In a cohort of patients with comparable risk factors to those of the study population, the prior risk for preeclampsia was about 1 percent. The researchers found that after excluding cases diagnosed before SARS-CoV-2 infection, the observed rate of preeclampsia was higher than expected: 1.9, 2.2, 5.7, and 11.1 percent among asymptomatic patients, and those with mild, moderate, and severe disease, respectively; this monotonic relationship between COVID-19 severity and preeclampsia risk was statistically significant. Comparing the risk for preeclampsia between asymptomatic patients and patients with COVID-19 symptoms, the risk for preeclampsia was increased in association with severe COVID-19 (adjusted risk ratio, 4.9). Furthermore, compared with those with asymptomatic or mild disease, the risk was increased for those with moderate or severe COVID-19 (adjusted risk ratio, 3.3).
Jonathan Lai, M.D., from King’s College Hospital London, and colleagues examined the association between severity of SARS-CoV-2 infection and preeclampsia among 1,223 patients. Overall, 51 (4.2 percent) had preeclampsia; 21 were diagnosed before SARS-CoV-2 infection.
“We present evidence that the more severe the infection with SARS-CoV-2, the greater the risk of preeclampsia and preterm birth,” the authors write. “SARS-CoV-2 infection can lead to endothelial dysfunction, intravascular inflammation, proteinuria, activation of thrombin, and hypertension, which are all features of preeclampsia. Therefore, a causal relationship must be considered.”