Retrospective Review on Patients With Recurrent Asthmatic Attacks Requiring Hospitalizations

Study Overview
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Brief Summary
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Asthma is a common respiratory disease. around the world. Asthma exacerbation is one of the major sequelae and associated with various morbidity and mortality. A satisfactory asthma control can help to bring down the risk of exacerbation and hence hospitalization. However, the real-world evidence on the clinical factors that leads to multiple admissions, when compared with single admission, due to asthma exacerbation is scarce. This study aimed at evaluating the clinical characteristics of patients who had single and multiple hospitalizations for asthma exacerbations, and exploring the risk factors that predict multiple hospitalizations.

Detailed Description
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Asthma is a common respiratory disease worldwide and in Hong Kong. According to the estimation by the Center for Disease Control and Prevention in 2015, 7.6% adults in the United States have asthma. In Hong Kong, the prevalence of asthma was estimated to be 10.1% among 13 to 14 years old children and 5.8% in randomly selected Chinese elderly aged more than 70. The clinical characteristics varies in different age groups, with elderly asthmatics have higher rates of bronchial hyper-reactivity and more severe phenotypes, when comparing with younger patients. This is more important in an ageing population. Asthmatic exacerbation is not an uncommon complication and can be fatal. For those patients with near-fatal asthma exacerbation, ICU admission and mechanical ventilation may be necessary to prevent mortality. This is more common among poor controllers and adults. Asthma-related deaths may be reduced if risk factors are recognized and addressed early. Many predictors for exacerbation had been identified, both endogenous and exogenous, including high eosinophil count, upper airway diseases, gastroesophageal reflux, poor inhaler technique, medication non-compliance, guideline non-compliance. One of the most powerful predictors for future exacerbation in patients with severe or difficult-to-treat asthma is a recent severe asthma exacerbation. In addition, hospitalization for exacerbations requiring ICU care and mechanical ventilation are both predictors for near-fatal asthma. After the acute attack, its unfavourable impact continues and can lead to multiple sequelae. Exacerbation of asthma is associated with a more rapid decline in the post-bronchodilator forced expiratory volume in 1 second and worse quality of life. In addition, individuals with uncontrolled asthma had higher medical expenditures and decreased productivity, contributing to a greater economic burden when compared with individuals without asthma. In contrary, patients with controlled asthma had lower hospitalization rate, mortality rate and less decline in lung function. Many of these factors are potentially reversible. But, there is still a significant proportion of asthma patients experiencing recurrent exacerbation despite optimization of pharmacological treatment. A model of better asthma care may be established by improving the understanding on these risk factors, leading to less exacerbation events.

Official Title
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Retrospective Review on Patients With Recurrent Asthmatic Attacks Requiring Hospitalizations

Conditions
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Asthma

Intervention / Treatment
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* Other: Asthma exacerbation related hospitalization


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients with hospitalization for asthmatic exacerbation according to physician's clinical judgement Age greater than 18 years old Exclusion Criteria: - Inappropriate diagnosis of asthma exacerbation after evaluation

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Asthma group<br>Patients with asthma | Other: Asthma exacerbation related hospitalization<br>* Evaluate the difference between patients with single and multiple hospitalizations for asthma exacerbation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients who had hospitalization for asthma attack | Number of patients who had hospitalization for asthma attack | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Burden of comorbidity among subjects with recurrent hospital admission for asthma attack | Burden of comorbidity among subjects with recurrent hospital admission for asthma attack | 1 year | 
| Spirometric parameters (FEV1, FVC) among subjects with recurrent hospital admission for asthma attack | Spirometric parameters (FEV1, FVC) among subjects with recurrent hospital admission for asthma attack | 1 year | 
| Baseline blood eosinophil among subjects with recurrent hospital admission for asthma attack | Baseline blood eosinophil among subjects with recurrent hospital admission for asthma attack | 1 year | 
| Prevalence of asthma patients who had received phenotypic workup | Prevalence of asthma patients who had received phenotypic workup | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Asthma, Asthma exacerbation, Asthma hospitalization, Asthma control, Asthma care