Cost of invasive fungal infections in the era of new diagnostics and expanded treatment options.

STUDY OBJECTIVE: To determine the true institutional cost of treating invasive fungal infections in light of recent advances in diagnostic techniques and antifungal therapies for both treatment and prophylaxis of these infections. DESIGN: Economic analysis. SETTING: Academic medical center. PATIENTS: A total of 200 patients discharged from the hospital during 2004-2005 with a diagnosis of proven, probable, or possible aspergillosis, cryptococcosis, invasive candidiasis, or zygomycosis (cases). Patients were matched in a 1:1 fashion with patients having similar underlying disease states but no invasive fungal infections (controls). MEASUREMENTS AND MAIN RESULTS: Data on demographic and clinical characteristics were collected from patients' medical records. In addition, information concerning each patient's hospitalization was recorded. Resource utilization data for a patient's entire hospitalization were collected from the hospital's charge databases and converted to costs. These data were compared between the cases and the controls. After adjusting for race-ethnicity, sex, age, and comorbid illnesses, mean total hospital cost for cases was $32,196 more than for controls (p<0.0001). Nonpharmacy costs accounted for the majority (63%) of this difference, and an additional $3996 was attributed to systemic antifungal drugs. The mean length of hospital stay was longer for cases than controls (25.8 vs 18.4 days). CONCLUSION: Treatment of patients with invasive fungal infections was associated with a significantly higher inpatient hospital cost compared with controls. However, due to new diagnostic techniques and effective antifungal therapy, the relative cost of these infections appears to be at least stable compared with the previous decade. These findings can help assess the utility of cost-avoidance strategies such as antifungal prophylaxis and application of appropriate treatment.

The economic costs to United States hospitals of invasive fungal infections in transplant patients.

BACKGROUND: Patients with a solid organ transplant (SOTs) and hematopoietic stem cell or bone marrow transplants (HSC/BMTs) are at risk of contracting invasive fungal infections (IFIs). Data on the economic burden of IFIs in the United States are sparse. METHODS: We conducted a retrospective matched cohort study using the 2004-2005 Healthcare Cost and Utilization Project Nationwide Inpatient Sample. The IFI cohort included patients with ICD-9-CM codes indicating a transplant procedure and an IFI. Matched controls (transplant recipients without an IFI) were chosen based on age (10 year categories), sex, region, hospital type, year, and transplant type. Mortality, length of stay, and costs were reported overall, by transplant type, and by type of mycosis. RESULTS: Nine thousand eight hundred ninety-six patients underwent SOT, and 4661 underwent HSC/BMT. Of these, 80 (0.8%) SOT and 111 (2.4%) HSC/BMT patients had an IFI. Mean age was 41.8 years (SOT) and 37.8 years (HSC/BMT). Aspergillosis was the most common infection. Patients with an IFI had a 5-fold increase in mortality, an additional 19.2 hospital days, and $55,400 in excess costs compared with patients without an IFI. Excess mortality, length of stay, and costs varied by type of transplant and mycosis. CONCLUSION: The clinical and economic burden of IFIs in transplant recipients may be high.

Comparative survival and cost of antifungal therapy: posaconazole versus standard antifungals in the treatment of refractory invasive aspergillosis.

BACKGROUND: Refractory invasive aspergillosis (IA) is a life-threatening condition. Cost of treatment, although secondary, is important if newer drugs are to be widely accepted. Posaconazole has been shown to have activity against aspergillosis. METHODS: Analyses were conducted to compare the effectiveness and cost of posaconazole 800 mg/day with those of standard antifungal therapy, using Walsh et al. 2007 data. All-cause mortality and total drug costs were analyzed for three patient groups: All Refractory, Refractory Non-neutropenic, and Refractory Neutropenic IA Patients. Comparative survival analysis using Kaplan-Meier estimates after censoring data at 28, 42, 84, 182, and 365 days and Cox proportional hazard method was used to estimate hazard rates after controlling for difference in baseline neutropenia. For cost analysis, only antifungal drug acquisition cost was used. RESULTS: Significantly more of the 94 patients treated with posaconazole remained alive at every time point compared with the 68 external control patients within the All Refractory group (p = 0.0001). Similar results were obtained for the other two groups. For the posaconazole-treated patients mean total drug costs were $11846 (±$12406), $12642 (±$11811), and $8903 (±$14345), and for the external controls total drug costs were $35537 (±$73059), $48097 (±$88702), and $13556 (±$16324) for the All Refractory, Refractory Non-neutropenic, and Neutropenic IA groups, respectively. Key limitations of the study included noninclusion of hospitalization or other drug costs, low patient numbers beyond 84 days, and the fact that the Walsh et al. 2007 study was completed before other newer antifungal agents (such as voriconazole and caspofungin) were available. CONCLUSIONS: Posaconazole appears to confer a survival benefit and reduced total drug cost compared with standard antifungal therapy, such as amphotericin B (lipid and nonlipid formulations), itraconazole, or both, to treat patients with probable or proven refractory IA.

Mortality, length of hospitalization, and costs associated with invasive fungal infections in high-risk patients.

PURPOSE: The mortality, length of hospitalization, and costs associated with invasive fungal infections (IFIs) in hospitalized patients were studied. METHODS: This retrospective database study used data from the 2004 Healthcare Cost and Utilization Project Nationwide In-patient Sample. Patients were selected for inclusion based on diagnostic codes corresponding to an IFI. A control group was matched to the IFI group based on high-risk conditions (i.e., cancer, infection with human immunodeficiency virus, chronic obstructive pulmonary disease, diabetes mellitus, and solid-organ, hematopoietic stem cell, or bone marrow transplant), age, sex, and hospital region and teaching status. Excess mortality, length of hospital stay, and costs were estimated as the differences between the IFI and control groups. RESULTS: A total of 11,881 patients were identified with a discharge diagnosis of an IFI who could be matched to a control. Frequent infections included candidiasis (40.2%), other mycoses (36.3%), and aspergillosis (16.4%). Patients with IFIs had a significantly higher mortality rate (15% versus 5%), mean +/- S.E. length of stay (18.7 +/- 0.4 days versus 7.3 +/- 0.1 days), and mean +/- S.E. costs ($44,726 +/- $1,255 versus $15,445 +/- $404) (p < 0.001 for all comparisons) than did patients without IFIs. The burden of IFIs varied by high-risk condition (highest for transplant recipients and patients with cancer) and type of infection (highest for candidiasis, zygomycosis, and aspergillosis). CONCLUSION: Examination of a large database showed that, compared with high-risk patients without IFIs, those with IFIs had higher mortality, a longer hospital stay, and higher costs associated with their hospitalization.