Historical exposure to persistent organic pollutants and risk of incident hypertension

• We studied the association of pollutants in adipose tissue with hypertension risk.
• Samples were collected at recruitment and participants followed for 10 years.
• HCB, β-HCH and PCBs were associated with hypertension in individuals with BMI>26.3.

The aim of this study was to assess the influence of adipose tissue concentrations of a group of persistent organic pollutants (POPs) on the risk of hypertension in an adult cohort of residents of Granada (Southern Spain) over a 10-year follow-up. No chemical was significantly associated with the risk of hypertension in the overall population or when models were stratified by sex or median age. However, we found positive associations between log-transformed POP concentrations and hypertension risk in participants with body mass index (BMI) above the median value of 26.3 kg/m2, which were statistically significant for hexachlorobenzene (HR=1.26, 95% CI=1.03–1.56), β-hexachlorocyclohexane (HR=1.25, 95% CI=1.03–1.51), and polychlorinated biphenyl congeners -138 (HR=1.32, 95% CI=1.04–1.69) and -153 (HR=1.36, 95% CI=1.00–1.84). Inverse associations were observed in the subgroup with BMI≤26.3 kg/m2, but none was statistically significant. More research and a longer follow-up period are warranted to verify these associations and elucidate the role of obesity as a potential effect modifier. Given the elevated worldwide frequency of POP exposure and hypertension, the public health impact of this relationship may be substantial.