Aim: The aim of the study was to compare the prevalence of overweight, obesity, and underweight in children and adolescents from different provinces in Poland.
Materials and methods: Data from the recent, large, population-representative sample of school-aged children and adolescents (N=17573) OLAF study: "Elaboration of the reference range of arterial blood pressure for the population of children and adolescents in Poland" - PL0080 OLAF were used in the analysis. The survey was conducted in all provinces of Poland (N=16). Data were analyzed using SAS 9.2, EpiInfo 3.5.1 and LMSgrowth software packages. The frequency of overweight, obesity, and underweight were determined. For overweight and obesity (jointly) and underweight the odds ratio (OR) was calculated for gender and voivodship of residence. The body mass index (BMI) was standardized and expressed as a z-score. The statistical significance of differences between BMI z-scores depending on voivodship of residence was assessed by the t-test.
Results: Significant differences were found in the occurrence of overweight and obesity among the analysed regions, and voivodships with a lower (małopolskie, świętokrzyskie, lubelskie, and podkarpackie) and higher (mazowieckie) risk of overweight and obesity were identified. In case of underweight, łódzkie and podkarpackie (<0.040) provinces were higher risk areas, while mazowieckie (<0.001) had lower risk. The prevalence of overweight (including obesity) was higher compared to the prevalence of underweight in the majority of provinces (15 out of 16).
Conclusions: Analysis of regional differences in the prevalence of obesity, overweight and underweight in children and adolescents may point to the direction in which nationwide and local efforts should be made to reduce the inequalities stemming from nutritional status.