Cost-effectiveness of inhaled steroids in asthma: impact of effect on bone mineral density

The cost-effectiveness of as-needed budesonide-formoterol versus low-dose inhaled corticosteroid maintenance therapy in patients with mild asthma in Canada

BACKGROUND

The Global Initiative for Asthma recommends the use of as-needed low-dose inhaled corticosteroid (ICS)-formoterol as a preferred controller therapy for patients with mild asthma. These recommendations were based, in part, on evidence from the SYGMA 1 and 2 studies of as-needed budesonide-formoterol. This analysis aimed to compare the cost-effectiveness of as-needed budesonide-formoterol to low-dose maintenance ICS plus as-needed short-acting β2-agonist (SABA) in patients with mild asthma.

METHODS

A Markov cohort model was designed that included three possible health states (non-exacerbation, severe exacerbation, and death) to compare as-needed budesonide-formoterol 200-6 μg to twice-daily budesonide 200 μg maintenance therapy (low-dose ICS) plus as-needed terbutaline 0.5 mg (SABA). The deterministic base-case analysis used severe exacerbation, adverse event (AE), and healthcare resource use data from SYGMA 2, and was conducted from a Canadian public payer perspective with a 50-year time horizon, and a discount rate of 1.5% per annum. Moderate exacerbation was modelled on data from SYGMA 1 in sensitivity analyses. Utility values were derived from SYGMA 2 quality of life data. All-cause- and asthma-related mortality rates and costs (reported in 2019 Canadian dollars) were based on published data, using Canada-specific values where available. One-way deterministic sensitivity, probabilistic sensitivity, and eight scenario analyses were conducted to examine the robustness of the results.

RESULTS

As-needed budesonide-formoterol was the dominant treatment option in the base-case analysis, providing incremental cost savings of $9882 per patient and quality-adjusted life year (QALY) gains of 0.002 versus low-dose maintenance ICS plus as-needed SABA over a 50-year time horizon. Using a willingness-to-pay threshold of $50,000/QALY ($100,000/QALY), as-needed budesonide-formoterol had a 94% (95%) probability of being cost-effective compared with maintenance ICS plus as-needed SABA. Cost-saving was mostly driven by lower overall medication and AE-related costs. As-needed budesonide-formoterol remained the dominant treatment in sensitivity and scenario analyses.

CONCLUSIONS

As-needed budesonide-formoterol is a cost-saving option for the treatment of mild asthma from the perspective of the Canadian public payer compared with low-dose maintenance ICS plus as-needed SABA.

The cost-effectiveness of as-needed budesonide/formoterol versus low-dose inhaled corticosteroid maintenance therapy in patients with mild asthma in the UK

BACKGROUND

As-needed budesonide/formoterol is effective in patients with mild asthma for whom low-dose inhaled corticosteroid (ICS) maintenance therapy is appropriate. We assessed the cost-effectiveness of this regimen versus maintenance low-dose ICS plus as-needed short-acting β2-agonist (SABA).

METHODS

A probabilistic Markov cohort model was developed that simulated time within/outside severe asthma exacerbations, conducted from a UK NHS perspective with a 70-year time horizon. Clinical efficacy inputs were derived from the SYGMA 2 trial. Patients with mild asthma eligible for low-dose maintenance ICS therapy received as-needed budesonide/formoterol 200/6 μg or twice-daily budesonide 200 μg maintenance therapy plus as-needed terbutaline 0.5 mg. A severe exacerbation was defined as worsening asthma requiring systemic corticosteroid use alone/in combination with an emergency department visit, or hospitalisation for acute asthma. Utility values were derived from SYGMA 2 EQ-5D-5L data, and all-cause- and asthma-related mortality, reduction in utility of an exacerbation, and costs were based on published data. The base-case analysis discount rate was 3.5%. Model robustness was evaluated with one-way sensitivity, probabilistic sensitivity, and two scenario analyses.

RESULTS

On average, as-needed budesonide/formoterol was associated with a £292.99 cost saving and quality-adjusted life year (QALY) gains of 0.001 versus ICS + SABA. At a willingness-to-pay of £20,000/QALY, as-needed budesonide/formoterol had >85% probability of being cost-effective versus ICS + SABA. Key drivers were budesonide/formoterol and budesonide maintenance annual exacerbation rates, mean daily budesonide/formoterol inhalations, and costs and outcomes discount rates.

