[Birth weight and metabolic syndrome in adults: meta-analysis].

OBJECTIVES To assess published evidences of the effect of birth weight on metabolic syndrome in adults. METHODS PubMed and LILACS databases were searched for articles published from 1966 through May 2006. The terms used were: "birth weight", "birthweight", "intra-uterine growth restriction (IUGR)", "fetal growth retardation", "metabolic syndrome", "syndrome X", "Reaven's X syndrome". Two hundred and twenty-four studies reporting estimates of the association between birth weight and metabolic syndrome or its components were considered eligible. Eleven studies provided odds ratios and were included in the meta-analysis. RESULTS All but two studies reported an inverse relationship between birth weight and metabolic syndrome. A comparison between low birth weight vs. normal birth weight subjects showed the random effects odds ratio for metabolic syndrome was 2.53 (95% CI: 1.57;4.08). The funnel plot graphic suggests a publication bias but, even in the studies with more than 400 subjects, the results remained significant (pooled odds ratio: 2.37 (95% CI: 1.15;4.90). CONCLUSIONS Low birth weight increases the risk of metabolic syndrome in adults.