A territory-wide study on the factors associated with recurrent asthma exacerbations requiring hospitalization in Hong Kong

The burden of systemic corticosteroid use in asthma management in Asia

For most patients, asthma can be effectively managed using inhaled medications. However, patients who have severe and/or uncontrolled asthma, or who experience exacerbations, may require systemic corticosteroids (SCSs) to maintain asthma control. Although SCS are highly effective in this regard, even modest exposure to these medications can increase the risk for long-term, adverse health outcomes, such as type 2 diabetes, renal impairment, cardiovascular disease and overall mortality. Clinical and real-world data from studies investigating asthma severity, control and treatment practices around the globe have suggested that SCS are overused in asthma management, adding to the already substantial healthcare burden experienced by patients. Throughout Asia, although data on asthma severity, control and SCS usage are limited and vary widely among countries, available data strongly suggest a pattern of overuse consistent with the broader global trend. Coordinated changes at the patient, provider, institutional and policy levels, such as increasing disease awareness, promoting better adherence to treatment guidelines and increasing availability of safe and effective alternatives to SCS, are likely necessary to reduce the SCS burden for patients with asthma in Asia.

Recurrent events analysis with piece-wise exponential additive mixed models

Recurrent events analysis plays an important role in many applications, including the study of chronic diseases or recurrence of infections. Historically, many models for recurrent events have been variants of the Cox model. In this article we introduce and describe the application of the piece-wise exponential Additive Mixed Model (PAMM) for recurrent events analysis and illustrate how PAMMs can be used to flexibly model the dependencies in recurrent events data. Simulations confirm that PAMMs provide unbiased estimates as well as equivalence to the Cox model when proportional hazards are assumed. Applications to recurrence of staphylococcus aureus and malaria in children illustrate the estimation of seasonality, bivariate non-linear effects, multiple timescales and relaxation of the proportional hazards assumption via time-varying effects. The R package pammtools is extended to facilitate estimation and visualization of PAMMs for recurrent events data.

A territory-wide study on the factors associated with recurrent asthma exacerbations requiring hospitalization in Hong Kong

Background

The real‐world relationships between the demographic and clinical characteristics of asthma patients, their prehospitalization management and the frequency of hospitalization due to asthma exacerbation is poorly established.

Objective

To determine the risk factors of recurrent asthma exacerbations requiring hospitalizations and evaluate the standard of baseline asthma care.

Methods

A territory‐wide, multicentre retrospective study in Hong Kong was performed. Medical records of patients aged ≥18 years admitted to 11 acute general hospitals from January 1 to December 31, 2016 for asthma exacerbations were reviewed.

Results

There were 2280 patients with 3154 admissions (36.7% male, median age 66.0 [interquartile range: 48.0–81.0] years, 519 had ≥2 admissions). Among them, 1830 (80.3%) had at least one asthma‐associated comorbidity, 1060 (46.5%) and 885 (38.9%) of patients had Accident and Emergency Department (AED) attendance and hospitalization in the preceding year, respectively. Patients with advancing age (incidence rate ratio [IRR]: 1.003 for every year increment), a history of AED visits or hospitalization (IRR: 1.018 and 1.070 for every additional episode, respectively) for asthma exacerbation in the preceding year, the presence of neuropsychiatric (IRR: 1.142) and gastrointestinal (IRR: 1.154) comorbidities were risk factors for an increasing number of admissions for asthma exacerbation. For patients with ≥2 admissions, 17.1% were not prescribed inhaled corticosteroid and only 44.6% had spirometry checked before the index admission. Asthma phenotyping was often incomplete, as assessment of atopy (total serum immunoglobulin E level and senitization to aeroallergens) was only performed in 30 (5.8%) patients with ≥2 admissions.

Conclusions and Clinical Relevance

Improving asthma care, especially in elderly patients with a prior history of urgent healthcare utilization and comorbidities, may help reduce healthcare burden. Suboptimal management before the index admission was common in patients hospitalized for asthma exacerbations. Early identification of patients at risk and enhancement of baseline asthma management may help to prevent recurrent asthma exacerbation and subsequent hospitalization.