Prevalence and Predictors of Medical Complexity in a National Sample of VLBW Infants

Abstract

BACKGROUND AND OBJECTIVES: Very low birth weight (VLBW) infants are at high risk for morbidities beyond the neonatal period and ongoing use of health care. Specific morbidities have been studied; however, a comprehensive landscape of medical complexity in VLBW infants has not been fully described. We sought to (1) describe the prevalence of complex chronic conditions (CCCs) and (2) determine the association of demographic, hospital, and clinical factors with CCCs and CCCs or death. METHODS: This retrospective cross-sectional analysis of discharge data from the Kids’ Inpatient Database (2009–2012) included infants with a birth weight <1500 g and complete demographics. Outcomes included having CCCs or having either CCCs or dying. Analyses were weighted; univariate and multiple logistic regression models were used to estimate unadjusted and adjusted odds ratios. A dominance analysis with Cox-Snell R2 determined the relative contribution of demographic, hospital, and clinical factors to the outcomes. RESULTS: Among our weighted cohort of >78 000 VLBW infants, >50% had CCCs or died. After adjustments, the prevalence of CCCs or CCCs or death differed by sex, race and ethnicity, hospital location, US region, receipt of surgery, transfer status, and birth weight. Clinical factors accounted for the highest proportion of the model’s ability to predict CCCs and CCCs or death at 93.3% and 96.3%, respectively, whereas demographic factors were 11.5% and 2.3% and hospital factors were 5.2% and 1.4%, respectively. CONCLUSIONS: In this nationally representative analysis, medical complexity is high among VLBW infants. Varying contributions of demographic, hospital, and clinical factors in predicting medical complexity offer opportunities to investigate future interventions to improve care delivery and patient outcomes.