Background: Heart failure is a major contributor to morbidity and mortality in the United States. Arsenic, a ubiquitous element, found in drinking water, rice, flour and other grains, has been shown to play a role in the development of arrhythmias and coronary heart disease through vascular endothelial dysfunction and free radical injury. Studies have shown that arsenic induces interstitial myocardial fibrosis and we hypothesize that this may contribute to the development of heart failure.
Methods: We conducted an analysis of the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Urinary arsenic was evaluated as a combination of inorganic arsenic, and methylated arsenic species (Monomethylarsonic acid and Dimethylarsinic acid) in microgram per gram of urine creatinine. We used a logistic regression model to evaluate the relationship between quartiles of urinary arsenic and heart failure while controlling for confounders. Analyses were conducted using SAS survey procedures and data evaluated at α=0.05.
Results: The total number of study participants were 2065 adults with the mean age of 40.2 years, approximately half were male (48.8%) and 64.1% were white. There was no significant association between urinary arsenic measures and incidence of heart failure. Persons with high arsenic levels (>75th percentile) were less likely to develop heart failure after controlling for confounders.
Conclusion: Our results show a statistically significant decrease in the odds of developing heart failure among persons with high arsenic levels (>24ug/g). This is in contrast to other studies, which have shown high arsenic levels to have a toxic effect on the heart. Limitations of our study include the inability to determine the chronicity of exposure and exclude persons with increased levels of organic arsenic from seafood, which are nontoxic. Additional observational and prospective studies are needed to further evaluate this association.