L9 HD Flashcards
two main categories of movement disorder
hypokinetic and hyperkinetic
what does a hypokinetic movement disorder entail
reduced movement
examples of hypokinetic movement disorders
- Idiopathic Parkinson’s disease
- Progressive Supranuclear Palsy (PSP)
- Multiple System Atrophy (MSA)
- Vascular Parkinsonism
- Drug-induced Parkinsonism
what does a hyperkinetic movement disorder entail
increased movement
examples of hyperkinetic movement disorders
- Tremor
- Chorea (e.g., Huntington’s Disease)
- Tics
- Hemiballismus
- Myoclonus
what was an early name for HD and where did it come from
“Chorea” (Greek for “dance”)—describes the characteristic twisting, writhing, and uncontrollable movements.
what is Huntington’s Disease
an inherited neurodegenerative movemment disorder characterised by chorea
what type of genetic disorder is HD
Autosomal dominant trinucleotide repeat disorder
where is the genetic mutation that causes HD
Chromosome 4
what is the prevalence of HD
5-8 per 100,000
what does autosomal dominant inheritance mean
- Each child of an affected parent has a 50% chance of inheriting the HD gene.
- If a person does not inherit the gene, they will not develop the disease and cannot pass it on.
- If a person does inherit the gene, they will eventually develop the disease.
- One child inheriting the gene does not affect the chances of others inheriting it.
how is HD diagnosed
- Clinical and family history
- Genetic testing
- MRI scan → Shows atrophy of caudate nuclei
typical age of onset for HD
30-55 years
what is the westphal variant of HD
a variant in which onset occurs before age 21
what percentage of HD cases does the westphal variant account for
5%
what does a younger onset of the disease indicate
that the disease may progress more rapidly
what is a common cause of death in people with HD
aspiration pneumonia
what is the survival time for people with HD
15-20 years post-diagnosis (some cases up to 30-40 years)
three types of symtoms which occur in HD
- movement
- psychiatric
- cognitive
movement symptoms in HD
- Chorea → Rapid, involuntary, non-repetitive movements
- Eye movement disorders
psychiatric symptoms in HD
- Depression, agitation, anxiety
- Increased suicide risk
cognitive symptoms present in HD
- dementia
- dysexecutive syndrome
can HD present with parkinsonism features
yes
what do the movement features in HD look like
- Choreiform, irregular, random, and variable movements.
- May appear semi-purposeful.
- Any part of the body may be affected.
- Interruption of voluntary movement by chorea.
mid-stage progression of movement symptoms
Chorea and voluntary movement impairment worsen.
late-stage progression of movement symptoms
Chorea declines, replaced by rigidity and loss of voluntary movement
early stages of cognitive decline in HD
- Loss of speed and flexibility.
- Difficulties with complex tasks.
later stages of cognitive decline in HD
- Judgment, memory, and concentration impairments.
- Global cognitive decline.
depression in HD
Found in up to 63% of patients, often appearing before neurological symptoms.
what percentage of HD cases present with mania
2-12%
other psychiatric symptoms in HD
- Irritability, anxiety, agitation, impulsivity, apathy.
- Social withdrawal, obsessiveness.
- Higher suicide rates compared to other neurological disorders.
comment on HD-related psychosis
more resistant to treatment than schizophrenia related psychosis
early signs of HD
- Social withdrawal.
- Decline in personal hygiene.
- Reduced behavioural initiation.
- Decreased spontaneous speech.
- Limited emotional expression.
does any treatment influence disease progression
no - it is all symptomatic
examples of HD management
- genetic counselling
- pharmacological treatments
- supportive care
examples of pharmacological treatments
- tetrabenazine
- antipsychotics
- antidepressants
what does tetrabenzine treat
chorea
example of an antipsychotic
olanzapine
what do antipsychotics manage
behavioural symptoms
examples of supportive care management
- Speech and Language Therapy (SALT), dieticians
- Physiotherapy
- Social services
- End-of-life decisions
clinical management of HD
- Occupational therapy
- Physiotherapy
- Communication support.
- Dysphagia management.
- Nutritional support.
- Social support.
what mangagement does OT provide
- activities of daily living
- cognition
what management does physio focus on
- mobility
- gait
- fall prevention
what rating scale is used for HD
Unified Huntington’s Disease Rating Scale (UHDRS)
what four assessment areas does the UHDRS cover
- Motor
- Cognitive
- Behavioral
- Functional
features of hyperkinetic dysarthria
- Affects all speech subsystems.
- Uncontrolled muscle contractions.
- Hypernasality, breathiness, altered speech rate.
- Articulation difficulties, harshness, monotone.
- Unplanned loudness variation, prolonged phonemes and pauses, inappropriate silences.
features of hyperkinetic dysarthria specific to HD
- Sudden forced inspiration/expiration.
- Articulatory breakdowns.
- Phonatory impairment (harsh,strained-strangled
quality, excessive loudness). - Prosody impairment (monopitch, monoloudness, reduced stress, short phrases).
managment options for dysarthria in HD
- Rate reduction techniques.
- Stress & intonation drills.
- Speaking on exhalation.
- Rhythmic breathing.
- Augmentative & Alternative Communication (AAC).
- Yes/No communication systems.
- Partner training for effective conversation.
language symptoms ocurring in HD
- Increasing difficulty understanding complex discourse and in drawing inferences.
- Latency of response.
- Word-finding difficulties.
- Reductions in numbers of words used.
- Decreasing length of utterance.
- Decreasing use of syntactical complexities.
- Increasing susceptibility to interference.
- Increasing difficulties in maintaining topic of conversation.
- Problems with perseveration.
dysphagia presentation on the hyperkinetic subgroup of HD
- Rapid lingual chorea.
- Swallow incoordination.
- Repetitive swallows.
- Prolonged laryngeal elevation.
- Inability to stop respiration.
- Frequent eructations.
dysphagia presentation in rigid-bradykinetic subgroup of HD
- Mandibular rigidity.
- Slow lingual chorea.
- Coughing on foods.
- Choking on liquids.
impacts of HD on swallow
- involuntary movement makes it difficult to cut and transfer food → person takes too much food or drink at a time; spillages
- involuntary gulps of air during swallow → aspiration or choking
- reduced throat muscle strenth → difficulty moving food through throat; multiple swallows; residue in the thriat
- involuntary lip and tongue movements → difficulty with saliva control; drooling; coughing
- involuntary chest cavity movements → regurgitation, vomiting
dysphagia treatment in HD
- Family/caregiver education.
- Feeding techniques (e.g., assisted spoon-feeding).
- Reducing anxiety and chorea during meals.
- Reducing distraction.
- Diet modification.
- Alternative feeding (e.g., PEG tube feeding).
considerations when treating someone with HD
- Caregivers may be at risk for HD.
- Familial financial burden.
- Candidacy for AAC devices.
- Consent around PEG feeding.
