Diabetic Ketoacidosis and Adverse Outcomes Among Pregnant Individuals With Pregestational Diabetes in the United States, 2010–2020

OBJECTIVE: To assess the frequency of, risk factors for, and adverse outcomes associated with diabetic ketoacidosis (DKA) at delivery hospitalization among individuals with pregestational diabetes (type 1 and 2 diabetes mellitus) and secondarily to evaluate the frequency of and risk factors for antepartum and postpartum hospitalizations for DKA. METHODS: We conducted a serial, cross-sectional study using the Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project Nationwide Readmissions Database from 2010 to 2020 of pregnant individuals with pregestational diabetes hospitalized for delivery. The exposures were 1) sociodemographic and clinical risk factors for DKA and 2) DKA. The outcomes were DKA at delivery hospitalization, maternal morbidity (nontransfusion severe maternal morbidity (SMM), critical care procedures, cardiac complications, acute renal failure, and transfusion), and adverse pregnancy outcomes (preterm birth, hypertensive disorders of pregnancy, and cesarean delivery) and secondarily DKA at antepartum and postpartum hospitalizations. RESULTS: Of 392,796 deliveries in individuals with pregestational diabetes (27.2% type 1 diabetes, 72.8% type 2 diabetes), there were 4,778 cases of DKA at delivery hospitalization (89.1% type 1 diabetes, 10.9% type 2 diabetes). The frequency of DKA at delivery hospitalization was 1.2% (4.0% with type 1 diabetes, 0.2% with type 2 diabetes), and the mean annual percentage change was 10.8% (95% CI, 8.2–13.2%). Diabetic ketoacidosis at delivery hospitalization was significantly more likely among those who had type 1 diabetes compared with those with type 2 diabetes, who were younger in age, who delivered at larger and metropolitan hospitals, and who had Medicaid insurance, lower income, multiple gestations, and prior psychiatric illness. Diabetic ketoacidosis during the delivery hospitalization was associated with an increased risk of nontransfusion SMM (20.8% vs 2.4%, adjusted odds ratio [aOR] 8.18, 95% CI, 7.20–9.29), critical care procedures (7.3% vs 0.4%, aOR 15.83, 95% CI, 12.59–19.90), cardiac complications (7.8% vs 0.8%, aOR 8.87, 95% CI, 7.32–10.76), acute renal failure (12.3% vs 0.7%, aOR 9.78, 95% CI, 8.16–11.72), and transfusion (6.2% vs 2.2%, aOR 2.27, 95% CI, 1.87–2.75), as well as preterm birth (31.9% vs 13.5%, aOR 2.41, 95% CI, 2.17–2.69) and hypertensive disorders of pregnancy (37.4% vs 28.1%, aOR 1.11, 95% CI, 1.00–1.23). In secondary analyses, the overall frequency of antepartum DKA was 3.1%, and the mean annual percentage change was 4.1% (95% CI, 0.3–8.6%); the overall frequency of postpartum DKA was 0.4%, and the mean annual percentage change was 3.5% (95% CI, −1.6% to 9.6%). Of 3,092 antepartum hospitalizations among individuals with DKA, 15.7% (n=485) had a recurrent case of DKA at delivery hospitalization. Of 1,419 postpartum hospitalizations among individuals with DKA, 20.0% (n=285) previously had DKA at delivery hospitalization. The above risk factors for DKA at delivery hospitalization were similar for DKA at antepartum and postpartum hospitalizations. CONCLUSION: The frequency of DKA at delivery hospitalization and antepartum hospitalizations for DKA increased between 2010 and 2020 among deliveries in individuals with pregestational diabetes in the United States. Diabetic ketoacidosis is associated with an increased risk of maternal morbidity and adverse pregnancy outcomes. Risk factors for DKA at delivery were similar to those for DKA during the antepartum and postpartum periods.