Uric acid to creatinine ratio as a novel predictor of preeclampsia development and severity

Objective: Preeclampsia (PE) is the leading cause of maternal and fetal morbidity and mortality. PE presents with new-onset hypertension after 20 weeks of gestation that can progress rapidly leading to serious complications for both the mother and the fetus. Thus, it is of crucial importance early identifying women at high-risk for PE as early as during the first trimester of pregnancy, to implement the appropriate management and therapeutic strategies. In our study we aimed to assess the associations between serum uric acid to creatinine ratio (SUA/Cr), the development of PE and PE-related maternal and neonatal complications. Design and method: We searched for uric acid and creatine values in the medical records of 269 pregnant women who attended our Hypertensive Disorders in Pregnancy Clinic from December 2015 to December 2021. Two-hundreds and twelve women developed hypertensive disorders of pregnancy (HDP) and 57 had normotensive pregnancies. Of the 201 women with HDP, 112 were diagnosed with PE. After comparing baseline characteristics of the enrolled women, we performed logistic regression analysis models to assess the associations between SUA/Cr, development of PE, and PE-related maternal and neonatal complications. Results: Women who developed PE were more frequently nulliparous and had a higher rate of preterm delivery and maternal and neonatal complications, compared to women with HDP and healthy controls. Serum SUA/Cr was consistently higher in women with PE in all trimesters of pregnancy. Serum uric acid and creatinine alone were higher only during the third trimester in women with PE compared to women with HDP and healthy controls. Third trimester SUA/Cr was associated with an increased risk of developing PE (OR 1.29, CI 1.15 - 1.50, p = 0.001), of preterm birth (OR 1.23, CI 1.05 - 1.45, p = 0.011), and of a composite neonatal outcome (OR 1.33, CI 1.12 - 1.59, p = 0.001), after adjustment for age, BMI before pregnancy, nulliparity, hypertensive therapy, and acetylsalicylic acid therapy during pregnancy. Conclusions: In our study, women who develop PE had elevated SUA/Cr throughout all the trimesters. SUA/Cr at the third trimester of pregnancy was associated with an increased risk of PE development and neonatal complications.