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child measuring his stomach

Cognitive function does not predict weight-loss outcome for adolescents

child measuring his stomach

Though young people with intellectual disabilities or cognitive impairment have greater rates of obesity and other comorbidities that impact their health and well-being, primary care providers are often reluctant to discuss or refer these patients for weight-loss surgery due to concerns about their ability to assent to both the surgery and the ongoing diet and lifestyle changes after surgery.

However, a study in Pediatrics authored by psychologists at Children’s National Health System finds that these young people, including those with Down syndrome, have similar weight-loss trajectories to those with typical cognitive function after bariatric surgery. The study is the first to look at post-surgical outcomes for this subgroup of adolescent bariatric surgery patients.

“It’s challenging to ensure that an adolescent who is cognitively impaired understands what it means to undergo a surgical procedure like bariatric surgery, but we do find ways to ensure assent whenever possible, and make sure the patient also has a guardian capable of consent,” says Sarah Hornack, Ph.D., a clinical psychologist at Children’s National and the study’s first author. “A very important determinant of post-surgical success for any young candidate, however, is a support structure to help them with weight-loss surgery requirements. Often, we see that adolescents with lower cognitive function already have a well-established support system in place to assist them with other care needs, that can easily adapt to providing structure and follow through after weight-loss surgery, too.”

The study reviewed outcomes for 63 adolescents ranging in age from 13 to 24 years old with an average body mass index of 51.2, all of whom were part of the bariatric surgery program at Children’s National Health System. The participants were diagnosed with cognitive impairment or intellectual disability via standardized cognitive assessments as part of a preoperative psychological evaluation or through a previous diagnosis. This study adds to the body of research that is helping to create standard criteria for bariatric surgery in adolescents and teenagers.

Children’s National is one of only a few children’s hospitals with accreditation from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program of the American College of Surgeons and the American Society for Metabolic and Bariatric Surgery to offer bariatric surgery for adolescents with severe obesity. The extraordinary diversity of the patient population in Washington, D.C., including high rates of young people with obesity, allows the team to collect more comprehensive information about successful interventions across subgroups, including cognitive impairment or developmental disabilities, than nearly every other center in the United States.

“We’re happy to contribute evidence that can help families and care providers make informed health decisions for young people with intellectual disabilities or cognitive impairments. So many families are hoping to make sure that their children, despite disabilities, can be as healthy as possible in the long term,” says Eleanor Mackey, Ph.D., who is also a clinical psychologist at Children’s National and served as the study’s senior author. “Though the sample size is small, it does give credence to the idea that for many adolescents and teenagers, weight loss surgery may be a really viable option regardless of pre-existing conditions such as intellectual ability or cognitive function.”

Preemie Baby

Getting micro-preemie growth trends on track

Preemie Baby

According to Children’s research presented during the Institute for Healthcare Improvement 2018 Scientific Symposium, standardizing feeding practices – including the timing for fortifying breast milk and formula with essential elements like zinc and protein – improves growth trends for the tiniest preterm infants.

About 1 in 10 infants is born before 37 weeks gestation. These premature babies have a variety of increased health risks, including deadly infections and poor lung function.

Emerging research suggests that getting their length and weight back on track could help. According to Children’s research presented during the Institute for Healthcare Improvement 2018 Scientific Symposium, standardizing feeding practices – including the timing for fortifying breast milk and formula with essential elements like zinc and protein – improves growth trends for the tiniest preterm infants.

The quality-improvement project at Children’s National Health System targeted very low birth weight infants, who weigh less than 3.3 pounds (1,500 grams) at birth. These fragile infants are born well before their internal organs, lungs, brain or their digestive systems have fully developed and are at high risk for ongoing nutritional challenges, health conditions like necrotizing enterocolitis (NEC) and overall poor development.

The research team measured progress by tracking the micro-preemies’ mean delta weight Z-score for weight gain, which measures nutritional status.

“In this cohort, mean delta weight Z-scores improved by 43 percent, rising from -1.8 to the goal of -1.0, when we employed an array of interventions. We saw the greatest improvement, 64 percent, among preterm infants who had been born between 26 to 28 weeks gestation,” says Michelande Ridoré, MS, Children’s NICU quality-improvement program lead who presented the group’s preliminary findings. “It’s very encouraging to see improved growth trends just six months after introducing these targeted interventions and to maintain these improvements for 16 months.”

Within Children’s neonatal intensive care unit (NICU), micro-preemies live in an environment that mimics the womb, with dimmed lighting and warmed incubators covered by blankets to muffle extraneous noise. The multidisciplinary team relied on a number of interventions to improve micro-preemies’ long-term nutritional outcomes, including:

  • Reducing variations in how individual NICU health care providers approach feeding practices
  • Fortifying breast milk (and formula when breast milk was not available), which helps these extra lean newborns add muscle and strengthen bones
  • Early initiation of nutrition that passes through the intestine (enteral feeds)
  • Re-educating all members of the infants’ care teams about the importance of standardized feeding and
  • Providing a decision aid about feeding intolerance.

Dietitians were included in the daily rounds, during which the multidisciplinary team discusses each infant’s care plan at their room, and used traffic light colors to describe how micro-preemies were progressing with their nutritional goals. It’s common for these newborns to lose weight in the first few days of life.

  • Infants in the “green” zone had regained their birth weight by day 14 of life and possible interventions included adjusting how many calories and protein they consumed daily to reflect their new weight.
  • Infants in the “yellow” zone between day 15 to 18 of life remained lighter than what they weighed at birth and were trending toward lower delta Z-scores. In addition to assessing the infant’s risk factors, the team could increase calories consumed per day and add fortification, among other possible interventions.
  • Infants in the “red” zone remained below their birth weight after day 19 of life and recorded depressed delta Z-scores. These infants saw the most intensive interventions, which could include conversations with the neonatologist and R.N. to discuss strategies to reverse the infant’s failure to grow.

