Asthma exacerbations: risk factors for hospital readmissions

Clinical characteristics of obese, fixed airway obstruction, exacerbation-prone phenotype and comorbidities among severe asthma patients: a single-center study

BACKGROUND

Severe asthma places a large burden on patients and society. The characteristics of patients with severe asthma in the Chinese population remain unclear.

METHODS

A retrospective review was conducted in patients with severe asthma. Demographic and clinical data were collected. Patients were grouped according to phenotypes in terms of exacerbations, body mass index (BMI) and fixed airway obstruction (FAO) status, and the characteristics of different groups were compared. Comorbidities, factors that influence asthma phenotypes, were also analyzed in the study.

RESULTS

A total of 228 patients with severe asthma were included in our study. They were more likely to be overweight or obese. A total of 41.7% of the patients received GINA step 5 therapy, and 43.4% had a history of receiving regular or intermittent oral corticosteroids (OCS). Severe asthmatic patients with comorbidities were prone to have more asthma symptoms and decreased quality of life than patients without comorbidities. Patients with exacerbations were characterized by longer duration of asthma, poorer lung function, and worse asthma control. Overweight or obese patients tended to have more asthma symptoms, poorer lung function and more asthma-related comorbidities. Compared to patients without FAO, those in the FAO group were older, with longer duration of asthma and more exacerbations.

CONCLUSION

The existence of comorbidities in patients with severe asthma could result in more asthma symptoms and decreased quality of life. Patients with exacerbations or with overweight or obese phenotypes were characterized by poorer lung function and worse asthma control. Patients with FAO phenotype tended to have more exacerbations.

[A Study of the Prevalence of Asthma in the General Population in Spain]

Introduction

Asthma is a disease with high prevalence, which affects all age groups and generates high health and social care costs. Studies carried out in a number of populations show great variability in its prevalence, even in geographically close populations, with data suggesting a relevant influence of socio-economic factors. At present, we do not have reliable data on the prevalence of this disease in the adult population of Spain. The objectives of this study are to estimate the prevalence of asthma in the Spanish population for those aged 18-79, to describe the variability between autonomous communities, to estimate the prevalence of under and overdiagnosis, to analyse the prevalence of uncontrolled asthma and steroid-dependent asthma, to evaluate the health care cost, to identify the most frequent phenotypes and to establish a starting point to evaluate the temporal trend with subsequent studies.

Methods

A cross-sectional, two-stage study will be carried out, including patients from 50 catchment areas. The study will be carried out in 3 phases: 1) screening and confirmation in the clinical history, in which patients with a previously correctly established diagnosis of asthma will be identified; 2) diagnosis of asthma to evaluate patients without a confirmed or excluded diagnosis; 3) characterization of asthma, where the characteristics of the asthmatic patients will be analysed, identifying the most frequent phenotypes.

Discussion

It seems necessary and feasible to carry out an epidemiological study of asthma in Spain to identify the prevalence of asthma, to optimize healthcare planning, to characterize the most frequent phenotypes of the disease, and to evaluate inaccurate diagnoses.

Different clinical characteristics of current smokers and former smokers with asthma: a cross-sectional study of adult asthma patients in China

Smoking is a trigger for asthma, which has led to an increase in asthma incidence in China. In smokers, asthma management starts with smoking cessation. Data on predictors of smoking cessation in Chinese patients with asthma are scarce. The objective of this study was to find the differences in clinical characteristics between current smokers and former smokers with asthma in order to identify factors associated with smoking cessation. Eligible adults with diagnosed asthma and smoking from the hospital outpatient clinics (n = 2312) were enrolled and underwent a clinical evaluation, asthma control test (ACT), and pulmonary function test. Information on demographic and sociological data, lung function, laboratory tests, ACT and asthma control questionnaire (ACQ) scores was recorded. Patients were divided into a current smokers group and a former smokers group based on whether they had quit smoking. Logistic regression analysis was used to analyze the factors associated with smoking cessation. Of all patients with asthma, 34.6% were smokers and 65.4% were former smokers, and the mean age was 54.5 ± 11.5 years. Compared with current smokers, the former smokers were older, had longer duration of asthma, had higher ICS dose, had more partially controlled and uncontrolled asthma, had more pack-years, had smoked for longer, and had worse asthma control. The logistic regression model showed that smoking cessation was positively correlated with age, female sex, pack-years, years of smoking, partially controlled asthma, uncontrolled asthma, and body mass index (BMI), but was negatively correlated with ACT, FEV1, FEV1%predicted, and widowed status. More than 30% of asthma patients in the study were still smoking. Among those who quit smoking, many quit late, often not realizing they need to quit until they have significant breathing difficulties. The related factors of smoking cessation identified in this study indicate that there are still differences between continuing smokers and former smokers, and these factors should be focused on in asthma smoking cessation interventions to improve the prognosis of patients with asthma.

