March 25, 2014
By David Martin
A pediatric psychologist at the University of Kansas School of Medicine is working to improve treatments for children who refuse to eat by mouth and rely on feeding tubes for nutrition.
Ann Davis, Ph.D., M.P.H., professor of pediatrics, is leading a multistate study of an outpatient protocol for helping children make the transition to eating orally. Children between the ages of 9 months and 8 years are eligible to participate in the study. Davis is looking for children who have received at least half of their food intake by tube for 3 months or longer.
Thirty percent of children experience feeding difficulties, Davis says. "It's one of the top reasons people go to their pediatrician," she says.
In some instances, the problems can be traced to a condition present at birth. Babies with Down syndrome, for example, may have trouble sucking and swallowing. In other instances, feeding problems stem from medical treatments the child has undergone. Infants with long neonatal intensive care hospitalizations may come to associate eating with pain or discomfort. Davis calls these negative associations "painful learning memories."
She adds: "They have had so many invasive procedures – usually because of a NICU stay – that they stop eating by mouth and don't like anyone messing with their face."
A range of medical conditions can require a child to need tube feeding. Davis, the director of the Center for Children's Healthy Lifestyles and Nutrition, says a significant number of children who are medically complicated will require supplemental feeding at some point in their treatment.
"There are all kinds of reasons these kids get a feeding tube," she says. "What we specialize in is getting them off their feeding tubes."
Davis has developed a protocol for helping children make the transition from tube to oral feeding. The protocol includes behavioral therapy (teaching children and parents positive mealtime behavior) and occupational therapy (children work to overcome sensory sensitivities and develop oral motor strength, tongue movement and a safe swallow).
The study Davis is leading is trying to determine if medication should be a part of effective treatment.
Her study is a randomized, controlled trial of amitriptyline, a drug originally developed as an antidepressant. In low doses, antidepressants can relieve pain. Davis says it has become more common for doctors to prescribe pain management doses of amitriptyline and related drugs to NICU babies who are having trouble eating.
For Davis, the goal is to improve current protocols so that fewer children who are tube-fed have to be admitted to inpatient feeding therapy programs, which are costly, disruptive and not widely available.
"What we try to do is get them over this hump that they have where they learn to enjoy eating and then the natural pleasures of eating can kick in," she says. "We all love to eat. You just have to get them over that point to where the natural reinforcements of eating take place."
Leah Southard, age 4, made it over the hump.
Before enrolling in Davis' study, Leah received nutrition through a feeding tube inserted through a small incision in her abdomen. The tube connected to a packet of formula she carried in a ladybug-themed backpack.
"It's been her way of life," Wendy Southard, Leah's mother, said.
Leah's medical issues developed a few months after birth. She was 10 weeks old when she was admitted to Children's Mercy Hospital with gastrointestinal problems. The stay lasted 11 months. The current diagnosis is Crohn's disease, which causes inflammation of the lining of the digestive tract.
When Leah was well enough to leave the hospital, she was not able to discard the feeding tubes that had kept her alive during her stay. The ability to eat by mouth simply did not develop in the course of her treatment, which included intravenous feeding and naso-gastric tubes. She was eventually fitted with "G-tube" tube that pumped food into her stomach 20 hours a day.
Leah did not let her G-tube get in the way. "I really think she assumed all kids have this and evolve into not having it," her mother said. At Halloween, she collected candy. She opened wrappers and put the candy in her mouth but did not chew or swallow.
Southard and her husband, Andy, enrolled Leah in Davis' study last fall. She received the behavioral and occupational therapy designed to train children to eat orally. Then, at 10 weeks, she began the transition from the G-tube to eating by mouth.
The treatment was a success. Today, she enjoys grilled cheese sandwiches, quesadillas, cake and strawberry milk.
Did amitriptyline help Leah? The study is double blinded, so neither Davis nor the Southard family knows if Leah received the drug or a placebo in the course of her treatment. That information will be not become available until after the study is completed later this year.
The study will help clarify if amitriptyline is a worthwhile component of existing treatments or a barrier that can be removed. Davis says some parents are uncomfortable with the idea of a toddler taking amitriptyline.
"A lot of parents will go home and do a Google search and say, ‘Why are you putting my kid on an anti-depressant when they're 9 months old and they have feeding problems?'" she says. "If it turns out we don't need the amitriptyline, it makes our lives a lot easier in terms of figuring out how we can deliver this treatment package to kids."
If the study shows amitriptyline to be ineffective, Davis says she would like to design a study that tests some other aspect of the feeding tube transition protocol.
Davis manages the Kansas City patients in the trial with Kelsey Dean, a registered dietician, and Osama Almadhoun, M.D., a pediatric gastroenterologist and associate professor of pediatrics at KU School of Medicine. Jose Cocjin, M.D., a pediatric gastroenterologist at Children's Mercy, is a consultant on the study.
Paul Hyman, M.D., chief of gastroenterology at Children's Hospital of New Orleans, and Hayat Mousa, M.D., a pediatric gastroenterologist at Nationwide Children's Hospital in Columbus, Ohio, are leading similar trials at their facilities.
Families interested in learning more about the study may find more information at the Pioneers Recruitment Registry.