Rates and correlates of relapse following ED discharge for acute asthma: a Canadian 20-site prospective cohort study

Asthma-related emergency admissions and associated healthcare resource use in Alberta, Canada

BACKGROUND

There is a lack of real-world research assessing asthma management following asthma-related emergency department (ED) discharges. The objective of this study was to characterise follow-up care, healthcare resource use (HCRU) and medical costs following ED admissions in Alberta, Canada.

METHODS

A retrospective cohort study was conducted on adults with asthma using longitudinal population-based administrative data from Alberta Health Services. Adult patients with asthma and ≥1 ED admission from 1 April 2015 to 31 March 2020 were included. ED admissions, outpatient visits, hospitalisations and asthma-specific medication use were measured in the 30 days before and up to 90 days after each asthma-related ED admission. Mean medical costs attributable to each type of HCRU were summarised. All outcomes were stratified by patient baseline disease severity.

RESULTS

Among 128 063 patients incurring a total of 20 142 asthma-related ED visits, a substantial rate of ED readmission was observed, with 10% resulting in readmissions within 7 days and 35% within 90 days. Rates increased with baseline asthma severity. Despite recommendations for patients to be followed up with an outpatient visit within 2-7 days of ED discharge, only 6% were followed up within 7 days. The mean total medical cost per patient was $C8143 in the 30 days prior to and $C5407 in the 30 days after an ED admission.

CONCLUSIONS

Despite recommendations regarding follow-up care for patients after asthma-related ED admissions, there are still low rates of outpatient follow-up visits and high ED readmission rates. New or improved multidimensional approaches must be integrated into follow-up care to optimise asthma control and prevent readmissions.

Sex Plays a Multifaceted Role in Asthma Pathogenesis

Sex is considered an important risk factor for asthma onset and exacerbation. The prevalence of asthma is higher in boys than in girls during childhood, which shows a reverse trend after puberty—it becomes higher in adult females than in adult males. In addition, asthma severity, characterized by the rate of hospitalization and relapse after discharge from the emergency department, is higher in female patients. Basic research indicates that female sex hormones enhance type 2 adaptive immune responses, and male sex hormones negatively regulate type 2 innate immune responses. However, whether hormone replacement therapy in postmenopausal women increases the risk of current asthma and asthma onset remains controversial in clinical settings. Recently, sex has also been shown to influence the pathophysiology of asthma in its relationship with genetic or other environmental factors, which modulate asthmatic immune responses in the airway mucosa. In this narrative review, we highlight the role of sex in the continuity of the asthmatic immune response from sensing allergens to Th2 cell activation based on our own data. In addition, we elucidate the interactive role of sex with genetic or environmental factors in asthma exacerbation in women.

Clinical guidelines on pediatric asthma exacerbation in emergency department, a narrative review

Asthma has been known as a prevalent chronic-type inflammatory disease in children, because of their narrower respiratory airways. The present study aimed to identify guidelines for children asthma treatments. Extensive research was conducted on biomedical and pharmacological bibliographic database PubMed, EMBASE, MEDLINE, LILACS database, global independent network of Cochrane, Science Direct and global health library of Global Index Medicus. A comprehensive literature review was carried out using the terms Pediatric Asthma, epidemiology, management, and related clinical guidelines published from 2000 to 2019. After the primary assessment, quick diagnosis, clinical practice guidelines are useful tools for proper management of pediatric Asthma. By setting proper guidelines for this particular population, a higher improvement in quality of management of of pediatric Asthma is expected. Given the differences between the recommendations arisen by BTS/SIGN and NICE guidelines, critical comparison of the evidence-base guidelines provide suggestions that have more in common than what might seems at the first glance. The analysis of the variations presented in the present article will assist clinicians to make accurate decisions regarding their patients.

Engaging patients and primary care providers in the design of novel opinion leader based interventions for acute asthma in the emergency department: a mixed methods study

BACKGROUND

Multifaceted interventions driven by the needs of patients and providers can help move evidence into practice more rapidly. This study engaged both patients and primary care providers (PCPs) to help design novel opinion leader (OL)-based interventions for patients with acute asthma seen in emergency departments (EDs).