CONCLUSIONS

From a UK healthcare payer perspective, as-needed budesonide/formoterol is a cost-effective option for the treatment of mild asthma versus regular ICS.

Modeling Healthcare Costs Attributable to Secondhand Smoke Exposure at Home among South Korean Children

Children exposed to secondhand smoke (SHS) are at increased risk for disease. We sought to estimate the medical costs among Korean children who were exposed to SHS at home. A Markov model was developed, including five diseases (asthma, acute otitis media, acute bronchitis, pneumonia and sudden infant death syndrome) that were significantly associated with SHS in children based on a systematic review. The time horizon of the analysis was 20 years (from birth to adulthood), and the cycle length was 1 week. The direct healthcare costs were discounted annually at 5%. Univariate and probabilistic sensitivity analyses were conducted. The Markov model estimated the healthcare costs for 20 years as 659.61 USD per exposed child, an increase of approximately 30% compared to the cost per unexposed child (507.32 USD). Sensitivity analysis suggested that the younger the age of the exposure, the greater the incremental healthcare costs incurred, implying that infants and young children were especially vulnerable to the SHS exposure. Findings of this study could provide key baseline data for future economic evaluations on SHS control policies in South Korea.

A Systematic Review of Decision-Analytic Models for Evaluating Cost-Effectiveness of Asthma Interventions

OBJECTIVE

To demonstrate the landscape of model-based economic studies in asthma and highlight where there is room for improvement in the design and reporting of studies.

DESIGN

A systematic review of the methodologies of model-based, cost-effectiveness analyses of asthma-related interventions was conducted. Models were evaluated for adherence to best-practice modeling and reporting guidelines and assumptions about the natural history of asthma.

METHODS

A systematic search of English articles was performed in MEDLINE, EMBASE, and citations within reviewed articles. Studies were summarized and evaluated based on their adherence to the Consolidated Health Economic Evaluation Reporting Standards (CHEERS). We also studied the underlying assumptions about disease progression, heterogeneity in disease course, comorbidity, and treatment effects.

RESULTS

Forty-five models of asthma were included (33 Markov models, 10 decision trees, 2 closed-form equations). Novel biological treatments were evaluated in 12 studies. Some of the CHEERS' reporting recommendations were not satisfied, especially for models published in clinical journals. This was particularly the case for the choice of the modeling framework and reporting on heterogeneity. Only 13 studies considered any subgroups, and 2 explicitly considered the impact of comorbidities. Adherence to CHEERS requirements and the quality of models generally improved over time.

CONCLUSION

It would be difficult to replicate the findings of contemporary model-based evaluations of asthma-related interventions given that only a minority of studies reported the essential parameters of their studies. Current asthma models generally lack consideration of disease heterogeneity and do not seem to be ready for evaluation of precision medicine technologies.

Incorporating adherence in cost-effectiveness analyses of asthma: a systematic review

Aims: Non-adherence is associated with poor clinical outcomes among patients with asthma. While cost-effectiveness analysis (CEA) is increasingly used to inform value assessment of the interventions, most do not take into account adherence in the analyses. This study aims to: (1) Understand the extent of studies considering adherence as part of the economic analyses, and (2) summarize the methods of incorporating adherence in the economic models. Materials and methods: A literature search was performed from the inception to February 2018 using four databases: PubMed, EMBASE, NHS EED, and the Tufts CEA registry. Decision model-based CEA of asthma were identified. Outcomes of interest were the number of studies incorporating adherence in the economic models, and the incorporating methods. All data were extracted using a standardized data collection form. Results: From 1,587 articles, 23 studies were decision model-based CEA of asthma, of which four CEA (17.4%) incorporated adherence in the analyses. Only the method of incorporating adherence by adjusting treatment effectiveness according to adherence levels was demonstrated in this review. Two approaches were used to derive the associations between adherence and effectiveness. The first approach was to apply a mathematical formula, developed by an expert panel, and the second was to extrapolate the associations from previous published studies. The adherence-adjusted effectiveness was then incorporated in the economic models. Conclusions: A very low number of CEA of asthma incorporated adherence in the analyses. All the CEA adjusted treatment effectiveness according to adherence levels, applied to the economic models.

