Linear catch-up growth does not increase the risk of elevated blood pressure and reduces the risk of overweight in males

OBJECTIVES: To analyse if size at birth is associated with blood pressure and body mass index (BMI) at conscription in males, and if linear catch-up growth in height modifies these associations. DESIGN: A population-based cohort study of 276 033 single-born males aged 17-24. Information from the Swedish Birth Register was individually linked to the Swedish Conscript Register. Systolic blood pressure was standardized for final height. RESULTS: Compared to males not being small for gestational age at birth, males being light for gestational age [<-2 standard deviation scores (SDS)] were at increased risk of high systolic blood pressure [odds ratio (OR) 1.33; 95% confidence intervals (CI) 1.20-1.46], and a short adult stature was associated with a further increased risk [OR 1.65 (CI 1.13-2.40)]. Being born short for gestational age (<-2 SDS) was associated with a slightly increased risk of high systolic blood pressure [OR 1.16 (CI 1.04-1.29)], and linear catch-up growth in height did not increase this risk. Males born short for gestational age, who also were short at conscription, had an increased risk of a high BMI [OR 1.65 (CI 1.25-2.19)]. CONCLUSIONS: Males born light for gestational age have an increased risk of high systolic blood pressure, especially if they end up with short adult stature. Being born short for gestational age is associated with a slightly increased risk of high systolic blood pressure, and catch-up growth is not associated with a further risk. Lack of catch-up growth is, among males born short for gestational age, associated with an increased risk of overweight.