Life course cumulative PM2.5 exposure since childhood and albuminuria in midlife: a 30-year prospective cohort study

Abstract Background Previous studies have confirmed the adverse effect of ambient fine particulate matter (PM2.5) on kidney and cardiovascular diseases. However, the effects of long-term cumulative PM2.5 exposure on albuminuria, particularly from childhood to middle age, remains uncertain. Purposes We aimed to investigate the association between cumulative PM2.5 exposure and albuminuria across three distinct time frames using data from the 30-year population-based cohort study. Methods Using data from the ongoing cohort of Hanzhong Adolescent Hypertension study, 1643 children and adolescents were followed with 6 visits over 30 years. The annual mean PM2.5 concentration for the period 1987-2017, at the address of each participant, was obtained from the MERRA-2 and CHAP datasets in China. We assessed cumulative PM2.5 exposure as the area under the curve (AUC) and used the linear regression models to estimate the association between cumulative PM2.5 exposure and urinary albumin-to-creatinine ratio (uACR) in 2017. Results In full adjustment for potential confounders, childhood and life course cumulative PM2.5 exposure was positively associated with uACR in midlife [childhood: β=0.103 (95%CI: 0.003, 0.202); life course: β=0.078 (95%CI: 0.004, 0.153)]. However, the relationship between adulthood cumulative PM2.5 exposure and uACR in middle age was not statistically significant. In addition, the associations of adulthood and life course cumulative PM2.5 exposure with uACR in middle age were only observed in non-smokers [β=0.109 (95% CI: 0.002, 0.216)], but not in smokers. Conclusions Cumulative PM2.5 exposure during childhood and over the life course is associated with higher uACR in midlife, especially for children and non-smokers. Lowering PM2.5 pollution early in life could prevent the development of renal dysfunction and cardiovascular disease in later life.