Associations of long-term exposure to ambient air pollutants with metabolic syndrome: The Wuhan Chronic Disease Cohort Study (WCDCS).

BACKGROUND

Evidence on the associations between long-term exposure to ambient air pollutants (including particle with aerodynamic diameter ≤10 μm (PM), particle with aerodynamic diameter ≤2.5 μm (PM), ozone (O), nitrogen dioxide (NO), and sulfur dioxide (SO)) and prevalence of metabolic syndrome (MetS) remains inconclusive. This study aimed to determine the associations based on a case-control study nested in the Wuhan Chronic Disease Cohort study (WCDCS), a population-based study with baseline survey in 2019.

METHODS

A total of 10,253 residents living in Wuhan were recruited. The 3-year average concentrations of main pollutants (PM, PM, O, NO, and SO) at residences prior to the survey date were estimated to evaluate the long-term exposures. The generalized linear mixed models were used to investigate the changes in MetS prevalence by an IQR increases in each air pollutant exposure concentrations. Interaction effects between air pollutants and demographic, lifestyle, and dietary factors on MetS were evaluated by including an interactive item in the main model.

RESULTS

The prevalence of MetS in Wuhan was 9.8%, and the 3-year exposure concentrations of PM, PM, O, NO, and SO were 84.1 μg/m, 50.5 μg/m, 55.7 μg/m, 46.0 μg/m, and 9.4 μg/m, respectively. Higher PM, PM and O exposure concentrations were associated with an elevated MetS prevalence (e.g. an IQR increase in PM, OR = 1.193, 95% confidence intervals (95%CIs): 1.028, 1.385; for O, OR = 1.074, 95%CIs: 1.025, 1.124), whereas NO, and SO were negatively or insignificant correlated with odds of Mets (e.g. an IQR increase in NO, OR = 0.865, 95%CIs: 0.795, 0.941). Males, smokers, alcohol drinkers and individuals who intake fruits occasionally exposure to PM and PM were found had a higher risk of developing MetS.

CONCLUSIONS

Long-term exposure to higher concentrations of ambient air pollutants may elevate the prevalence of MetS in populations in Central China. Susceptible individuals especially those with unhealthy lifestyles had a higher risk for MetS.