Obesity is Associated with Higher Blood Pressure and Higher Levels of Angiotensin II but Lower Angiotensin-(1-7) in Adolescents Born Preterm.

OBJECTIVES: To evaluate if obesity is associated with increased angiotensin II (Ang II) and decreased angiotensin-(1-7) or Ang-(1-7) in the circulation and urine among adolescents born prematurely. STUDY DESIGN: In a cross-sectional analysis of 175 14-year-olds born preterm with very low birth weight, we quantified plasma and urinary Ang II and Ang-(1-7) and compared their levels between subjects with overweight/obesity (body mass index ≥85th percentile, n = 61) and those with body mass index <85th percentile (n = 114) using generalized linear models, adjusted for race and antenatal corticosteroid exposure. RESULTS: Overweight/obesity was associated with higher systolic blood pressure and a greater proportion with high blood pressure. After adjustment for confounders, overweight/obesity was associated with an elevated ratio of plasma Ang II to Ang-(1-7) (ß: 0.57, 95% CI 0.23-0.91) and higher Ang II (ß: 0.21 pmol/L, 95% CI 0.03-0.39) but lower Ang-(1-7) (ß: -0.37 pmol/L, 95% CI -0.7 to -0.04). Overweight/obesity was associated with a higher ratio of urinary Ang II to Ang-(1-7) (ß: 0.21, 95% CI -0.02 to 0.44), an effect that approached statistical significance. CONCLUSIONS: Among preterm-born adolescents, overweight/obesity was associated with increased Ang II but reduced Ang-(1-7) in the circulation and the kidney as well as higher blood pressure. Obesity may compound the increased risk of hypertension and cardiovascular disease in individuals born prematurely by further augmenting the prematurity-associated imbalance in the renin-angiotensin system.

Preterm Birth Is Associated with Higher Uric Acid Levels in Adolescents.

OBJECTIVE: To compare serum uric acid levels in adolescents born prematurely and adolescents born at term and to assess the correlation between serum uric acid and blood pressure (BP) in those born prematurely. STUDY DESIGN: In this observational cohort study, 124 adolescents born prematurely and 44 adolescents born at term were studied at 14 years of age. Multivariate analyses were used to describe the relationship of premature birth to serum uric acid while adjusting for confounding variables. Pearson correlation was used to describe the relationship between uric acid and systolic BP among those born prematurely. RESULTS: Adjusting for race, sex, maternal hypertension, and fetal growth, we found that preterm adolescents had greater serum uric acid levels than adolescents born at term (adjusted mean difference 0.46, 95% CI 0.10-0.81 mg/dL; 27.4, 6-48.2 µmol/L; P = .012). Among those born prematurely, uric acid was positively correlated with systolic BP (Pearson correlation coefficient: 0.29, 0.12-0.44; P = .0013). CONCLUSIONS: Serum uric acid levels are greater in adolescents born prematurely than in those born at term, and this difference could contribute to greater BP among individuals born prematurely.

Pesticide Use and Safety Training in Mexico: The Experience of Farmworkers Employed in North Carolina.

Migrant and seasonal farmworkers in the United States are now overwhelmingly immigrants from Mexico. Pesticide exposure among these farmworkers is a major occupational health concern; however, little research has considered the agricultural pesticide use and safety experiences of these workers in their communities of origin. This analysis uses survey data collected by the PACE project to delineate the farming and pesticide use experiences of Mexican-born farmworkers in North Carolina. Over 80 percent of the 277 Mexican-born farmworkers had done agricultural work in Mexico, including work on their own farms (93%) and as hired farm labor (35%). Almost two-thirds of those farmworkers with farming experience had used pesticides, but only about one-third of those who used pesticides had received pesticide safety training or information. Most of those who used pesticides had used some form of safety equipment. Those who had worked as hired farm labor in Mexico were more likely to have used pesticides and safety equipment, and to have received safety training and information. Those who spoke an indigenous language at home rather than Spanish were less likely to have used pesticides and to have received safety training and information. These results demonstrate that farmworkers coming to the U.S. from Mexico arrive with a variety of experiences with pesticide usage and pesticide safety training. Such experiences form the framework within which farmworkers understand the relationship of pesticide usage to human health. It is important for occupational health and safety programs directed to farmworkers in the U.S. to consider the experiences these workers bring from their communities of origin.