Evaluating the Effect of Hospital and Insurance Type on the Risk of 1-year Mortality of Very Low Birth Weight Infants

Abstract

OBJECTIVES We examined the effect of hospital type and medical coverage on the risk of 1-year mortality of very low birth weight (VLBW) infants while adjusting for possible selection bias. METHODS The study population was limited to singleton live birth infants having birth weight between 500 and 1,500 grams with no congenital anomalies who were born in Arkansas hospitals between 2001 and 2007. Propensity score (PS) matching and PS covariate adjustment were used to mitigate selection bias. Additionally, a conventional multivariable logistic regression model was used for comparison purposes. RESULTS Generally, all three analytical approaches provided consistent results in terms of the estimated relative risk, absolute risk reduction, and the number needed to treat (NNT). Using the PS matching method, VLBW infants delivered at a hospital with a neonatal intensive care unit (NICU) were associated with a 35% relative decrease (95% bootstrap CI: 18.5% – 48.9%) in the risk of 1-year mortality as compared to those infants delivered at non-NICU hospitals. Furthermore, our results showed that on average, 16 VLBW infants (95% bootstrap CI: 11 – 32), would need to be delivered at a hospital with an NICU to prevent one additional death at one year. However, there was not a difference in the risk of 1-year mortality between VLBW infants born to Medicaid-insured versus non-Medicaid-insured women. CONCLUSIONS Estimated relative risk of infant mortality was significantly lower for births that occurred in hospitals with an NICU; therefore, greater efforts should be made to deliver VLBW neonates in an NICU hospital.

Geographic Distribution of Maternal Group B Streptococcus Colonization and Infant Death During Birth Hospitalization: Eastern Wisconsin

“…A similar finding was seen in Arkansas, where Medicaid versus non-Medicaid insurance (and white vs. nonwhite race) were not predictive of 1-year mortality of very low-birth-weight infants when adjusting for births that occurred in hospitals with or without a neonatal intensive care unit. 29 Our study reinforced that place does matter. Likely a complex interplay between neighborhood, race, marital status and income/insurance status, an unmeasured variable that may be described as parental stress and other unmeasured factors contribute to both preterm birth and death following birth hospitalization.…”

“…27 Racial and insurance disparities are recognized as significant predictors of perinatal mortality, preterm birth and death among low-birth-weight infants. 23,24,28,29 Recently, environmental epigenetics, nutritional deficiencies and stress have been suggested as etiologic factors in adverse perinatal outcomes, perhaps mediated by differential inflammatory responses. 28,30 Racial disparities were certainly seen in our study, however, race/ethnicity did not remain a significant predictor of infant death when ZIP code group was included on multivariable analysis of the entire data set nor in the subset representing the 532XX ZIP code group.…”

A deterministic balancing score algorithm to avoid common pitfalls of propensity score matching

“…Because of this added overhead, the bootstrapping approach seems to be used very rarely. In comparison to the widespread use of PSM, only few studies, e.g., [43][44][45], make use of bootstrapping with PSM. We prove that the result of executing PSM with bootstrapping will converge to the result delivered by DBSeM which avoids the overhead of bootstrapping and does not suffer from the remaining pitfalls of PSM.…”