A multiple cause-of-death analysis of asthma mortality in the United States, 1990-2001

At-home asthma mortality unchanged despite declining mortality in other settings: US death certificate data (2000-2019)

BACKGROUND

Asthma mortality rates in the United States have declined since 1999; however, asthma mortality by place of death has not been comprehensively evaluated.

OBJECTIVE

To evaluate temporal trends in asthma mortality rates and place of death in the United States.

METHODS

We conducted a population-based analysis using data from the Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research platform to evaluate deaths with asthma as the underlying cause (2000-2019) among US residents of all ages. Absolute numbers of asthma-related deaths were described by place of death. Counts were applied to US Census Bureau population counts to calculate mortality rates per 100,000 persons.

RESULTS

In the 20-year period evaluated, 67,695 asthma deaths were registered in the United States. An overall 32% decline in the asthma mortality rate was observed, from 1.43 to 0.98 per 100,000 persons from 2000 to 2019, respectively. Although asthma mortality rates declined in all medical facility locations, the at-home asthma mortality rate remained stable (0.32 and 0.34 per 100,000 persons in 2000 and 2019, respectively). Consequently, the proportion of at-home asthma deaths increased from 23% in 2000 to 2001 to 36% in 2018 to 2019. The distribution of place of death varied by age, sex, race, ethnicity, and geographic region.

CONCLUSION

Despite an overall decline in asthma mortality in the United States, at-home asthma mortality has remained unchanged. In recent years, more than one-third of asthma deaths have occurred at home. These findings warrant further study and underscore the importance of increased efforts to identify and treat uncontrolled asthma across demographic groups.

Analysis of Multiple Causes of Death: A Review of Methods and Practices

BACKGROUND

Research and reporting of mortality indicators typically focus on a single underlying cause of death selected from multiple causes recorded on a death certificate. The need to incorporate the multiple causes in mortality statistics-reflecting increasing multimorbidity and complex causation patterns-is recognized internationally. This review aims to identify and appraise relevant analytical methods and practices related to multiple causes.

METHODS

We searched Medline, PubMed, Scopus, and Web of Science from their incept ion to December 2020 without language restrictions, supplemented by consultation with international experts. Eligible articles analyzed multiple causes of death from death certificates. The process identified 4,080 items of which we reviewed 434 full-text articles.

RESULTS

Most articles we reviewed (76%, n = 332) were published since 2001. The majority of articles examined mortality by "any- mention" of the cause of death (87%, n = 377) and assessed pairwise combinations of causes (57%, n = 245). Since 2001, applications of methods emerged to group deaths based on common cause patterns using, for example, cluster analysis (2%, n = 9), and application of multiple-cause weights to re-evaluate mortality burden (1%, n = 5). We describe multiple-cause methods applied to specific research objectives for approaches emerging recently.

CONCLUSION

This review confirms rapidly increasing international interest in the analysis of multiple causes of death and provides the most comprehensive overview, to our knowledge, of methods and practices to date. Available multiple-cause methods are diverse but suit a range of research objectives. With greater availability of data and technology, these could be further developed and applied across a range of settings.

Temporal trends of hospitalizations, comorbidity burden and in-hospital outcomes in patients admitted with asthma in the United States: Population-based study

BACKGROUND

Asthma is a prevalent chronic respiratory condition and remains a common cause for hospitalization. However, contemporary data on asthma hospitalization rates, comorbidity burden, and in-hospital outcomes are lacking.

METHODS

Survey-weighted analysis of hospitalization records with a primary diagnosis of asthma using data from the US National (Nationwide) Inpatient Sample between 2004 and 2017. Outcomes were number of hospitalizations per 100,000 population and in-hospital outcomes including receipt of ventilation, length of stay, and hospital costs. Patient and admission characteristics and comorbidity burden were examined over time. Multivariable logistic and linear regression models were fitted for over-time risks of the outcomes.

RESULTS

Among 3,098,863 asthma admissions between 2004 and 2017, mean (±SD) age was 29 (±25), 57% females, 36% White, 40% had Medicaid as primary payer. During 2004-2017, asthma hospitalizations declined from 89 to 56 per 100,000 population; length of stay remained overall stable; median (interquartile range IQR) inflation-adjusted hospital costs doubled from $8,446 (9,227) in 2004 to $17,756 (19,434) in 2017. Common comorbidities in patients admitted with asthma were hypertension and diabetes in adults, but gastroesophageal reflux disease, obstructive sleep apnoea, anemia, and obesity in children. Over time, the prevalence of mental illness increased by >50%. Severe asthma (IRR, 2.48; 95%CI: 2.27-2.72) and psychoses (IRR, 1.10; 1.05-1.14) were predictors of prolonged hospitalization. Asian/Pacific Islanders were more likely to receive ventilation (OR: 2.35; 1.73-3.20) than White patients. Hospital costs were significantly higher in females and adults with hypertension (coefficient, 1405.2; 283.1-2527.4) or psychoses (coefficient, 1978.4; 674.9-3282.0).

CONCLUSIONS

US asthma hospitalization rates fluctuated in earlier years but declined over time, which may reflect improvements in community care and declining asthma prevalence. Comorbidity burden, including mental illness, increased over time and is associated with in-hospital outcomes. This highlights the changing landscape of asthma admissions which may inform redesigning services to support pre-hospitalization asthma care and help further reduce admissions, particularly among patients with multimorbidity.

Design of peptides with high affinity binding to a monoclonal antibody as a basis for immunotherapy

About half of the US population is sensitized to one or more allergens, as found by a National Health and Nutrition Examination Survey (NHANES). The most common treatment for seasonal allergic responses is the daily use of oral antihistamines, which can control some of the symptoms, but are not effective for nasal congestion, and can be debilitating in many patients. Peptide immunotherapy is a promising new approach to treat allergic airway diseases. The small size of the immunogens cannot lead to an unwanted allergic reaction in sensitized patients, and the production of peptides with sufficient amounts for immunotherapy is time- and cost-effective. However, it is not known what peptides are the most effective for an immunotherapy of allergens. We previously produced a unique monoclonal antibody (mAb) E58, which can inhibit the binding of multiple groups of mAbs and human IgEs from patients affected by the major group 1 allergens of ragweed (Amb a 1) and conifer pollens (Jun a 1, Cup s 1, and Cry j 1). Here, we demonstrated that a combined approach, starting from two linear E58 epitopes of the tree pollen allergen Jun a 1 and the ragweed pollen allergen Amb a 1, and residue modifications suggested by molecular docking calculations and peptide design could identify a large number of high affinity binding peptides. We propose that this combined experimental and computational approach by structural analysis of linear IgE epitopes and peptide design, can lead to potential new candidates for peptide immunotherapy.

Demographic, lifestyle and comorbid risk factors for all-cause mortality in a Danish cohort of middle-aged adults with incident asthma

OBJECTIVE

We aimed to identify factors associated with all-cause mortality in adults with incident asthma.

DESIGN AND SETTING

Cross-sectional cohort study, in the metropolitan areas of Copenhagen and Aarhus, Denmark.

PARTICIPANTS

Adults aged 50-64 years enrolled in the Danish Diet, Cancer, and Health cohort were followed up from baseline (1993-1997) in the National Patients Registry for first-time admissions for asthma and vital status. We defined incident asthma as at least one first-time hospital admission with asthma as the primary registered diagnosis between baseline and end of follow-up (2013) in participants without previously known asthma. Among the cohort comprising 57 053 individuals, we identified 785 adults (aged 50-64) with incident asthma, of whom 76 died during follow-up.

PRIMARY AND SECONDARY OUTCOME MEASURES

Baseline reported socioeconomic and lifestyle traits, and comorbidities associated with all-cause mortality.

RESULTS

Self-reported leisure-time physical activity was associated with a substantial reduction in risk with an HR of 0.53 (95% CI 0.33 to 0.85). Being male, single and having a diagnosis of hypertension or diabetes were associated with an increased risk of all-cause mortality with an HR of 1.83 (95% CI 1.14 to 2.38), 2.16 (95% CI 2.06 to 4.40), 2.47 (95% CI 1.54 to 3.95) and of 2.42 (95% CI 0.96 to 6.11), respectively.

CONCLUSIONS

This long-term study of adults with hospital contacts for incident asthma revealed that self-reported leisure-time physical activity is associated with an approximately 50% reduction in all-cause mortality. In contrast, both hypertension and diabetes were associated with a higher risk of mortality.

