Factors associated with asthma attack recurrence in Ecuadorian children: longitudinal study of potential impact of the COVID-19 pandemic lockdown.

BACKGROUND: The COVID-19 pandemic caused a major disruption in access to and use of health resources and facilities. There are limited longitudinal data from low-resource settings on the impact of pandemic mitigation strategies and medication use on asthma attacks in children. METHODS: We did a longitudinal study of risk factors for asthma attack recurrence among children aged 5-17 years presenting with an attack to emergency rooms in public hospitals in Ecuador. Children were followed for at least 12 months by monthly telemonitoring. Cox regression models for multiple recurrences were used to identify potential risk factors. RESULTS: 213 asthmatic children were recruited from May 2019 to March 2020 when recruitment was interrupted by a COVID-19 lockdown: 97% were followed for at least 12 months (median 419 days, IQRs 393-421 days). In multivariable analysis, the lockdown effect (adjusted HR 0.35, 95% CI 0.22 to 0.56, p<0.001) and use of inhaled corticosteroids (adjusted HR 0.64, 95% CI 0.43 to 0.93, p=0.020) were strongly protective against recurrence while short-acting β2 agonist use was associated with increased recurrence, particularly among children with a previous asthma diagnosis (interaction p=0.033). Other risk factors were household mould (adjusted HR 1.42, 95% CI 1.03 to 1.95, p=0.031) and number of prerecruitment emergency room visits (adjusted HR 1.05, 95% CI 1.00 to 1.11, p=0.040). CONCLUSION: Our data show in a population of asthmatic children from marginalised urban neighbourhoods in Ecuador, that use of inhaled corticosteroids was protective against asthma attack recurrence as were mitigation strategies implemented during the COVID-19 pandemic to reduce transmission of respiratory viruses.