Pediatric obesity in Spain: from 2000 to 2019. Comparison of two nationwide representative studies

Introduction: Monitoring childhood obesity at a national scale is essential for planning health policies. This study analyzes the two decades secular trends of pediatric weight status in Spain. Methods: Comparison of two nationwide representative cross-sectional studies: EnKid, conducted from 1998 to 2000, and PASOS from 2019 to 2020. Healthy weight, overweight, obesity, excess weight, severe obesity and abdominal obesity were estimated. Analyses were stratified by developmental stage, gender, and mother educational level. Results: From 2000 to 2019, the prevalence of abdominal obesity significantly increased from 16.0% to 22.6% (p<0.05). Girls experienced a significant rise in the prevalence of obesity: from 3.16% to 7.20% (p<0.05). The logistic regression analysis revealed a significantly higher odd ratio of excess weight (1.17, 95% CI 1.01 to 1.36; P=.043), obesity (1.43, 95% CI 1.08 to 1.90; P<.001) and abdominal obesity (1.57, 95% CI 1.31 to 1.88; P<.05) in 2019 than in 2000. Moreover, we found a strong significant increase in the likelihood of obesity (2.40; 95% CI 1.44 to 3.97; P<.01), severe obesity (4.56; 95% CI 1.07 to 19.4; P=.04) and abdominal obesity (2.48; 95% CI 1.82 to 3.37; P<.001) among girls. Finally, in 2019, lower socioeconomic status participants were also more likely to present excess weight (1.25, 95% CI 1.05 to 1.48; P<.05), obesity (1.45, 95% CI 1.07 to 1.97; P<.05), and abdominal obesity (1.65, 95% CI 1.35 to 2.02; P<.001). Conclusion: Pediatric obesity has increased in Spain over two decades. Effective health policies are urgent.