Worsening of asthma control after recovery from mild to moderate COVID-19 in patients from Hong Kong

BACKGROUND: While there are postulations that asthma is potentially associated with severe coronavirus disease 2019 (COVID-19), there has been conflicting results from studies on the impact mild-to-moderate COVID-19 on asthma control after recovery. METHODS: A case control study on the association between mild-to-moderate COVID-19 and asthma control post infection was conducted. The primary outcome was a reduction in Asthma Control Test (ACT) score by ≥ 3 points post-COVID infection. The secondary outcomes included the change in ACT score, the proportion of patient with ACT score who dropped to ≤ 15 on enrolment visit and the need for escalation of asthma maintenance therapy. RESULTS: Out of the total of 221 adult patients with asthma recruited, 111 had mild-to-moderate COVID-19 within 30 to 270 days prior to study enrolment. The adjusted odds ratio (aOR) for a reduction in ACT score by ≥ 3 points after COVID-19 was 3.105 (95% CI = 1.385–6.959, p = 0.006). The odds of escalation of asthma maintenance therapy by at least 1 Global Initiative for Asthma (GINA) step was 4.733 (95% CI = 1.151–19.467, p = 0.031) and asthma patient are more likely to become uncontrolled after COVID-19 [aOR = 5.509 (95% CI = 1.061–28.600, p = 0.042)]. CONCLUSION: Mild-to-moderate COVID-19 among asthma patients, upon recovery, was associated with worsening of asthma symptom, lower ACT score, a higher need for escalation of asthma maintenance therapy and more uncontrolled asthma.