Lifestyle intervention for children and adolescents with severe obesity - results after one year.

BACKGROUND Lifestyle interventions for children and adolescents with severe obesity show moderate short-term effects on weight reduction internationally. We evaluated treatment results at two Norwegian specialist outpatient clinics. MATERIAL AND METHOD We performed a retrospective analysis of data from children and adolescents between 3 and 18 years of age collected in 2012-2016. Children and adolescents with severe obesity who attended their one-year follow-up were included. We included in the analyses the following body weight measures: percentage overweight as defined by the International Obesity Task Force cut-off (% IOTF-25); BMI standard deviation score; waist circumference standard deviation score; and body fat percentage at the start of treatment and at one-year follow-up. RESULTS Of 568 children and adolescents who started treatment, 416 (73 %) attended the one-year check-up. A total of 271 (65 %) patients achieved a reduction in %IOTF-25, while 228 patients (55 %) reduced their BMI standard deviation score. There was a statistically significant mean reduction of all four registered body weight measurements. Altogether 54 of 325 children (17 %) changed category from severe obesity to obesity, 8 (2 %) went from severe obesity to overweight, and 8 of 91 children (9 %) changed category from obesity to overweight or normal weight. The proportion of participants with a reduction of more than 5 % in %IOTF-25 was 43 % (177/416), and a reduction in BMI standard deviation score of more than 0.25 was observed in 23 % (95/416) of participants. Girls responded on average more poorly to the intervention than boys. There was no clinically significant difference in results between the treatment centres. INTERPRETATION After one year of treatment of children and adolescents with severe obesity in two specialist healthcare centres, we found a moderate mean reduction in weight, waist circumference and body fat percentage, but with large interindividual variation.