Relevance of the choice of growth charts in the diagnosis of overweight and obesity

Objectives: to estimate the differences in prevalence of obesity and overweight in our population using different growth charts.

Methods: population based, descriptive, cross-sectional study. Overweight or obesity were diagnosed by comparing the BMI of 8905 children aged 6, 10 and 13 with the cut-off points established by the following charts: Orbegozo Foundation 1988, 2004 and 2011; International Obesity Task Force 2012; WHO 2007; and Spanish cross-sectional study 2008.

Results: the Spanish cross-sectional study 2008 chart provided the lowest prevalence for all ages (2.8% [CI 95%: 2.3 to 3.4] at 6 years, 2.2% [CI 95%: 1.7 to 2.8] at 10 years and 2.2% [CI 95%: 1.6 to 2.8] at 13 years). The WHO 2007 chart provided the highest prevalence of obesity at 6 years (10.6% [CI 95%: 9.6 to 11.6]) and the Orbegozo Foundation 1988 chart for other age groups (15.4% [CI 95%: 14.1 to 16.6] at 10 years and 12.4% [CI 95%: 11 to 13.7] at 13 years). Regarding overweight, the results were also discordant. The WHO 2007 chart had the highest prevalence while Orbegozo Foundation 1988 had the lowest.

Conclusions: the prevalence of overweight and obesity varies significantly according to the different growth charts. We should know the growth charts we use to contextualize the results. Data on the prevalence of obesity and overweight should always be accompanied by the chart used because otherwise the values ​​are meaningless.