Asthmatics who have their illness well under control have less severe Covid-19 outcomes than those with uncontrolled asthma, according to a large study.

The findings, published in The Journal of Allergy and Clinical Immunology: In Practice, suggest that asthma patients -- especially those who require clinical care -- should continue taking their asthma medications during the Covid-19 pandemic.

"Anyone with asthma should continue to work with their health care provider to ensure they are getting the best treatment for their asthma, which leads to better asthma control and decreases the likelihood of severe Covid-19 outcomes," said Zhanghua Chen, Assistant Professor of population and public health sciences at the Keck School of Medicine of the University of Southern California.

Researchers collected data on 61,338 Covid-19 patients using electronic medical records from Kaiser Permanente Southern California from March 1 to August 31, 2020.

Medical codes were used to determine if these patients had asthma or chronic obstructive pulmonary disease prior to their Covid-19 diagnosis. Researchers also separated the data further, with the "active" group accounting for any patients who had a clinical visit for asthma within the last 12 months and the "inactive" group accounting for those who had not.

Patients in the active asthma group had significantly higher odds of hospitalization, a need for intensive respiratory support and ICU admission within 30 days of Covid-19 diagnosis compared to those with no history of asthma or COPD.

Notably, researchers did not see a higher likelihood of mortality within 60 days for the active asthma group.

"This study went beyond examining asthma's impact on Covid-19 outcomes and instead focused on how Covid-19 outcomes might change for asthma patients depending on their level of asthma control," said Anny H Xiang of the Kaiser Permanente Southern California Department of Research and Evaluation.

"We also saw that even in patients with active asthma, if they were using asthma medications their odds of worsened Covid-19 outcomes decreased, which demonstrates just how important these medications are," Xiang said.