Prevalence of childhood overweight in Northwestern Spain: a comparative study of two periods with a ten year interval

OBJECTIVE: To determine the prevalence of overweight children and its modif ications over a period of 10y and whether changes in overweight prevalence is similar in the inland and coastal areas in our country. DESIGN: Cross-sectional study in two stages, the initial survey being in 19 85 and the second in 1995. SUBJECTS: 1131 children (827 and 304 from coastal and inland areas respecti vely) in the initial survey, and 903 children (695 and 208 from coastal and inland areas) in the second survey, of both sexes, aged from 6 to 15 y wer e selected by a random process from the total school population in the Prov ince of Pontevedra, North-western Spain. MEASUREMENTS: Overweight was defined in terms of body mass index (BMI), usi ng Spanish standards. Children having BMI at or above the 85th percentile w ere classed as overweight and at or above the 95th percentile as very overw eight. RESULTS: Overall prevalence of overweight and very overweight were signific antly higher in the second survey than in the first, 18.1% vs 11.7%, P < 0. 05 for overweight prevalence and 6.8% vs 2.7%, P < 0.05 for very overweight prevalence respectively. When we compared modifications in overweight prev alence over the period 10 y between the inland and coastal areas of our cou ntry, increase prevalence was observed in the inland area 9.8% vs 19.7%, P < 0.05 for initial and secondary surveys respectively, whereas in the coast al area overweight prevalence remains stable, 20.2% vs 17.6%, P > 0.05. CONCLUSION: An increased prevalence of overweight children of both sexes in over a period of 10y was observed, however, this increase was particularly caused by an increased prevalence in the inland area whereas in coastal ar ea it remained stable. We speculate that differences in overweight prevalen ce between both areas might be due to differences in physical activity asso ciated with different degrees in technological development between inland a nd coastal areas.