Growth in terms of length of Chilean infants of low socioeconomic status: 1978-1992
Pizarro, F.; Olivares, M.; Hertrampf, E.; Walter, T.
Archivos latinoamericanos de nutricion 46(2): 107-112
1996
ISSN/ISBN: 0004-0622 PMID: 9239286 Document Number: 465171
In Chile infant malnutrition is better reflected by the length/age indicator than by weight/length. In this study we will present the progression of length during the first year of life from the year 1978 through 1992 of infants of low socioeconomic status. We selected healthy infants with > 3000 g birth weight and birth length > 0.5 z. According to type of milk feedings they were defined as CM (cow milk) those who were weaned before 4 months of life and EM (exclusive breast milk) those who continued exclusive breast milk (as only source of milk solids permitted) past 6 months. Infants CM of the 1978-80 cohort had a length at birth z +0.21 reaching 1 year with z -0.65, a loss of 0.86 z. Infants from the cohorts of 1982-86 and 1988-92 fell from z +0.15 to z -0.37 (a loss of -0.52 z) and +0.16 to -0.19 (a loss of -0.45 z) between birth and 12 months respectively. EBM infants length also fell significantly (delta z: -1.12, -0.69 and 0.59 respectively). Proteincalorie nutrition was adequate confirmed with weight/age or length/weight curves with means of +0.52 throughout the first year. Analysis of the length curves by regression shows that the slopes of the 3 cohorts are significantly different (< 0.01) for CM and EBM favoring the most recent cohorts. Multiple regression analysis identified association of length at 1 year with birth weight (p < 0.05), birth length (p < 0.01) and socioeconomic index (p < 0.01). We suggest that there is an improvement in the trend of Chilean infants growth in length for the past 20 years, likely due to improvement in socioeconomic level.