Persisting inequalities in birth outcomes related to neighbourhood deprivation

Abstract

IntroductionHealth inequalities can be observed in early life as unfavourable birth outcomes. Evidence indicates that neighbourhood socioeconomic circumstances influence health. However, studies looking into temporal trends in inequalities in birth outcomes including neighbourhood socioeconomic conditions are scarce. The aim of this work was to study how inequalities in three different key birth outcomes have changed over time across different strata of neighbourhood deprivation.MethodsNationwide time trends ecological study with area-level deprivation in quintiles as exposure. The study population consisted of registered singleton births in the Netherlands 2003–2017 between 24 and 41 weeks of gestation. Outcomes used were perinatal mortality, premature birth and small for gestational age (SGA). Absolute rates for all birth outcomes were calculated per deprivation quintile. Time trends in birth outcomes were examined using logistic regression models. To investigate relative inequalities, rate ratios for all outcomes were calculated per deprivation quintile.ResultsThe prevalence of all unfavourable birth outcomes decreased over time: from 7.2 to 4.1 per 1000 births for perinatal mortality, from 61.8 to 55.6 for premature birth, and from 121.9 to 109.2 for SGA. Inequalities in all birth outcomes have decreased in absolute terms, and the decline was largest in the most deprived quintile. Time trend analyses confirmed the overall decreasing time trends for all outcomes, which were significantly steeper for the most deprived quintile. In relative terms however, inequalities remained fairly constant.ConclusionIn absolute terms, inequalities in birth outcomes by neighbourhood deprivation in the Netherlands decreased between 2003 and 2017. However, relative inequalities remained persistent.

Neighbourhood deprivation and perinatal health in the Netherlands

“…Given that some experts favour monitoring absolute inequality for public health planning, management and evaluation,7 8 and that declines in relative inequality seem conceivable under far fewer conditions in Western European countries,9 it is tempting to conclude from the overall findings that deprivation-related perinatal inequalities have generally improved in the Netherlands. While absolute rates of birth outcomes decreased across all areas ranging from least (top quintile) to most (bottom quintile) deprived, the largest improvements were observed in the most deprived quintile 4…”

“…A robust literature has found that babies who are born to mothers living in areas of higher deprivation have an increased risk of adverse birth outcomes, such as prematurity and restricted fetal growth 3. Given that these suboptimal outcomes lead to poorer developmental trajectories in childhood4 and chronic diseases in later adulthood,5 health at birth is a profoundly important priority for public health and social care. Despite substantial improvements in perinatal morbidity and mortality over time in Europe as a whole, advances have been slower in the Netherlands 4…”

“…Given that these suboptimal outcomes lead to poorer developmental trajectories in childhood4 and chronic diseases in later adulthood,5 health at birth is a profoundly important priority for public health and social care. Despite substantial improvements in perinatal morbidity and mortality over time in Europe as a whole, advances have been slower in the Netherlands 4…”

“…Bertens et al report that neighbourhood deprivation-related inequalities in perinatal mortality, premature birth and small for gestational age (SGA) in the Netherlands have decreased in absolute terms, but persisted in relative terms, from 2003 to 2017 4. This begs the question, have perinatal inequalities in the Netherlands improved or not?…”

“…The magnitude of absolute and relative health inequalities may be differentially influenced by the overall level of health in the population6 and helps to explain the observed inconsistency between absolute versus relative trends in perinatal inequalities. The authors estimate that absolute rates for each of the three perinatal outcomes decreased over the 14-year period4 and illustrate the scenario where drops in the overall frequency of the outcome can result in a reduction of absolute inequality, but no change in relative inequality 7. Given that some experts favour monitoring absolute inequality for public health planning, management and evaluation,7 8 and that declines in relative inequality seem conceivable under far fewer conditions in Western European countries,9 it is tempting to conclude from the overall findings that deprivation-related perinatal inequalities have generally improved in the Netherlands.…”