title: Factors associated with height catch-up and catch-down growth among schoolchildren.
abstract: In developed countries, children with intrauterine growth restriction (IUGR) or born preterm (PT) tend to achieve catch-up growth. There is little information about height catch-up in developing countries and about height catch-down in both developed and developing countries. We studied the effect of IUGR and PT birth on height catch-up and catch-down growth of children from two cohorts of liveborn singletons. Data from 1,463 children was collected at birth and at school age in Ribeirão Preto (RP), a more developed city, and in São Luís (SL), a less developed city. A change in z-score between schoolchild height z-score and birth length z-score ≥ 0.67 was considered catch-up; a change in z-score ≤ -0.67 indicated catch-down growth. The explanatory variables were: appropriate weight for gestational age/PT birth in four categories: term children without IUGR (normal), IUGR only (term with IUGR), PT only (preterm without IUGR) and preterm with IUGR; infant's sex; maternal parity, age, schooling and marital status; occupation of family head; family income and neonatal ponderal index (PI). The risk ratio for catch-up and catch-down was estimated by multinomial logistic regression for each city. In RP, preterms without IUGR (RR = 4.13) and thin children (PI<10(th) percentile, RR = 14.39) had a higher risk of catch-down; catch-up was higher among terms with IUGR (RR = 5.53), preterms with IUGR (RR = 5.36) and children born to primiparous mothers (RR = 1.83). In SL, catch-down was higher among preterms without IUGR (RR = 5.19), girls (RR = 1.52) and children from low-income families (RR = 2.74); the lowest risk of catch-down (RR = 0.27) and the highest risk of catch-up (RR = 3.77) were observed among terms with IUGR. In both cities, terms with IUGR presented height catch-up growth whereas preterms with IUGR only had height catch-up growth in the more affluent setting. Preterms without IUGR presented height catch-down growth, suggesting that a better socioeconomic situation facilitates height catch-up and prevents height catch-down growth.
authors.affiliation: Departamento de Saúde Pública, Universidade Federal do Maranhão, São Luís, Maranhão, Brasil.
authors.forename: Rosângela F L
authors.initials: RF
authors.lastname: Batista
authors.forename: Antônio A M
authors.initials: AA
authors.lastname: Silva
authors.forename: Marco A
authors.initials: MA
authors.lastname: Barbieri
authors.forename: Vanda M F
authors.initials: VM
authors.lastname: Simões
authors.forename: Heloisa
authors.initials: H
authors.lastname: Bettiol
mesh_terms: D000704:Analysis of Variance; D001827:Body Height / Q000502:physiology*; D001938:Brazil; D002648:Child; D002657:Child Development / Q000502:physiology*; D003906:Developing Countries; D005260:Female; D005317:Fetal Growth Retardation; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development*; D016015:Logistic Models; D008297:Male; D012959:Socioeconomic Factors