Impacts of Comorbidities on Annual Incidence and Frequency of Asthma Exacerbation Hospitalisation: Data from CARN Study

Purpose: While asthma comorbidities are associated with higher health care utilisation, lower quality of life and poorer asthma control, the impact of asthma comorbidities on hospitalisation for asthma exacerbation (H-AX) remains less recognised. We aim to analyse the impact of asthma comorbidities on H-AX.Methods: Based on a national survey on asthma control and disease perception (CARN 2015 study), we analysed the impact of comorbidities on annual incidence and frequency of H-AX in China. Information on demographic characteristics, asthma comorbidities and annual incidence and frequency of H-AX were presented in this study. Results: Among 3875 ambulatory asthma patients, 75.9% (2941/3875) had comorbidities, and 26.4% (1017/3858) experienced H-AX during past year. After adjusting for confounding factors such as demographic data, smoking status and asthma control, COPD [OR=2.189, 95%CI (1.673, 2.863)] and coronary heart disease [OR=1.387, 95%CI (1.032, 1.864)] were associated with higher annual incidence, while allergic rhinitis [OR=0.692, 95%CI (0.588, 0.815)] was associated with lower annual incidence, of H-AX. In terms of frequency, allergic rhinitis [OR=1.630, 95%CI (1.214, 2.187)], COPD [OR=1.472, 95%CI (1.021, 2.122)] and anxiety [OR=2.609, 95%CI (1.051, 6.477)] showed statistically significant correlation with frequent H-AX.Conclusions: Comorbidities such as COPD, coronary heart disease and allergic rhinitis, may have an important role in the risk and/or frequency of annual hospitalisations due to asthma exacerbation. The goal of asthma control should rely on a multi-disciplinary treatment protocol but not merely on efforts of respiratory physicians.