Pharmacogenomic test that predicts response to β2-agonists in adults with asthma is cost effective

BACKGROUND

Pharmacogenomic tests that predict which asthma patients are likely to respond to β₂-agonists hold promise to improve care for asthma.

OBJECTIVE

To identify the clinical and economic circumstances under which a pharmacogenomic test that predicts response to β₂-agonists might or might not be an appropriate, cost-effective option.

METHODS

We synthesized published data on clinical and economic outcomes in adults 18-35 to project 10-year costs, quality-adjusted life years and cost-effectiveness of pharmacogenomic testing for β₂-agonist response.

RESULTS

Pharmacogenomic testing for β₂-agonist response conferred a cost-effectiveness ratio of $13,700 per quality-adjusted life year gained compared with no testing.

CONCLUSION

Pharmacogenomic testing for β₂-agonist response in individuals with asthma is potentially cost effective and should be pursued by test developers.

Pharmacogenomic test that predicts response to inhaled corticosteroids in adults with asthma likely to be cost-saving

AIM

To identify the clinical and economic circumstances under which a pharmacogenomic test that predicts response to inhaled corticosteroids might be a cost-effective option for individuals with asthma.

MATERIALS & METHODS

We synthesized published data on clinical and economic outcomes to project 10-year costs, quality-adjusted life-years and cost-effectiveness of pharmacogenomic testing for inhaled corticosteroid response. We assumed the pharmacogenomic test cost was $500 with a sensitivity and specificity of 84 and 98%, respectively. These were varied in sensitivity analyses.

RESULTS

Both strategies, pharmacogenomic testing for inhaled corticosteroid response and no testing conferred 7.1 quality-adjusted life-years. Compared with no testing, pharmacogenomic testing costs less.

CONCLUSION

Pharmacogenomic testing for asthma is cost-saving and noninferior in improving health. Original submitted 19 November 2014; Revision submitted 23 February 2015.

The economic burden of inappropriate drug prescribing, lack of adherence and compliance, adverse drug events in older people: a systematic review

Adverse drug events (ADEs) are an increasingly relevant issue for healthcare systems as they are associated with poorer health outcomes and avoidable misuse of resources. The rates of ADEs are higher in the elderly population, as many older patients have comorbidities, multiple drug prescriptions and deteriorated physical and cognitive functioning. The occurrence of ADEs can lead to a perceived lack of therapy efficacy and further underuse or suboptimal adherence in elderly people, with detrimental clinical outcomes. The present article systematically reviews the studies evaluating the economic impact of ADEs occurring as consequence of poor therapy adherence, inappropriate drug use, underuse of effective treatments and poor adherence, medication errors, drug-drug and drug-disease interactions.A Medline systematic literature review of studies evaluating the economic consequences of inappropriate drug prescribing, lack of adherence and compliance, ADEs in older people was performed. English-language articles were screened through a three-step approach (title review, abstract review, full article review) to select pertinent studies quantitatively evaluating costs. We systematically reviewed evidence from767 articles. After title, abstract and full text review, 21 articles were found to measure economic implications ofADEs, inappropriate drug prescribing and poor adherence in elderly patients. Studies suggested that the economic impact of these undesired effects is substantial: hospital costs were the main cost driver, with a relevant part of them being preventable (consequences of inappropriate prescribing). Healthcare costs for unused drug wastage and destruction were also surprisingly high.Although economic evidence in elderly patients is still limited, all studies seemed to confirm that the financial burden due to pharmacological treatment issues is relevant in elderly people. Including economic effects of adverse events in pharmacoeconomic analysis would be beneficial to improve the reliability of results. Preliminary evidence suggests that programmes aimed at comprehensively assessing geriatric conditions, detecting 'high-risk' prescriptions and training patients to comply with prescribed therapies could be costeffective measures to reduce the burden of ADEs.