Clinical analysis of the "small plateau" sign on the flow-volume curve followed by deep learning automated recognition

BACKGROUND

Small plateau (SP) on the flow-volume curve was found in parts of patients with suspected asthma or upper airway abnormalities, but it lacks clear scientific proof. Therefore, we aimed to characterize its clinical features.

METHODS

We involved patients by reviewing the bronchoprovocation test (BPT) and bronchodilator test (BDT) completed between October 2017 and October 2020 to assess the characteristics of the sign. Patients who underwent laryngoscopy were assigned to perform spirometry to analyze the relationship of the sign and upper airway abnormalities. SP-Network was developed to recognition of the sign using flow-volume curves.

RESULTS

Of 13,661 BPTs and 8,168 BDTs completed, we labeled 2,123 (15.5%) and 219 (2.7%) patients with the sign, respectively. Among them, there were 1,782 (83.9%) with the negative-BPT and 194 (88.6%) with the negative-BDT. Patients with SP sign had higher median FVC and FEV₁% predicted (both P < .0001). Of 48 patients (16 with and 32 without the sign) who performed laryngoscopy and spirometry, the rate of laryngoscopy-diagnosis upper airway abnormalities in patients with the sign (63%) was higher than those without the sign (31%) (P = 0.038). SP-Network achieved an accuracy of 95.2% in the task of automatic recognition of the sign.

CONCLUSIONS

SP sign is featured on the flow-volume curve and recognized by the SP-Network model. Patients with the sign are less likely to have airway hyperresponsiveness, automatic visualizing of this sign is helpful for primary care centers where BPT cannot available.

Efficacy of mepolizumab in usual clinical practice and characteristics of responders

BACKGROUND

Severe eosinophilic asthma is a high-burden disease. Mepolizumab has been effective in several randomized clinical trials. However, such success might not be applicable to patients treated in usual clinical practice. The objectives of this article are to evaluate the efficacy of mepolizumab in severe uncontrolled eosinophilic asthma under usual clinical practice, and to determine characteristics associated with the response to this treatment.

METHODS

We have conducted a retrospective, multicentre study, including all adult patients with severe uncontrolled eosinophilic asthma in Galicia, Spain, on whom mepolizumab treatment was started before June 2020, at least 6 months before the time of inclusion, and had received at least one dose of the drug. Patient characteristics, clinical data, respiratory function and comorbidities were collected at baseline and at the 6-month-follow-up. Responders and super-responders were defined according to clinical response and requirement of systemic corticosteroids.

RESULTS

122 patients (mean age 58 years old) were included. In the follow-up treatment 6 months later, 75.4% of the patients were well-controlled, displaying a significant reduction in blood eosinophil counts (p < 0.001), hospital admissions and disease exacerbations (p < 0.001), and had their systemic glucocorticosteroid dose significantly reduced (p < 0.001). The inhaled corticosteroid dose was also lowered (p < 0.01) after 6 months of treatment. Around two-thirds had a clinically significant increase in FEV1, 95% of the patients were considered responders and 43% super-responders.

CONCLUSION

In routine clinical practice, mepolizumab is effective in patients with severe eosinophilic asthma and it has a good safety profile.

