Objective: Inpatient conditions that might be avoided through improved outpatient services are called Ambulatory Care Sensitive Indicators, and they include pyelonephritis in nonpregnant adults. No such indicators have been developed for pregnant women. We examine whether hospital-specific rates of gestational pyelonephritis may serve as a measure of the quality of ambulatory maternal care.
Methods: The California Department of Health Services provided an administrative data set linking maternal and newborn delivery records for 1997 with antepartum hospital admissions. We created a "low-risk" study population by largely excluding women with maternal, fetal, and placental morbidities and those with no first-trimester prenatal care. We generated hospital-specific infection rates using a Bayesian hierarchical logistic regression model.
Results: We identified 280,816 low-risk women, of whom 1,853 (0.66%) had at least 1 inpatient admission for gestational pyelonephritis. The model suggested only 2 risk factors: MediCal as a payer (odds ratio 1.60, 95% confidence interval 1.46-1.80 compared with all other payers), and African-American race (odds ratio 1.24, 95% confidence interval 1.10-1.41 compared with white race). Women with pyelonephritis were more than twice as likely to deliver preterm. Adjusted rates of gestational pyelonephritis for the 291 hospitals in the sample ranged from 0.22% to 2.64%.
Conclusion: These findings suggest that because of its preventability, its consequent related morbidity, and the variation in hospital-specific rates, gestational pyelonephritis meets both clinical and technical requirements as a quality indicator for ambulatory maternal care. The use of such rates would provide an opportunity for hospitals to improve patient outcomes through partnership with obstetricians in the management of women at risk.
Level of evidence: II-3.