Association of Early Life Arsenic Exposure with Prehypertension in Adolescents and Young Adults in Rural Bangladesh

Abstract

Background: Evidence suggests that prolonged exposure to arsenic through drinking water increases the risk of hypertension in adults. However, few studies have evaluated the impact of early life arsenic exposure on blood pressure in adolescents and young adults. This study aimed to assess the association between in-utero-and-childhood arsenic exposure and prehypertension among the participants aged 11 to 22 years.Methods: The study was conducted in rural Bangladesh, Matlab. A cohort of 200 adolescents and young adults were enrolled of which 107 had in utero and first five years exposure to water arsenic concentration over 400µg/L (exposed group) and 93 had less than 10 µg/L(unexposed group). Blood pressure was measured using a standard mercury sphygmomanometer with an appropriately sized cuff. Prehypertension in adolescents was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) between the 90th and 95th percentile for age, sex and height. For the subjects 18 years and above, prehypertension was defined as SBP ranging from 120-139 mmHg and/or DBP 80-89 mmHg.Results: The overall prevalence of prehypertension was 16.5%. The high exposure group had a higher prevalence of prehypertension compared to the low exposure group (20.6% vs. 11.8%, 1-tailed p = 0.049). After adjustment for potential confounders, the prevalence odds ratio (POR) for prehypertension was 2.3 [95% Confidence Interval (CI): 0.78-7.1, 1-tailed p=0.066] in the participants exposed to arsenic >400 µg/L in their early life. The increased prevalence of prehypertension was only evident in females (POR=8.8, 95% CI: 1.05-74.1, 1-tailed p=0.023), and not in males (POR= 1.1, 95% CI: 0.26-5.1, 1-tailed p=0.433).Conclusions: Our result suggests a possible effect of early life arsenic exposure on increased risk of prehypertension in females. We plan to follow this unique cohort to see if the effect on blood pressure persists in females as they grow older.