A simulation model of building intervention impacts on indoor environmental quality, pediatric asthma, and costs

BACKGROUND

Although indoor environmental conditions can affect pediatric asthmatic patients, few studies have characterized the effect of building interventions on asthma-related outcomes. Simulation models can evaluate such complex systems but have not been applied in this context.

OBJECTIVE

We sought to evaluate the impact of building interventions on indoor environmental quality and pediatric asthma health care use, and to conduct cost comparisons between intervention and health care costs and energy savings.

METHODS

We applied our previously developed discrete event simulation model (DEM) to simulate the effect of environmental factors, medication compliance, seasonality, and medical history on (1) pollutant concentrations indoors and (2) asthma outcomes in low-income multifamily housing. We estimated health care use and costs at baseline and subsequent to interventions, and then compared health care costs with energy savings and intervention costs.

RESULTS

Interventions, such as integrated pest management and repairing kitchen exhaust fans, led to 7% to 12% reductions in serious asthma events with 1- to 3-year payback periods. Weatherization efforts targeted solely toward tightening a building envelope led to 20% more serious asthma events, but bundling with repairing kitchen exhaust fans and eliminating indoor sources (eg, gas stoves or smokers) mitigated this effect.

CONCLUSION

Our pediatric asthma model provides a tool to prioritize individual and bundled building interventions based on their effects on health and costs, highlighting the tradeoffs between weatherization, indoor air quality, and health. Our work bridges the gap between clinical and environmental health sciences by increasing physicians' understanding of the effect that home environmental changes can have on their patients' asthma.

Modeling asthma exacerbations through lung function in children

BACKGROUND

Formal economic evaluation using a model-based approach is playing an increasingly important role in health care decision making.

OBJECTIVE

To develop a model by using an objective measure of lung function-- prebronchodilator FEV(1) as a percent of predicted (FEV(1)% predicted)--as the primary independent factor to predict the frequency of adverse events related to the exacerbation of asthma on a population level.

METHODS

We developed a Markov simulation model of childhood asthma by using data from the Childhood Asthma Management Program. The primary outcomes were the result of asthma exacerbations defined as hospitalizations, emergency department (ED) visits, and the need for oral corticosteroid therapy. Predicted monthly frequencies for each acute event were based on negative binomial regression equations estimated from the placebo arm of the Childhood Asthma Management Program with covariates of age, prebronchodilator FEV(1)% predicted, time in study, prior hospitalizations, and prior nocturnal awakenings.

RESULTS

Simulated versus observed mean number of acute events were similar within the placebo and treatment groups. While the trial demonstrated treatment effects of 48% reduction in hospitalizations, 46% reduction in ED visits, and 44% reduction in the need for oral corticosteroid therapy at 48 months, the model simulated similar reductions of 49% in hospitalizations, 41% in ED visits, and 46% in the need for oral corticosteroid therapy.

CONCLUSIONS

Our findings suggest that longitudinal intervention effects may be modeled through FEV(1)% predicted to estimate hospitalizations, ED visits, and need for oral corticosteroid therapy in childhood asthma for planning and evaluation purposes.

The effects of indoor environmental exposures on pediatric asthma: a discrete event simulation model

BACKGROUND

In the United States, asthma is the most common chronic disease of childhood across all socioeconomic classes and is the most frequent cause of hospitalization among children. Asthma exacerbations have been associated with exposure to residential indoor environmental stressors such as allergens and air pollutants as well as numerous additional factors. Simulation modeling is a valuable tool that can be used to evaluate interventions for complex multifactorial diseases such as asthma but in spite of its flexibility and applicability, modeling applications in either environmental exposures or asthma have been limited to date.

METHODS

We designed a discrete event simulation model to study the effect of environmental factors on asthma exacerbations in school-age children living in low-income multi-family housing. Model outcomes include asthma symptoms, medication use, hospitalizations, and emergency room visits. Environmental factors were linked to percent predicted forced expiratory volume in 1 second (FEV1%), which in turn was linked to risk equations for each outcome. Exposures affecting FEV1% included indoor and outdoor sources of NO2 and PM2.5, cockroach allergen, and dampness as a proxy for mold.