Characteristics of patients with frequent systemic corticosteroid bursts for asthma in real clinical practice: are there frequent "short bursts?"

OBJECTIVE

The data on intermittent systemic corticosteroid therapy for asthma exacerbation, clinically called a "short burst," is limited. This study aimed to investigate the characteristics of patients with frequent systemic corticosteroid bursts for asthma in real clinical practice.

METHODS

Consecutive patients who regularly visited our hospital for asthma treatment between January 2019 and December 2020 were reviewed. The number of systemic corticosteroid bursts during the past 1 year was collected, and those with frequent bursts (≥2 times/year) were defined as the Frequent group.

RESULTS

Data on 236 patients were analyzed. Among them, 5.5% (95% confidence interval 3.2-9.2%) were in the Frequent group. In the Frequent group, 23% of patients had no unplanned visits, and 38% experienced at least one corticosteroid burst without visiting a physician (self-medication). One-third of patients did not undertake high-dose inhaled corticosteroid treatment, and three-fourths of patients did not undertake long-acting muscarinic antagonist treatment. Low pulmonary function and increased blood eosinophils were independently associated with the Frequent group (adjusted odds ratio = 0.73, 95% confidence interval 0.55-0.99, P = 0.039, per 10% predicted increase in a forced expiratory volume in 1 s; adjusted odds ratio = 1.15, 95% confidence interval 1.02-1.29, P = 0.025, per 100/μL increase in blood eosinophils).

CONCLUSIONS

There was a certain rate of frequent corticosteroid bursts in real clinical practice. It is important to determine the actual condition, as some patients experienced "hidden" frequent bursts and have the option to reinforce the treatment.

Predicting the requiring intubation and invasive mechanical ventilation among asthmatic exacerbation-related hospitalizations

OBJECTIVE

To identify the predictors of requiring intubation and invasive mechanical ventilation (IMV) in asthmatic exacerbation (AE)-related hospitalizations.

METHODS

This study was conducted in southern Thailand between October 2016 and September 2018. The characteristics and clinical findings of patients admitted for AE requiring intubation and IMV were analyzed. The variables were evaluated by univariate and multivariate analysis to identify the independent predictors.

RESULTS

A total of 509 patients with a median age of 53 years were included in the study. Being female (60.2%), having no previous use of a controller (64.5%), having a history of smoking, and having a high level of white blood cell count (14,820 cells/mm³) were the significantly more common characteristics of the patients requiring mechanical ventilation. Univariate analysis showed that being male (OR = 1.96 95% CI, 1.22-3.13), having a history of 1-2 AEs in the past 12 months (OR = 3.27 95% CI, 1.75-6.12), and having an absolute eosinophil count ≥300 cells/mm³ (OR = 1.68 95% CI, 1.05-2.69) were associated with patients requiring IMV, whereas the patients who were taking a reliever (OR = 0.36 95% CI, 0.23-0.57) and controller (OR = 0.42 95% CI, 0.27-0.68) were associated with a decreased risk of requiring intubation and IMV. In multivariate analysis, only 1-2 AEs within the past 12 months (OR = 3.12, 95% CI, 1.19-8.21) was an independent predictor of requiring intubation and IMV in patients with AE-related hospitalization (p = 0.021).

CONCLUSIONS

This study found that a history of 1-2 AEs in the past 12 months was a strong independent predictor for the requirement of intubation and IMV in patients hospitalized for AE-related conditions.

Association of obesity with severity outcomes in hospitalized pediatric asthma exacerbations

INTRODUCTION

While there seems to be an association between obesity and asthma, the exact nature of the relationship remains unknown. It is unclear if there is increased severity of exacerbation for those that require hospitalization. We examine the association between obesity and severity outcomes such as hospital length of stay, intensive care admissions, and need for continuous albuterol or magnesium administration.

METHODS

Patients 4 to 17 years old admitted between 1/1/2012-1/1/2016 with asthma identified by discharge codes were reviewed. Obesity was defined as BMI ≥95%. Clinical data such as age, gender, family history of asthma, use of controller medication along with outcome data such as length of stay, ICU admission, use of continuous albuterol, and use of magnesium were collected. Binary outcomes were analyzed with multivariate logistic regression while length of stay was analyzed with negative binomial regression.