METHODS

A mixed methods design was employed. In phase I, we invited convenience samples of patients with asthma presenting to the ED and PCPs to participate in a survey. Perceptions with respect to: a) an ideal OL-profile for asthma guidance; and b) content, style and delivery methods of OL-based interventions in acute asthma directed from the ED were collected. In phase II, we conducted focus groups to further explore preferences and expectations for such interventions with attention to barriers and facilitators for implementation.

RESULTS

Overall, 54 patients completed the survey; 39% preferred receiving guidance from a respirologist, 44% during their ED visit and 56% through individual discussions. In addition, 55% expressed interest in having PCP follow-up within a week of ED discharge. A respirologist was identified as the ideal OL-profile by 59% of the 39 responding PCPs. All expressed interest in receiving notification of their patients' ED presentation, most within a week and including diagnosis and ED/post ED-treatment. Personalized, guideline-based, recommendations were considered to be the ideal content by the majority; 39% requested this guidance through a pamphlet faxed to their offices. In the focus groups, patients and PCPs recognized the importance of health professional liaisons in transitions in care; patient anxiety and PCP time constraints were identified as potential barriers for ED-educational information uptake and proper post-ED follow-up, respectively.

CONCLUSIONS

Engaging patients and PCPs yielded actionable information to tailor OL-based multifaceted interventions for acute asthma in the ED. We identified potential facilitators for the implementation of such interventions (e.g., patient interaction with alternative health care professionals who could facilitate transitions in asthma care between the ED and the primary care setting), and for the provision of post discharge self-management education (e.g., consideration of the first week of ED discharge as a practical time frame for this intervention). Prioritization of identified barriers (e.g., lack of PCP involvement) could be addressed by the identification of potential early adopters in practice environments (e.g., clinicians with special interest in asthma).

Reasons and outcomes for patients receiving ICS/LABA agents prior to, and one month after, emergency department presentations for acute asthma

Objective: Asthma is a common emergency department (ED) presentation. This study examined factors associated with inhaled corticosteroids/long-acting beta-agonist (ICS/LABA) use; and management and outcomes before and after ED presentation. Methods: Secondary analysis of a prospective cohort study; adults treated for acute asthma in Canadian EDs underwent a structured interview before discharge and were followed-up four weeks later. Patients received oral corticosteroids (OCS) at discharge and, at physician discretion, most received ICS or ICS/LABA inhaled agents. Analyses focused on ICS/LABA vs "other" treatment groups at ED presentation. Results: Of 807 enrolled patients, 33% reported receiving ICS/LABA at ED presentation; 62% were female, median age was 31 years. Factors independently associated with ICS/LABA treatment prior to ED presentation were: having an asthma action plan; using an asthma diary/peak flow meter; influenza immunization; not using the ED as usual site for prescriptions; ever using OCS and currently using ICS. Patients were treated similarly in the ED and at discharge; however, relapse was higher in the ICS/LABA group, even after adjustment. Conclusion: One-third of patients presenting to the ED with acute asthma were already receiving ICS/LABA agents; this treatment was independently associated with preventive measures. While ICS/LABA management improves control of chronic asthma, patients using these agents who develop acute asthma reflect higher severity and increased risk of future relapse.

Intramuscular versus oral corticosteroids to reduce relapses following discharge from the emergency department for acute asthma

BACKGROUND

Acute asthma is a common cause of presentations to acute care centres, such as the emergency department (ED), and while the majority of patients can be discharged, relapse requiring additional medical care is common. Systemic corticosteroids are a major part in the treatment of moderate to severe acute asthma; however, there is no clear evidence regarding the most effective route of administration for improving outcomes in patients discharged from acute care.

OBJECTIVES

To examine the effectiveness and safety of a single dose of intramuscular (IM) corticosteroids provided prior to discharge compared to a short course of oral corticosteroids in the treatment of acute asthma patients discharged from an ED or equivalent acute care setting.