RESULTS

Model design parameters and equations are described in detail. We evaluated the model by simulating 50,000 children over 10 years and showed that pollutant concentrations and health outcome rates are comparable to values reported in the literature. In an application example, we simulated what would happen if the kitchen and bathroom exhaust fans were improved for the entire cohort, and showed reductions in pollutant concentrations and healthcare utilization rates.

CONCLUSIONS

We describe the design and evaluation of a discrete event simulation model of pediatric asthma for children living in low-income multi-family housing. Our model simulates the effect of environmental factors (combustion pollutants and allergens), medication compliance, seasonality, and medical history on asthma outcomes (symptom-days, medication use, hospitalizations, and emergency room visits). The model can be used to evaluate building interventions and green building construction practices on pollutant concentrations, energy savings, and asthma healthcare utilization costs, and demonstrates the value of a simulation approach for studying complex diseases such as asthma.

The effects of corticosteroids on bone growth and bone density

OBJECTIVE

To define the effects of both parenteral and inhaled corticosteroids on bone growth in children and the development of osteopenia and osteoporosis in children and adults.

DATA RESOURCES

Articles in PubMed and MEDLINE published from 1983 to 2008 were searched. Keywords used included corticosteroids and bone growth, osteopenia, osteoporosis, and bisphosphonates.

STUDY SELECTION

Publications reviewed include randomized, placebo-controlled studies of both children and adults.

RESULTS

Because systemic and high-dose inhaled corticosteroids affect bone growth of children taking these medications, stadiometry should be used to measure the growth of children. Osteoporosis due to repetitive courses of oral or parenteral corticosteroids and inhaled corticosteroids can develop gradually in the aging adult. Prophylaxis against osteoporosis requires an index of suspicion, assessment of bone density, supplemental calcium and vitamin D, and use of bisphosphonates to prevent bone fractures that could compromise the patient's quality of life.

CONCLUSION

Preventing corticosteroid-induced effects on bone metabolism can allow effective treatment of allergic disease without long-term adverse effects.

Obstructive lung disease models: what is valid?

Use of disease simulation models has led to scrutiny of model methods and demand for evidence that models credibly simulate health outcomes. We sought to describe recent obstructive lung disease simulation models and their validation. Medline and EMBASE were used to identify obstructive lung disease simulation models published from January 2000 to June 2006. Publications were reviewed to assess model attributes and four types of validation: first-order (verification/debugging), second-order (comparison with studies used in model development), third-order (comparison with studies not used in model development), and predictive validity. Six asthma and seven chronic obstructive pulmonary disease models were identified. Seven (54%) models included second-order validation, typically by comparing observed outcomes to simulations of source study cohorts. Seven (54%) models included third-order validation, in which modeled outcomes were usually compared qualitatively for agreement with studies independent of the model. Validation endpoints included disease prevalence, exacerbation, and all-cause mortality. Validation was typically described as acceptable, despite near-universal absence of criteria for judging adequacy of validation. Although over half of recent obstructive lung disease simulation models report validation, inconsistencies in validation methods and lack of detailed reporting make assessing adequacy of validation difficult. For simulation modeling to be accepted as a tool for evaluating clinical and public health programs, models must be validated to credibly simulate health outcomes of interest. Defining the required level of validation and providing guidance for quantitative assessment and reporting of validation are important future steps in promoting simulation models as practical decision tools.

[Inhaled corticosteroids in asthma: a medico-economic analysis of clinical trials]

BACKGROUND

Asthma is a chronic disease with a heavy economic burden in terms of public health on account of its clinical impact and consequences on quality of life and costs. Its management is based on pharmacological measures with inhaled corticosteroids playing a large role. The objective of this study was to undertake an analysis of the published literature of medico-economic trials of the use of inhaled corticosteroids.

METHODS

A review of the literature from 1990 to 2007 was undertaken with separate analyses of studies of inhaled steroids alone and those looking at combined preparations.

RESULTS

The costs of asthma vary greatly depending on the clinical management. Analysis of the published clinical trials showed that the addition of inhaled steroids increased the total cost. When efficacy is taken into account the economic results are acceptable for developed societies. The use of inhaled steroids as maintenance therapy, or maintenance and symptomatic therapy, was always cost effective.

