Persistent Organochlorine Pollutants in Plasma, Blood Pressure, and Hypertension in a Longitudinal Study

Persistent organochlorine pollutants (POPs) have shown to be involved in the atherosclerotic process and to cause endothelial cell dysfunction. To assess longitudinally whether plasma concentrations of different POPs were associated with blood pressure and risk of hypertension in middle-aged women and men. Study subjects were 850 participants in the VIP (Västerbotten Intervention Programme) with 2 blood samples and blood pressure measurements, 10 years apart, during 1990 to 2003 (baseline) and during 2000 to 2013 (follow-up). Dioxin-like and nondioxin-like polychlorinated biphenyls (DL-PCBs, NDL-PCBs) and p,p'-dichlorodiphenyldichloroethylene (DDE) were measured. Associations were assessed using generalized estimating equations. At baseline sampling 49% and at follow-up 64% had hypertension. DL-PCBs and DDE, but not NDL-PCBs or hexachlorobenzene, were associated with hypertension. Only the association for DL-PCBs remained statistically significant after lipid-standardization and adjustment for body mass index and total serum lipids. The multivariable-adjusted odds ratio of hypertension based on repeated measurements were 1.52 (95% confidence interval, 1.08-2.13) for DL-PCBs (third versus first tertile of lipid-standardized POPs). In stratified adjusted analyses, odds ratio for those born after 1950 increased to 3.99 (95% confidence interval, 2.15-7.43), whereas no association was observed among those born earlier. Based on repeated measurements, the accumulated exposure to DL-PCBs and DDE, although less clear for the latter, may disrupt the normal blood pressure levels and increase the odds of hypertension. Moreover, individuals experiencing early-life POP exposure may be at elevated risk of vascular POP effects.