Cost of morbidities in very low birth weight infants

Abstract

Objective: To determine the association between direct costs for the initial neonatal intensive care unit hospitalization and 4 potentially preventable morbidities in a retrospective cohort of very low birth weight (VLBW) infants (birth weight <1500 g).

Study design: The sample included 425 VLBW infants born alive between July 2005 and June 2009 at Rush University Medical Center. Morbidities included brain injury, necrotizing enterocolitis, bronchopulmonary dysplasia, and late-onset sepsis. Clinical and economic data were retrieved from the institution's system-wide data and cost accounting system. A general linear regression model was fit to determine incremental direct costs associated with each morbidity.

Results: After controlling for birth weight, gestational age, and sociodemographic characteristics, the presence of brain injury was associated with a $12048 (P = .005) increase in direct costs; necrotizing enterocolitis, with a $15 440 (P = .005) increase; bronchopulmonary dysplasia, with a $31565 (P < .001) increase; and late-onset sepsis, with a $10055 (P < .001) increase. The absolute number of morbidities was also associated with significantly higher costs.

Conclusion: This study provides collective estimates of the direct costs incurred during neonatal intensive care unit hospitalization for these 4 morbidities in VLBW infants. The incremental costs associated with these morbidities are high, and these data can inform future studies evaluating interventions aimed at preventing or reducing these costly morbidities.

Figure 1

Marginal Cost of Morbidities by Birth Weight, Adjusted for Infant Socio-Demographic Characteristics Notes: Abbreviations: Brain injury includes the presence of one of the following: intraventricular hemorrhage, periventricular leukomalacia, or acquired hydrocephalus; NEC = necrotizing enterocolitis; BPD = bronchopulmonary dysplasia. Regression model fit with a gamma distribution and log link. Direct costs adjusted to 2009 dollars. Model controls for birth weight, gestational age, race/ethnicity, gender, and primary payer source. Adjusted costs from regression model are simulated for the modal characteristics of the sample, including African American/Black, male, Medicaid coverage, and 29–36 weeks GA (1250–1499g), 27–28 weeks GA (1000–1249g), 25–26 weeks GA (750–999g) and under 25 weeks GA (<750g). The marginal effect represents the difference in adjusted direct costs when the morbidity is present compared to costs when none of the morbidities are present. The marginal effect of all four morbidities is the difference in adjusted direct costs when brain injury, NEC, BPD, and late onset sepsis are all present compared to adjusted direct costs when none of morbidities are present.