CONCLUSION

These results are based on data from clinical trials. They need to be confirmed by large scale observational studies using validated criteria of effectiveness.

Cost-effectiveness of omalizumab in adults with severe asthma: results from the Asthma Policy Model

BACKGROUND

Omalizumab (trade name Xolair) is approved by the US Food and Drug Administration for treatment of moderate-to-severe allergic asthma. Given the high acquisition cost of omalizumab, its role and cost-effectiveness in disease management require definition.

OBJECTIVE

We sought to identify the clinical and economic circumstances under which omalizumab might or might not be a cost-effective option by using a mathematic model.

METHODS

We merged published data on clinical and economic outcomes (including acute event incidence, frequency/severity of hospitalizations, and health-related quality of life) to project 10-year costs, quality-adjusted life years (QALYs), and cost-effectiveness of treatment with omalizumab in addition to inhaled corticosteroids. Sensitivity analyses were conducted by using input data ranges from a variety of sources (published clinical trials and observational databases).

RESULTS

For patients with baseline acute event rates, omalizumab conferred an additional 1.7 quality-adjusted months at an incremental cost of $131,000 over a 10-year planning horizon, implying a cost-effectiveness ratio of $821,000 per QALY gained. For patients with 5 times the baseline acute event rate, the cost-effectiveness ratio was $491,000 per QALY gained. The projected cost-effectiveness ratio could fall within a range of other programs that are widely considered to be cost-effective if the cost of omalizumab decreases to less than $200.

CONCLUSION

Omalizumab is not cost-effective for most patients with severe asthma. The projected cost-effectiveness ratios could fall within a favorable range if the cost of omalizumab decreases significantly.

CLINICAL IMPLICATIONS

Based on the high cost of omalizumab, it is especially important that clinicians explore alternative medications for asthma before initiating omalizumab.

Advances in adult asthma 2006: its risk factors, course, and management

This Advances article updates our understanding of risk factors for asthma and its course and management. Studies relevant to clinical practice are discussed, with special attention to their clinical research methods.

Analysis of bone mineral density and turnover in patients with cystic fibrosis: associations between the IGF system and inflammatory cytokines

BACKGROUND

Cystic fibrosis (CF) patients present an increased risk of osteoporosis, and increased fracture rate. Several factors have been identified as modulators of bone metabolism and bone mineral density (BMD).

AIMS

To evaluate BMD and serum markers of bone turnover and establish their relationships with serum concentrations of interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF)-alpha, IGF-I, IGF-II, IGF binding protein (IGFBP)-2, IGFBP-3, and parathyroid hormone (PTH) in young adult CF patients.

METHODS

Seventeen young adult CF patients (4 M, 13 F; mean age: 26.6 +/- 1.1 years) were enrolled in the study and analysed as a whole and as two subgroups according to the Shwachman-Kulczycki score. BMD was assessed at the lumbar spine (L1-L4) by dual energy X-ray absorptiometry (DXA Hologic QDR 2000). Bone turnover was assessed by measuring serum levels of osteocalcin (OC) and serum carboxyterminal propeptide of type I collagen (PICP) as markers of bone formation, and serum cross-linked carboxyterminal telopeptide of type I collagen (ICTP) as a marker of bone resorption. Serum IGFs, IGFBPs, and cytokines were assayed using special commercial kits. Daily calcium intake and weekly physical activity were estimated by questionnaires. Forced expiratory volume in one second was used to assess pulmonary function.

RESULTS

Lumbar BMD was normal, although there was a tendency to be lower in the patients with a lower clinical score. Both OC and PICP were increased, whereas ICTP was normal. Lumbar BMD was positively correlated with pulmonary function. IL-6 and C-reactive protein (markers of inflammation) were inversely correlated with PICP. Serum ICTP levels were correlated with serum IGF-I levels. No significant relationship was detected among lumbar BMD, markers of bone turnover and PTH, IGF-I, IGF-II, IGFBP-2, IGFBP-3, TNF-alpha, IL-1beta, and body mass index Z-score.

CONCLUSIONS

Bone turnover is abnormal in CF patients. Young adult CF patients with satisfying clinical status and nutritional conditions have normal BMD and increased serum OC and PICP levels.