RESULTS

Overall, 995 patients met inclusion criteria. The median age was 7 years old with 170 (17%) patients categorized as obese. We find no difference in length of stay (IRR 0.99 [0.91, 1.09], p = 0.9), PICU admission (OR 0.72 [0.43, 1.21], p = 0.22), or magnesium administration (OR 1.34 [0.95, 1.88], p = 0.09) between obese and non-obese patients. There were increased odds of continuous albuterol use (OR 1.47 [1.02, 2.11]) for obese patients.

CONCLUSION

We find no association between obesity and outcomes of length of stay, ICU admission, or magnesium administration. While growing evidence links obesity with asthma, our study suggests it may not be associated with the severity of exacerbation.

Obesity Does Not Increase the Risk of Asthma Readmissions

The relationship between obesity and asthma exacerbations is still under debate. The aim of our work is to analyse the relationship between obesity and hospital re-admissions in asthmatics. A review was retrospectively performed on all hospital admissions of adult patients due to asthma exacerbation occurring in our hospital for 11 years. All those cases with asthma as the first diagnosis in the discharge report were included, or those with asthma as the second diagnosis provided when the first diagnosis was respiratory infection or respiratory failure. Only the first hospital admission of each patient was included in this study. The Odds Ratios of a higher incidence of early/late readmissions due to asthma exacerbation were calculated using a binary logistic regression, using the body mass index (BMI) as independent variable, adjusted for all the variables included in the study. The study included 809 patients with a mean age of 55.6 years, and 65.2% were female. The majority (71.4%) were obese or overweight. No significant relationship was observed in the univariate or multivariate analyses between overweight or obesity and the early or late hospital readmissions due to asthma. Therefore, obesity does not seem to be a determining factor in the risk of asthma exacerbations.

Investigation of the Effect of Asthma on Mortality and Morbidity After Coronary Artery Bypass Surgery

OBJECTIVES

No studies have been specifically conducted on asthma patients undergoing cardiac surgery for assessing mortality and morbidity. Distinct effects of cardiac surgery lead to negative effects on respiratory functions, putting patients with existing lung diseases under an increased risk. We aimed to investigate whether asthma patients are under higher risk for mortality and possible complications after coronary artery bypass graft (CABG) surgery than patients without asthma.

MATERIALS AND METHODS

The study included patients who underwent elective CABG surgery at our hospital between November 2014 and November 2015. Patients with a history of asthma were verified with physical examination and spirometric measurements by a single. The asthma group was compared with the controls in terms of mortality and morbidities.

RESULTS

Asthma patients were extubated later than control patients (p=0.028); however, prolonged intubation (longer than 24 h) frequency was not different (p>0.05). Asthma patients required longer stay in the intensive care unit (ICU) (p=0.003) than controls. The incidence of perioperative asthma exacerbations was significantly lower in patients in whom asthma was previously well-controlled. The incidence of postoperative sibilant rhonchi was lower in patients in whom asthma was under control than in those in whom asthma was partially controlled (p=0.020).

CONCLUSION

Asthma is associated with longer ICU stay and asthma-related pulmonary complications after CABG surgery. Preoperative evaluation of asthma patients scheduled for CABG surgery requires consideration of the control status of asthma. Studies with more controls are needed to provide further evidence on the topic.

Distinct asthma phenotypes with low maximal attainment of lung function on cluster analysis

OBJECTIVE

Asthma is a heterogeneous disease with varying clinical presentations, severity and ability to achieve asthma control. The present study aimed to characterize clinical phenotypes of asthma in an Indian cohort of subjects using a cluster analysis approach.

