PCB Exposure Boosts Heart Disease Risk in T2D

TOPLINE:

Elevated concentrations of serum polychlorinated biphenyls (PCBs) increase the risk for incident cardiovascular disease (CVD) by up to 30% among patients with type 2 diabetes (T2D).

METHODOLOGY:

• Prior studies haven’t examined the impact of PCB exposure on patients with T2D, a group that may be more vulnerable to the heightened risk for CVD associated with these persistent organic pollutants.
• Researchers analyzed 2806 participants with T2D (median age, 64 years; 51.96% women) from the Dongfeng-Tongji cohort in China; the presence of T2D was determined through self-reported physician diagnosis, use of glucose-lowering medications/insulin, or fasting plasma glucose levels ≥ 7.0 mmol/L at baseline.
• Serum concentrations of seven indicator PCBs were analyzed using gas chromatography-mass spectrometry, with PCBs categorized as lower- or higher-chlorinated.
• The outcome event used for the study was the first occurrence of CVD, encompassing coronary heart disease or stroke, during the follow-up period.
• Cox proportional hazard regression models and quantile g-computation were used to determine the associations of serum PCB levels with incident CVD risk.

TAKEAWAY:

• After a median follow-up duration of 10.03 years, 1180 participants developed CVD, of whom 909 had first-onset coronary heart disease and 271 first-onset stroke.
• The detection rate of six PCBs (PCB28, PCB52, PCB101, PCB138, PCB153, and PCB180) reached 100%.
• Higher serum concentrations of PCB28, PCB52, and PCB101 increased the risk for CVD by 25%, 30%, and 28%, respectively; the association was even stronger in case of lower-chlorinated PCBs.
• Analysis revealed PCB101, PCB52, and PCB28 as the top three contributors to the increased risk for CVD among the PCBs studied.
• Age over 65 years was associated with an increased susceptibility to the PCB-related risk for CVD.

IN PRACTICE:

“The PCB congeners that increased the risk of CVD were predominantly lower-chlorinated PCBs,” the authors wrote, adding that, “PCBs may directly cause CVD by inducing atherosclerosis.”

SOURCE:

This study was led by Jun An, Department of Occupational and Environmental Health and State Key Laboratory of Environmental Health for Incubating, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. It was published online in The Journal of Clinical Endocrinology & Metabolism.

LIMITATIONS:

The single-site detection may have made it difficult to reflect the changes and long-term trends of PCB concentrations in humans. Researchers measured only serum PCBs and could not rule out the effects of exposure to other pollutants and possible combined effects. Despite adjusting for various covariates, unmeasured confounding factors that may have influenced the results remained.

DISCLOSURES:

This study received support through grants from the National Key Research and Development Program of China and the National Natural Science Foundation of China. The authors declared no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.