Potential Impact of Biologic Use on Asthma-Related Hospitalization: An Epidemiological Study in Hong Kong.

Abstract

Background: While the individual effects of biologics in asthma are well demonstrated, the potential impact of the use of biologics on overall asthma-related hospitalization at a population-based level has not been reported.

Methods: A territory-wide study conducted in Hong Kong, involving all adult patients with asthma managed in Hospital Authority. The primary outcome was the change in asthma-related hospitalization from 2014 to 2023, correlating with the number of biologic use among patients with asthma and adjusted for Air Quality Health Index and influenza case number.

Results: The weekly asthma-related hospitalization was 96 episodes at the start of the study period and 78 episodes at the end of the study period. There was a significant reduction of asthma-related hospitalization associated with biologic usage, giving the estimated risk ratio of 0.994 (95% CI = 0.991-0.996, p value < 0.05). The estimated break-point for the change in asthma-related hospitalization was at Week 169 (95% CI = 130.3-207.7), which was the week of 19/3/2017 to 25/3/2017. The slopes before and after the break-point were 0.022 and -0.191 with the difference in the two slope estimates being significant (p < 0.001) according to the Davies test. The significant difference in the slope before and after the break-point suggested that beyond Week 169, there was a trend of significant reduction in asthma-related hospitalization.

Conclusion: We observed a reduction in asthma-related hospitalizations throughout the study period with a potential temporal association with the increase in biologic prescription. While biologics provided benefits in individual level, the possible benefits in a population-based level could be related to a more comprehensive care in severe asthma patients from the introduction of biologics for severe asthma.