Phenotype-Guided Asthma Therapy: An Alternative Approach to Guidelines

Despite recent advances in therapy, a substantial proportion of asthmatics remain not well controlled. The classical stepwise approach to pharmacological therapy in adult asthma recommends that treatment is progressively stepped up by increasing the inhaled corticosteroid (ICS) dose or by adding another controller medication- to achieve symptom control and reduce the risk of exacerbations, and stepped down after a period of control. In general, asthma guideline recommendations do not reflect that there are significant differences between ICS in terms of potency. Moreover, they do not consider efficacy and safety separately, incorrectly assuming that "low" and "high" dose categories inevitably correspond with low and high risk of systemic effects. Another point of criticism is the fact that guidelines do not take into account the inflammatory profile of the patient, although substantial groups of patients with mild and moderate asthma have little evidence of "T2-high" inflammation, and by extension are likely to show a poor response to ICS treatment. On the other hand, the latest version of the Global Initiative for Asthma (GINA) equally recommends regular ICS and ICS/formoterol as needed to prevent exacerbations in step 2 patients, without taking into consideration that the therapeutic objectives (exacerbations, symptoms) may differ between individual patients and that different goals may warrant distinct treatment strategies. In this review, we bring to the table several controversial issues concerning asthma treatment and suggest an alternative proposal that takes into consideration the potential side effects of high ICS doses, the patient's inflammatory profile and the therapeutic goals to be achieved.

Pharmacotherapeutic management of asthma in pregnancy and the effect of sex hormones

INTRODUCTION

Asthma is a common medical condition that can frequently affect pregnancy, and thus optimal management of asthma in pregnancy is important for both mother and baby. This article reviews recent developments of asthma pharmacotherapy and provides emerging data on the safety of asthma controller medications and biological therapies in pregnancy. The authors highlight the clinical outcomes of asthma during pregnancy, and summarize emerging new data related to the influence of sex hormones and fetal sex on asthma severity.

AREAS COVERED

This review of asthma pharmacotherapy during pregnancy examines the recent guidelines and reports the most pertinent publications on safety data and asthma management.

EXPERT OPINION

Asthma management during pregnancy follows the same principles as that of non-pregnant asthma. The available data for most asthma medications are reassuring, however there is a lack of adequate safety data available because pregnant women are generally excluded from clinical trials. More clarity is needed in guidelines regarding the management of asthma in pregnancy, and high-quality randomized control trials are required to strengthen the evidence base and inform future guidelines. In particular, safety studies examining biological therapies in pregnant women with severe asthma are needed.

A Proposed Approach to Chronic Airway Disease (CAD) Using Therapeutic Goals and Treatable Traits: A Look to the Future

Chronic airflow obstruction affects a wide range of airway diseases, the most frequent of which are asthma, COPD, and bronchiectasis; they are clearly identifiable in their extremes, but quite frequently overlap in some of their pathophysiological and clinical characteristics. This has generated the description of new mixed or overlapping disease phenotypes with no clear biological grounds. In this special article, a group of experts provides their perspective and proposes approaching the treatment of chronic airway disease (CAD) through the identification of a series of therapeutic goals (TG) linked to treatable traits (TT) - understood as clinical, physiological, or biological characteristics that are quantifiable using biomarkers. This therapeutic approach needs validating in a clinical trial with the strategy of identification of TG and treatment according to TT for each patient independently of their prior diagnosis.

Use of population data for assessing trends in work-related asthma mortality

PURPOSE OF REVIEW

Work-related asthma has been associated with poorer asthma control and frequent unscheduled healthcare visits, and can be fatal. Case reports of work-related asthma deaths are rare, but can initiate efforts to prevent additional cases. We reviewed relevant literature and data sources to evaluate whether analyzing mortality data at the population level can help identify potential sources of exposures that contribute to work-related asthma.

RECENT FINDINGS

A limited number of population-based studies have addressed work-related asthma mortality. Data on asthma mortality are derived from death certificates using the International Classification of Diseases (ICD) as a standard for coding cause. However, no discrete code for work-related asthma is available. Analysis of asthma mortality relative to industries and occupations appears to identify high-risk jobs that were not identified by analyzing asthma morbidity data.

SUMMARY

Beyond recognized work-related asthma deaths, it is possible that occupational exposures have contributed to other asthma deaths that have gone unnoticed and could potentially be identified by the analysis of mortality data at the population level. Such analyses in the United States appear to assist in recognizing high-risk occupations and industries. Additional analyses would be possible if a work-related asthma ICD code were available.

Using cluster analysis to explore mortality patterns associated with tropical cyclones

Understanding the circumstances and conditions surrounding disaster-attributed deaths may contribute to designing and implementing emergency preparedness and response programmes. This paper introduces a three-step cluster analysis of multiple binary variables to investigate mortality patterns related to tropical cyclones. It is designed to overcome the difficulties of performing cluster analysis in a disaster database that is composed in part of nominal variables and is unavoidably incomplete owing to missing information. The first step in the process codes all variables as binary data in order to accommodate the nominal variables. The second step calculates Spearman's rank correlation coefficients for pairs of variables. And the third step subjects the correlation coefficients to cluster analysis. Data related to 1,575 deaths attributed to tropical cyclones (also known as typhoons) that struck Taiwan between 2000 and 2015 are used to illustrate the method. The results yield two distinct groups of variables that are worthy of further exploration.

Impact of airflow obstruction on long-term mortality in patients with asthma in Japan

BACKGROUND

The long-term prognosis of asthma with airflow obstruction is poorly understood in Japan. The aim of this retrospective 26-year study was to investigate the long-term mortality risk of airflow obstruction in asthmatics.

METHODS

Using data from the Omuta City Air Pollution-related Health Damage Cohort Program, mortality risk ratios of airflow obstruction in Japanese Individuals were analyzed by Cox proportional hazards models. Airflow obstruction was considered to be present when the forced expiratory volume in 1 sec (FEV₁)/forced vital capacity ratio was <0.7 and FEV₁ predicted was <80% based on spirometry.

RESULTS

Among the 3146 victims with chronic respiratory diseases, 697 with adult asthma were selected. Median follow-up period was 26.3 (range 0.9-40.9) years. The airflow obstruction group (n = 193) showed significantly higher rates of mortality related to respiratory problems (risk ratio [95% confidence interval] 1.51 [1.86-1.93], P = 0.0017) and asthma attacks (1.86 [1.30-2.66], P = 0.0011) than the without airflow obstruction group (n = 504). Airflow obstruction was an independent risk factor for both respiratory-related (1.84 [1.36-2.49], P = 0.0001) and all-cause (1.44 [1.17-1.76], P = 0.0008) mortality after adjustment for age, sex, body mass index, and smoking status. More severe airflow obstruction was significantly associated with poorer prognosis.

CONCLUSIONS

This long-term cohort program revealed the impacts of asthma with airflow obstruction as an independent mortality risk. Findings suggest that intervention and prevention of airflow obstruction can reduce long-term mortality in patients with asthma.

Very low asthma death incidence among Finnish children from 1999 to 2015

BACKGROUND

The most recent reports concerning asthma fatalities in Finnish children are from 1998. Since that time, asthma care has improved and asthma-related hospitalizations have decreased. Yet, it is unknown whether pediatric asthma deaths have similarly decreased.

OBJECTIVE

To investigate the epidemiology of asthma deaths in the Finnish pediatric population from 1999 onward and to describe the details of fatal asthma exacerbations.

METHODS

We obtained copies of the death certificates from Statistics Finland of all Finnish children aged 0-19 years who died from asthma between 1999 and 2015. After analyzing the death certificates, the medical records of those with possible asthma death were evaluated in detail to confirm the diagnosis. Incidence rates (IR) of asthma deaths were estimated per 1 000 000 person-years by dividing the number of asthma deaths by the total number of person-years.

RESULTS

Between 1999-2015, there were 6845 deaths among 0-19 year-old children, of which 21 were possible asthma deaths. Based on patient records and pathological findings, we identified four convincing asthma deaths: aged 7 months, 1 year, 2.5 years, and 19 years. None had known allergies or regularly used inhaled corticosteroids. No pre-school or school-aged children died from asthma in Finland between 1999 and 2015. The cumulative incidence of pediatric asthma deaths was 0.19 per million person-years.

CONCLUSION

Four Finnish children died from asthma between 1999 and 2015. This corresponds to a total incidence of 0.19 per million person-years. No pre-school or school-aged children died from asthma in Finland during the study period.