METHODS

Patients with confirmed asthma (N = 100) and at least 6-months of follow-up data, identified by retrospective chart review, were included in this study. Demographics, age at disease onset, disease duration, body mass index, serial spirometry and allergen sensitization were assessed. Asthma control was assessed prospectively using Global Initiative for Asthma and Asthma Control Test. R version 3.4.3 was used for statistical analysis. Ward's minimum-variance hierarchical clustering method was performed using an agglomerative (bottom-up) approach. To compare differences between clusters, analysis of variance using Kruskal-Wallis test (continuous variables) and chi-square test (categorical variables) was used.

RESULTS

Cluster analysis of 100 treatment-naive patients with asthma identified four clusters. Cluster 1, (N = 40), childhood onset of disease, normal body weight, equal gender distribution and achieved normal lung function. Cluster 2 (N = 16) included adolescent disease-onset, obese, majority males and had poor attainment of maximum lung functions. Cluster 3 (N = 20) were older, late-onset of disease, obese, majority male and had poor attainment of maximum lung function. Cluster 4 (N = 24) had adult-onset of disease, obese, predominantly female and achieved normal lung function.

CONCLUSIONS

In an Indian cohort of well-characterized patients with asthma, cluster analysis identified four distinct clinical phenotypes of asthma, two of which had poor attainment of maximum lung functions.

Predicting admissions for adult asthma exacerbations in North Texas

OBJECTIVES

The purpose of this study was to provide a picture of asthma disparities and the contributions of social and environmental factors to asthma exacerbations in the north central region of Texas, where intense, rapid development is a feature of contemporary life.

DESIGN AND SAMPLE

Cross-sectional analysis of data associated with 66 hospitals in the 8 counties containing and surrounding the Dallas/Fort Worth metropolitan area. Census blocks containing adult asthma patients admitted to emergency departments (ED) or inpatient units for asthma exacerbations in 2014.

MEASURES

Data for secondary analysis were collected from the Dallas Fort Worth Hospital Council Foundation.

RESULTS

Sex, family income, education, race, age of housing, speed, and traffic density on neighborhood roads affected asthma admissions. Proximity to urban drilling sites had only a small effect on admissions in this sample. Minorities were significantly more likely to obtain services in the ED than whites.

CONCLUSIONS

Attributes associated with poor and underserved patients predicted asthma exacerbations in the target region. These are vulnerable patients who can ill afford further erosion of health care insurance or additional environmental insults.

Association between blood eosinophil count and risk of readmission for patients with asthma: Historical cohort study

Background

Recent studies have demonstrated an association between high blood eosinophil counts and greater risk of asthma exacerbations. We sought to determine whether patients hospitalized for an asthma exacerbation were at greater risk of readmission if they had a high blood eosinophil count documented before the first hospitalization.

Methods

This historical cohort study drew on 2 years of medical record data (Clinical Practice Research Datalink with Hospital Episode Statistics linkage) of patients (aged ≥5 years) admitted to hospital in England for asthma, with recorded blood eosinophil count within 1 baseline year before admission. We analyzed the association between high blood eosinophil count (≥0.35x10⁹ cells/L) and readmission risk during 1 year of follow-up after hospital discharge, with adjustment for predefined, relevant confounders using forward selection.

Results

We identified 2,613 eligible patients with asthma-related admission, of median age 51 years (interquartile range, 36–69) and 76% women (1,997/2,613). Overall, 835/2,613 (32.0%) had a preadmission high blood eosinophil count. During the follow-up year, 130/2,613 patients (5.0%) were readmitted for asthma, including 55/835 (6.6%) with vs. 75/1,778 (4.2%) without high blood eosinophil count at baseline (adjusted hazard ratio [HR] 1.49; 95% CI 1.04–2.13, p = 0.029). The association was strongest in never-smokers (n = 1,296; HR 2.16, 95% CI 1.27–3.68, p = 0.005) and absent in current smokers (n = 547; HR 1.00, 95% CI 0.49–2.04, p = 0.997).

Conclusions

A high blood eosinophil count in the year before an asthma-related hospitalization is associated with increased risk of readmission within the following year. These findings suggest that patients with asthma and preadmission high blood eosinophil count require careful follow-up, with treatment optimization, after discharge.

