7-29-16 Huntington Disease Dementia

© 2016           

By Keith S. Wexler, MBA, Maternal Fetal Medicine, Prenatal Diagnosis and Biotech Consultant, GENASSIST, Inc.

Paul Wexler, M.D., F.A.C.O.G., Medical Director, GENASSIST, Inc.

Clinical Professor, Department of OB/GYN, University of Colorado Health Sciences Center Clinical Professor, Division of Genetics/Dept. of Pediatrics, Univ. of Colorado/The Children’s Hospital

Definitions:

Dementia: A chronic or persistent disorder of the mental processes caused by brain disease or injury or marked by memory disorder, personality change or impaired reasoning.

Huntington’s Disease: Is a progressive disease which results in shrinkage of caudate nucleus and putamen and ventriculomegaly. Huntington Disease is usually inherited in an autosomal dominant manner. 1-3% of cases are sporadic.

At least 100 interacting proteins have been described with Huntington’s.

Incidence:

  • 1 in 10,000 to 1 in 30,000
  • Usually affects individuals at 30 to 50 years of age
  • 16% of cases occur before 20 years of age (Juvenile Huntington’s Disease) – Juvenile Disease is usually more progressive and seizures may occur in 1/3 to ½ of these children.

http://hdsa.org/

Huntington Disease Gene (HTT) on the short arm of chromosome #4 (4p 16.3 ) provide instructions for making the protein Huntingtin.

CAG Repeat in the gene are usually increased in the disease:

  • Normal CAG repeats </= 28 in the HTT gene codes for Huntington protein – protects against cell death (apoptosis) primarily in brain)
  • Increased risk to next generation – 29 to 34 repeats – unaffected parent
  • Increased Risk to next generation – 35-39 repeats – some increased risk to patient
  • Greater than or equal to 40 repeats – individual will get Huntington’s Disease
  • Juvenile Huntington’s Disease children often have more than 60 repeats

Symptoms of Huntington’s Disease Dementia:

  • Movement disorders
  • Cognitive and reasoning problems
  • Personality changes
  • Psychiatric disorders

As the disease passes from one generation to the next symptoms may be seen earlier (Anticipation)

https://www.linkedin.com/pulse/genetic-anticipation-keith-s-wexler?trk=mp-author-card

Medications:

  • Tetrabenazine (Xenazine) for movement disorder specifically chorea
  • Haldol
  • Chlorpromazine
  • Risperdal
  • Seroquel
  • Keppra
  • Klonopin
  • Amantadine
  • Zyprexa
  • Antidepressants

*Any of the medications can worsen symptoms and can cause dependence, abuse, and drowsiness.

Treatment:

  • Speech Therapy
  • Occupation Therapy
  • Physical Therapy
  • Psychotherapy