The global and national burden of chronic kidney disease attributable to ambient fine particulate matter air pollution: a modelling study

Abstract

Introduction: We aimed to integrate all available epidemiological evidence to characterise an exposure-response model of ambient fine particulate matter (PM_2.5) and the risk of chronic kidney disease (CKD) across the spectrum of PM_2.5 concentrations experienced by humans. We then estimated the global and national burden of CKD attributable to PM_2.5.

Methods: We collected data from prior studies on the association of PM_2.5 with CKD and used an integrative meta-regression approach to build non-linear exposure-response models of the risk of CKD associated with PM_2.5 exposure. We then estimated the 2017 global and national incidence, prevalence, disability-adjusted life-years (DALYs) and deaths due to CKD attributable to PM_2.5 in 194 countries and territories. Burden estimates were generated by linkage of risk estimates to Global Burden of Disease study datasets.

Results: The exposure-response function exhibited evidence of an increase in risk with increasing PM_2.5 concentrations, where the rate of risk increase gradually attenuated at higher PM_2.5 concentrations. Globally, in 2017, there were 3 284 358.2 (95% UI 2 800 710.5 to 3 747 046.1) incident and 122 409 460.2 (108 142 312.2 to 136 424 137.9) prevalent cases of CKD attributable to PM_2.5, and 6 593 134.6 (5 705 180.4 to 7 479 818.4) DALYs and 211 019.2 (184 292.5 to 236 520.4) deaths due to CKD attributable to PM_2.5. The burden was disproportionately borne by low income and lower middle income countries and exhibited substantial geographic variability, even among countries with similar levels of sociodemographic development. Globally, 72.8% of prevalent cases of CKD attributable to PM_2.5 and 74.2% of DALYs due to CKD attributable to PM_2.5 were due to concentrations above 10 µg/m³, the WHO air quality guidelines.

Conclusion: The global burden of CKD attributable to PM_2.5 is substantial, varies by geography and is disproportionally borne by disadvantaged countries. Most of the burden is associated with PM_2.5 levels above the WHO guidelines, suggesting that achieving those targets may yield reduction in CKD burden.

Keywords: environmental health; public health.

Figure 1

Integrated non-linear exposure–response curve of PM_2.5 and CKD. Curves are presented for modelling strategies where: (A) only PM_2.5 study data were used and cross-sectional studies were deweighted; (B) only PM_2.5 study data were used; (C) data from studies on proxy exposure were additionally incorporated and cross-sectional studies were deweighted; and (D) data from studies on proxy exposure were additionally incorporated. Ninety-five per cent UI are presented as bands. A reference value of 2.4 µg/m³ was used; all risk under the reference was set to unity. PM_2.5, ambient fine particulate matter.

Figure 2

Global burden of CKD attributable to PM_2.5 in 194 countries and territories. (A) Prevalence of CKD attributable to PM_2.5; (B) age-standardised disability-adjusted life-years (DALYs) rate (per 100 000) due to CKD attributable to PM_2.5. Countries are coloured by decile. CKD, chronic kidney disease; PM_2.5, ambient fine particulate matter. ATG, Antigua and Barbuda; FSM, Federated States of Micronesia; Isl, Island; LCA, Saint Lucia; TLS, Timor-Leste; TTO, Trinidad and Tobago; VCT, Saint Vincent and the Grenadines.

Figure 3

Map of the estimated to expected ratio of age-standardised disability-adjusted life-years (DALYs) due to CKD attributable to PM_2.5 based on level of sociodemographic development. Countries and territories are coloured by the estimated to expected ratio the age-standardised DALYs rate based on their sociodemographic index (SDI), where a ratio greater than one indicates greater than expected age-standardised DALYs, while a ratio less than one is less than expected. CKD, chronic kidney disease.