Infer Cause of Death for Population Health Using Convolutional Neural Network

In biomedical data analysis, inferring the cause of death is a challenging and important task, which is useful for both public health reporting purposes, as well as improving patients' quality of care by identifying severer conditions. Causal inference, however, is notoriously difficult. Traditional causal inference mainly relies on analyzing data collected from experiment of specific design, which is expensive, and limited to a certain disease cohort, making the approach less generalizable. In our paper, we adopt a novel data-driven perspective to analyze and improve the death reporting process, to assist physicians identify the single underlying cause of death. To achieve this, we build state-of-the-art deep learning models, convolution neural network (CNN), and achieve around 75% accuracy in predicting the single underlying cause of death from a list of relevant medical conditions. We also provide interpretations for the black-box neural network models, so that death reporting physicians can apply the model with better understanding of the model.

Pharmacoepidemiological Study of Long-Acting β-agonist/Inhaled Corticosteroid Therapy and Asthma Mortality: Clinical Implications

RATIONALE

The increased risk of asthma mortality in association with long-acting β₂-agonist (LABA) monotherapy is well documented but the risk associated with LABA plus inhaled corticosteroid (ICS) therapy remains unclear.

OBJECTIVE

We assessed the feasibility of a large pharmacoepidemiological study to compare the effect of combined LABA + ICS therapy with non-LABA maintenance therapy on the risk of asthma mortality.

METHODS

This observational retrospective study used electronic data from ten US data partners to construct a cohort of patients with persistent asthma (defined as: four or more asthma maintenance medication dispensings in 12 months and a code diagnosis of asthma). Asthma deaths were determined by linking patient data with the National Death Index.

RESULTS

From 5,881,438 asthma patients, a cohort of 994,627 met the criteria for persistent asthma and provided 2.4 million person-years of follow-up. The total number of deaths was 278 with only three of these occurring after incident exposure to an asthma maintenance medication. The overall pooled asthma mortality rate, standardized by age and data partner, was 1.16 [95 % confidence interval (CI) 0.98-1.34] per 10,000 person-years; crude mortality rates (per 10,000 person-years) increased with age and were higher in female individuals (1.34; 95 % CI 1.15-1.55) than in male individuals (0.92; 95 % CI 0.74-1.12).

CONCLUSIONS

Despite a cohort size of almost 1 million asthma patients, the asthma mortality risk associated with combined LABA + ICS therapy could not be determined. This study showed that very few patients with persistent asthma have asthma-related deaths, and confirmed that those who die are more likely to be older and female.

The feasibility of using multiple databases to study rare outcomes: the potential effect of long-acting beta agonists with inhaled corticosteroid therapy on asthma mortality

PURPOSE

Long-acting beta agonists (LABAs) when used without concomitant inhaled corticosteroids (ICS) increase the risk of asthma-related deaths, but the effect on asthma-related death of LABA used in combination with ICS therapy is unknown. To address this question, we explored the feasibility of conducting an observational study using multiple US health care data sources.

METHODS

Retrospective cohort study to evaluate the likelihood of getting an upper 95% confidence limit ≤1.4 for the asthma mortality rate ratio and ≤0.40 per 10 000 person-years for the mortality rate difference, assuming no effect of new use of combined LABA + ICS (versus non-LABA maintenance therapy) on asthma mortality. Ten research institutions executed centrally distributed analytic code based on a standard protocol using an extracted (2000-2010) persistent asthma cohort (asthma diagnosis and ≥4 asthma medications in 12 months). Pooled results were analyzed by the coordinating center. Asthma deaths were ascertained by linkage with the National Death Index.

RESULTS

In a cohort of 994 627 persistent asthma patients (2.4 million person-years; 278 asthma deaths), probabilities of the upper 95% confidence limit for effect estimates being less than targeted values, assuming a null relation, were about 0.05. Modifications in cohort and exposure definitions increased exposed person-time and outcome events, but study size remained insufficient to attain study goals.

CONCLUSIONS

Even with 10 data sources and a 10-year study period, the rarity of asthma deaths among patients using certain medications made it infeasible to study the association between combined LABA + ICS and asthma mortality with our targeted level of study precision. Copyright © 2016 John Wiley & Sons, Ltd.

Fatal asthma; is it still an epidemic?

BACKGROUND

Asthma mortality has declined since the 1980s. Nevertheless the World Health Organization (WHO) identified asthma as responsible for 225.000 deaths worldwide in 2005, and 430.000 fatal cases are expected by 2030. Some unexpected and concentrated fatal asthma events all occurred between 2013 and 2015 in Veneto, a North Eastern region of Italy, which prompted a more in-depth investigation of characteristics and risk factors.

METHODS

A web search including key words related to fatal asthma in Italy between 2013 and 2015 has been performed. Concerning the cases that occurred in Veneto, subjects' clinical records have been evaluated and details about concomitant weather conditions, pollutants and pollen count have been collected.

RESULTS

Twenty-three cases of asthma deaths were found in Italy; 16 of them (69%) occurred in the Veneto Region. A prevalence of male and young age was observed. Most of patients were atopic, died in the night-time hours and during the weekends. The possible risk factors identified were the sensitization to alternaria, previous near fatal asthma attacks and the incorrect treatment of the disease. Weather condition did not appear to be related to the fatal exacerbations, whereas among the pollutants only ozone was detected over the accepted limits. Smoking habits, possible drug abuse and concomitant complementary therapies might be regarded as further risk factors.

DISCUSSION

Although not free from potential biases, our web search and further investigations highlight an increasing asthma mortality trend, similarly to what other observatories report. The analysis of available clinical data suggests that the lack of treatment more than a severe asthma phenotype characterizes the fatal events.

CONCLUSIONS

Asthma mortality still represents a critical issue in the management of the disease, particularly in youngsters. Once more the inadequate treatment and the lack of adherence seem to be not only related to the uncontrolled asthma but also to asthma mortality.

Are sleep disorders associated with increased mortality in asthma patients?

BACKGROUND

South Korea has experienced problems regarding poor management of symptoms of asthma patients and remarkable increases in sleep disorders. However, few studies have investigated these issues. We examined the relationship between sleep disorders and mortality in asthma patients to suggest effective alternatives from a novel perspective.

METHODS

We used data from the National Health Insurance Service (NHIS) National Sample Cohort 2004-2013, which included medical claims filed for 186,491 patients who were newly diagnosed with asthma during the study period. We performed survival analyses using a Cox proportional hazards model with time-dependent covariates to examine the relationship between sleep disorders and mortality in asthma patients.

RESULTS

There were 5179 (2.78%) patients who died during the study period. Sleep disorders in patients previously diagnosed with asthma were associated with a higher risk of mortality (hazard ratio [HR]: 1.451, 95% confidence interval [CI]: 1.253-1.681). In addition, significant interaction was found between sleep disorders and Charlson comorbidity index.

CONCLUSIONS

Our findings suggest that an increased prevalence of sleep disorders in asthma patients increases the risk of mortality. Considering the worsening status of asthma management and the rapid growth of sleep disorders in South Korea, clinicians and health policymakers should work to develop interventions to address these issues.

Asthma associated with chronic rhinosinusitis: a population-based study

BACKGROUND

Few studies have investigated the relationship between asthma and chronic rhinosinusitis (CRS). The present study investigated the association between asthma and the risk of CRS in a large national sample.

METHODS

Patients newly diagnosed with asthma (International Classification of Diseases, Ninth Revision [ICD-9], Clinical Modification code 493) between 2000 and 2008 were identified from the Taiwan National Health Insurance Research Database. The cases were compared with sex-, age-, residence-, and insurance premium-matched controls, and both groups were followed until the end of 2009 for incidences of CRS with or without nasal polyps (CRSwNP or CRSsNP, respectively). Competing risk-adjusted Cox regression analyses were performed after adjustment for sex, age, residence, insurance premium, steroid use, hyperlipidemia, diabetes, hypertension, coronary artery disease, Charlson comorbidity index score, and mortality. We also performed a case-control study to determine the association between asthma and CRS.

RESULTS

The cohort study analysis examined 81,462 patients with a mean ± standard deviation (SD) follow-up period of 5.8 ± 2.4 years. Asthma was an independent predictor of CRSsNP (hazard ratio = 2.58; 95% confidence interval [CI], 2.20 to 3.03; p < 0.001) in the fully adjusted models. In the case-control analysis, both CRSwNP and CRSsNP were associated with asthma in the fully adjusted models.

CONCLUSION

Asthma was associated with increased risks of CRSwNP and CRSsNP, independent of several potential confounding factors.