SEARCH METHODS

The Cochrane Airways Group conducted searches of the Cochrane Airways Group Register of Trials, most recently on 14 March 2018. In addition in April 2017 we completed an extensive search of nine electronic databases including Medline, Embase, EBM ALL, Global Health, International Pharmaceutical Abstracts, CINAHL, SCOPUS, Proquest Dissertations and Theses Global, and LILACS. Furthermore, we searched the grey literature to identify any additional studies.

SELECTION CRITERIA

We included randomized controlled trials or controlled clinical trials if they compared the effectiveness of intramuscular (IM) versus oral corticosteroids to treat paediatric or adult patients presenting with acute asthma to an ED or equivalent acute care setting. Two independent reviewers assessed study eligibility and study quality. We resolved disagreements via a third party and assessed risk of bias using the Cochrane 'Risk of bias' tool. We assessed the quality of the evidence using GRADE.

DATA COLLECTION AND ANALYSIS

For dichotomous outcomes, we calculated individual and pooled statistics as risk ratios (RRs) with 95% confidence intervals (CIs) using a random-effects model. We reported continuous outcomes using mean difference (MD) or standardised mean difference (SMD) with 95% CIs using a random-effects model. We reported heterogeneity using I² and Cochran Q statistics. We used standard procedures recommended by Cochrane.

MAIN RESULTS

Nine studies involving 804 participants (IM = 402 participants; oral = 402 participants) met our review inclusion criteria. Four studies enrolled children (n = 245 participants), while five studies enrolled adults (n = 559 participants). All of the studies recruited participants presenting to an ED, except one study which recruited participants attending a primary care clinic. All of the paediatric studies compared intramuscular (IM) dexamethasone to oral prednisone/prednisolone. In the adult studies, the IM corticosteroid provided ranged from methylprednisolone, betamethasone, dexamethasone, or triamcinolone, while the regimen of oral corticosteroids provided consisted of prednisone, methylprednisolone, or dexamethasone. Only five studies were placebo controlled. For the purposes of this review, we did not take corticosteroid dose equivalency into account in the analysis. The most common co-intervention provided to participants during the acute care visit included short-acting beta₂-agonists (SABA), methylxanthines, and ipratropium bromide. In some instances, some studies reported providing some participants with supplemental oral or IV corticosteroids during their stay in the ED. Co-interventions provided to participants at discharge consisted primarily of SABA, methylxanthine, long-acting beta₂-agonists (LABA), and ipratropium bromide. The risk of bias of the included studies ranged from unclear to high across various domains. The primary outcome of interest was relapse to additional care defined as an unscheduled visit to a health practitioner for worsening asthma symptoms, or requiring subsequent treatment with corticosteroids which may have occurred at any time point after discharge from the ED.We found intramuscular and oral corticosteroids to be similarly effective in reducing the risk for relapse (RR 0.94, 95% CI 0.72 to 1.24; 9 studies, 804 participants; I² = 0%; low-quality evidence). We found no subgroup differences in relapse rates between paediatric and adult participants (P = 0.71), relapse occurring within or after 10 days post-discharge (P = 0.22), or participants with mild/moderate or severe exacerbations (P = 0.35). While we found no statistical difference between participants receiving IM versus oral corticosteroids regarding the risk for adverse events (RR 0.83, 95% CI 0.64 to 1.07; 5 studies, 404 participants; I² = 0%; moderate-quality evidence), an estimated 50 fewer patients per 1000 receiving IM corticosteroids reported experiencing adverse events (95% from 106 fewer to 21 more). We found inconsistent reporting of specific adverse events across the studies. There were no differences in the frequency of specific adverse events including nausea and vomiting, pain, swelling, redness, insomnia, or personality changes. We did not seek additional adverse events data.Participants receiving IM corticosteroids or oral corticosteroids both reported decreases in peak expiratory flow (MD -7.78 L/min, 95% CI -38.83 L/min to 23.28 L/min; 4 studies, 272 participants; I² = 33%; moderate-quality evidence), similar symptom persistence (RR 0.41, 95% CI 0.14 to 1.20; 3 studies, 80 participants; I² = 44%; low-quality evidence), and 24-hour beta-agonist use (RR 0.54, 95% CI 0.21 to 1.37; 2 studies, 48 participants; I² = 0%; low-quality evidence).

