FRIDAY, Aug. 7, 2020 (HealthDay News) -- An expanded obstetric comorbidity score improves the prediction of severe maternal morbidity, according to a study published online Aug. 6 in Obstetrics & Gynecology.
Stephanie A. Leonard, Ph.D., from Stanford University in California, and colleagues developed and validated an expanded obstetric comorbidity score for predicting severe maternal morbidity using discharge data from birth hospitalizations in California during 2016 to 2017. Twenty-seven potential patient-level risk factors for severe maternal morbidity were identified; these factors were ranked based on adjusted risk ratios (aRRs) using a targeted causal inference approach integrated with machine learning.
The researchers found that the rates of severe maternal morbidity and nontransfusion severe maternal morbidity were 168 and 74 per 10,000 births, respectively, among 919,546 births. The highest- and lowest-risk comorbidities were placenta accreta spectrum (aRRs, 30.5 for severe maternal morbidity and 54.7 for nontransfusion severe maternal morbidity) and gestational diabetes mellitus (aRRs, 1.06 and 1.12, respectively). The expanded comorbidity scores had good overall performance (C-statistic, 0.78 for severe maternal morbidity and 0.84 for nontransfusion severe maternal morbidity in California data; 0.82 and 0.87, respectively, in national data). There was good concordance between predicted and actual risks of outcomes in calibration plots.
"The scores can serve as an adjustment strategy to compare severe maternal morbidity and nontransfusion severe maternal morbidity rates across hospitals and other patient populations that vary in comorbidity case mix," the authors write.