Using Randomized Controlled Trials to Estimate the Effect of Community Interventions for Childhood Asthma.

INTRODUCTION: The Centers for Disease Control and Prevention's Controlling Childhood Asthma and Reducing Emergencies initiative aims to prevent 500,000 emergency department (ED) visits and hospitalizations within 5 years among children with asthma through implementation of evidence-based interventions and policies. Methods are needed for calculating the anticipated effects of planned asthma programs and the estimated effects of existing asthma programs. We describe and illustrate a method of using results from randomized control trials (RCTs) to estimate changes in rates of adverse asthma events (AAEs) that result from expanding access to asthma interventions. METHODS: We use counterfactual arguments to justify a formula for the expected number of AAEs prevented by a given intervention. This formula employs a current rate of AAEs, a measure of the increase in access to the intervention, and the rate ratio estimated in an RCT. RESULTS: We justified a formula for estimating the effect of expanding access to asthma interventions. For example, if 20% of patients with asthma in a community with 20,540 annual asthma-related ED visits were offered asthma self-management education, ED visits would decrease by an estimated 1,643; and annual hospitalizations would decrease from 2,639 to 617. CONCLUSION: Our method draws on the best available evidence from RCTs to estimate effects on rates of AAEs in the community of interest that result from expanding access to asthma interventions.

Costs of Chronic Diseases at the State Level: The Chronic Disease Cost Calculator.

INTRODUCTION: Many studies have estimated national chronic disease costs, but state-level estimates are limited. The Centers for Disease Control and Prevention developed the Chronic Disease Cost Calculator (CDCC), which estimates state-level costs for arthritis, asthma, cancer, congestive heart failure, coronary heart disease, hypertension, stroke, other heart diseases, depression, and diabetes. METHODS: Using publicly available and restricted secondary data from multiple national data sets from 2004 through 2008, disease-attributable annual per-person medical and absenteeism costs were estimated. Total state medical and absenteeism costs were derived by multiplying per person costs from regressions by the number of people in the state treated for each disease. Medical costs were estimated for all payers and separately for Medicaid, Medicare, and private insurers. Projected medical costs for all payers (2010 through 2020) were calculated using medical costs and projected state population counts. RESULTS: Median state-specific medical costs ranged from $410 million (asthma) to $1.8 billion (diabetes); median absenteeism costs ranged from $5 million (congestive heart failure) to $217 million (arthritis). CONCLUSION: CDCC provides methodologically rigorous chronic disease cost estimates. These estimates highlight possible areas of cost savings achievable through targeted prevention efforts or research into new interventions and treatments.

Costs of asthma in the United States: 2002-2007.

BACKGROUND: The economic burden of asthma is an important measure of the effect of asthma on society. Although asthma is a costly illness, the total cost of asthma to society has not been estimated in more than a decade. OBJECTIVE: The purpose of this study is to provide the public with current estimates of the incremental direct medical costs and productivity losses due to morbidity and mortality from asthma at both the individual and national levels for the years 2002-2007. METHODS: Data came from the Medical Expenditure Panel Survey. Two-part models were used to estimate the incremental direct costs of asthma. The incremental number of days lost from work and school was estimated by negative binomial regressions and valued following the human capital approach. Published data were used to value lives lost with an underlying cause of asthma. RESULTS: Over the years 2002-2007, the incremental direct cost of asthma was $3,259 (2009 dollars) per person per year. The value of additional days lost attributable to asthma per year was approximately $301 for each worker and $93 for each student. For the most recent year available, 2007, the total incremental cost of asthma to society was $56 billion, with productivity losses due to morbidity accounting for $3.8 billion and productivity losses due to mortality accounting for $2.1 billion. CONCLUSION: The current study finds that the estimated costs of asthma are substantial, which stresses the necessity for research and policy to work toward reducing the economic burden of asthma.

Economic value of home-based, multi-trigger, multicomponent interventions with an environmental focus for reducing asthma morbidity a community guide systematic review.