AUTHORS' CONCLUSIONS

There is insufficient evidence to identify whether IM corticosteroids are more effective in reducing relapse compared to oral corticosteroids among children or adults discharged from an ED or equivalent acute care setting for acute asthma. While we found no statistical differences, patients receiving IM corticosteroids reported fewer adverse events. Additional studies comparing the effectiveness of IM versus oral corticosteroids could provide further evidence clarity. Furthermore, there is a need for studies comparing different IM corticosteroids (e.g. IM dexamethasone versus IM methylprednisone) and different oral corticosteroids (e.g. oral dexamethasone versus oral prednisone), with consideration for dosing and pharmacokinetic properties, to better identify the optimal IM or oral corticosteroid regimens to improve patient outcomes. Other factors, such as patient preference and potential issues with adherence, may dictate practitioner prescribing.

Sex-based differences in CD103+ dendritic cells promote female-predominant Th2 cytokine production during allergic asthma

BACKGROUND

Gender disparities in adult patients with asthma regarding its prevalence and severity are mainly due to enhanced type 2 T-helper (Th2) cytokine production in female patients compared to that in male patients. However, the pathways mediating this effect remain unclear.

OBJECTIVE

We aimed to determine the roles of two major subsets of dendritic cells (DCs) in females, specifically those displaying CD11b or CD103, during enhanced Th2 priming after allergen exposure, using an ovalbumin-induced asthma mouse model.

METHODS

Sex-based differences in the number of DCs at inflamed sites, costimulatory molecule expression on DCs, and the ability of DCs to differentiate naïve CD4⁺ T cells into Th2 population were evaluated after allergen exposure in asthmatic mice. In addition, we assessed the role of 17β-oestradiol in CD103⁺ DC function during Th2 priming in vitro.

RESULTS

The number of CD11b^high DCs and CD103⁺ DCs in the lung and bronchial lymph node (BLN) was increased to a greater extent in female mice than in male mice at 16 to 20 hours after ovalbumin (OVA) inhalation. In BLNs, CD86 and I-A/I-E expression levels and antigen uptake ability in CD103⁺ DCs, but not in CD11b^high DCs, were greater in female mice than in male mice. Furthermore, CD4⁺ T cells cultured with CD103⁺ DCs from female mice produced higher levels of interleukin (IL)-4, IL-5, and IL-13, compared with CD4⁺ T cells cultured with CD103⁺ DCs from male mice. The 17β-oestradiol-oriented enhancement of CD86 expression on CD103⁺ DCs after allergen exposure induced the enhanced IL-5 production from CD4⁺ T cells.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings suggest that with regard to asthma, enhanced Th2 cytokine production in females might be attributed to 17β-oestradiol-mediated Th2-oriented CD103⁺ DCs in the BLN.

Asthma exacerbations: risk factors for hospital readmissions

OBJECTIVE

The aim of our study is to analyse hospital readmissions due to asthma, as well as the factors associated with their increase.

STUDY DESIGN

We carried out a retrospective study including all admissions of patients over 18 years old due to exacerbation of asthma occurring in our hospital between the years 2000 and 2010.

METHODS

The data were gathered by two members of the research team, by reviewing the clinical records. The first hospital admission of each patient was included for this study. An early readmission (ER) was defined as that which occurred in the following 15 days after hospital discharge and late readmission (LR) to that occurring from 16 days after discharge.