A single mouse monoclonal antibody, E58 modulates multiple IgE epitopes on group 1 cedar pollen allergens

We recently described a dominant role for conformational epitopes on the group 1 allergen of the mountain cedar (Juniperus ashei, Cupressaceae), Jun a 1, in pollen hypersensitivity in South Central U.S.A. Since these epitopes are surface exposed and are likely to be flexible, they may be susceptible to molecular or physical perturbations. This may make Jun a 1 a potential target for new forms of therapy for cedar pollinosis. Here, we describe a mouse monoclonal antibody, termed E58, which binds to the group 1 allergens of the cedar pollens from three highly populated regions of the world (central U.S.A., France and Japan). Upon binding to these allergens, E58 strongly reduces the binding of patient's IgE antibodies to these dominant allergens. This characteristic of E58, and potentially other similar antibodies, suggests an opportunity to develop preventative or therapeutic agents that may inhibit cedar pollen sensitization or prevent their allergic reactions.

Asthma: Hospitalization Trends and Predictors of In-Hospital Mortality and Hospitalization Costs in the USA (2001-2010)

BACKGROUND

In the last decade, the proportion of people with asthma in the USA grew by nearly 15%, with 479,300 hospitalizations and 1.9 million emergency department visits in 2009 alone. The primary objective of our study was to evaluate in-hospital outcomes in patients admitted with asthma exacerbation in terms of mortality, length of stay (LOS) and hospitalization costs.

METHODS

We queried the HCUP's Nationwide Inpatient Sample (NIS) between 2001 and 2010 using the ICD9-CM diagnosis code 493 for asthma (n = 760,418 patients). The NIS represents 20% of all hospitals in the USA. Multivariate logistic regression analysis was used to evaluate predictors of in-hospital mortality. LOS and hospitalization costs were also analyzed.

RESULTS

The overall LOS was 3.9 days and as high as 8.3 days in patients requiring mechanical ventilation. LOS has decreased in recent years, though it continues to be higher than in 2001. The hospitalization cost increased steadily over the study period. The overall in-hospital mortality was 1% and as high as 9.8% in patients requiring mechanical ventilation. Multivariate predictors of longer LOS, higher hospitalization costs and in-hospital mortality included increasing age and hospitalizations during the winter months. Private insurance was predictive of lower hospitalization costs and LOS as well as lower in-hospital mortality.

CONCLUSION

Asthma continues to account for significant in-hospital mortality and resource utilization, especially in mechanically ventilated patients. Age, admissions during winter months and the type of insurance are independent predictors of in-hospital outcomes.

Asthma deaths in a large provincial health system. A 10-year population-based study

RATIONALE

Individuals with asthma are more likely to die from chronic conditions than the general population. Measuring only mortality with asthma listed as the primary cause of death may lead to an underestimation of total asthma mortality.

OBJECTIVES

To examine mortality patterns in the asthma population over 10 years, including asthma as the primary cause of death (asthma-specific mortality) and asthma as a secondary, contributing cause of death (asthma-contributing mortality).

METHODS

Health administrative data from Ontario, Canada were used to identify mortality rates and cause of death in subjects 0 to 99 years of age. Mortality rates were calculated in the asthma and general population from 1999 to 2008. Total asthma mortality was estimated by adding rates of asthma-specific and asthma-contributing mortality for years 2003 to 2008.

MEASUREMENTS AND MAIN RESULTS

Asthma-specific mortality rates per 100,000 asthma population decreased by 54.4% from 13.6 in 1999 to 6.2 in 2008. In 2008, the asthma population had higher all-cause mortality compared with the general population (rate ratio, 1.3), asthma-specific mortality rates were 60% higher among those in the lowest compared with highest socioeconomic status, and total asthma mortality was fourfold higher than asthma-specific mortality alone (21.6 vs. 5.4 per 100,000).

CONCLUSIONS

All-cause mortality rates have decreased substantially over the past decade. Compared with the general population, the asthma population has higher all-cause mortality and is more likely to die from comorbid conditions. Total asthma mortality was fourfold higher than asthma-specific mortality, highlighting the importance of comprehensive measurement approaches that include asthma-specific and asthma-contributing mortality.

The national review of asthma deaths: what did we learn and what needs to change?

KEY POINTS

The 2014 UK National Review of Asthma Deaths identified potentially preventable factors in two-thirds of the medical records of cases scrutinised45% of people who died from asthma did not call for or receive medical assistance in their final fatal attackOverall asthma management, acute and chronic, in primary and secondary care was judged to be good in less than one-fifth of those who diedThere was a failure by doctors and nurses to identify and act on risk factors for asthma attacks and asthma deathThe rationale for diagnosing asthma was not evident in a considerable number of cases, and there were inaccuracies related to the completion of medical certificates of the cause of death in over half of the cases considered for the UK National Review of Asthma Deaths.

EDUCATIONAL AIMS

To increase awareness of some of the findings of the recent UK National Review of Asthma Deaths and previous similar studiesTo emphasise the need for accurate diagnosis of asthma, and of the requirements for completion of medical certificates of the cause of deathTo consider areas for improving asthma care and prevention of attacks and avoidable deaths.

SUMMARY

Despite the development and publication of evidence-based asthma guidelines nearly three decades ago, potentially preventable factors are repeatedly identified in studies of the care provided for patients who die from asthma. The UK National Review of Asthma Deaths (NRAD), a confidential enquiry, was no exception: major preventable factors were identified in two-thirds of asthma deaths. Most of these factors, such as inappropriate prescription and failure to provide patients with personal asthma action plans (PAAPs), could possibly have been prevented had asthma guidelines been implemented. NRAD involved in-depth scrutiny by clinicians of the asthma care for 276 people who were classified with asthma as the underlying cause of death in real-life. A striking finding was that a third of these patients did not actually die from asthma, and many had no recorded rationale for an asthma diagnosis. The apparent complacency with respect to asthma care, highlighted in NRAD, serves as a wake-up call for health professionals, patients and their carers to take asthma more seriously. Based on the NRAD evidence, the report made 19 recommendations for change. The author has selected six areas related to the NRAD findings for discussion and provides suggestions for change in the provision of asthma care. The six areas are: systems for provision and optimisation of asthma care, diagnosis, identifying risk, implementation of guidelines, improved patient education and self-management, and improved quality of completion of medical certificates of the cause of death.

A systematic review of validated methods to capture acute bronchospasm using administrative or claims data

PURPOSE

To identify and assess billing, procedural, or diagnosis code, or pharmacy claim-based algorithms used to identify acute bronchospasm in administrative and claims databases.

METHODS

We searched the MEDLINE database from 1991 to September 2012 using controlled vocabulary and key terms related to bronchospasm, wheeze and acute asthma. We also searched the reference lists of included studies. Two investigators independently assessed the full text of studies against pre-determined inclusion criteria. Two reviewers independently extracted data regarding participant and algorithm characteristics.

RESULTS

Our searches identified 677 citations of which 38 met our inclusion criteria. In these 38 studies, the most commonly used ICD-9 code was 493.x. Only 3 studies reported any validation methods for the identification of bronchospasm, wheeze or acute asthma in administrative and claims databases; all were among pediatric populations and only 2 offered any validation statistics. Some of the outcome definitions utilized were heterogeneous and included other disease based diagnoses, such as bronchiolitis and pneumonia, which are typically of an infectious etiology. One study offered the validation of algorithms utilizing Emergency Department triage chief complaint codes to diagnose acute asthma exacerbations with ICD-9 786.07 (wheezing) revealing the highest sensitivity (56%), specificity (97%), PPV (93.5%) and NPV (76%).

CONCLUSIONS

There is a paucity of studies reporting rigorous methods to validate algorithms for the identification of bronchospasm in administrative data. The scant validated data available are limited in their generalizability to broad-based populations.

Long-term dynamics of death rates of emphysema, asthma, and pneumonia and improving air quality

BACKGROUND

The respiratory tract is a major target of exposure to air pollutants, and respiratory diseases are associated with both short- and long-term exposures. We hypothesized that improved air quality in North Carolina was associated with reduced rates of death from respiratory diseases in local populations.

MATERIALS AND METHODS

We analyzed the trends of emphysema, asthma, and pneumonia mortality and changes of the levels of ozone, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and particulate matters (PM2.5 and PM10) using monthly data measurements from air-monitoring stations in North Carolina in 1993-2010. The log-linear model was used to evaluate associations between air-pollutant levels and age-adjusted death rates (per 100,000 of population) calculated for 5-year age-groups and for standard 2000 North Carolina population. The studied associations were adjusted by age group-specific smoking prevalence and seasonal fluctuations of disease-specific respiratory deaths.

