City-Specific Spatiotemporal Infant and Neonatal Mortality Clusters: Links with Socioeconomic and Air Pollution Spatial Patterns in France

Abstract

Infant and neonatal mortality indicators are known to vary geographically, possibly as a result of socioeconomic and environmental inequalities. To better understand how these factors contribute to spatial and temporal patterns, we conducted a French ecological study comparing two time periods between 2002 and 2009 for three (purposefully distinct) Metropolitan Areas (MAs) and the city of Paris, using the French census block of parental residence as the geographic unit of analysis. We identified areas of excess risk and assessed the role of neighborhood deprivation and average nitrogen dioxide concentrations using generalized additive models to generate maps smoothed on longitude and latitude. Comparison of the two time periods indicated that statistically significant areas of elevated infant and neonatal mortality shifted northwards for the city of Paris, are present only in the earlier time period for Lille MA, only in the later time period for Lyon MA, and decrease over time for Marseille MA. These city-specific geographic patterns in neonatal and infant mortality are largely explained by socioeconomic and environmental inequalities. Spatial analysis can be a useful tool for understanding how risk factors contribute to disparities in health outcomes ranging from infant mortality to infectious disease—a leading cause of infant mortality.

Infant Mortality Related to NO2 and PM Exposure: Systematic Review and Meta-Analysis

“…Most of the studies were conducted in the United-States (in both the north and south) [8,10,[12][13][14][15][16][17][18][19][20][21]. There were also 6 studies conducted in Europe and the UK [9,[22][23][24][25], 7 studies conducted in Asia [26][27][28][29][30][31], and a single study conducted in Africa [32]. Our systematic review is grouped by study design: a majority are ecological studies [9,12,19,20,23,24,31]; others are case crossover studies [8,18,22,25,26,[28][29][30], case-control studies [15][16][17], cohort, and cross sectional studies [10,13,14,27,32].…”

“…While many studies investigated only the overall group of infant mortality [9,10,15,21,[23][24][25][26]32], post-neonatal [8,9,13,21,[25][26][27][28], and neonatal death [9,10,15,21,23,25,26], others explored specific cause of death, mainly by respiratory causes [8,10,[12][13][14][15][16]18,21,[25][26][27]31] and Sudden Infant Death Syndrome (SIDS) [13,15,17,19,21,22,26,27]. Several studies stratified their analysis on an additional covariate.…”

“…Few studies focused on the effects of certain pollutants, namely PM 10 , PM 2.5 , and CO [14], or indeed the effects of just two pollutants, PM 10 and O 3 [8,12,18] or NO 2 and CO [17]. Five studies considered a single pollutant, namely PM 2.5 [16,32], PM 10 [25], or NO 2 [23,24].…”

“…All studies considered air pollution data from monitoring stations, except four studies [23][24][25]32] which based their measures of exposure on a modelling approach ( Table 2). Whichever methodology was applied to characterize residential exposure, most often it was on a daily basis (except in four studies [21,23,24,32], which examined annual indicators). For all air pollutants (PM 10 , PM 2.5 , CO, NO 2 , and SO 2 ), the authors most often used the daily (24 h) average, except in two studies which selected the maximum daily concentrations observed as the indicator of exposure [10,17].…”

Spatiotemporal Frameworks for Infectious Disease Diffusion and Epidemiology

“…Historical time-series modelling of cryptosporidiosis incidence with rainfall has reported positive associations in a global meta-analysis of cryptosporidiosis seasonality [40]. Padilla et al [41] consider impacts on infant mortality (often linked to infection) of socioeconomic factors and air pollution.…”