Future research will explore how the nutritional interventions impact newborns with NEC, a condition characterized by death of tissue in the intestine. These infants face significant challenges gaining length and weight.

Institute for Healthcare Improvement 2018 Scientific Symposium presentation

  • “Improved growth of very low birthweight infants in the neonatal intensive care unit.”

Caitlin Forsythe, MS, BSN, RNC-NIC, NICU clinical program coordinator, Neonatology, and lead author; Michelande Ridoré, MS, NICU quality-improvement program lead; Victoria Catalano Snelgrove, RDN, LD, CNSC, CLC, pediatric clinical dietitian; Rebecca Vander Veer, RD, LD, CNSC, CLC, pediatric clinical dietitian; Erin Fauer, RDN, LD, CNSC, CLC, pediatric clinical dietitian; Judith Campbell, RNC, IBCLC, NICU lactation consultant; Eresha Bluth, MHA, project administrator; Anna Penn, M.D., Ph.D., neonatologist; Lamia Soghier, M.D., MEd, Medical Unit Director, Neonatal Intensive Care Unit; and Mary Revenis, M.D., NICU medical lead on nutrition and senior author; all of Children’s National Health System.

Scientist with centrifuge

Giving fat cell messages a positive spin

Woman on a scale

Study findings offer hope to the nearly 2 billion adults who are overweight or obese worldwide that detrimental effects of carrying too much weight can recede. (Image source: Centers for Disease Control and Prevention)

Losing weight appears to reset the chemical messages that fat cells send to other parts of the body that otherwise would encourage the development of Type 2 diabetes, substantially reducing the risk of that disease, a team led by Children’s National Health System researchers report in a new study. The findings offer hope to the nearly 2 billion adults who are overweight or obese worldwide that many of the detrimental effects of carrying too much weight can recede, even on the molecular level, once they lose weight.

In 2015, Robert J. Freishtat, M.D., M.P.H., Chief of Emergency Medicine at Children’s National and Associate Professor of Pediatrics, Emergency Medicine and Integrative Systems Biology at The George Washington University School of Medicine & Health Sciences, and colleagues showed that fat cells (also known as adipocytes) from people who are obese send messages to other cells that worsen metabolic function. These messages are in the form of exosomes, nanosized blobs whose contents regulate which proteins are produced by genes. Exosomes are like “biological tweets,” Dr. Freishtat explains — short signals designed to travel long distances throughout the body.

Dr. Freishtat’s earlier research showed that the messages contained in exosomes from patients who are obese alter how the body processes insulin, setting the stage for Type 2 diabetes. However, says Dr. Freishtat, it has remained unclear since that publication whether these aberrant messages from adipocytes improve after weight loss.

“We’ve known for a long time that too much adipose tissue is bad for you, but it’s all moot if you lose the weight and it’s still bad for you,” he explains. “We wanted to know whether these negative changes are reversible. If you reduce fat, does the disease risk that goes along with excess fat also go away?”

Details of the study

To investigate this question, Dr. Freishtat and colleagues worked with six African American adults scheduled to receive gastric bypass surgery — a nearly surefire way to quickly lose a large amount of weight. The volunteers, whose average age was 38 years, started out with an average body mass index (BMI) of 51.2 kg/m2. (The Centers for Disease Control and Prevention considers a healthy BMI to range between 18.5 to 24.9.)

Two weeks before these volunteers underwent surgery, researchers collected blood samples and took a variety of measurements. The researchers then performed a repeat blood draw and measurements one year after the surgery took place, when the volunteers’ average BMI had dropped to 32.6.

Dr. Freishtat and colleagues drew out the adipocyte-derived exosomes from both sets of blood samples and analyzed their contents. The team reports in the January 2017 issue of Obesity that at least 168 microRNAs — the molecules responsible for sending specific messages — had changed before and after surgery. Further analyses showed that many of these microRNAs were involved in insulin signaling, the pathways that the body uses to regulate blood sugar. By changing these outgoing microRNAs for the better, Dr. Freishtat says, adipocytes actively were encouraging higher insulin sensitivity in other cells, warding off Type 2 diabetes.

Sure enough, each volunteer had better insulin sensitivity and other improved markers of metabolic health post-surgery, including lower branched chain amino acids and a two-fold reduction in their glutamate to glutamine ratio.

“These volunteers were essentially cured of their diabetes after surgery. The changes we saw in their surgery-responsive microRNAS correlated with the changes we saw in their metabolic health,” Dr. Freishtat says.

A glimpse into the future

Dr. Freishtat and colleagues plan to study this phenomenon in other types of weight loss, including the slower and steadier paths that most individuals take, such as improving diet and doing more exercise. The team expects to see similar changes in exosomes of patients who lose weight in non-surgical ways.

By further examining the aberrant messages in microRNAs being sent out from adipocytes, he says, researchers eventually might be able to develop treatments to reverse metabolic problems in overweight and obese patients before they lose the weight, improving their health even before the often challenging process of weight loss begins.

“Then, if you can disrupt this harmful signaling in combination with weight-loss strategies,” Dr. Freishtat says, “you’re really getting the best of both worlds.”

Eventually, he adds, tests might be available so that doctors can warn patients that their fat cells are sending out harmful messages before disease symptoms start. By giving patients an early heads up, Dr. Freishtat says, patients might be more likely to heed advice from physicians and make changes before it’s too late.

“If doctors could warn patients that their fat is telling their blood vessels to fill up with plaque and trigger a heart attack in 10 to 20 years,” he says, “patients might be more compliant with treatment regimens.”