RESULTS

Decline in emphysema deaths was associated with decreasing levels of SO2 and CO in the air, decline in asthma deaths-with lower SO2, CO, and PM10 levels, and decline in pneumonia deaths-with lower levels of SO2. Sensitivity analyses were performed to study potential effects of the change from International Classification of Diseases (ICD)-9 to ICD-10 codes, the effects of air pollutants on mortality during summer and winter, the impact of approach when only the underlying causes of deaths were used, and when mortality and air-quality data were analyzed on the county level. In each case, the results of sensitivity analyses demonstrated stability. The importance of analysis of pneumonia as an underlying cause of death was also highlighted.

CONCLUSION

Significant associations were observed between decreasing death rates of emphysema, asthma, and pneumonia and decreases in levels of ambient air pollutants in North Carolina.

Nationwide individual record linkage study showed poor agreement of causes of death and hospital diagnoses at individual level but reasonable agreement at population level

OBJECTIVES

To investigate to what extent underlying and multiple causes of death represent end-of-life morbidity in individuals and at population level.

STUDY DESIGN AND SETTING

Cause of death and national hospital data were individually linked for all deaths at the age of 50-84 years, in 2005 in the Netherlands (n = 86,987). The individual agreement of diseases registered as a diagnosis of discharge in the last 2 years of life and underlying and multiple causes of death recorded was assessed. Cause-of-death ranking was compared with ranking of hospital diagnoses.

RESULTS

The percentage of persons with a hospital diagnosis registered as the underlying cause of death was <30% for most diseases, except for cerebrovascular disease, chronic obstructive pulmonary disease and bronchiectasis, acute myocardial infarction (40-60%), and cancers (70-90%). Low Cohen's kappa values confirmed poor individual agreement between hospital diagnoses and underlying and secondary causes of death recorded. At population level, however, frequency rankings of underlying and multiple causes of death agreed reasonably well with frequency ranking of hospital diagnoses (Spearman ρ of 0.58-0.60 and 0.61-0.63).

CONCLUSION

Underlying and multiple causes of death poorly represent diseases present at the end of life in individuals but show reasonably well which diseases are most common at population level.

Asthma control, cost and race: results from a national survey

OBJECTIVE

Although interventions have been shown to alleviate symptoms in most patients suffering from asthma, only one-third of asthma patients have disease that is well-controlled. The purpose of this study is to investigate whether partly and uncontrolled asthmas are associated with increased costs for asthma-related healthcare utilization compared to well-controlled asthma and to determine whether these associations differed across racial groups.

METHODS

We classified respondents from the Asthma Insights and Management survey into those with well-, partly and uncontrolled asthma and compared utilization of healthcare services and costs among these groups, as well as between whites and non-whites.

RESULTS

Respondents categorized as having asthma that was not well-controlled reported lower income levels, higher rates of unemployment and more trouble paying for healthcare; similar results were found in analyses stratified by race. Patients whose asthma was partly or uncontrolled had greater use of asthma-related medications and medical services compared to patients whose asthma was well-controlled. Total unadjusted and adjusted costs were greater in patients whose asthma was classified as partly and uncontrolled. Similar results were found in analyses stratified on race. Across all levels of asthma control, non-whites had higher rates of utilization of emergency rooms and urgent care facilities and had greater rates of hospitalizations compared to whites.

CONCLUSIONS

Our findings indicate that patients with asthma that is not well-controlled utilized more healthcare resources and had greater medical costs, despite lacking of health insurance which may suggest less access to care.

A nationwide survey of the severity, comorbidity, and mortality of hospitalized patients with asthma in Taiwan

OBJECTIVE

To clarify the epidemiology of asthma admission in a nationwide survey, we analyze the characteristics of hospitalized patients in Taiwan.

METHODS

Data regarding asthma-associated hospitalizations were obtained from the National Health Insurance Research Database of Taiwan from January 2001 to December 2002. Patient characteristics in terms of severity, mortality, and cost were stratified by age, gender, and presence of comorbidities.

RESULTS

A total of 59,983 hospitalizations with International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 493.xx and asthma-related treatment were included in the current analysis. When stratified by age, the number and duration of hospitalizations were distributed in J-shape distribution, with the nadir located in the range of 8-18 years of age. The severity of asthma was found to increase with age (p < 0.001) and was more severe in men compared with women (p < 0.001). The severity of in-hospital patients was significantly greater in subjects with underlying respiratory disease compared to patients with other comorbidities, such as cardiovascular disease and infectious disease. The mortality rates of all hospitalized asthma patients and pediatric hospitalized asthma patients were 0.77% and 0.02%, respectively. The risk factor for mortality of asthma was older age and male gender in multiple regression.

CONCLUSION

The severity of asthma increased after 18 years of age. Increased comorbidities in elderly patients might contribute to asthma severity. The mortality rate was low in pediatric patients and significantly increased in males and the elderly. The above findings suggest that additional effort is required in the treatment of elderly and male asthmatic patients.

Role of comorbid conditions in asthma hospitalizations in the south of France

BACKGROUND

Reasons for asthma hospitalizations are dynamic and complex. Comorbid conditions are important contributors to most chronic diseases today. We aim to characterize and describe risk factors associated with hospitalizations due to asthma in the Languedoc-Roussillon region (France) in 2009.

METHODS

Programme de Médicalisation des Systèmes d'Information (PMSI) data records from 2009 were sorted using selected International Classification of Diseases (ICD10) codes eliciting three groups of asthma hospitalizations according to acute severity. All available data including demographics, comorbid conditions, past hospitalizations either related or unrelated to asthma, seasonality and distance to medical facilities were used to compare the subjects within the three groups.

RESULTS

One thousand two hundred and eighty-nine hospitalizations due to asthma exacerbation were found, concerning 1122 patients. We observed significant differences within the groups, using univariate analysis, concerning duration of hospitalizations (mean ± SD, 4.9 ± 5.9 days vs 6.4 ± 6.8 vs 15.8 ± 16.8, P < 0.001), deaths (percentage, 0.03% vs 1.50% vs 9.20%, P < 0.001) and numbers of comorbid conditions (0.80 ± 0.95 vs 0.75 ± 0.97 vs 1.74 ± 1.36, P < 0.001). Recurrent admissions for asthma during the period 2006-2008 were significantly more frequent in the more severe group (1.93 ± 3.91 vs 2.56 ± 4.47 vs 2.81 ± 3.97, P = 0.006). In the multivariate model, age and number of comorbid conditions were independently associated with severe hospitalizations and deaths.

CONCLUSIONS

Asthma hospitalizations can be appropriately assessed using PMSI coding databases. In this study, age and the presence of comorbid conditions are the major risk factors for asthma hospitalizations and deaths.

Asthma and lung cancer risk: a systematic investigation by the International Lung Cancer Consortium

Asthma has been hypothesized to be associated with lung cancer (LC) risk. We conducted a pooled analysis of 16 studies in the International Lung Cancer Consortium (ILCCO) to quantitatively assess this association and compared the results with 36 previously published studies. In total, information from 585 444 individuals was used. Study-specific measures were combined using random effects models. A meta-regression and subgroup meta-analyses were performed to identify sources of heterogeneity. The overall LC relative risk (RR) associated with asthma was 1.28 [95% confidence intervals (CIs) = 1.16-1.41] but with large heterogeneity (I(2) = 73%, P < 0.001) between studies. Among ILCCO studies, an increased risk was found for squamous cell (RR = 1.69, 95%, CI = 1.26-2.26) and for small-cell carcinoma (RR = 1.71, 95% CI = 0.99-2.95) but was weaker for adenocarcinoma (RR = 1.09, 95% CI = 0.88-1.36). The increased LC risk was strongest in the 2 years after asthma diagnosis (RR = 2.13, 95% CI = 1.09-4.17) but subjects diagnosed with asthma over 10 years prior had no or little increased LC risk (RR = 1.10, 95% CI = 0.94-1.30). Because the increased incidence of LC was chiefly observed in small cell and squamous cell lung carcinomas, primarily within 2 years of asthma diagnosis and because the association was weak among never smokers, we conclude that the association may not reflect a causal effect of asthma on the risk of LC.

Safe use of long-acting β-agonists: what have we learnt?

INTRODUCTION

Long-acting β-agonists (LABAs) added to inhaled corticosteroids (ICS) reduce symptoms, improve lung function and enhance overall asthma control. However, several studies have indicated an increased risk of asthma mortality and asthma-related serious adverse events and the FDA recently mandated restrictions to the use of LABAs in asthma.

AREAS COVERED

This review highlights the clinical studies on which safety analyses pertaining to salmeterol and formoterol have been based and then focuses on recent meta-analyses of safety outcomes with and without consideration of concomitant ICS.

