Measuring severe neonatal morbidity using hospital discharge data in France

Abstract

Background Measuring infant health at birth is key for surveillance and research in obstetrics and neonatology, but there is no international consensus on morbidity indicators. The Neonatal Adverse Outcome Indicator (NAOI) is a composite indicator, developed in Australia, which measures the burden of severe neonatal morbidity using hospital discharge data. Objective To evaluate the applicability of the NAOI in France for surveillance and research. Methods We constituted a cohort of live births ≥24 weeks’ gestational age in Metropolitan France from 2014 to 2015 using hospital discharge, insurance claims and cause of death data. Outlier hospitals were identified using funnel plots of standardised morbidity ratios (SMR), and their coding patterns were assessed. We compared the NAOI and its component codes with published Australian and English data and estimated unadjusted and adjusted risk ratios for known risk factors for neonatal morbidity. Results We included 1,459,123 births (511 hospitals). Twenty‐eight hospitals had SMR above funnel plot control limits. Newborns with NAOI morbidities in these hospitals had lower mortality and shorter stays than in other hospitals. Amongst within‐limit hospitals, NAOI prevalence was 4.8%, comparable to Australia (4.6%) and England (5.4%). Most individual components had a similar prevalence, with the exception of respiratory support, intravenous fluid procedures and infection. NAOI was lowest at 39 weeks (2.2%) with higher risks for maternal age ≥40 (relative risk [RR] 1.47, 95% confidence interval [CI] 1.42, 1.51), state medical insurance (RR 1.60, 95% CI 1.52, 1.68), male sex (RR 1.21, 95% CI 1.19, 1.23) and birthweight <3rd percentile (RR 4.60, 95% CI 4.51, 4.69). Conclusions The NAOI provides valuable information on population prevalence of severe neonatal morbidity and its risk factors. Whilst the prevalence was similar in high‐income countries with comparable neonatal mortality levels, ensuring valid comparisons between countries and hospitals will require further work to harmonize coding procedures, especially for infection and respiratory morbidity.

In France, the organization of perinatal care has a direct influence on the outcome of the mother and the newborn: Contribution from a French nationwide study

“…Each component of the NAOI was found to be associated with risks of death and rehospitalization. 21 Similar results were found in England 22 with a few coding modifications in the construction of the NAOI; the same was tested in France in 2022 23 (Table S2). Both SMM and NAOI were calculated and analyzed retrospectively.…”

Morbidity and mortality of newborns born to immigrant and nonimmigrant females residing in low-income neighbourhoods

“…10,11 Limited research has examined SNM in high-income countries. 2,6,8,[12][13][14][15][16][17] Studies have primarily focused on deriving and validating the criteria to define SNM, 1,3,10 quantifying the prevalence of SNM and identifying risk factors in African, Asian and Latin American regions. 11,[18][19][20][21][22][23][24][25][26][27] Research is also lacking on a range of upstream social determinants of health inequity and their influence on SNM.…”

Composite Perinatal Morbidity Metrics: Getting closer but still with challenges

“…In this issue of Paediatric and Perinatal Epidemiology , Lebreton and colleagues 6 employed a composite measure of neonatal morbidity 7 to compare national hospital discharge data from France, the United Kingdom and Australia and then analyse data from 511 hospitals in Metropolitan France. The Neonatal Adverse Outcome Indicator (NAOI) is a composite of 18 morbidities and complications derived from ICD‐10 diagnostic and procedure codes and intended to include all severe neonatal morbidities and cover the entire population.…”

“…In the study by Lebreton, 6 respiratory distress, intravenous fluids and respiratory support account for approximately two‐thirds of cases. The current CDC composite measure of severe maternal morbidity is now dominated by maternal blood transfusion (over 50%).…”

“…Recent data indicate that cases with transfusion alone almost never result in a mortality (this was the original construct for the measure); thus, in 2021, transfusions were removed from the measure specifications 10 . Also, in the study of Lebreton, 6 almost all the difference between outlier hospitals from those within limits came from the use of intravenous fluids. Many clinicians might consider this to be a relatively minor morbidity, reflecting local practices for treating hypoglycaemia.…”