Objective: To evaluate low birthweight and rapid postnatal weight gain as predictors of elevated blood pressure in adolescence in a population of low socioeconomic status.
Methods: A cohort study was carried out with 208 adolescents, 78 born with low weight and 130 born with appropriate weight. The infants were followed up during the first six postnatal months and reassessed at 8 and 18 years of age. The main exposure variables were birth weight and weight gain in the first six postnatal months. Rapid weight gain was defined when above 0.67 z score. The investigated co-variables were: sex, maternal height and family income at birth, breastfeeding duration from birth to six months, nutritional status at eight years old, socioeconomic conditions, nutritional status, fat mass index and physical activity level at 18 years. The outcome variable was the occurrence of elevated blood pressure at 18 years old.
Results: The proportion of adolescents with elevated blood pressure was 37.5%. The multivariable logistic regression analysis showed the variables independently associated with a higher chance of elevated blood pressure in adolescence were rapid postnatal weight gain (OR=2.74; 95% CI 1.22-6.14; p=0.014), male sex (OR=4.15; 95% CI 1.66-40 10.38; p=0.002) and being physically active (OR=2.70; 95% CI 1.08-6.74; p=0.034).
Conclusions: The occurrence of rapid weight gain in the first six postnatal months was a predictor for elevated blood pressure in adolescence. This result highlights the influence of factors related to development in early childhood on health problems in the future.