O4-1.3 Overweight in short and tall children

Abstract

Introduction It is known that body mass index is correlated with height. This suggests that the prevalence rates of overweight and obesity differ between tall and short children. Our aim is to study the impact of height during childhood on the national prevalence rates of overweight and obesity at childhood and adulthood. Methods We used cross-sectional growth data from the previous two Dutch nationwide surveys performed in 1997 (n=14 500) and 2009 (n=10 129) and longitudinal data from birth to 18 y (n=708). We selected children from 2 to 10 y (before onset of puberty) from the two surveys. Overweight (including obesity) and obesity were calculated by cut-offs for body mass index (kg/m 2 ) according to International Obesity Task Force. Short was defined as +1SD. Results In 1997, the prevalence rates of childhood overweight and obesity were respectively 5.1% and 0.8% in short children, and 17.0% and 3.0% in tall children. In 2009, these figures were 6.9% and 1.1% in short children, and 22.9% and 5.5% in tall children. The RRs of childhood overweight and obesity of tall vs short children were respectively 3.3 (95% CI 2.6 to 4.2) and 4.4 (95% CI 2.4 to 7.9). However, these RRs were lower at adulthood, respectively 1.3 (95% CI 0.5 to 3.7) and 1.5 (0.98 to 2.2). Conclusion There is a height bias in the prevalence of overweight and obesity. Correcting for height gives better insight into (inter)national comparisons and secular trends of overweight and obesity at childhood. We will present the figures and methodological explanation of the height bias.