Independent risk factors for death in patients admitted for asthma exacerbation in Taiwan

The independent risk factors for death in patients admitted for asthma exacerbation have not been thoroughly investigated. This study aimed to investigate these independent risk factors and the relationship between mortality and the prescription patterns of anti-asthmatic medications in patients admitted for asthma exacerbation. Using a nested case-control design, we identified 267 cases (death after asthma admission) and 1035 controls (survival after asthma admission) from the Taiwan National Health Insurance Research Database (NHIRD) from 2001 to 2010. Conditional logistic regressions were used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs). We identified the independent risk factors for death as the comorbidities of pneumonia (aOR 3.82, 95% CI 2.41-6.05), genitourinary disease (aOR 1.75, 95% CI 1.17-2.62), septicemia (aOR 4.26, 95% CI 2.61-6.94), diabetes mellitus (aOR 2.10, 95% CI 1.30-3.38), arrhythmia (aOR 2.00, 95% CI 1.14-3.50), and a history of asthmatic hospitalization (aOR 4.48, 95% CI 2.77-7.25). Moreover, the use of short-acting β₂-agonist (SABA) and the dosage of oral corticosteroids (OCSs) >70 mg prednisolone during previous hospitalization (all p < 0.05) and the dosage of OCSs ≥110 mg prednisolone/month (aOR 2.21, 95% CI 1.08-4.50) during outpatient treatment independently increased the risk of death. The inhaled corticosteroids (ICSs) ≥4 canisters/year (aOR 0.39, 95% CI 0.19-0.78) independently reduced the risk of death. Specific comorbidities, asthma severity, and prescription patterns of SABA, OCSs, and ICSs were independently associated with mortality in patients admitted for asthma exacerbation. These results can be utilized to help physicians identify asthmatic patients who are at a higher mortality risk and to refine the management of the condition.