Prader-Willi syndrome (PWS) is a rare genetic neurodevelopmental disorder caused by the lack of paternally expressed genes on the chromosome 15q11-q13. PWS affects approximately 1 in 10,000-25,000 individuals. The primary feature of PWS is hyperphagia, a chronic and life-threatening condition characterized by feelings of intense, persistent sensation of hunger accompanied by food preoccupations, and an extreme drive to seek and consume food, which can severely diminish the quality of life for individuals with PWS and their families.
Additional characteristics of PWS include behavioral problems, cognitive disabilities, low muscle tone, short stature (when not treated with growth hormone), the accumulation of excess body fat, developmental delays, and incomplete sexual development. Hyperphagia can lead to significant mortality (e.g., stomach rupture, choking, accidental death due to food seeking behavior) and longer term, co-morbidities such as diabetes, obesity, and cardiovascular disease.
Approximately 85% of people living with PWS will reach a stage characterized by hyperphagia (insatiable hunger). For some, this occurs as early as age four, and on average about age eight and then continues into adulthood. Hyperphagia occurs because of a failure of the normal appetite regulatory mechanisms in the hypothalamus, which can lead to increased appetite or food consumption, reduced satiety and a range of disruptive food related behaviors, including aggressive food seeking.
At this stage many children and adults are relentlessly seeking and thinking about food and may:
- Become angry or frustrated if denied food or asked to stop talking about food.
- Often consume any accessible food including frozen food, pet food, and even non-food items.
- Can continue to eat until the stomach ruptures.
- Steal food or money to buy food and hoard and hide food to eat later.
Individuals with PWS are at risk of suffering significant health and quality of life consequences, including morbid obesity and premature death.
C-US-PWS-00106 v1 04/2025
Spread Kind Words about PWS.
Use our educational graphics on your social media.