Substudy 11 Fact Sheet

An Economic Evaluation of Hospital-Based and Home-Based Intravenous Antibiotic Therapy for Individuals with Cellulitis (NA101-11)

Sponsor Organization:
University of Toronto

Rationale/Goals:
This project is one of fifteen sub-studies of the National Evaluation of the Cost-Effectiveness of Home Care Project (NA101). In Canada, intravenous (IV) therapy is most commonly prescribed for delivering antibiotics, and cellulitis is a major reason for such prescriptions. Antibiotic IV therapy has traditionally been conducted through hospital admissions. The goal of sub-study 11 was to examine the costs and outcomes of antibiotic IV therapy for individuals with cellulitis, focusing on a comparison between hospital versus home care locations. The main motivating factors behind the study were the potential to change clinical practices, the large number of patients affected, the magnitude of the resource implications, and the potential to influence clients and caregivers.

Activities:
The initial goal of a randomized control trial proved to be unattainable as emergency departments in Toronto hospitals were unable to help in the recruitment of patients due to their workloads. The study was modified to an observational cohort design with physicians deciding which patients should be treated in hospital and which could be treated at home. In several instances a lack of adequate home care services meant that many people were treated through repeat visits to emergency departments rather than strictly at home. The authors noted the new study design led to the possibility of bias and to a small sample size.

Key Findings:
The project leaders identified the following outcomes:

• Relatively few patients with cellulitis requiring IV antibiotics were treated exclusively at home or as in-patients. Nearly two-thirds of patients received care with repeated emergency department visits.
  
• Patients treated in the hospital had the highest Charlson Co-morbidity Scores and the lowest health-related quality of life scores.
  
• Patients treated at home healed faster than patients treated with multiple visits to the emergency or hospitalised patients.
  
• In-hospital care was more expensive than multiple visits to the emergency department or home care.

Implications:
The project leaders indicated that their findings are important because, in their view, insight was gained into the cost and quality of IV antibiotic care provided in different settings. Due to small sample sizes and patient differences, it was not possible to answer all the research questions, and the observational cohort study design is more prone to bias as intervention may be chosen by patients or physicians based on variables that influence the outcome. However, the study did illustrate how home care and emergency department services are now replacing hospital admissions as the main mode of treatment. Further data collection is required for more meaningful comparisons.

Evaluation Methodology:
The study was conducted at two Toronto Hospitals, over 11- and two-month periods respectively. A research coordinator conducted weekly chart reviews to find patients who met the eligibility criteria (had cellulitis and required IV antibiotics.) Patients identifed by the chart review were contacted and asked to participate in the study. Clinical and outcome data were collected for consenting patients at baseline, day 15 and day 30 (termination).


HTF Contribution to the Project:
$1,505,000 (divided among the 15 sub-studies)

Language of Report:
English

• Executive summary
• Full report