EXPERT OPINION

The phenomenon of masking of inflammation by LABA if ICS dose is insufficient underscores the potential for confounding in determining real safety risks. Under-treatment with ICS and differential dosing of ICS in many trials are major factors driving the LABA safety concern. The FDA meta-analysis, when stratified for mandatory ICS use, found no significant increase in the composite outcome of asthma mortality, intubations and hospitalizations. Add-on therapy with LABA is effective and safe if the dose of ICS is adequate to treat airway inflammation. LABA and ICS given in a single device will negate the possibility of LABA monotherapy which is contraindicated. The FDA has recommended that LABAs be withdrawn when control is achieved with combination therapy but recent evidence suggests this may result in loss of symptom control.

Asthma mortality in Puerto Rico: 1980-2007

BACKGROUND

Asthma is a highly prevalent chronic disease. Prevalence and mortality are particularly high in Puerto Ricans living in the United States as compared with other populations.

OBJECTIVE

To determine asthma mortality rates in Puerto Rico (1980-2007) and to assess the sociodemographic variables that may be associated with these rates.

METHODS

Data were obtained from the Vital Statistics Office at the Puerto Rico Department of Health. Crude mortality rates (CMRs) and their 95% confidence intervals (95% CIs) were used to evaluate differences between age groups and across years. Mortality risk ratios (RRs) by sociodemographic variables were estimated using generalized lineal models with a Poisson link function to identify at-risk groups.

RESULTS

During the study period, there were 4232 deaths recorded with asthma as the cause of death. From 1980 to 1998, annual asthma mortality rates fluctuated between 3.32 and 6.56 deaths per 100,000 (mean 4.77), followed by a decline after implementation of the ICD-10 for reporting cause of death in 1999. Between 1999 and 2007, the mean asthma death rate declined to 3.01 (4.89 in 1999 to 2.02 in 2007). Overall, asthma mortality rates were between 1.77 and 4.0 times higher in Puerto Rico than in the United States. Throughout the whole study period, mortality rates were higher in older age groups. In addition, the adjusted regression model for asthma deaths showed that persons divorced or widowed, and persons with only elementary education had significantly higher risk of asthma mortality than their counterparts.

CONCLUSION

Asthma death rates were higher in Puerto Rico than in the United States general population. Although asthma mortality in Puerto Rico declined, rates continued to be significantly higher than those recorded in the United States. There was a progressive decline in asthma mortality rates after 1999 that may be explained by changes in reporting classification, increased use of corticosteroids, and improved asthma awareness. After controlling for possible confounding variables, age and elementary education were found to increase the risk of mortality due to asthma among Puerto Ricans.

Technical report--racial and ethnic disparities in the health and health care of children

OBJECTIVE

This technical report reviews and synthesizes the published literature on racial/ethnic disparities in children's health and health care.

METHODS

A systematic review of the literature was conducted for articles published between 1950 and March 2007. Inclusion criteria were peer-reviewed, original research articles in English on racial/ethnic disparities in the health and health care of US children. Search terms used included "child," "disparities," and the Index Medicus terms for each racial/ethnic minority group.

RESULTS

Of 781 articles initially reviewed, 111 met inclusion criteria and constituted the final database. Review of the literature revealed that racial/ethnic disparities in children's health and health care are quite extensive, pervasive, and persistent. Disparities were noted across the spectrum of health and health care, including in mortality rates, access to care and use of services, prevention and population health, health status, adolescent health, chronic diseases, special health care needs, quality of care, and organ transplantation. Mortality-rate disparities were noted for children in all 4 major US racial/ethnic minority groups, including substantially greater risks than white children of all-cause mortality; death from drowning, from acute lymphoblastic leukemia, and after congenital heart defect surgery; and an earlier median age at death for those with Down syndrome and congenital heart defects. Certain methodologic flaws were commonly observed among excluded studies, including failure to evaluate children separately from adults (22%), combining all nonwhite children into 1 group (9%), and failure to provide a white comparison group (8%). Among studies in the final database, 22% did not perform multivariable or stratified analyses to ensure that disparities persisted after adjustment for potential confounders.

CONCLUSIONS

Racial/ethnic disparities in children's health and health care are extensive, pervasive, and persistent, and occur across the spectrum of health and health care. Methodologic flaws were identified in how such disparities are sometimes documented and analyzed. Optimal health and health care for all children will require recognition of disparities as pervasive problems, methodologically sound disparities studies, and rigorous evaluation of disparities interventions.

Maternal bisphenol a exposure promotes the development of experimental asthma in mouse pups

BACKGROUND

We recently reported that various environmental estrogens induce mast cell degranulation and enhance IgE-mediated release of allergic mediators in vitro.

OBJECTIVES

We hypothesized that environmental estrogens would enhance allergic sensitization as well as bronchial inflammation and responsiveness. To test this hypothesis, we exposed fetal and neonatal mice to the common environmental estrogen bisphenol A (BPA) via maternal loading and assessed the pups' response to allergic sensitization and bronchial challenge.

METHODS

Female BALB/c mice received 10 microg/mL BPA in their drinking water from 1 week before impregnation to the end of the study. Neonatal mice were given a single 5 microg intraperitoneal dose of ovalbumin (OVA) with aluminum hydroxide on postnatal day 4 and 3% OVA by nebulization for 10 min on days 13, 14, and 15. Forty-eight hours after the last nebulization, we assessed serum IgE antibodies to OVA by enzyme-linked immunosorbent assay (ELISA) and airway inflammation and hyperresponsiveness by enumerating eosinophils in bronchoalveolar lavage fluid, whole-body barometric plethysmography, and a forced oscillation technique.

RESULTS

Neonates from BPA-exposed mothers responded to this "suboptimal" sensitization with higher serum IgE anti-OVA concentrations compared with those from unexposed mothers (p < 0.05), and eosinophilic inflammation in their airways was significantly greater. Airway responsiveness of the OVA-sensitized neonates from BPA-treated mothers was enhanced compared with those from unexposed mothers (p < 0.05).

CONCLUSIONS

Perinatal exposure to BPA enhances allergic sensitization and bronchial inflammation and responsiveness in a susceptible animal model of asthma.

Urban minority children with asthma: substantial morbidity, compromised quality and access to specialists, and the importance of poverty and specialty care

BACKGROUND

Asthma disproportionately affects minorities, but not enough is known about morbidity and specialist access in asthmatic minority children.

OBJECTIVE

To examine asthma morbidity and access to specialty care in urban minority children.

METHODS

A consecutive series was recruited in 2004-2007 of urban minority children 2 to 18 years old seen for asthma in four emergency departments (EDs) or admitted to a children's hospital. Outcomes assessed included asthma symptom and attack frequency; missed school and parental work; asthma ED visits and hospitalizations; severity of illness; and asthma specialty care.

RESULTS

Of 648 children assessed, 220 were eligible. The mean age was 7 years; 68% were poor, 83% had Medicaid, 84% were African-American, and 16% were Latino. Sixty-eight percent of children were not in excellent/very good health, 73% had persistent asthma (moderate/severe = 52%), and only 44% had asthma care plans. The mean number of asthma attacks in the past year was 12, and of monthly daytime and nighttime asthma symptoms, is 12 and 12, respectively. The mean annual number of asthma doctor visits was 6; of ED asthma visits, 3; hospitalizations, 1; missed school days, 7; and missed parent work days, 6. Eighty-three percent of children have no asthma specialist, and 62% use EDs as the usual asthma care source. Poor children were less likely than the non-poor to have asthma specialists (13 vs. 26%; p < 0.03). African-Americans were more likely than Latinos to use EDs for usual asthma care (68% vs. 44%; p < 0.01). In multivariable analyses, poverty was associated with greater odds and having an asthma care plan with lower odds of an asthma attack in the past year; poverty also was associated with half the odds of having an asthma specialist. African-American children were significantly more likely to report the ED as the usual source of asthma care, and having an asthma specialist and male gender were associated with greater odds of having an asthma care plan.

CONCLUSIONS

Urban minority children with asthma average 1 asthma symptom daily, 1 exacerbation monthly, and 7 missed school days, 6 missed parental work days, 3 ED visits, and 1 hospitalization yearly; most receive their usual asthma care in EDs and have no asthma care plan or asthma specialist. Urban minority asthmatic children need interventions to reduce morbidity and improve access to specialists and asthma care plans, especially among the poor and African-Americans.

