A 13-YEAR FOLLOW-UP STUDY OF TREATED OBESE CHILDREN IN JAPAN

The purpose of this study was to evaluate the tracking of body weight from childhood to adulthood in obese Japanese children treated for childhood obesity. The sample consisted of 276 subjects (age: 23.9 ± 4.1) who responded to a mailed questionnaire in 1998 among 1,047 children (age: 10.6 ± 2.2) who had been treated for obesity between 1976 and 1992. Based on height and weight from medical records, the relative weight (RW) was calculated and children were classified as follows: slight obesity (n = 17), moderate obesity (n = 131), or severe obesity (n = 128). Adulthood BMI was defined as normal, overweight, or obese according to the WHO/NIH criteria. Childhood obesity (RW ≥ 120%) tracked into adulthood obesity or overweight (BMI ≥ 25) in 54.7% of all cases. Severely obese children tracked into adulthood obesity at a frequency about double that of moderately obese children (36.7% of severe vs. 16.8% of moderate obesity, P < 0.0001). However, 58.8% of moderately and 26.6% of severely obese children achieved normal BMI levels in adulthood. Among the severely obese children who became normal weight adults, the prevalence of chronic diseases was about one fifth of those who became obese adults (P = 0.041). The treatment of severe obesity in children should be a priiority, since they have a higher risk for adult obesity. Treating childhood obesity and preventing obesity in adult life may decrease the risk for adult chronic diseases.