Chronic Rhinitis Is a High-Risk Comorbidity for 30-Day Hospital Readmission of Patients with Asthma and Chronic Obstructive Pulmonary Disease

BACKGROUND

Early hospital readmissions for asthma and chronic obstructive pulmonary disease (COPD), measured as hospital readmission within 30 days from the last discharge, is a major economic burden to our health care system. The association of this measure with comorbid chronic rhinitis (CR) has not been investigated before despite significant clinical association between CR and asthma or COPD.

OBJECTIVE

To investigate the association of CR with the risk of asthma or COPD-related early hospital readmission rates.

METHODS

This retrospective cohort study was performed using the asthma- and COPD-related hospital encounter and patient comorbidity data between June 15, 2012, and July 19, 2017, from a large hospital care system in Cincinnati, Ohio. Patients (any sex, race or socioeconomic status, and of all ages) with a primary discharge diagnosis of asthma (n = 4754 patients, 10,111 encounters) and COPD (n = 2176 patients, 4748 encounters) based on International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes were included. Relevant comorbidities, including comorbid allergic rhinitis (AR) or nonallergic rhinitis (NAR), in such patients were identified using ICD-10-CM codes. The association between 30-day asthma or COPD-related hospital readmission (1670 such encounters for asthma and 736 for COPD) and comorbid CR in the affected patients were determined using Cox proportional hazards models. Multivariate-adjusted hazard ratios (HRs), adjusted for relevant patient comorbidities, compared 30-day asthma- and COPD-related readmissions of patients with CR with those patients without a CR diagnosis.

RESULTS

Analysis was performed on 4754 patients with asthma and 2176 patients with COPD. The median follow-up period (+interquartile range) for asthma was 980 (+760) days and for COPD was 553 (+827) days. The HRs for 30-day asthma- or COPD-related readmission rates were significantly higher in patients with AR (HR = 4.4 [3.9, 5.0] and 2.4 [1.7, 3.2], respectively) or NAR (HR = 3.7 [2.9, 4.9] and 2.6 [1.8, 3.7], respectively) compared with patients without rhinitis. For asthma, both AR and NAR had higher HRs compared with all other comorbidities analyzed. For COPD, both AR and NAR had HRs to the magnitude as obesity and hypertension.

CONCLUSIONS

Comorbid CR is significantly associated with 30-day asthma- and COPD-related readmissions. These findings are useful for guiding health care professionals to focus on outpatient management of both the upper and lower respiratory tracts to reduce early readmission of patients with asthma and COPD.

The MEGA Project: A Study of the Mechanisms Involved in the Genesis and Disease Course of Asthma. Asthma Cohort Creation and Long-Term Follow-Up

The general aim of this study is to create a cohort of asthma patients with varying grades of severity in order to gain greater insight into the mechanisms underlying the genesis and course of this disease. The specific objectives focus on various studies, including imaging, lung function, inflammation, and bronchial hyperresponsiveness, to determine the relevant events that characterize the asthma population, the long-term parameters that can determine changes in the severity of patients, and the treatments that influence disease progression. The study will also seek to identify the causes of exacerbations and how this affects the course of the disease. Patients will be contacted via the outpatient clinics of the 8 participating institutions under the auspices of the Spanish Respiratory Diseases Networking System (CIBER). In the inclusion visit, a standardized clinical history will be obtained, a clinical examination, including blood pressure, body mass index, complete respiratory function tests, and FENO will be performed, and the Asthma Control Test (ACT), Morisky-Green test, Asthma Quality of Life Questionnaire (Mini AQLQ), the Sino-Nasal Outcome Test 22 (SNOT-22), and the Hospital Anxiety and Depression scale (HADS) will be administered. A specific electronic database has been designed for data collection. Exhaled breath condensate, urine and blood samples will also be collected. Non-specific bronchial hyperresponsiveness testing with methacholine will be performed and an induced sputum sample will be collected at the beginning of the study and every 24 months. A skin prick test for airborne allergens and a chest CT will be performed at the beginning of the study and repeated every 5 years.