Rapid growth in infancy and childhood and obesity in later life--a systematic review.

The association between obesity and morbidity resulting from chronic diseases is well known. This systematic review addresses studies of the role of rapid growth in infancy and childhood as possible determinants of overweight and obesity later in the life course. We reviewed MEDLINE for studies reporting on growth in infancy and childhood, as well as measures of weight or adiposity in later childhood, adolescence or adulthood. The methodological quality of the papers was assessed using the criteria suggested by Downs and Black. Sixteen articles that fulfilled review criteria were located. There was wide variability in the indicators used for defining rapid growth as well as overweight or obesity. The age range in which weight or adiposity was measured ranged from 3 to 70 years. In spite of differences in definitions used, 13 articles that reported on early rapid growth found significant associations with later overweight or adiposity. Efforts should be made to standardize the definition of rapid growth, as well as that of overweight and obesity in children and adolescents. The most frequent definition for rapid growth in this review was a Z-score change greater than 0.67 in weight for age between two different ages in childhood. Regarding obesity, the definition proposed by the International Obesity Task Force also appears to be most appropriate. The present results indicate that early growth is indeed associated with the prevalence of obesity later in the life course.

Birth size, early childhood growth, and adolescent obesity in a Brazilian birth cohort.

DESIGN: Cross-sectional visit to a subsample of a population-based birth cohort. SAMPLE: A total of 1076 adolescents aged 14-16 y; 51% males. MEASUREMENTS: Weight, height, subscapular and triceps skinfolds were used for assessing overweight and obesity in adolescence, using WHO-recommended criteria. Anthropometric status in early life was measured through birthweight and through weight and length/height at average ages of 20 and 43 months. RESULTS: All analyses were adjusted for socioeconomic and maternal confounding factors. Birthweight and attained size (Z-scores of weight-for-age, height-for-age and weight-for-height) at 20 and 43 months were associated linearly and positively with overweight and obesity in adolescence. Four in each five obese adolescents were not overweight in childhood. Rapid weight gain, both between birth and 20 months, and between 20 and 43 months, was also associated with adolescent overweight and with obesity. Rapid height gain between 20 and 43 months was associated with overweight only. Most associations were stronger for boys. CONCLUSIONS: Birth size, attained size in childhood and particularly growth velocity in early life were associated with increased prevalence of obesity and overweight in Brazilian adolescents. On the other hand, the vast majority of overweight or obese adolescents were not overweight children. Early interventions are undoubtedly important, but population-based strategies aimed at improving diets and physical activity appear to have greater long-term potential than measures targeted at overweight children.

[Diagnosis of overweight in adolescents: comparative study of the performance different criteria for body mass index]. / Diagnóstico de sobrepeso em adolescentes: estudo do desempenho de diferentes critérios para o Indice de Massa Corporal.

OBJECTIVE: In an attempt to simplify the screening process for detecting obesity in adolescence, the performance of different cutoff values for body mass index (BMI) was assessed in a population-based cohort in Southern Brazil. METHODS: A total of 493 adolescents aged 15-16 years who lived in the city of Pelotas, Brazil, were studied. Obesity was defined according to the WHO criteria taking into account age and sex (a BMI equal to or greater than the 85th percentile of the NHANES I reference, plus subscapular and triceps skinfold equal to or greater than the 90th percentile of the same reference). Different BMI cutoff values were used to assess their specificity and sensitivity. RESULTS: For boys, BMI>/=25 kg/m(2) showed the best performance for detecting obesity, with a sensitivity of 90% and only 5% of false positives. The Brazilian proposed criteria that was used had 100% sensitivity but up to 23% of false positives. Higher cutoff values were also tested, but there was a slight increase in specificity, accompanied by a marked reduction in sensitivity. CONCLUSIONS: The BMI cutoff of 25 kg/m(2) presented the best performance for screening obesity in the studied sample, and it is recommended for adolescents aged 15 and more in populations with similar characteristics. It provides a single cutoff value to be used in primary health services, eliminating the need for age and sex-specific values and skinfold measurements, and it is also consistent with the cutoff value proposed to identifying overweight adults.