Metabolic syndrome linked to greater COVID-19 severity

Individuals with metabolic syndrome who are hospitalized for COVID-19 may have a greater risk for more severe COVID-19 disease, including an elevated risk of in-hospital mortality, acute respiratory distress syndrome (ARDS), and intensive care unit (ICU) admission, a recent prospective study showed.

“Our study found that if you have high cholesterol, high blood pressure, mild obesity, and pre-diabetes or diabetes and are hospitalized with COVID-19, you have a one in four chance of developing ARDS, which is significant,” said study lead author Assistant Professor Joshua Denson from the Tulane University School of Medicine, New Orleans, Louisiana, US.

This multinational (26 countries) study was conducted using data from the Society of Critical Care Medicine Discovery Viral Respiratory Illness Universal Study. The study involved 29,040 adults (mean age 61.2 years, 45 percent female, 57.8 percent White) hospitalized for RT-PCR–confirmed COVID-19 between February 15, 2020 and February 18, 2021 with a completed discharge status. The participants were categorized according to presence* or absence of metabolic syndrome (5,069 and 23,971 individuals, respectively). Hypertension was the most common metabolic syndrome comorbidity (53.7 percent), while 33.5 and 49.3 percent had prediabetes or diabetes and obesity, respectively.

There was a greater incidence of in-hospital mortality among patients with metabolic syndrome than those without (control group; 20.2 percent vs 16.0 percent; adjusted odds ratio [adjOR], 1.19, 95 percent confidence interval [CI], 1.08–1.31; p<0.001). [JAMA Network Open 2021;4:e2140568]

Patients with metabolic syndrome were also at an increased risk of developing ARDS than those in the control group (20.1 percent vs 12.0 percent; adjOR, 1.36, 95 percent CI, 1.12–1.66) and were more likely to be admitted to the ICU (48.4 percent vs 35.9 percent; adjOR, 1.32, 95 percent CI, 1.14–1.53) and require invasive mechanical ventilation (28.2 percent vs 17.0 percent; adjOR, 1.45, 95 percent CI, 1.28–1.65; p<0.001).

Patients with metabolic syndrome also had a longer duration of hospitalization than the control group (median 8.0 vs 6.8 days) as well as a longer length of ICU stay (median 7.0 vs 6.4 days; p<0.001 for both).

“We also found that at every level of respiratory support, patients with metabolic syndrome experienced worse outcomes [including] increased non-invasive ventilation, or high-flow oxygen support, and increased supplemental oxygen use compared to patients without metabolic syndrome,” Denson pointed out.

The risk of ARDS among patients with metabolic syndrome increased in a stepwise manner with each additional comorbidity (one: 10.4 percent [p=0.83]; two: 15.3 percent [p<0.001]; three: 19.3 percent [p<0.001]; and four: 24.3 percent [p<0.001]).

Subgroup analyses showed that compared with a separate group of individuals without any metabolic syndrome comorbidities, patients with prediabetes or diabetes, hypertension, or dyslipidaemia were at an increased risk of ARDS. Patients with prediabetes or diabetes or hypertension had an elevated risk of in-hospital mortality. In contrast, obesity was tied to a reduced risk of ARDS or in-hospital mortality compared with those without any comorbidities.

While presence of metabolic syndrome at COVID-19 hospitalization was significantly more common in US than non-US hospitals (18.8 percent vs 8 percent), in-hospital mortality did not differ between the US and non-US cohorts (adjOR, 0.64).

“[O]ne hypothesis for why the US led the world in COVID-19 cases and deaths could be the high prevalence of metabolic syndrome in this population,” the researchers said.

“These findings will assist with efforts for creating national infrastructures, for identifying critical illness risk factors and testing novel/repurposed medications to help improve patient outcomes,” said senior author Assistant Professor Rahul Kashyap from Mayo Clinic, Rochester, Minnesota, US.