New research finds high blood sugar levels to correlate with COVID-19 mortality, even in people with no history of diabetes. The findings suggest the need for early blood glucose screenings in people with SARS-CoV-2 infections.
Who is at risk of dying from COVID-19? Ongoing research has identified vulnerable populations — including people with immunocompromised states, people aged 65 years or older, and people with underlying health conditions. Yet it is still unclear why COVID-19 can also be deadly for people who are not in high-risk groups.
Because excess sugar in the blood is linked to type 2 diabetes, a major risk factor for severe COVID-19 and death, a team of researchers in Spain has investigated whether high blood sugar levels alone correlate with COVID-19-related mortality.
The researchers used a national registry to analyze data from 11,312 COVID-19 positive patients in 109 hospitals in Spain from March 1 to May 31, 2020. Patients were excluded from the study if they made repeated hospital visits or did not provide informed consent.
Registry information included, but was not limited to, treatments, laboratory test results, and symptoms. The average patient age was 67.06 years, and 57.1% were male.
The researchers considered the patients to have diabetes if there was a record of the diagnosis or evidence of diabetes medication use before hospital admission. Only 18.9% of patients in the study had diagnosed diabetes.
Blood sugar levels were taken upon hospital admission, and the team used this information to categorize the patients into three groups: normal, high, and very high blood sugar.
The researchers found that high blood sugar levels were associated with older men with a history of diabetes, hypertension, or another health condition. The team also observed elevated levels of inflammation markers more frequently in patients with high blood sugar levels.
One of the most prominent findings was that as blood sugar levels increased, the risk of death from COVID-19 also rose. This association was not affected by a history of diabetes.
Of the 11,312 patients included in the study, 2,289 — or 20.2% — died of COVID-19. Among this group, 41.1% had very high blood sugar levels, while 15.7% had normal levels.
Patients with very high blood sugar levels were admitted to hospitals for slightly longer than those with normal levels. They also required more intensive care unit attendance and more invasive or noninvasive ventilation.