Is the prevalence of overweight reducing at age 5-6 years? Ten years data collection in ASL Milano 2.

Background: Prevalence of overweight and obesity has been reported as high even in preschool age children. However, recent international reports suggest that prevalence is now plateauing in pediatric age. Up to now no data are available on prevalence changes in Italy in the new Millennium. Aim of the study was to describe changes of overweight and obesity prevalence during the last decade in 5-6 y children in a large Health Unit in Northern Italy.

Methods: The Health Report n 8, used at 5-6 y and containing body mass index (BMI), was utilized for prevalence estimation from 2002 to 2011 according to BMI cut-offs proposed by Cole et al.

Results: Overweight and obese children progressively decreased during the study period (p 0.0002) with a minimum observed in 2011, showing a cumulative frequency of 23.1% in 2002 and of 16.6% in 2011 (-6.5%). Mean BMI values progressively decreased with time so that BMI values in 2010-2011 were significantly lower than in 2002-2003 (p < 0.0001). Underweight subjects increased with time (p 0.013), from 8.2% in 2002 to 9.9% in 2011, but grade 3 underweight (i.e., severe thinness) did not increase during the study period. In years 2010 plus 2011, not Italians children showed higher percentages of underweight (12.5%) and overweight plus obesity (23.5%) respect to Italian peers (9.0% and 18.1%, respectively, p values <0.01 and 0.0029).

Conclusions: This is the first report suggesting a possible decrease of overweight and obesity at 5-6 y in Italy in the last decade. As the study focused only on 5-6 y children, we don't know if the true overweight prevalence in pediatric age is really reducing or the starting age of overweight status is simply delayed. The higher risk for malnutrition, both for excess or defect, found in our Area in not Italian children respect to Italian peers, strongly suggests to implement weight control especially for those children. Our finding needs further confirm studies but seems encouraging for true prevention of such condition.