Deaths with asthma in France, 2000-2005: a multiple-cause analysis

Mortality from asthma has decreased in many countries since the 1990s. Mortality statistics are usually based only on the underlying cause of death. The objectives of this study were to describe the characteristics of deaths and the trends in asthma-related mortality using multiple-cause analysis. Data were obtained from the French Centre of Epidemiology on Medical Causes of Death. Because ICD-10 was implemented in 2000, the analysis covers the period 2000-2005. In 2004-2005, asthma was the underlying cause of 42% of deaths with certificates mentioning asthma. The age-standardised rates of death from asthma decreased from 2000 through 2005 (-12% and -11%/year in the 1-44 and 45-64 age groups, respectively). The decline for all deaths with asthma was less pronounced (-9%/year in the 1-44 age group and -8%/year in the 45-64). Among adults aged 65 or older, the decrease in asthma-related mortality was higher in men (-12%/year for underlying cause, -9% for multiple-cause) than women (-5% and -3%, respectively). Since 2002, age-standardised rates of asthma-related mortality have been higher in women than men. In people aged 1-44 years, in-hospital deaths have declined between 2000 and 2005 while the proportion of non-hospital deaths increased from 53% to 67%. Regardless of the definition used, the age-standardised rate of asthma-related deaths decreased from 2000 to 2005, and the faster decline for underlying cause than for multiple-cause mortality argues for a real decline in mortality attributable to asthma. Using multiple cause-of-death analysis provides additional information for asthma mortality surveillance.

Acute exacerbations of asthma: epidemiology, biology and the exacerbation-prone phenotype

Asthma is a highly prevalent chronic respiratory disease affecting 300 million people world-wide. A significant fraction of the cost and morbidity of asthma derives from acute care for asthma exacerbations. In the United States alone, there are approximately 15 million outpatient visits, 2 million emergency room visits, and 500,000 hospitalizations each year for management of acute asthma. Common respiratory viruses, especially rhinoviruses, cause the majority of exacerbations in children and adults. Infection of airway epithelial cells with rhinovirus causes the release of pro-inflammatory cytokines and chemokines, as well as recruitment of inflammatory cells, particularly neutrophils, lymphocytes, and eosinophils. The host response to viral infection is likely to influence susceptibility to asthma exacerbation. Having had at least one exacerbation is an important risk factor for recurrent exacerbations suggesting an 'exacerbation-prone' subset of asthmatics. Factors underlying the 'exacerbation-prone' phenotype are incompletely understood but include extrinsic factors: cigarette smoking, medication non-compliance, psychosocial factors, and co-morbidities such as gastroesophageal reflux disease, rhinosinusitis, obesity, and intolerance to non-steroidal anti-inflammatory medications; as well as intrinsic factors such as deficient epithelial cell production of the anti-viral type I interferons (IFN-alpha and IFN-beta). A better understanding of the biologic mechanisms of host susceptibility to recurrent exacerbations will be important for developing more effective preventions and treatments aimed at reducing the significant cost and morbidity associated with this important global health problem.

The burden of sepsis-associated mortality in the United States from 1999 to 2005: an analysis of multiple-cause-of-death data

Introduction

Sepsis is the 10th leading cause of death in the United States. The National Center for Health Statistics' multiple-cause-of-death (MCOD) dataset is a large, publicly available, population-based source of information on disease burden in the United States. We have analysed MCOD data from 1999 to 2005 to investigate trends, assess disparities and provide population-based estimates of sepsis-associated mortality during this period.

Methods

Sepsis-associated deaths occurring in the United States from 1999 to 2005 were identified in MCOD data using International Classification of Disease, 10th Revision (ICD-10) codes. Population-based mortality rates were calculated using bridged-race population estimates from the National Center for Health Statistics. Comparisons across age, sex and racial/ethnic groups were achieved by calculating mortality rate ratios.

Results

From 1999 to 2005 there were 16,948,482 deaths in the United States. Of these, 1,017,616 were associated with sepsis (6.0% of all deaths). The age-adjusted rate of sepsis-associated mortality was 50.37 deaths per 100,000 (95% confidence interval (CI) = 50.28 to 50.47). There were significant disparities in sepsis-associated mortality in race/ethnicity and sex groups (P < 0.0001). After controlling for age, Asians were less likely than whites to experience sepsis-related death (rate ratio (RR) = 0.78, 95% CI = 0.77 to 0.78), while Blacks (RR = 2.24, 95% CI = 2.23 to 2.24), American Indians/Alaska Natives (RR = 1.24, 95% CI = 1.24 to 1.25) and Hispanics (RR = 1.14, 95% CI = 1.13 to 1.14) were more likely than whites to experience sepsis-related death. Men were at increased risk for sepsis-associated death in all race/ethnicity categories (RR = 1.27, 95% CI = 1.27 to 1.28), but the degree of increased susceptibility associated with being male differed among racial/ethnic groups (P < 0.0001). Although crude sepsis-associated mortality increased by 0.67% per year during the study period (P < 0.0001), the age-adjusted mortality rate decreased by 0.18% per year (P < 0.01).

Conclusions

The rapid rise in sepsis mortality seen in previous decades has slowed, but population ageing continues to drive the growth of sepsis-associated mortality in the United States. Disparities in sepsis-associated mortality mirror those previously reported for sepsis incidence. Sepsis in Asians, Hispanics and American Indian/Alaska Natives should be studied separately because aggregate measures may obscure important differences among these groups.

Epidemiology of asthma exacerbations

Exacerbations of asthma sufficient to require urgent medical intervention are often, but not always, associated with viral infection, especially rhinovirus, with significant interaction with allergen sensitization and exposure. Seasonal patterns of exacerbations are seen especially in children, and may be aggravated by lack of adequate maintenance anti-inflammatory drug treatment during the high-risk viral season most well described in the Northern Hemisphere after school return in September. Age and sex differences in the epidemiology of exacerbations remain less than fully explained, but hormonal influences are demonstrable. Frequent exacerbations may be an indication of greater severity of disease, significant comorbidities, or poor compliance with therapy. Recognizing risk factors for exacerbations and implementing appropriate long-term management strategies coupled with improved compliance should reduce morbidity and mortality associated with asthma exacerbations.

Analysis of glaucoma-related mortality in the United States using death certificate data

PURPOSE

Recent studies have reported a connection between glaucoma and decreased survival. To evaluate the underlying causes of glaucoma-related mortality, we searched vital records data for deaths citing glaucoma and reviewed the demographic variables and comorbidities contained on these records.

MATERIALS AND METHODS

Deaths including glaucoma, as either an underlying cause or a contributing cause of death, were selected from US multiple-cause-of-death data for the years 1990 to 2003 and combined with population data from the US Census Bureau to calculate mortality rates. Logistic regression was used to determine whether reporting of accidents and/or selected systemic disorders are associated with glaucoma on the death certificate.

RESULTS

Fifteen thousand two hundred twenty-eight glaucoma-related deaths (0.05%) were identified during the years under study. Black males had the highest glaucoma-related mortality rate with 9.4 deaths per 1,000,000 persons annually, whereas Hispanic females had the lowest mortality rate at 1.8 deaths per 1,000,000. After adjusting for age, sex, and race/ethnicity, positive associations were found between glaucoma and hypertension [Odds ratio (OR): 4.89; 95% confidence interval (CI)=4.73-5.05], diabetes (OR: 2.60; 95% CI=2.50-2.71), asthma (OR: 3.14; 95% CI=2.72-3.62), and accidents of all types (OR: 1.45; 95% CI=1.35-1.55).

CONCLUSIONS

Glaucoma is an important contributor to mortality for certain individuals. The disparities in mortality rates observed among race/ethnic strata may be attributed to differences in access to care as well as true differences in disease incidence and/or severity among racial groups. Despite limitations with the data, our findings suggest associations between glaucoma and a number of comorbid conditions. These associations should be explored in future studies and serve to guide strategies for disease management and prevention.

The Asthma Control and Communication Instrument: a clinical tool developed for ethnically diverse populations

BACKGROUND

Lower levels of quality asthma care among racially diverse populations might be due to inaccurate disease status assessments. The Asthma Control and Communication Instrument (ACCI) is a new tool that captures patient report of disease status during routine care.

OBJECTIVE

We sought to test the ACCI's psychometric properties in a racially diverse population.

METHODS

We performed a cross-sectional study. Subjects were recruited from specialist and generalist urban outpatient clinics. The ACCI and measures of asthma control, quality of life, lung function, and specialist rating of asthma status were collected. Four ACCI domains were separately validated: Acute Care, Bother, Control, and Direction. Principal component analysis, internal consistency, concurrent, discriminative, known-groups validity, and accuracy were evaluated.

