Early and late growth and blood pressure in adolescence

Objective: To assess the effect of growth during infancy and childhood on blood pressure in adolescence. Design: Birth cohort study. Setting: Pelotas, southern Brazil, Participants: 749 adolescents with complete information on birth weight and gestational age, as well as on anthropometric data at all three follow up visits (mean age 20 months, 42 months, and 15 years). Main outcome measurements: Systolic and diastolic blood pressure at adolescence. Results: After controlling for possible confounding variables, birth weight was negatively associated with systolic blood pressure, one unit increase in standard deviation score of birth weight for gestational age was associated with a decrease of 1.23 mm Hg (95% confidence intervals -2.03 to -0.43) in systolic blood pressure. Weight for age z score at the age of 15 years showed a strong positive association with systolic blood pressure, one unit increase in standard deviation score of birth weight for gestational age was associated with an increase of 4.4 mm Hg (95% confidence intervals 3.50 to 5.3). Diastolic blood pressure was not associated with birth weight. For adequate for gestational age infants, the positive association between weight in adolescence and blood pressure became stronger when previous weights were added to the model. Conclusion: This study showed that early-as well as-late catch up growth is associated with increased systolic blood pressure in adolescence, whereas only late catch up is related with diastolic blood pressure. These findings suggest that catch up growth, irrespective of age, is associated with increased blood pressure in adolescence.