ESPE Abstracts

Introduction: Carbohydrate restriction (CH-R) in adolescents with obesity results in faster BMI reduction and glucose metabolism improvement than diets with normal carbohydrate proportion, without a higher weight regain in the short term. However, data on weight and metabolic trajectories of these patients after a more prolonged follow-up are sparse.

Objectives: To evaluate metabolic and body composition evolution during the second year of follow-up in adolescents with obesity who underwent a nutritional intervention with carbohydrate restriction for 12 months compared with patients without carbohydrate restriction (CH-N).

Patients and methods: Prospective study of 111 Caucasian adolescents (14.5±1.8 years; 64% females), with non-syndromic obesity (+4.58±1.84 BMI-SDS). At baseline, patients were randomized into two different nutritional interventions (both 1500 kcal/day): CH-R (CH supplying 10% of daily caloric intake during months 1 to 4; 30% during months 5 to 8 and 52% during months 9 to 12) vs. CH-N diet (no carbohydrate restriction [52% of total daily caloric intake]). During months 12 to 24 both groups received CH-N diet. BMI, body composition (bioimpedanciometry), glucose, insulin, lipid profile, leptin and HMW-adiponectin levels at baseline, 12 and 24 months were recorded.

Results: Both groups had similar age, BMI, body composition, metabolic features and sex distribution at baseline. At 12 months, both groups significantly reduced BMI, body fat mass, glycemia, insulinemia and leptin levels and increased HMW-adiponectin levels to a similar extent. Between 12 and 24 months, BMI-SDS (+2.94±1.71 to +3.86±2.31 SDS, P<0.001) and body fat percentage (30.9±8.9 to 33.8±9.7 %; P<0.001) increased in the CH-R group but not in CH-N group (+3.47±1.82 to +3.47±1.83 SDS and 32.8±8.5 to 32.5±7.6%, respectively). Leptin and leptin/HMW-adiponectin ratio increased only in the CH-R group (40.8±21.3 to 49.0±23.8 ng/ml and 12.0±7.9 to 16.1±11.7; P<0.01 and P< 0.001, respectively). A significant increase in fasting glucose (P<0.05) but not in insulinemia or HOMA index was observed in both groups. No significant changes in the lipid profile were observed except for LDL cholesterol levels, increasing in the CH-R (89.8±26.2 a 99.8±23. 1 mg/dl, P<0.05) but not in the CH-N group. No significant intergroup differences at 24 months were observed in any of the studied parameters.

Conclusion: Nutritional interventions base on CH-R in adolescents with obesity may be associated to a higher rate of weight regain in the middle-term, once carbohydrate restriction is stopped.