medwireNews: Most obese adolescents who undergo bariatric surgery still have significant weight loss 3 years after the procedure, show the results of the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study.

And the weight reduction was accompanied by the resolution of obesity-related comorbidities such as hypertension, Type 2 diabetes and abnormal kidney function, the researchers report in The New England Journal of Medicine.

However, they caution: “These benefits must be viewed in the context of the risks of micronutrient deficiencies and the possibility that future abdominal procedures will be needed in some patients.”

The proportion of patients with low ferritin levels increased from 5% at baseline to 57% at 3 years, while levels of vitamin A and B12 also significantly declined.

This highlights the importance of long-term nutritional follow-up and adequate supplementation, say Thomas Inge (Cincinnati Children’s Hospital Medical Center, Ohio, USA) and study co-authors.

Over the 3 years after surgery, 30 (13%) of the 228 patients required 47 additional intra-abdominal procedures, most commonly cholecystectomy (18 procedures), but also gastrostomy, lysis of adhesions, exploratory laparotomy and hernia repair, among others. All but three of the procedures were thought to be related to the bariatric surgery (gastric bypass in 161 patients and sleeve gastrectomy in 67).

The patients were aged between 13 and 19 years at baseline and had an average body mass index (BMI) of 53 kg/m2. All were obese (BMI>30 kg/m2) at baseline, but by 3 years 26% were no longer in this category.

At 3 years, 89% of patients who underwent gastric bypass and 85% of those who underwent sleeve gastrectomy had at least a 10% reduction in their BMI, with this having remained fairly stable since 1 year after surgery. However, a respective 2% and 4% of patients increased their BMI from baseline.

The baseline prevalence of obesity-related comorbidities ranged from 10% for prediabetes to 76% for dyslipidaemia, and the rates of resolution at 3 years ranged from 66% for dyslipidaemia to 95% for Type 2 diabetes.

The researchers say that the resolution rates for diabetes and for hypertension (74%) are higher than reported for adults after bariatric surgery, which “leads us to hypothesize that adolescents may have a greater potential than adults for reversal of the cardiometabolic consequences of obesity.”

They add: “We further speculate that these improvements with regard to weight, glycemic control, blood pressure, and dyslipidemia in adolescents may mitigate the progression of adverse anatomical and physiological cardiovascular changes — changes that may be less reversible after the accumulation of more pound-years later in life.”

By Eleanor McDermid, Senior medwireNews Reporter

N Engl J Med 2015; Advance online publication

medwireNews is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2015

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