RESULTS

Two hundred seventy asthmatic patients (77% female subjects, 55% black) participated. ACCI Control domain internal consistency was 0.80. ACCI Bother, Control, and Direction domains showed strong concurrent validity with asthma control and quality-of-life measures (all P < .001). ACCI Acute Care and Direction domains showed strong concurrent validity with individual validation items (all P < .001). The ACCI Control domain discriminated clinically important levels of disease status measured by asthma control, quality of life (both P < .001), and percent predicted peak expiratory flow rate (P = .005) and was associated with specialist rating of disease status (P < .001), confirming known-groups validity. The accuracy of the ACCI Control domain in classifying patients with uncontrolled asthma was very good (area under the curve, 0.851; 95% CI, 0.742-0.95870). Results were similar for both black and white subjects.

CONCLUSION

The ACCI is a promising clinical tool that measures asthma disease status during routine health care and is valid for use in both black and white populations.

Risk factors for death in adults with severe asthma

BACKGROUND

Mortality risk in adult asthma is poorly understood, especially the interplay among race, disease severity, and health care access.

OBJECTIVE

To examine mortality risk factors in adult asthma.

METHODS

In a prospective cohort study of 865 adults with severe asthma in a closed-panel managed care organization, we used structured interviews to evaluate baseline sociodemographics, asthma history, and health status. Patients were followed up until death or the end of the study (mean, 2 years). We used Cox proportional hazards regression to evaluate the impact of sociodemographics, cigarette smoking, and validated measures of perceived asthma control, physical health status, and severity of asthma on the risk of death.

RESULTS

We confirmed 123 deaths (mortality rate, 6.7 per 100 person-years). In an analysis adjusted for sociodemographics and tobacco history, higher severity-of-asthma scores (hazard ratio [HR], 1.11 per 0.5-SD increase in severity-of-asthma score; 95% confidence interval [CI], 1.01-1.23) and lower perceived asthma control scores (HR, 0.91 per 0.5-SD increase in perceived asthma control score; 95% CI, 0.83-0.99) were each associated with risk of all-cause mortality. In the same adjusted analysis, African American race was not associated with increased mortality risk relative to white race (HR, 0.64; 95% CI, 0.36-1.14).

CONCLUSIONS

In a large managed care organization in which access to care is unlikely to vary widely, greater severity-of-asthma scores and poorer perceived asthma control scores are each associated with increased mortality risk in adults with severe asthma, but African American patients are not at increased risk for death relative to white patients.

Asthma mortality among Swedish children and young adults, a 10-year study

BACKGROUND

Previous reports indicate that morbidity and mortality from asthma have increased during the past decades. Here, the mortality rate associated with asthma and possible risk factors in children and young adults in Sweden during the period 1994-2003 were evaluated.

METHODS

The medical profession was asked to report suspected cases of death from asthma in individuals 1-34 years of age. All death certificates containing relevant ICD codes were reviewed. Medical records and autopsy reports were assessed and telephone interviews with next-of-kin performed.

RESULTS

During the 10-year period 37 deaths due to asthma were identified. The median age at the time of death was 27 years and 6 of the deceased were younger than 15. The overall incidence of death from asthma decreased from 1.54 deaths per million in 1994 to 0.53 per million in 2003. Common risk factors were under-treatment (23/37), poor adherence to prescribed treatment (17/37) and adverse psychosocial situation (19/37). An alarming finding was that 11 of the 37 deaths were probably caused by food allergy and for 8 subjects death was associated with exposure to pet dander. The death certificates were found to contain inaccuracies with 30% of those for whom asthma was reported as the underlying cause having died from other causes.

CONCLUSION

Asthma mortality in children and young adults in Sweden decreased between 1994 and 2003. Food allergy and inadequate treatment were the major risk factors for such a death. Recognition and special care of patients with asthma who have shown signs of non-compliance, denial or severe food allergy must be encouraged.

An evaluation of the cost-effectiveness of omalizumab for the treatment of severe allergic asthma

Omalizumab is the first licensed anti-immunoglobulin (Ig) E antibody shown to be effective for treatment of allergic (IgE-mediated) asthma. Recent international guidelines recommend omalizumab as add-on treatment to fixed dose inhaled corticosteroid (ICS) and long-acting beta(2)-agonist (LABA) combination therapy. However, omalizumab is more expensive than other current asthma treatments and health and reimbursement authorities are increasingly demanding evidence of economic benefit to support pricing and formulary listing. The aims of this article are to (i) summarize data on the human and economic burden of severe asthma, (ii) summarize the efficacy data obtained for omalizumab in clinical trials in patients with inadequately controlled severe persistent allergic asthma despite high-dose ICS plus a LABA, and (iii) discuss the cost-effectiveness evidence published for omalizumab in this patient population. A wealth of evidence exists highlighting that the health, economic and societal burden of asthma is considerable and is highly skewed towards patients with severe asthma, particularly when asthma is inadequately controlled. Omalizumab is clinically beneficial in patients with severe persistent allergic asthma despite high-dose ICS plus a LABA, particularly in a subgroup of patients who respond to therapy. In patients who respond to therapy, the cost-effectiveness of omalizumab compares well with other biologic treatments for chronic illness.

Eliminating asthma disparities: a national workshop to set a working agenda

In February 2005, a national workshop was held in Chicago, IL, to address the problem of disparities in asthma. A multidisciplinary group of > 1,000 national experts reviewed key issues related to asthma health disparities; considered current research, clinical care, and policy related to this problem; and developed a set of recommendations to reduce these disparities. The themes addressed were genetics, indoor environment, outdoor environment, family/social function, behavioral health, health-care delivery, health-care communications, role of community, role of private insurance, role of safety net providers, and state and local policy.

Asthma in the elderly: mortality rate and associated risk factors for mortality

BACKGROUND

There is a distinct lack of information on the prognosis of asthma in the elderly.

METHODS

In order to compare mortality rates of elderly people with and without asthma and to identify mortality risk factors in those with asthma, 1,233 ambulatory patients aged > or = 65 years with a diagnosis of asthma (n = 210) or chronic nonrespiratory conditions (n = 1,023) were enrolled in a multicentric study. Patients underwent baseline spirometry and multidimensional assessment and were then followed up for a mean of 57.9 months (SD 16.9). We compared mortality rates in the two groups and identified predictors of death using multivariable survival analysis.

RESULTS

The 5-year mortality rate in people with asthma was 24.3%, compared to 16.3% in control subjects (p < 0.01), but asthma per se did not explain the excess risk of death. The main causes of death among people with and without asthma were cardiovascular diseases (36.4% and 21.3%, respectively), nonneoplastic lung diseases (28.8% vs 5.4%), and neoplasms (7.6% vs 22.6%). In people without asthma, death was associated with age, gender, smoking, cardiovascular diseases, worse performance on a 6-min walking test, cognitive impairment, depression, and worse respiratory function. In people with asthma, only the association between death and age, smoking, and depression was confirmed. At variance with control subjects, in asthmatics we found an inverse correlation between being overweight and death (hazard ratio [HR], 0.35; 95% confidence interval [CI], 0.13 to 0.94) and a trend toward a higher mortality rate in people with a body mass index < 22 kg/m(2) (HR, 2.21; 95% CI, 0.94 to 5.18).

CONCLUSIONS

Asthma in the elderly was associated with higher mortality rate, although this condition was not an independent risk factor. Causes of death and factors associated with death were somewhat different between people with and without asthma.

Factors associated with mortality after an asthma admission: a national United Kingdom database analysis

BACKGROUND

Lack of a United Kingdom (UK) fatal asthma registry has resulted in few recent analyses regarding patient characteristics, co-morbidities, and admission type in relation to mortality post an asthma admission. This study aims to report these factors in addition to season of event for the years 2000-2005 to provide data regarding asthma burden in the in-patient hospital setting.

METHODS

Data were analysed from the CHKS database collated from UK National Health Service data providing 70% of in-patient coverage in the UK. Patients with admissions under ICD-10 codes J45 "Asthma" and J46 "acute severe asthma" were included. Codes for associated co-morbidity at time of admission were identified, as well as month of admission and death, age, gender and length of stay.

RESULTS

The mortality rate over the 5-year period was 1063 patients from 250,043 asthma admissions (0.43%). Critical care mortality was far higher and an annual rate indicated that for every 100,000 admissions 2878 (95% CI 2091;3857) patients died. Respiratory infection, cardiovascular disease and diabetes were common co-morbidities for all admissions. December and January had the peak number of deaths post asthma admission which were nearly all in adults, death being rarer in children. Women and those over 45 years had the highest rate of death which may reflect asthma prevalence.

CONCLUSIONS

Co-morbid conditions experienced by older asthma patients may contribute to mortality post an asthma admission and greater understanding of risk factors contributing to fatality are required.