Patients with asthma experienced more COVID-19 hospitalization, mortality

Key takeaways:

• The cohort included 3,467 COVID-19 patients with asthma and 336,406 COVID-19 patients without asthma.
• Patients with asthma had an unadjusted odds ratio of 2.13 for hospitalization.

SAN DIEGO — Among patients hospitalized for COVID-19, those with asthma had much more severe outcomes than those who did not have asthma, according to a poster presented at the American Thoracic Society International Conference.

Previous studies have offered conflicting evidence about the impact of asthma on COVID-19 outcomes, Antony Jackson Arumairaj, MD, clinical assistant professor, Metropolitan Hospital Center, New York Medical College, and colleagues wrote.

“There were some clinical studies which showed that it actually was a protective factor. Some said it actually was a high-risk factor,” Arumairaj told Healio. “So, we decided to do a national patient sample analysis.”

The study included 339,873 adults hospitalized with COVID-19 reported by the National Inpatient Sample 2020, including 336,406 who did not have asthma (age, 63.2 years; 52.3% men; 50.8% white) and 3,467 who did (age, 54.6 years; 31.8% men; 43.1% white).

Among patients who did not have asthma, 33.9% were in the lowest national income quartile, followed by 27.1% in the second lowest, 22.1% in the second highest and 16.7% in the highest.

Results were similar for those who did have asthma, including 35.4% in the lowest quartile, 25.7% in the second lowest, 22.7% in the second highest and 16.6% in the highest.

Insurance coverage among patients who did not have asthma included Medicaid (53.2%), Medicare (15.1%), private (27.6%) and uninsured (3.9%). Percentages among those with asthma included 34.1% for Medicaid, 20.9% for Medicare, 41.2% for private and 3.7 for uninsured.

“There are a lot of people from the lowest national income quartile who have Medicaid insurance as their only insurance,” Arumairaj said.

Also, he said, patients who believe that they someday may need ICU care for their asthma tend to use private insurance, which is why it was the most common coverage among patients with asthma.

In the unadjusted analysis, patients with asthma had an odds ratio of 2.13 (95% CI, 2.05-2.2) for hospitalization. The adjusted analysis, which accounted for demographic and clinical risk factors including age, sex, race, national income quartile and insurance, found an odds ratio of 1.91 (95% CI, 1.85-1.99).

Mortality rates included 13.5% for those patients who did not have asthma and 7.45% for those who did (P < .001), but those with asthma had an odds ratio of 4.99 for mortality (P < .001).

“This was also statistically significant,” Arumairaj said.

Based on these findings, the researchers said that patients with asthma had hospitalization rates that were approximately twice as high and mortality rates that were about five times as high as those patients who did not have asthma.

Considering these findings, the researchers said that patients with asthma should get regular vaccinations for COVID-19. Also, they continued, those who are hospitalized for COVID-19 should be closely monitored with a low threshold for transfer to the ICU for multimodal management.

However, Arumairaj cautioned that these were preliminary results and that he and his team are continuing their analysis.

“You have to take into the picture the comorbid status,” he said.

The researchers also will examine results based on whether these patients were hospitalized in teaching or nonteaching hospitals and if they were in tertiary, rural or suburban hospitals.

“There are many other variables which will have to come into the picture,” Arumairaj said.

Exacerbations also will be examined, he said, since inhalers may have contributed to a protective effect, as other patients who were not having exacerbations or using inhalers would experience worse COVID-19 outcomes once infected.

“We have to do the final analysis before we can actually come to a conclusion,” Arumairaj said. “Once we have the final analysis, we’ll be able to get a much clearer picture.”