Background: Many patients with atopic diseases, including asthma, have sought complementary and alternative medicine and traditional Chinese medicine (TCM) treatments. But, limited clinical studies have yet examined TCM effects on medical utility in asthma patients. Aim: To assess the medical utility of TCM in patients with asthma. Design: Population-based retrospective cohort study. Methods: We performed a 13-year population-based retrospective cohort study. A total of 5235 asthma patients who were TCM users and 5235 propensity-score matched asthma patients who never used TCM were sampled from the Taiwan National Health Insurance Research Database from 2000 to 2012. We compared these two groups of patients to calculate their medical utility, including numbers of emergency visits and hospitalizations until 2013. Univariate analyses were performed using Chi-square tests for dichotomous variables and t-tests for continuous variables. Cox proportional hazard models were conducted to investigate the medical utility of asthma after TCM use. Results: Compared with non-TCM patients, TCM patients had a significantly decreased medical utility of asthma admission [adjusted odds ratio (OR) = 0.63; 95% confidence interval (CI): 0.46-0.85; P < 0.05], especially in patients who used TCM for >60 days. Asthma medical utility in asthma emergencies was significantly higher for male than for female patients (adjusted OR = 1.45; 95% CI: 1.08-1.96). The most frequently used TCMs for asthma control or cough treatment were antitussive agents. Conclusion: This population-based retrospective cohort study showed a significantly decreased medical utility of emergency visits and admissions in TCM patients, especially using TCM for >60 days.
