Arsenic, blood pressure, and hypertension in the Strong Heart Family Study

• Published in: Environmental research Vol. 195; p. 110864
• Main Authors: Kaufman, John A., Mattison, Claire, Fretts, Amanda M., Umans, Jason G., Cole, Shelley A., Voruganti, V. Saroja, Goessler, Walter, Best, Lyle G., Zhang, Ying, Tellez-Plaza, Maria, Navas-Acien, Ana, Gribble, Matthew O.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.04.2021
• Subjects: Arizona; Arsenic - toxicity; Arsenicals; Blood Pressure; Cardiovascular diseases; Cohort study; Cross-Sectional Studies; Environmental Exposure - adverse effects; Humans; Hypertension - chemically induced; Hypertension - epidemiology; Indians, North American; Oklahoma; Prospective Studies; South Dakota; Strong Heart Study; United States; South Dakota; United States; Oklahoma; Arizona; Indians, North American; Cardiovascular diseases; Arsenicals; Strong Heart Study; Cohort study
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2021.110864

Arsenic has been associated with hypertension, though it is unclear whether associations persist at the exposure concentrations (e.g. <100 μg/L) in drinking water occurring in parts of the Western United States. We assessed associations between arsenic biomarkers and systolic blood pressure (SBP), diastolic blood pressure (DBP), and hypertension in the Strong Heart Family Study, a family-based cohort of American Indians from the Northern plains, Southern plains, and Southwest. We included 1910 participants from three study centers with complete baseline visit data (2001–2003) in the cross-sectional analysis of all three outcomes, and 1453 participants in the prospective analysis of incident hypertension (follow-up 2006–2009). We used generalized estimating equations with exchangeable correlation structure conditional on family membership to estimate the association of arsenic exposure biomarker levels with SBP or DBP (linear regressions) or hypertension prevalence and incidence (Poisson regressions), adjusting for urine creatinine, urine arsenobetaine, and measured confounders. We observed cross-sectional associations for a two-fold increase in inorganic and methylated urine arsenic species of 0.64 (95% CI: 0.07, 1.35) mm Hg for SBP, 0.49 (95% CI: 0.03, 1.02) mm Hg for DBP, and a prevalence ratio of 1.10 (95% CI: 1.01, 1.21) for hypertension in fully adjusted models. During follow-up, 14% of subjects developed hypertension. We observed non-monotonic relationships between quartiles of arsenic and incident hypertension. Effect estimates were null for incident hypertension with continuous exposure metrics. Stratification by study site revealed elevated associations in Arizona, the site with the highest arsenic levels, while results for Oklahoma and North and South Dakota were largely null. Blood pressure changes with increasing arsenic concentrations were larger for those with diabetes at baseline. Our results suggest a modest cross-sectional association of arsenic exposure biomarkers with blood pressure, and possible non-linear effects on incident hypertension. •Arsenic was positively associated with prevalent hypertension and blood pressure.•Associations were strongest in the study site with the highest exposure levels.•Blood pressure associations were stronger for participants with baseline diabetes.•Arsenic and incident hypertension had a non-monotonic relationship.