Comparison of hospitalization outcomes for delivery and resource utilization between pregnant women with kidney transplants and chronic kidney disease in the United States

Background This study aimed to assess outcomes of delivery hospitalizations, including acute kidney injury (AKI), obstetric and fetal events, and resource utilization among pregnant women with kidney transplants compared to pregnant women with no known kidney disease and chronic kidney disease (CKD) stages 3-5. Method Hospitalizations for delivery in the US were identified using the enhanced delivery identification method in the National Inpatient Sample dataset from the years 2009 to 2014. Diagnoses of CKD stages 3-5, kidney transplantation, along with obstetric events, delivery methods, and fetal events were identified using ICD-9-CM diagnosis and procedure codes. Patients with no known kidney disease group were identified by excluding any diagnoses of CKD, end stage kidney disease and kidney transplant. Multivariable logistic regression accounting for the survey weights and matched regression was conducted to investigate the risk of maternal and fetal complications in women with kidney transplants, compared to women with no kidney transplants and no known kidney disease, and compared to women with CKD stages 3-5. Result A total of 5,408,215 hospitalizations resulting in deliveries were identified from 2009 to 2014, including 405 women with CKD stages 3-5, 295 women with functioning kidney transplants, and 5,405,499 women with no known kidney disease. Compared to pregnant women with no known kidney disease, pregnant kidney transplant recipients were at higher odds of hypertensive disorders of pregnancy (OR = 3.11, 95%CI [2.26, 4.28]), preeclampsia/eclampsia/HELLP syndrome (OR = 3.42, 95%CI [2.54, 4.60]), preterm delivery (OR = 2.46, 95%CI [1.75, 3.45]), fetal growth restriction (OR = 1.74, 95%CI [1.01, 3.00]), and AKI (OR = 10.46, 95%CI [5.33, 20.56]). There were no significant differences in rates of gestational diabetes or cesarean section. Pregnant women with kidney transplants had 1.30-times longer lengths of stay and 1.28-times higher costs of hospitalization. However, pregnant women with CKD stages 3-5 were at higher odds of AKI (OR = 5.29, 95%CI [2.41, 11.59]), preeclampsia/eclampsia/HELLP syndrome (OR = 1.72, 95%CI [1.07, 2.76]) and fetal deaths (OR = 3.20, 95%CI [1.06, 10.24]), and had 1.28-times longer hospital stays and 1.37-times higher costs of hospitalization compared to pregnant women with kidney transplant. Conclusion Pregnant women with kidney transplant were more likely to experience adverse events during delivery and had longer lengths of stay and higher total charges when compared to women with no known kidney disease. However, pregnant women with moderate to severe CKD were more likely to experience serious complications than kidney transplant recipients. This article is protected by copyright. All rights reserved.