The spatial-temporal effect of air pollution on GP visits and hospital admissions by ethnicity in the United Kingdom: An individual-level analysis

BackgroundAir pollution has been associated with increased rates of hospital admissions and general-practitioner (GP) visits. Yet, more research is to be done to reveal the spatial-temporal dimension of this association and whether ethnic minorities experience greater effects from exposure to air pollution compared to the rest of population. This study investigates the spatial-temporal effect of air pollution on GP visits and hospital admissions by ethnicity in the United-Kingdom (UK). MethodsWe used individual-level longitudinal data from the "UK Household Longitudinal Study" including 46,442 adult individuals who provided 140,466 responses across five years (2015-2019). This data was linked to yearly concentrations of NO2, SO2, and particulate-matter (PM10, PM2.5) pollution using the Lower-Super-Output-Area (LSOA) of residence for each individual. We distinguished between spatial (between areas) and temporal (across time within each area) effects of air pollution on GP visits and hospital admissions and we used multilevel mixed-effects ordered logistic models for analysis. ResultsResults showed higher odds of outpatient hospital admissions with increasing concentrations of NO2 (OR=1.009; 95%CI=1.006-1.013), SO2 (OR=1.063; 95%CI=1.030-1.097), PM10 (OR=1.013; 95%CI=1.006-1.021), and PM2.5 (OR=1.022; 95%CI=1.012-1.032) pollutants. Higher odds of GP visits were also observed with increasing concentrations of NO2 (OR=1.011; 95%CI=1.007-1.015) and SO2 (OR=1.123; 95%CI=1.087-1.160) pollutants. Decomposing air pollution into between (spatial: across LSOAs) and within (temporal: across years within each LSOA) effects, showed significant between effects for air pollution on GP visits and hospital admissions, but not within effects. We observed no differences between ethnic minorities and British-white for the association between air pollution and hospital admissions and GP visits. ConclusionUsing individual-level longitudinal data, our study supports the presence of a spatial-temporal association between air pollution and hospital admissions and GP visits. However, ethnic minorities do not seem to experience greater health-related effects from exposure to air pollution compared to the rest of population.