Air pollution promotes the onset and progression of cardiovascular-kidney-metabolic syndrome: a nationwide prospective cohort study.

BACKGROUND

Air pollution and cardiovascular-kidney-metabolic (CKM) syndrome have emerged as major global public health challenges. However, limited evidence exists on the association between air pollution exposure and CKM incidence and progression.

METHOD: We analyzed data from participants across CKM stages 0-5 enrolled in the China Health and Retirement Longitudinal Study. Ambient air pollutant concentrations were obtained from the China High Air Pollutants database. Binary logistic regression and weighted quantile sum (WQS) regression models were applied to assess the impacts of individual and combined air pollutants on CKM incidence. Cumulative exposure models were employed to study the long-term effects of pollutants on CKM progression. CKM stages were modeled as ordered categorical outcomes using proportional odds models to examine the association between pollutant levels and CKM progression.

RESULTS

A total of 4,026 individuals were included in the main analysis. Each interquartile range increase in particulate matter with aerodynamic diameters ≤ 1 μm (PM1; OR = 1.008, 95% CI: 1.001-1.015, p < 0.05), ≤ 2.5 μm (PM2.5; OR = 1.009, 95% CI: 1.002-1.015, p < 0.01 ), ≤ 10 μm (PM10; OR = 1.010, 95% CI: 1.004-1.016, p < 0.01), nitrogen dioxide (NO2; OR = 1.011, 95% CI:1.004-1.018, p < 0.01), and ozone (O3; OR = 1.014, 95% CI: 1.006-1.021, p < 0.01) was significantly associated with increased CKM risk. The combined effect of multiple pollutants, reflected by the WQS index, was associated with a 77.7% higher risk of CKM incidence (OR = 1.777, 95% CI: 1.143-2.762, p < 0.05). PM10 (OR = 1.160, 95% CI: 1.059-1.270, p < 0.05) and sulfur dioxide (SO2; OR = 1.122, 95% CI: 1.018-1.236, p < 0.05) were significant contributors to CKM progression. In the cumulative effect analysis of 2,146 individuals, 5-year cumulative PM10 exposure was positively associated with CKM progression (OR = 1.027, 95% CI: 1.001-1.055, p < 0.05).

CONCLUSION

Air pollution is a significant environmental determinant of both CKM incidence and progression. Combined and cumulative effects of multiple pollutants may further enhance CKM risk.