care setting.
Methods: Patients with influenza diagnoses (ICD-9 = 487) were identified in the PharMetrics database between January 1, 1997 and June 30, 1998. Patients were placed into 3 cohorts: influenza only (INF), influenza plus a secondary bacterial respiratory infection (BRI), and influenza plus a secondary viral respiratory infection (VRI). The index date was defined as the date of the first occurrence of an influenza diagnosis during the study period. Medical claims were assessed from the index date to the end of the influenza episode, which was defined as the date of the last claim for influenza followed by a 90-day "clean period" during which no influenza-related charges occurred.
Results: A total of 18,000 patients met the inclusion criteria. The mean age was 29 years, and 54% were female. Approximately 93% of patients were placed in the INF cohort, and 3% each in the BRI and VRI groups. The BRI cohort had the highest mean total cost ($5593* SD = 10,939), compared with the VRI cohort ($847 SD = 1782) and INF cohort ($602 SD = 2813) (P < .0001 vs INF; P < .0001 vs VRI). This total cost disparity was primarily driven by differences in inpatient costs: BRI ($3509, SD = 9474); VRI ($208, SD = 1327); INF ($138, SD = 2145). Patients in the BRI cohort averaged 0.5 hospitalizations per patient vs 0.06 in the VRI cohort and 0.03 in the INF cohort.
Conclusions: Subjects in the BRI cohort were significantly more costly and had an increased risk of hospitalization as compared with subjects in the VRI or INF cohorts. Early intervention with antiviral agents and/or antibiotics, where appropriate, could result in significant cost savings for managed care organizations.

It is estimated that each nonpandemic and/or nonepidemic year in the United States, there are approximately 4 million to 24 million healthcare visits, 314,000 hospitalizations, and 20,000-40,000 deaths due to influenza A and B or its complications.^[1,2,3,4] The high morbidity of acute influenza illness and the subsequent secondary complications result in increased outpatient visits and hospitalizations. These effects in turn drive the estimated $4.6 billion spent each year in the United States on influenza-related direct medical costs with the total costs upwards of $12 billion per year.^[2,3,5]

It has been reported that 90% of the people who die each year of influenza are over the age of 65.^[6] This fact, coupled with the serious nature of influenza, supports the recommendation that at-risk patients, such as the elderly, immunocompromised patients, or those with chronic diseases, take prophylactic measures to guard against influenza infection.^[7] Vaccination is the primary method for prevention of influenza; however, antiviral agents also play a role in prevention as well as treatment.^[8] The goal of vaccination is primarily to prevent complications and death from influenza.^[5] However, studies show that only 20% to 60% of persons in high-risk groups are vaccinated.^[9]

Despite current recommendations, influenza vaccinations and antiviral agents are underused in the prevention and control of influenza.^[7] Furthermore, antibiotics are often inappropriately prescribed despite their ineffectiveness in treating viral influenza and the typical lack of evidence confirming bacterial etiology.^[10]

Much of the discussion of influenza treatment is based on anecdotal reports or retrospective analysis of data from the 1980s or early 1990s. Currently, little is known about the treatment and/or associated costs of influenza in a managed care setting. While it has been suggested that antiviral agents are underutilized and antibacterials inappropriately prescribed for influenza, these issues have not been addressed in conjunction with one another, nor have they accounted for differing types of influenza patients, such as those with secondary infections.

The purpose of this study was to assess the cost and treatments associated with influenza patients, with and without secondary viral or bacterial infection, using administrative claims data from a managed care setting.

© 2000  Medscape

Cite this: Cost Associated With the Treatment of Influenza in a Managed Care Setting - Medscape - Oct 03, 2000.