Objective: To assess the validity of self-reported height and weight by parents of 4-year-old children and subjective weight perception.Design: Descriptive cross-sectional study.Setting: Paediatric population living in the Autonomous Community of Madrid.Participants: Children born in 2008–2009 examined at 47–59 months of age. Data were collected by paediatricians of the Madrid Primary Care Physicians Sentinel Network. Parents reported weight and height data. Prevalence of weight status categories was calculated using WHO and International Obesity Task Force (IOTF) reference criteria. Sensitivity, specificity and positive predictive value (PPV) were estimated. The appraisal of their child’s weight perception and parental misperception were assessed.Results: For 2914 children, reported height was underestimated by −1·38 cm, weight by −0·25 kg and BMI was overestimated by +0·41 kg/m²on average. The prevalence of obesity estimated with reported data was 2·7 times higher than that calculated with measured data (16·2v. 6·0 %) according to WHO classification, and 3·6 times higher with IOTF classification. Sensitivity to identify obesity was 70·5 %, specificity was 87·3 % and PPV was 26·2 % (WHO classification). Half of the parents of pre-schoolers with obesity failed to identify their child’s weight status. Parental misperception among children classified as having overweight or obesity reached 93·0 and 58·8 %, respectively.Conclusions: Parents underestimated children’s height and weight, leading to an overestimation of the prevalence of obesity. Small inaccuracies in reported measures have an important effect for the estimation of population prevalences. Parents’ report of child weight status is unreliable. Parental awareness and acknowledgement of child weight status should be improved.

Objectives: To evaluate the association of general and abdominal obesity with high blood pressure in young children. Methods: A longitudinal study including 1796 participants from the Madrid region (Spain) with baseline at age 4 years and a follow-up 2 years later. Blood pressure, body mass index and waist circumference were measured during a physical examination. We evaluated the association between obesity at baseline and weight changes between the ages of 4 and 6 years and high blood pressure. Data were analysed using linear and logistic regressions adjusted for covariates. Results: Obese 4 year olds (general or abdominal obesity) experienced an average 4–5 mmHg increase in systolic blood pressure and a 2.5–3 mmHg increase in diastolic blood pressure by the age of 6 years. Compared to children maintaining a non-excess weight (based on body mass index) during follow-up incident and persistent cases of excess weight (overweight or obesity) had an odds ratio (OR) for high blood pressure of 2.49 (95% confidence interval (CI) 1.50–4.13) and OR 2.54 (95% CI 1.27–5.07), respectively. Regarding abdominal obesity we estimated OR 2.81 (95% CI 0.98–8.02) for incident cases and OR 3.42 (95% CI 1.38–8.49) for persistent cases. Similar estimates for the waist–height ratio were observed. Individuals who experienced remission to non-excess weight did not have an increased risk of high blood pressure. Conclusions: We observed an increased risk for high blood pressure among 4-year-olds who presented with persistent or incident cases of excess weight (body mass index) or abdominal obesity after 2 years of follow-up. Children with excess weight or obesity at baseline who remitted to non-excess weight did not exhibit an increased risk of high blood pressure.

Objectives To evaluate the association between excess weight and the demand of health services in preschool children compared with healthy weight. Methods The data come from the Longitudinal Study of Childhood Obesity cohort (1884 4-year-old children, residing in the Madrid region, Spain) who provided information through telephone questionnaire, physical examination and electronic medical records. We defined overweight, general and abdominal obesity based on body mass index, waist circumference and waist-to-height ratio. Using mixed models of multivariable negative binomial regression we calculated the incidence rate ratio (IRR) regarding primary care (PC) doctor visits, drug prescriptions and hospital admissions by weight status at the end of the 2-year follow-up. Results Childhood general obesity was associated with a higher demand for PC services related to psychological problems (IRR=1.53; 95% CI 1.02 to 2.28) and childhood abdominal obesity, according to waist-to-height ratio, was related to more frequent problems of the musculoskeletal system (IRR=1.27; 95% CI 1.00 to 1.62). Drugs were prescribed more frequently to children falling under all three definitions of excess weight, compared with healthy weight children. No differences in the number of hospital admissions were observed. Conclusions The demand of health services related to early childhood obesity was small. Nevertheless, obesity was associated with a slightly greater demand for drug prescriptions and for PC doctor visits related to psychological and musculoskeletal problems.