Asthma, metabolic syndrome worsen COVID-19 outcomes

Key takeaways:

• Metabolic syndrome had the same negative effect on both asthma and control group patients.
• Asthma was not associated with an increased risk for hospital mortality.

Asthma increased the need for respiratory support in COVID-19 patients, whereas metabolic syndrome raised the risk for severe COVID-19, according to a study published in The Journal of Allergy and Clinical Immunology: In Practice.

“While most studies have indicated that asthma is not linked to severe COVID-19, some research suggests an increased risk in patients with non-allergic or severe asthma, a finding that could relate to the high burden of metabolic comorbidities in these individuals,” Marija Vukoja, MD, PhD, of the department of internal medicine, faculty of medicine, University of Novi Sad, Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia, told Healio. “In our study, we aimed to determine whether metabolic syndrome potentiates the risk of severe COVID-19 in asthma patients.”

Methods

This observational study used data from the global COVID-19 Discovery Viral Respiratory Illness Universal Study (VIRUS) registry including 164 hospitals in 23 countries from February 2020 through October 2021. All patients were aged 18 years or older and had to be hospitalized for COVID-19.

The cohort was divided into four groups: asthma, chronic pulmonary disease (CPD), asthma with CPD and a control group that had no respiratory illness. Metabolic syndrome was determined by patients having three or more specific WHO criteria, including prediabetes, history of diabetes, diabetes medication use, obesity, history of hypertension or hypertension medication use, and dyslipidemia.

The primary outcome of the study was hospital mortality, whereas secondary outcomes consisted of the need for supplemental oxygen; high-flow nasal cannula or noninvasive mechanical ventilation; invasive mechanical ventilation; the worst level of oxygen support needed while hospitalized; intensive care unit admission; and lengths of hospital stay.

Results

Among the 27,660 patients included in the study (median age, 63 years; 44% women), 1,734 (6%) had asthma, 2,773 (10%) had CPD, 575 (2%) had both asthma and CPD and 22,578 (82%) were controls with no respiratory illness.

Patients with asthma were younger (median age, 58 years vs. 62 years) and a larger proportion were female (61% vs. 42%) compared with the control group. They also had higher obesity rates (49% vs. 34%) and metabolic syndrome (24% vs. 18%).

In patients with asthma, the overall mortality rate was 13%. In patients with asthma with CPD, it was 21%. In CPD patients, it was 29%, and mortality was 17% in the control patients.

Having CPD was associated with an increase in hospital mortality when compared with the control group (P < .001). Asthma patients vs. controls did not have a greater risk for hospital death, and this was the same for patients with both asthma and CPD.

Asthma patients showed a need for more respiratory support with an increase in supplemental oxygen use (P = .02), high-flow nasal cannula or noninvasive mechanical ventilation (P = .04) and invasive mechanical ventilation (P = .003) when compared with the control group. Patients with CPD and those with both asthma and CPD also had an increased need for supplemental oxygen, high-flow nasal cannula or noninvasive mechanical ventilation, invasive mechanical ventilation and intensive care unit admission (P < .001 for all), as well as length of hospital stay (P < .001 and P = .03, respectively).

Patients with asthma were also more likely to have invasive mechanical ventilation or extracorporeal membrane oxygenation compared with the control group (14% vs. 11.4%) according to the five-category WHO ordinal scale.

“Although asthma was not linked to a higher risk of hospital mortality compared to controls without airway disease, it was associated with an increased need for respiratory support, including supplemental oxygen, high-flow nasal cannula, noninvasive ventilation, and invasive mechanical ventilation,” Vukoja said.

Having metabolic syndrome significantly increased the risk for death in both the asthma group (P = .02) and the control group (P < .001). It also heightened the risk for invasive mechanical ventilation in the asthma group and the control group (P < .001 for both).

“We observed a significant prevalence of metabolic dysfunction among hospitalized COVID-19 patients with asthma, which heightened the risk of severe COVID-19,” Vukoja said. “Metabolic syndrome was found to elevate the risk of severe COVID-19 in both asthma patients and controls, with a similar magnitude of effect.”

Vukoja further noted that the magnitude of the study provided a unique insight into the global outcomes of asthma on patients with COVID-19.

“Our study confirmed that asthma was not linked to an increased risk of hospital mortality,” she said. “Unlike other studies, we found a higher risk of requiring invasive mechanical ventilation in patients with asthma. Finally, this study is, to our knowledge, the first to report on how poor metabolic health affects outcomes in asthma patients with COVID-19.”

Hospitalized COVID-19 patients with asthma may require more respiratory support than those without asthma, according to Vukoja.

“Understanding the impact of metabolic syndrome in asthma patients with COVID-19 is crucial,” she said. “These findings could help physicians identify high-risk asthma patients and optimize both health care resources and patient management.”