Frequently Asked Questions

What is Prader-Willi Syndrome?

PWS is a complex genetic disorder caused by a deletion in chromosome 15. The deletion has a range of physical, intellectual and behavioural effects on individuals. The most distinctive impact on older children and adults is a persistent sense of hunger and lack of satiation. This can lead to obesity, if not effectively managed.

How common is PWS?

The prevalence of PWS is estimated to be between 1:12,000 and 1:15,000 births. PWS occurs at the same rate for males and females in all races.

How is PWS diagnosed?

There are clinical criteria for a diagnosis of PWS, but chromosome analysis provides the most reliable and useful diagnosis.

What are some typical characteristics of individuals with PWS?

Age 0 to 6
- Weak muscle tone (hypotonia), infants sometimes described as being "floppy"
- Weak sucking reflex and difficulty feeding
- Developmental delay
Age 6 to adolescence
- Persistent sense of hunger and lack of satiation (hyperphagia), leading to obesity, if not managed.
- Short stature, small hands and feet
- Mild intellectual impairment and learning disabilities
Adolescence to adulthood (in addition to previous characteristics)
- Behaviour challenges, such as obsessive-compulsive disorder
- Obsession with food
- Sleep disorders/sleep apnea

What other health problems may be associated with PWS?

Lack of vomit reflex
High pain threshold
Impaired regulation of body temperature
Speech articulation defects
Skin picking
Eye abnormalities
Scoliosis and osteoporosis
If weight is not controlled, there is a higher risk of health issues related to obesity, including cardio-vascular and respiratory illnesses and diabetes.

Is there a cure for PWS?

While a "cure" is not currently available, there are many medical and behavioural interventions that can minimize the impact of the genetic condition, allowing the individual to lead a life that is normal in many respects. Early diagnosis, treatment and multi-disciplinary management all play important roles.

What medical treatment is available for individuals with PWS?

Access to specialized medical treatment begins with the primary care physician. Since PWS is relatively rare, many family physicians may be unfamiliar with this complex disorder. The Ontario PWS Association (OPWSA) provides excellent information and linkages to medical expertise in PWS.

When there is a clear diagnosis of PWS, growth hormone treatment can produce effective results. It supplements the pituitary gland, helping the individual achieve normal stature, improve muscle tone, and maintain bone density and a healthier fat to muscle ratio. An endocrinologist does the assessment and manages growth hormone treatment.

Depending on the needs of the individual, a variety of other interventions may be delivered by medical professionals, such as a developmental pediatrician, neurologist, orthopedic specialist, orthotist, optomologist, dentist, psychiatrist, or psychologist.

What non-medical interventions benefit individuals with PWS and their families?

Since PWS may include a combination of cognitive disabilities and behavioural challenges, in addition to medical issues, a wide range of services and supports may be beneficial, including:

Physiotherapy
Occupational therapy
Nutrition and dietitian consultation
Speech and Language therapy
Behaviour therapy
Physical training
Employment Consultation

What is the PWS Network?

The PWS Network was established in 2006:

to increase the availability of information and best practices about PWS for service providers in southern Ontario.
to determine training needs and develop appropriate training resources for staff working with individuals with PWS and their families

Members of the PWS Network are service providers located in Central West Region, in southern Ontario, Canada. Those who currently, or potentially, provide services to individuals with PWS are listed in the Directory. Other providers are corresponding Network members. The Network is closely associated with the Ontario PWS Association.