CONTEXT: A recent systematic review of home-based, multi-trigger, multicomponent interventions with an environmental focus showed their effectiveness in reducing asthma morbidity among children and adolescents. These interventions included home visits by trained personnel to assess the level of and reduce adverse effects of indoor environmental pollutants, and educate households with an asthma client to reduce exposure to asthma triggers. The purpose of the present review is to identify economic values of these interventions and present ranges for the main economic outcomes (e.g., program costs, benefit-cost ratios, and incremental cost-effectiveness ratios). EVIDENCE ACQUISITION: Using methods previously developed for Guide to Community Preventive Services economic reviews, a systematic review was conducted to evaluate the economic efficiency of home-based, multi-trigger, multicomponent interventions with an environmental focus to improve asthma-related morbidity outcomes. A total of 1551 studies were identified in the search period (1950 to June 2008), and 13 studies were included in this review. Program costs are reported for all included studies; cost-benefit results for three; and cost-effectiveness results for another three. Information on program cost was provided with varying degrees of completeness: six of the studies did not provide a list of components included in their program cost description (limited cost information), three studies provided a list of program cost components but not a cost per component (partial cost information), and four studies provided both a list of program cost components and costs per component (satisfactory cost information). EVIDENCE SYNTHESIS: Program costs per participant per year ranged from $231-$14,858 (in 2007 U.S.$). The major factors affecting program cost, in addition to completeness, were the level of intensity of environmental remediation (minor, moderate, or major), type of educational component (environmental education or self-management), the professional status of the home visitor, and the frequency of visits by the home visitor. Benefit-cost ratios ranged from 5.3-14.0, implying that for every dollar spent on the intervention, the monetary value of the resulting benefits, such as averted medical costs or averted productivity losses, was $5.30-$14.00 (in 2007 U.S.$). The range in incremental cost-effectiveness ratios was $12-$57 (in 2007 U.S.$) per asthma symptom-free day, which means that these interventions achieved each additional symptom-free day for net costs varying from $12-$57. CONCLUSIONS: The benefits from home-based, multi-trigger, multicomponent interventions with an environmental focus can match or even exceed their program costs. Based on cost-benefit and cost-effectiveness studies, the results of this review show that these programs provide a good value for dollars spent on the interventions.

The economic implications of influenza vaccination for adults with asthma.

BACKGROUND: Influenza vaccination is recommended for adults with asthma. PURPOSE: This study estimates the effect of influenza vaccination on utilization of medical services and expenditures for acute and chronic respiratory conditions (ACRC) among adults with asthma. METHODS: The sample was adults aged ≥18 years self-reporting asthma in the 2003 through 2006 Medical Expenditure Panel Survey (MEPS), covering four complete influenza seasons. The dependent variables were indicators for any ACRC claims within service category and ACRC expenditures. The main independent variable was an indicator of influenza vaccination. To control for selection bias in the observational data, a nonlinear instrumental variables approach was used. The instruments were indicators for influenza in the first year of MEPS and vaccination in the year prior to MEPS. Data were analyzed in 2009. RESULTS: Adults with asthma vaccinated for influenza were 4.4 percentage points less likely to have an inpatient stay due to ACRC (95% CI = -10.8, -1.0). Influenza vaccination was associated with a $492 decrease (95% CI = -$1591, -$56) in annual ACRC nonprescription expenditures, a $224 increase (95% CI = $70, $360) in annual ACRC prescription expenditures, and a nonsignificant $216 decrease (95% CI = -$854, $248) in overall annual ACRC expenditures. CONCLUSIONS: Although there was no evidence that vaccination reduced overall ACRC expenditures, the study suggests that efforts to increase the percentage of adults with asthma who are vaccinated may bring substantial benefits in terms of reducing the prevalence and costs of hospitalization although raising prescription medication costs, possibly through improvement in compliance.

The economic impact of an urban asthma management program.

OBJECTIVES: To examine costs associated with an asthma management program that reduces asthma-related health services utilization and to calculate potential return on investment (ROI) from the Medicaid managed care plan perspective. STUDY DESIGN: Cross-sectional. METHODS: Clinical and economic data were obtained for 3298 ethnically diverse children with asthma (48% with persistent asthma) who resided in a poor urban community (Hartford, Connecticut) and were enrolled in Easy Breathing, an asthma management program for pediatricians. We calculated the cost per participating child with asthma during the first 3 years (July 1998 to June 2001) relative to the difference in costs for participating and nonparticipating children calculated by applying Medicaid reimbursement rates to data on services. RESULTS: Start-up costs were $28.95 per child with asthma in year 1, and operating costs averaged $10.28 in years 2 and 3. The mean reduction in costs was $36.72 per child per year in years 2 and 3. If Medicaid managed care plans had been charged an amount equal to program operating costs after year 1 ($10.28 per child with asthma per year), at-risk health plans could have incurred cost savings of approximately $26.44 per child with asthma per year. The potential ROI for years 2 and 3 was $3.58 per US dollar spent. CONCLUSIONS: Easy Breathing reduced overall costs of care for urban children with asthma of varying severities. If managed care plans held at risk by Medicaid had reimbursed program operating costs for participants in Easy Breathing, they would have experienced a positive ROI.