Body mass index patterns over 5 y in obese children motivated to participate in a 1-y lifestyle intervention: age as a predictor of long-term success.
BACKGROUND
Long-term outcome after lifestyle interventions in obese children is largely unknown but important to improving intervention.


OBJECTIVE
The aim was to identify predictors of long-term changes in body mass index (BMI) after lifestyle intervention.


METHODS
Annual changes in the BMI SD score (BMI-SDS) over 5 y in 663 obese children (aged 4-16 y) motivated to participate in an outpatient lifestyle intervention were analyzed. Child-specific longitudinal curves based on multilevel growth curve models (MLMs) over 5 y were estimated depending on patient characteristics (age and sex).


RESULTS
The mean decrease in BMI-SDS was 0.36 (95% CI: 0.33, 0.39) at the end of the 1-y intervention and 0.46 (95% CI: 0.36, 0.55) 4 y after the intervention. Change in BMI-SDS in the intervention period predicted long-term outcome after 5 y (P < 0.001). MLMs identified age but not sex as a predictor of the outcome: the youngest children (<8 y) at the onset of the intervention had the greatest decrease in BMI-SDS over 5 y, and the oldest children (>13 y) had the least decrease in BMI-SDS (P < 0.05). Whereas there was a larger reduction in BMI-SDS during the intervention in children aged 8-10 y than in children aged 11-12 y, long-term decrease in BMI-SDS was greater in 11-12-y-old children (P < 0.001).


CONCLUSIONS
Younger age was associated with the best long-term outcome after participation in the lifestyle intervention, which supports the need for early intervention in childhood obesity. Children aged 8-10 y may need modified intervention, because BMI-SDS increased more in the older children in the long term. However, mean BMI-SDS was significantly lower 4 y after the end of the intervention than at baseline in all age groups. This study was registered at clinicaltrials.gov as NCT00435734.
Reinehr
Thomas
T
Vestische Kinderklinik Datteln, Institute of Pediatric Nutrition Medicine, University of Witten-Herdecke, Datteln, Germany. t.reinehr@kinderklinik-datteln.de
Kleber
Michaela
M
Lass
Nina
N
Toschke
André Michael
AM
D000293:Adolescent; D000367:Age Factors; D001521:Behavior Therapy; D001823:Body Composition; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D015444:Exercise; D005081:Exercise Therapy; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D009042:Motivation; D009765:Obesity / Q000503:physiopathology* / Q000523:psychology*; D010352:Patient Dropouts; D011613:Psychotherapy; D013997:Time Factors; D055105:Waist Circumference