Prader-Willi syndrome is a genetic condition that occurs in about 1 in every 12,000-15,000 people. Signs and symptoms that may occur among individuals with Prader-Willi syndrome include:
- Hypotonia (low muscle tone)
- Feeding difficulties in infancy
- Excessive eating in childhood
- Developmental and cognitive delays, usually in the mild-moderate range
- Characteristic behaviors, including skin picking, temper tantrums, sleep problems, and obsessive-compulsive behaviors
- Hormone differences, including hypothyroidism and hypogonadism
It is important to remember that each person is unique and that not all individuals with Prader-Willi syndrome (PWS) have all of the symptoms listed above. There is a wide range of variability for most symptoms.
The hallmark of Prader-Willi syndrome is excessive eating. People with PWS are unable to recognize when they are full. People with Prader-Willi syndrome also have less lean muscle mass than the average person and therefore burn fewer calories. This combination of features contributes to obesity in many adults with Prader-Willi syndrome.
Hypotonia is the major feature of Prader-Willi syndrome in infancy, and may be significant enough to require tube feeding. As children with PWS get older, their muscle tone improves and they are able to eat on their own. The intense interest in food usually begins between 1 to 6 years old. Unfortunately, there is no good treatment to suppress appetite. Most people require an extremely low calorie diet all their lives and must have their environment designed to limit their access to food. If people with Prader-Willi syndrome maintain good weight control the outlook for their long-term health is good. People with PWS who do not control their weight are at risk for complications related to obesity such as type II diabetes.
Although there is no cure for Prader-Willi syndrome, there are support services and medical recommendations that can be offered to families to help their child with Prader-Willi syndrome reach their fullest potential.