646 - Maximal Weight Loss and Association with In-Hospital Mortality among Moderately Preterm Newborns in a Tertiary Referral Hospital in Addis Ababa, Ethiopia

Physiologic weight loss is an important component of the fetal-to-neonatal transition. Recent data in high-income countries suggests that a maximal weight loss (MWL) of 5-15% from birth weight is associated with improved in-hospital outcomes in extremely preterm newborns (24-28 weeks’ gestation). However, it is unclear if there exists an optimal degree of MWL among premature newborns in low- and middle-income countries.  

Objective: We aimed to describe MWL patterns among moderately preterm (MP; < 34 weeks’ gestation at birth) and the association between MWL and mortality in a large tertiary referral hospital - St. Paul’s Hospital Millennium Medical College (SPHMMC) neonatal intensive care unit (NICU) - in Addis Ababa, Ethiopia.

Design/Methods:

We performed a prospective, observational, cross-sectional study including newborns born < 34 weeks’ gestation or < 1,500 grams birth weight with no known congenital anomalies who survived for 1 week. First, we evaluated weight loss and total fluid administration (TFA) patterns among MP newborns. The association between categories of MWL and TFA with in-hospital mortality and length of hospital stay was assessed using logistic and linear regression models adjusting for known confounders.

Results: Among n=115 MP newborns admitted to the SPHMMC NICU, the median nadir for weight loss occurred on day 6 after birth (Figure 1A) with only 55% of neonates born < 30 weeks’ gestation regaining birthweight in the first month or prior to discharge (Figure 1B). Neonates born at < 30 weeks’ gestation had median MWL of 21% compared with 12% and 9% for those born at 30-31 and 32-33 weeks’ gestation, respectively (Figure 1B). While MP newborns with MWL 5-15% had fewer deaths than those with >15% or < 5% MWL (9.4% vs 23.5% and 14.3%, respectively), this was not statistically significant (p=0.26 and p=0.82, respectively; Table 1). TFA was not associated with increased odds of mortality or longer length of stay (Table 2).

Conclusion(s):

Nearly half of the most vulnerable and premature newborns, those born < 30 weeks’ gestation, did not regain birthweight prior to discharge. This same population had a median MWL (21%) more than double of those born at 32-33 weeks’ gestation (9%). While not statistically significant in our single-center study, our findings suggest 5-15% MWL may be associated with a lower odds of mortality. Large, multicenter studies are needed to evaluate the impact of MWL on in-hospital outcomes among preterm newborns in LMICs and determine whether targeting a physiologic weight loss of 5-15% below birthweight is able to prevent adverse health outcomes.