Still hungry for a cure.
WHAT is Prader-Willi syndrome (PWS)?
PWS is a complex genetic disorder affecting appetite, growth, metabolism, cognitive function and behavior. It is typically characterized by low muscle tone, short stature, incomplete sexual development, cognitive disabilities, problem behaviors, and the hallmark characteristics—involuntary and uncontrollable chronic feelings of hunger and a slowed metabolism that can lead to excessive eating and life-threatening obesity. Those who have PWS need intervention and strict external controls, including padlocking access to food, to maintain normal weight and to help save their lives. PWS is a lifelong condition in which there is no know cure….YET!
WHO has Prader-Willi syndrome?
It is estimated that one in 12,000 to 15,000 people has PWS. Prader-Willi syndrome does not discriminate; anyone can be born with PWS, it affects both males and females of all ethnic backgrounds. Although considered a “rare” disorder, PWS is one of the most common conditions seen in genetics clinics and is the most common genetic cause of obesity that has been identified.
WHY does Prader-Willi syndrome occur?
Most cases of PWS are attributed to a spontaneous genetic error that occurs at or near the time of conception for unknown reasons. In a very small percentage of cases (2% or less), a genetic mutation that does not affect the parent is passed on to the child, and in these families more than one child may be affected. A PWS-like disorder can also be acquired after birth if the hypothalamus portion of the brain is damaged through injury or surgery.
WHAT is known about the genetic abnormality?
Basically, the occurrence of PWS is due to lack of several genes on one of an individual’s two chromosome 15s—the one normally contributed by the father. In the majority of cases, there is a deletion—the critical genes are somehow lost from the chromosome. In most of the remaining cases, the entire chromosome from the father is missing and there are instead two chromosome 15s from the mother (uniparental disomy). The critical paternal genes lacking in people with PWS have a role in the regulation of appetite. This is an area of active research in a number of laboratories around the world, since understanding this defect may be very helpful not only to those with PWS but to understanding obesity in otherwise normal people.
WHAT are the appetite and obesity problems associated with PWS?
People with PWS have a flaw in the hypothalamus part of their brain, which normally registers feelings of hunger and satiety. While the problem is not yet fully understood, it is apparent that people with this flaw never feel full; they have a continuous urge to eat that they cannot learn to control. To compound this problem, people with PWS need less food than their peers without the syndrome because their bodies have less muscle and tend to burn fewer calories.
Newborns with PWS often cannot get enough nourishment because low muscle tone impairs their sucking ability. Many require special feeding techniques or tube feeding for several months after birth until muscle control improves. Sometimes in the following years, usually before school age, children with PWS develop an intense interest in food and can quickly gain weight if calories are not restricted.
Unfortunately, appetite suppressants haven’t worked consistently for people with PWS. Instead, an extremely low-calorie diet is required, as well as an environment designed to limit access to food. For example, many families have to lock their kitchen cabinets and refrigerators.
As adults, some individuals find controlling their weight is more easily managed in a PWS group home setting, as food access can be monitored without interfering with those who don’t require such restriction.
WHAT kinds of behavioral issue do people with PWS have?
In addition to their involuntary focus on food, people with PWS tend to have obsessive/compulsive behaviors that are not related to food. Some are repetitive thoughts and verbalizations, collecting and hoarding of possessions, picking at skin irritations, and a strong need for routine and predictability. Frustration or changes in plans can easily set off a loss of emotional control in someone with PWS, ranging from tears and temper tantrums to physical aggression. While psychotropic medications can help some individuals, the essential strategies for minimizing difficult behaviors in PWS are careful structuring of the person’s behavior management and supports.
WHO to contact for more information:
Contact the Prader-Willi Syndrome Association at (800) 926-4797 toll-free in the US or (941) 312-0400 or visit their website at www.pwsausa.org. PWSA is the only national membership organization that is dedicated to improving the lives of all persons afflicted with Prader-Willi syndrome and supporting them at every stage of life through research, education, support and advocacy. Headquartered in Sarasota, FL, it was formed in 1975 to provide a vehicle of communication for parents, professionals, and other interested citizens. Hospitals, physicians, and parents from all over the world consult with PWSA about medical emergencies and questions daily.
*Source: Prader-Willi Syndrome Association
6805 Porto Fino Circle
Fort Myers, Florida 33912