Childhood growth and adult hypertension in a population of high birth weight

Low birth weight has consistently been associated with increased adult blood pressure. The relative importance of childhood growth is, however, less well established. This study examined sex-specific associations between childhood growth and adult blood pressure in 2120 subjects born from 1921 to 1935 in Reykjavik who were recruited into a longitudinal study in 1967-1991. Size at birth and growth at regular intervals between 8 and 13 years were collected from national archives. Hypertensive males did not differ from normotensive males at birth but were increasingly taller and of higher body mass index between 8 and 13 years. No differences in adult height were observed between hypertensive and normotensive males. For boys, growth-velocity (change in growth per year) for body mass index and height between 8 to 13 years was positively associated (P<0.05) with adult blood pressure. The association for body mass index-velocity was fully accounted for by concurrent body size, whereas height-velocity was independent of birth weight and concurrent body size. Males in the highest compared with the lowest tertile in the height-velocity distribution had 66% increased risks of hypertension (95% CI: 15% to 139% increased risks of hypertension) corresponding with 5.0 mm Hg increase (95% CI: 1.5 to 8.5 mm Hg increase) and 3.1 mm Hg increase (95% CI: 1.1 to 5.0 mm Hg increase) in systolic and diastolic blood pressures, respectively. Hypertensive females weighed less at birth but did not differ markedly from normotensive girls between 8 and 13 years, and no association was observed for growth-velocity. In conclusion, rapid linear growth between 8 and 13 years predicts elevated adult blood pressure in boys. This association is likely to reflect relatively early onset of puberty among hypertensive males.