Never Full: The Curse of Prader-Willi

Feb. 6, 2008— -- In her heart, Lisa Davis knew something was wrong with her child.

A mother of four, she was no stranger to the challenges of childcare. But when her daughter Haley was 18 months old, she says, her behavior stood out as strange. And it seemed to revolve around an obsession with food.

"She was digging through the trash and eating everything, even raw meat," Davis recalls. "If we had had yogurt that day, she would lick the empty cup. She was eating butter. Anything she could find."

For more than three years, Davis searched for a medical explanation.

"The doctors kept telling me that she would outgrow it," she says. "But I knew in my heart that it was something more."

Last October, Davis's intuition turned out to be correct. A genetic test revealed that Haley, now 5, possesses a rare condition known as Prader-Willi syndrome. Among the hallmarks of the gene-linked disorder are small stature, behavioral and learning disabilities, and a ravenous appetite that can never be sated.

The Davis kitchen is now in a state of permanent lockdown. Every space in which food is stored, from the fridge to the kitchen cabinets, is under lock and key.

Still, Haley has occasionally found the keys.

"Every age is different as far as what you go through," Davis says. "As she got older, it became more of a manipulative thing. If she asked for food and I told her no, she would ask my husband; she would go to him and tell him that I told her yes."

+"Everything around food is a big deal," she adds. "You need it to survive. But to have it be something that could kill your child...."

Unlocking the Secrets of Prader-Willi

In the world of genetic disorders, Prader-Willi is a relative newcomer. The syndrome was first identified in 1956, though doctors at the time had little clue as to how it arose.

Decades later, in 1981, Dr. David Ledbetter, then a grad student at the University of Texas at Austin and now the director of the Division of Medical Genetics at Emory University's School of Medicine, was working with colleagues from Massachusetts General Hospital and Harvard. They discovered that many people with the syndrome were missing the same small stretch of genes on chromosome 15.

Dr. Merlin Butler, chief of medical genetics and molecular medicine at Children's Mercy Hospitals and a professor of pediatrics at the University of Missouri-Kansas City School of Medicine, says one theory behind the insatiable hunger may represent an adaptive measure gone haywire.

"From the clinical side, we know we all carry genes — the so-called thrift genes — which are there to help us try to store energy when availability becomes scarce," Butler explains, adding that these genes could be a throwback to a time when humans would have to be able to store and conserve energy in order to survive trying times.

"Now, during a time of excess, these genes are still doing their thing and making us obese," he says.

The condition is quite rare, Butler notes, as it affects only about one out of every 15,000 or 20,000 children. But this relative rarity may be the reason why so many children like Haley are only identified as having Prader-Willi years after signs of the condition emerge.

Butler says that often those in the medical community will misinterpret or misdiagnose the early signs of Prader-Willi. Often, he notes, the lack of muscle tone and poor sucking reflex of these babies in early life — telltale signs of the condition — are thought to be due to a brain or spinal condition. Consequently, the true condition remains obscured for years.

But it's getting better. "In the 80s, the average diagnosis was at about 10 years old," he says. "Now, diagnosis most often takes place at 10 months or earlier."

New Hope for Prader-Willi Parents

Craig Polhemus is executive director of the Prader-Willi Syndrome Association, USA. The Sarasota, Fla.-based organization was organized in 1975 to educate families on and promote awareness of Prader-Willi and other associated disorders that involve similar behaviors.

"We have to get every parent with a Prader-Willi child to understand that preventing access to food is a life-and-death issue," he says, adding that awareness and counseling has already led to an improved quality of life for individuals and families dealing with the condition.

But despite the advancements, doctors have as yet been unable to devise any treatment to take away the ravenous hunger associated with the syndrome.

People with Prader-Willi "have to be supervised 24 hours a day, every day, for their entire life," Polhemus says.

Janalee Heinemann, Director of Research and Medical Affairs for the association, has a firsthand familiarity with these challenges. Her 34-year-old stepson has Prader-Willi, and she has been key to managing his condition since he was seven.

"The reality is, obesity kills," she says. "And with kids that gain weight that quickly, it can kill young."

To manage the condition, she says setting up a routine becomes crucial so that the child knows exactly when to expect food, as well as how much food and what kind of food will be available.

"It's tough love, it's hard," she notes. "In this society, so often we show love with food. So it's the one syndrome where you can love your child to death — literally love them to death."

And she says that the challenges associated with the syndrome change as children reach adolescent and teenage years.

"The older they get, sometimes the harder it gets," she says. "They want more freedom, but these kids require so many controls that they can't have this freedom.

"My son, he can't even take a walk by himself, because he might take a walk to McDonald's, or he might walk over to the neighbors' and talk them into giving him some food," she adds.

But though the appetites of those with Prader-Willi may never disappear, Polhemus says treatment with human growth hormone, or HGH, has represented a huge step in the management of the condition.

The treatment helps Prader-Willi children gain height and muscle tone, a recipe for an increased ability for these individuals to burn excess calories. So while the hormone does not help contain appetite, it does give the children and their parents a greater caloric margin of error.

Combined with medications to control depression and impulsive behaviors, the children have a chance for happiness.

"Today, he's tall, slim and happy," Heinemann says of her stepson. She notes that HGH has allowed him to gain height, while a strict control of his access to food and psychotropic medications have helped him control his weight and mood. The outcome, she adds, does not always have to be "dismal."

And Butler says the hope for new drug treatments remains. "Potentially down the road there may be other medicines that can at least help the appetite. One would hope that through the anti-obesity drugs there might eventually be drugs to help control the appetite of those with Prader-Willi."

Treatment, he adds, has already come a long way. In the early '80s, "you wouldn't see kids who had been diagnosed with the condition. You would see adolescents or adults, many of them in wheelchairs because they were so morbidly obese. Their quality of life was really quite poor.

"The past 10 years have seen a significant difference in quality of life," he says. "Nowadays it is difficult to find a Prader-Willi person who looks like a Prader-Willi person.... [I]t really is amazing."

The Power of Knowledge

But for the time being, the best weapons against the dangers of Prader-Willi are awareness and education.

"For the new generation, if we can get to the parents when the kids are young and teach them tough love and get HGH to these kids, then we can make a big difference," Heinemann says.

"Even though the kids are sweet and loving most of the time, they can get upset," she adds. "Once you know what it is, you realize that it's not the child's fault. They can't help it."

Davis, for one, says she remains optimistic in the face of the challenges Prader-Willi presents.

"We're having a hard time with school because the teachers don't know much about it," Davis says, adding that tantrums are still common and her daughter's food-seeking impulses will likely always present a threat.

But she says her daughter's positive diagnosis represents an important first step in dealing with her condition.

"All it was was a label," she says. "It did not change anything with Haley, but it did help me understand why she was going through what she was going through."