RESULTS

This study included 2166 hospital admissions and 1316 patients, with a mean age of 62.6 years. Of the 1316 patients analysed, 36 (2.7%) had one ER and 313 (23.8%) one LR. The only factor independently associated with a higher probability of an ER was poor lung function. A higher probability of LR was associated with a greater severity of the asthma (OR: 17.8, for severe asthma versus intermittent asthma), to have had any hospital admission in the previous year (OR: 3.5) and the use of a combination of ICS-LABA as maintenance treatment.

CONCLUSIONS

About 25% of the patients in our area admitted to hospital due to asthma exacerbation had repeat episodes of hospitalisation.

Prioritizing Systemic Corticosteroid Treatments to Mitigate Relapse in Adults With Acute Asthma: A Systematic Review and Network Meta-analysis

OBJECTIVES

While systemic corticosteroids (SCS) are widely used to prevent relapse in adults with acute asthma discharged from the emergency department, the most effective route of administration is unclear. The objective of this review was to examine the effectiveness of SCS in adults and to identify the most effective route of SCS to preventing relapse.

METHODS

A search was conducted to identify randomized controlled trials comparing the effectiveness of intramuscular (IM) or oral (PO) short-course or long-course corticosteroids to prevent relapse in adults with acute asthma. Two independent reviewers judged study relevance, inclusion, and risk of bias. Pooled statistics were calculated as risk ratios (RR) and odds ratios (OR) with 95% confidence intervals (CI) and credibility intervals (CrI) using a random-effects model. A Bayesian network meta-analysis was performed for indirect comparisons of SCS to placebo. Probability of best (PB) analysis was reported for comparisons between the routes of administration.

RESULTS

Thirteen studies of moderate quality were included. Four studies compared SCS to placebo, in which SCS significantly reduced relapse (RR = 0.43; 95% CI = 0.25 to 0.74). In the network meta-analysis, a significant reduction in relapse within 10 days of discharge was found in adults receiving IM (OR = 0.21; 95% CrI = 0.05 to 0.73) and PO long-course (OR = 0.31; 95% CrI = 0.09 to 0.95) corticosteroids. Relapse rates between PO short-course corticosteroids and placebo were not statistically significantly different (OR = 0.37; 95% CrI = 0.04 to 3.38). PB analysis favored IM corticosteroids (62%) followed by PO short-course (20.3%) and PO long-course (14.1%) corticosteroids.

CONCLUSIONS

The network analysis identified IM corticosteroids and PO long-course corticosteroids as the most effective strategies to prevent relapse among adults with acute asthma, compared to PO short-course corticosteroids. The lack of significant findings with PO short-course corticosteroids is likely due to the paucity of research. Further comparative studies are required to determine the safety and effectiveness of briefer PO SCS treatment options in adults.

Factors associated with relapse in adult patients discharged from the emergency department following acute asthma: a systematic review

A significant proportion of patients discharged from the emergency department (ED) with asthma exacerbations will relapse within 4 weeks. This systematic review summarises the evidence regarding relapses and factors associated with relapse in adult patients discharged from EDs after being treated for acute asthma. Following a registered protocol, comprehensive literature searches were conducted. Studies tracking outcomes for adults after ED management and discharge were included if they involved adjusted analyses. Methodological quality was assessed using the Newcastle–Ottawa Scale (NOS) and the Risk of Bias (RoB) Tool. Results were summarised using medians and IQRs or mean and SD, as appropriate. 178 articles underwent full-text review and 10 studies, of various methodologies, involving 32 923 patients were included. The majority of the studies were of high quality according to NOS and RoB Tool. Relapse proportions were 8±3%, 12±4% and 14±6% at 1, 2 and 4 weeks, respectively. Female sex was the most commonly reported and statistically significant factor associated with an increased risk of relapse within 4 weeks of ED discharge for acute asthma. Other factors significantly associated with relapse were past healthcare usage and previous inhaled corticosteroids (ICS) usage. A median of 17% of patients who are discharged from the ED will relapse within the first 4 weeks. Factors such as female sex, past healthcare usage and ICS use at presentation were commonly and significantly associated with relapse occurrence. Identifying patients with these features could provide clinicians with guidance during their ED discharge decision-making.