Bae S, Hong YC. Exposure to bisphenol A from drinking canned beverage increases blood pressure: randomized crossover trial. Hypertension. 2015;65(2):313-319. Epub 2014 Dec 8.
Randomized crossover trial
The trial involved 60 volunteers from a community center in Seoul, South Korea. The participants were older than 60 years of age, and the mean age was 73.1+4.2 years. The participants were mostly women with only 4 male participants. The study excluded those with a medical history of heart disease, cancer, liver disease, or endocrine disease. Among the participants, 27 reported hypertension and 9 had diabetes mellitus. Of the patients with hypertension, 1 participant received medication. All diabetic patients were being treated for this condition.
The participants visited the study site on 3 separate occasions with more than 1-week intervals between each visit. All participants fasted for more than 8 hours before visiting the study site at 9 AM. They were randomized to drink soymilk in 1 of 3 different container combinations each time: 2 glass bottles, 2 cans, or 1 can and 1 glass bottle. The participants did not eat or drink any other food for 2 hours after consuming the soymilk. Urinary bisphenol A (BPA) concentration, blood pressure, and heart-rate variability were measured 2 hours after each consumption.
The study found that participants who drank from cans lined with BPA had increased urinary BPA concentrations of more than 1600% and increased systolic blood pressure by 4.5 mmHg as compared with participants who drank from glass bottles. There was no statistically significant difference in heart-rate variability between the study groups.
This study asserts that a 1-time exposure to BPA acutely increases systolic blood pressure. This is consistent with previous epidemiological studies that have shown a positive association of BPA concentration and blood pressure.1-3 The concentration of BPA measured in the cans was 8.22+0.82 µg/L compared with 0.31+0.01 µg/L in the glass bottles. In previous epidemiological studies, cumulative BPA exposures— greater than 1 week in 1 study and over 5 consecutive days in another—linked increased BPA concentration in the urine with cardiovascular disease (CVD).4,5
In patients with elevated blood pressure, clinicians need to consider bisphenol A as an underlying contributor and inquire about sources of exposure.
The findings of the present study have significant clinical implications because BPA could be an underlying contributor to hypertension. BPA is generally not considered or evaluated in the clinical setting as a risk factor for CVD. A single exposure to a beverage containing BPA significantly elevated blood pressure, which means that patients who have repeated exposures over time drinking from multiple cans and plastic bottles or eating canned food products may be inadvertently increasing their risk for heart disease and peripheral arterial disease. Despite BPA’s rapid metabolism and clearance, it is a known endocrine-disruptor whose accumulation has adverse effects on the reproductive and/or endocrine systems.6
In patients with elevated blood pressure, clinicians need to consider BPA as an underlying contributor and inquire about sources of exposure. Inquiries into whether patients eat canned soup, drink from plastic or polycarbonate containers, consume packaged foods, or handle receipts lined with BPA can reveal an underlying contributor to blood pressure.7,8 Reducing exposure to BPA and encouraging its avoidance can lead to improved outcomes in hypertensive and CVD patients.