Asthma and COVID-19 Outcomes: A Prospective Study in a Large Health Care Delivery System.

"Disclosure Dr Lindsay K Finkas reports grants from The Permanente Medical Group, during the conduct of the study. The authors report no other conflicts of interest in this work."

"KPNC-DOR Delivery Science and Applied Research Program (DARE)."

"This prospective study utilized data collected using the electronic health record (EHR) and database registries across the Kaiser Permanente Northern California (KPNC) region. The KPNC provides comprehensive healthcare to approximately one-third of the population in the greater San Francisco and Sacramento metropolitan areas. The asthma cohort was identified using the KPNC Adult Asthma Registry on 03/01/2020, which includes patients 18–85 years old meeting at least one HEDIS criteria, namely:1) emergency department visits or hospitalization for asthma; 2) had four or more asthma prescriptions filled in a 12-month period; 3) four or more outpatient asthma visits and filled 2 asthma prescriptions in any 12 months; or 4) prescription of six rescue inhalers in any 12 months or 2 ambulatory corticosteroid treatment prescriptions. Patients with asthma were excluded if they had a prior diagnosis of COPD, interstitial lung disease (ILD), bronchiectasis, or KPNC membership of less than 3 months during the observation period. A consort diagram of the derivation of the asthma cohort is shown in . A matched cohort with no evidence of utilization for asthma (outpatient visits, hospitalization, or prescriptions for asthma) or any of the three respiratory conditions listed above was identified and matched 1:1 based on birthyear (± 1 year), sex, and race/ethnicity. An index date was assigned to each control corresponding to the asthma diagnosis date of the matched case, and controls were also required to have at least 3 months of follow-up. This study was approved by the KPNC Regional Institutional Review Board. All the data accessed complied with relevant data protection and privacy regulations. Figure 1Consort diagram of asthma cohort derivation."