Association between ambient air pollutants and lipid profile: A systematic review and meta-analysis

Background: Studies of the effects of atmospheric pollutants on lipid profiles remain inconsistent and controversial.Aim: The study was aimed to investigate the relationship between the exposure to ambient air pollutants and variations in the blood lipid profiles in the population.Methods: A comprehensive search of three different databases (PubMed, Web of Science, and the Cochrane Library) until December 17, 2022, yielded 17 origional studies fulfilling the inclusion criteria for a meta-analysis. Aggregate effect measures and 95% confidence intervals (95% CI) for the relevant ambient air pollutants were deduced employing random effects models.Results: The collective meta-analysis indicated that long-term exposure to PM1, PM2.5, PM10 and CO showed a substantial correlation with TC (PM1: & beta; = 2.04, 95%CI = 0.15-3.94; PM2.5: & beta; = 1.11, 95%CI = 0.39-1.84; PM10: & beta; = 1.70, 95%CI = 0.67-2.73; CO: & beta; = 0.08, 95%CI = 0.06-0.10), PM10 exhibited a significant association with TG (& beta; = 0. 537,95% CI = 0.09-0.97), whereas HDL-C demonstrated notable relationships with PM1, PM10, SO2 and CO (PM1: & beta; = -2.38, 95%CI = -4.00 to -2.76; PM10: & beta; = -0.77, 95%CI = -1.33 to -0.21; SO2: & beta; = -0.91, 95%CI = -1.73 to -0.10; CO: & beta; = -0.03, 95%CI = -0.05 to 0.00). PM2.5, PM10 also showed significant associations with LDL-C (PM2.5: & beta; = 1.44 95%CI = 0.48-2.40; PM10: & beta; = 1.62 95%CI = 0.90-2.34). Subgroup analysis revealed significant or stronger correlations predominantly in cohort study designs, with higher male comparisons, and in regions exhibiting elevated contaminant levels.Conclusion: In summary, the analysis substantiates that ambient air pollutants can be recognized as potent contributors to alterations in lipid profiles, particularly particulate pollutants which exert more obvious effects on lipid profiles.