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Behavioral and psychiatric disorders in Prader-Willi syndrome: a population study in Japan

Rika Hiraiwa1, Yoshihiro Maegaki, Akira Oka

  • 1Division of Child Neurology, Faculty of Medicine, Tottori University, Yonago, Japan. r-hiraiwa@sw-shimasei.jp

Brain & Development
|February 23, 2007
PubMed

Insights

Prader-Willi syndrome (PWS) presents significant behavioral and psychiatric challenges that increase with age. Young adults with PWS show higher rates of these disorders compared to individuals with intellectual disability from other causes.

Area of Science:

  • Neurodevelopmental Disorders
  • Genetics
  • Psychiatry

Background:

  • Prader-Willi syndrome (PWS) is a genetic disorder causing intellectual disability and distinct physical, behavioral, and psychiatric issues.
  • Behavioral and psychiatric disorders are common in PWS, but their prevalence and age-related changes require further investigation.

Purpose of the Study:

  • To examine the prevalence of behavioral and psychiatric disorders in individuals with PWS across different age groups in Japan.
  • To compare the behavioral and psychiatric profiles of young adults with PWS to those with intellectual disability (ID) from other causes.

Main Methods:

  • Parental questionnaires were used to assess behavioral and psychiatric disorders in 165 individuals with PWS (aged 2-31 years).
  • Participants were divided into four age groups: 2-5, 6-11, 12-17, and 18-31 years.
  • A comparison was made between the PWS young adult group (18-31 years) and 42 age-, gender-, and IQ-matched individuals with ID without PWS.

Main Results:

  • Repetitive speech and stubbornness were common early symptoms in PWS.
  • Hyperphagia, food stealing, temper tantrums, lying, and emotional lability increased with age in individuals with PWS.
  • Young adults with PWS exhibited significantly higher rates of stubbornness, hyperphagia, temper tantrums, self-injurious behavior, hypersomnia, inactivity, and delusions compared to the ID control group.

Conclusions:

  • Behavioral and psychiatric disorders in PWS tend to worsen with age, particularly in young adulthood.
  • Individuals with PWS are more susceptible to a range of behavioral and psychiatric disorders than those with ID from other etiologies.
  • Obesity levels did not correlate directly with the severity of behavioral and psychiatric features in PWS.

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