Association of socio-economic status and ethnicity with mortality and morbidity of premature infants admitted to neonatal intensive care in South Auckland, New Zealand

Abstract

Aim: Socio-economic status (SES) and ethnicity have been associated with worse maternal and fetal outcomes. Counties Manukau is a region of New Zealand which has a high portion of the population living in areas of low SES and has a higher population of ethnic minorities (Pacific Islander, Asian and Maaori). To determine whether SES and ethnicity are associated with worse mortality and morbidity in preterm infants in Counties Manukau Hospital, New Zealand.

Methods: This retrospective cohort study compared the infants of mothers who live in the most deprived neighbourhoods to the infants of mothers who live in the least deprived neighbourhoods. Infants born between 2000 and 2019 were included if <30 weeks gestation or <1500 g and born in hospital. Primary outcome was combined mortality/morbidity.

Results: Univariate analysis showed demographic differences between the SES and ethnic groups, for example maternal age and maternal smoking. Using logistic regression, SES was not associated with worse neonatal outcomes for the most deprived SES (n = 624) compared to least deprived SES (n = 164). Ethnicity (n = 1326) was not associated with worse neonatal outcomes. Gestational age and maternal smoking were associated with neonatal mortality/morbidity; gestational age and antenatal steroids were associated with neonatal mortality. It was notable that the proportion of the study population in the less deprived groups used for the comparisons was relatively low.

Conclusions: For preterm, in-hospital births in Counties Manukau over a 20-year period, neonatal outcomes were the same regardless of SES or ethnicity.

Keywords: deprivation; ethnicity; morbidity; mortality; preterm; socio-economic status.