GROWTH SECULAR TREND DURING EARLY CHILDHOOD IN NORTHERN SPAIN

Objective: To check whether secular changes exist in growth pattern of caucasic children from the North of Spain up to 2 years of age compared with 25-30 years ago population growth curves. Material and methods: Longitudinal study of a representative cohort of caucasic infants born a term in Aragon (n = 1.099). Standard deviation scores (z-scores) for weight, length and body mass index (BMI) have been calculated by two available 25-30 years ago population growth curves (Sobradillo et al. and Ferrandez et al.). Results: At all ages, weight, length and BMI mean z-scores significantly vary depending on the growth standard curve used (p <= 0.001). At birth, weight z-score is - 0.36 (95% CI: -0.42; -0.30) according to Sobradillo et al. and -0.26 (95%CI: -0.29; 0.33) according to Ferrandez et al. These differences decreased progressively becoming minimum at 2 years (mean weight z-score -0.08 and -0.05; respectively). At this age, length mean z-score is +0.54 (95 %CI: 0.48; 0.61) according to Sobradillo et al. and +0.19 (95% CI: 0.12; 0.25) according to Ferrandez et al. Mean BMI z-scores of our sample showed lower values than selected standards. Conclusions: Current birth weight of caucasic infants from Northern Spain is lower than in the previous generation. At 2 years of age there is a trend of increasing length, with a similar weight, resulting in lower BMI values.