Adolescents who had bariatric surgery show decreased heart disease risk

Adolescents with severe obesity who had bariatric surgery showed significant improvements in cardiovascular disease risk factors, according to the most recent "Teen Longitudinal Assessment of Bariatric Surgery" (Teen-LABS) study, published in the journal, Pediatrics. Prior to bariatric surgery, 33 percent of the study participants had three or more defined cardiovascular disease risk factors. However, three years post-surgery only 5 percent of study participants had three or more risk factors; representing significant reduction in the overall likelihood of developing cardiovascular disease later in life.

Overall, the study demonstrated bariatric surgery performed during adolescence may provide unique benefits later in life by altering the probability of the future development of adverse cardiovascular events, including the development and progression of impaired glucose metabolism, atherosclerosis, heart failure and stroke.

Teen-LABS is a multi-centre clinical study funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health (NIH) that is examining the safety and health effects of surgical weight loss procedures in the adolescent population. This on-going study is being conducted at five clinical centers in the US, including Cincinnati Children's Hospital, Nationwide Children's Hospital, Texas Children's Hospital, the University of Alabama at Birmingham, and the University of Pittsburgh Medical Center. The study's Chair, Dr Thomas H Inge is located at Children's Hospital Colorado, Denver, CO.

"This is the first large-scale analysis of predictors of change in cardiovascular disease risk factors among adolescents following bariatric surgery," said Dr Marc P Michalsky, surgical director of the Center for Healthy Weight and Nutrition at Nationwide Children's, is the lead author of the latest Teen-LABS publication, also a professor of Clinical Surgery and Pediatrics at The Ohio State University College of Medicine." The study demonstrated early improvement and reduction of cardio-metabolic risk factors, offering compelling support for bariatric surgery in adolescents."

In the paper, ‘Impact of Severe Obesity on Cardiovascular Risk Factors in Youth’, the authors compared cardiovascular risk factor clustering (CVRFC) in severely obese youth with those with lower degrees of obesity. They divided adolescent bariatricnto the degrees of obesity (class I, II, and III) and added a “class IV” category corresponding to >160% of the 95th centile of BMI for age and sex. In a cross-sectional analysis, they investigated the presence of CVRFC in 2,244 participants; in 621 who were followed longitudinally, they investigated the determinants of endpoint CVRFC.

Outcomes

Class IV obesity was associated with increased risk for CVRFC compared with overweight (p<0.001) at a similar magnitude to class III obesity (p<0.001). Male children were at greater risk for presence of CVRFC (p=0.03) compared with female children. Adiponectin (p<0.001) and leptin levels (p=0.008) were protective, independent of degree of obesity.

Baseline class IV obesity was associated with increased risk compared with overweight of having CVRFC at follow-up (p=0.001), to a similar extent as class III obesity (p=0.001). Changes in the degree of obesity were significant predictors of CVRFC on follow-up (p<0.01 per percent BMI change).

Three years post-surgery, the study showed a reduction in cardiovascular disease risk factors is associated not only with weight loss, but also with age at the time of surgery, pre-operative body BMI, sex and race. Specifically, increased weight loss, female sex and younger age at time of surgery serve to predict a higher probability of risk factor resolution. Younger participants were more likely to resolve dyslipidaemia compared to older patients, while females were more likely than males to demonstrate improvements in elevated blood pressure.

"Although relationships between change in cardiovascular disease risk factors and postoperative weight reduction were not unexpected, we learned younger patients at time of surgery were more likely to experience dyslipidaemia remission and normalization of high sensitivity C-reactive protein (a marker of inflammation), suggesting there may be advantages to undergoing bariatric surgery earlier, even among adolescents," said added Michalsky. “The results of the current study from Teen-LABS gain further significance when considering newly published data by investigators at Yale University which highlights the long-term impact of significantly elevated cardiovascular disease risk factors observed among a large sample of severely obese youth (Class III and Class IV Obesity) compared to less obese study participants.”