Diabetes mellitus and obesity risk factors for COVID-19 diagnosis in pregnancy: INTERCOVID study

Eskenazi B et al explored in the INTERCOVID study the association in pregnant women between a COVID-19 diagnosis and preexisting DM or high BMI and the diagnosis of gestational DM (GDM). Establishing the impact of comorbidities on the risk of infection in pregnant women can provide additional impetus for COVID-19 vaccination among those who remain hesitant.

INTERCOVID was a multinational study conducted between March 2020 and February 2021 in 43 institutions from 18 countries, enrolling 2184 pregnant women aged 18 years; a total of 2071 women were included in the analyses. For each woman diagnosed with COVID-19, 2 nondiagnosed women delivering or initiating antenatal care at the same institution were also enrolled. The main exposures were preexisting diabetes mellitus, high body mass index (overweight or obesity was defined as a body mass index 25 kg/m2 ), and gestational diabetes mellitus in pregnancy. The main outcome was a confirmed diagnosis of COVID-19 based on a real-time polymerase chain reaction test, antigen test, antibody test, radiological pulmonary findings, or 2 predefined COVID-19 symptoms at any time during pregnancy or delivery.

In addition, among women who were diagnosed with COVID-19, authors examined whether having gestational diabetes mellitus, diabetes mellitus, or high body mass index increased the risk of having symptomatic vs asymptomatic COVID-19.

COVID-19 was associated with preexisting diabetes mellitus, overweight or obesity and gestational diabetes mellitus. The gestational diabetes mellitus association was specifically among women requiring insulin, whether they were of normal weight or overweight or obese.

A somewhat stronger association with COVID-19 diagnosis was observed among women with preexisting diabetes mellitus, whether they were of normal weight or overweight or obese. When the sample was restricted to those with a real-time polymerase chain reaction test or an antigen test in the week before delivery or during the entire pregnancy, including missing variables using imputation or controlling for month of enrollment, the observed associations were comparable.

In the INTERCOVID multinational study of more than 2000 pregnant women from 18 countries, preexisting DM and higher BMI were each associated with a higher risk of being diagnosed with COVID-19, after controlling for other potential confounders. Although women with GDM overall were marginally at higher risk of COVID-19 diagnosis, authors did observe a significantly higher risk of COVID-19 diagnosis associated with GDM in people who use insulin; the strength of the association approached that for DM, regardless of a woman's BMI. High BMI, but not GDM or DM, was related to more symptomatic disease among those with COVID-19.

"Our findings suggested that DM and overweight or obesity are more prevalent in women diagnosed with COVID-19 in pregnancy than in women not diagnosed with COVID-19 in pregnancy, suggesting that these risk factors make infection more likely. Moreover, COVID-19 diagnosis was associated with GDM among women who were using insulin. This information can help guide decision making for those women who still maybe hesitant to receive COVID-19 vaccination."

Source: Eskenazi B, Rauch S, Iurlaro E, et al. Diabetes mellitus, maternal adiposity, and insulindependent gestational diabetes are associated with COVID-19 in pregnancy: the INTERCOVID study. Am J Obstet Gynecol 2022;227:74.e1-16.