The Generative Brain

How prion disease progresses

More detail

Prion disease usually starts with small changes in memory, balance, vision or mood, and these get worse over weeks and months. Sporadic CJD typically runs over a few months, while the inherited forms often run longer, nearer two years. Much of the care is about comfort, and a palliative team can help from early on.

How changes in the brain can show up
  1. 1Front of the brainThinking, planning, personality and mood
  2. 2Side of the brainMemory and finding words
  3. 3Deep centre, the thalamusSleep and body rhythms
  4. 4Back of the brainSight
  5. 5CerebellumBalance and coordination

A simplified picture. Prion disease can affect many areas, and which come first differs by person and by type of disease.

How the focus of care often changes
  1. EarlyDiagnosis, wishes, support and planning.
  2. MiddleHelp at home, safety, eating and communication.
  3. LaterComfort, nursing care and family support.
  4. AfterGrief support, and research if wished.

Every person is different, and changes can come quickly.

Reading about progression is one of the hardest things a family does, and it is also one of the most useful, because knowing roughly what comes next makes it possible to arrange help before it is needed. Take it in pieces if you need to. A specialist nurse or a palliative care team will go through all of it with you, as many times as you want.

What happens at the start?

The first changes are often small and easy to attribute to something else: difficulty walking, slurred speech, numbness or pins and needles, dizziness, double vision, memory lapses or hallucinations. In variant CJD the first changes are usually psychological, with low mood, withdrawal, anxiety or irritability, and neurological symptoms following a few months later.

These early symptoms worsen over the space of a few months in sporadic CJD. Symptoms covers them one by one.

How fast does it usually go?

That depends on which form it is, and it varies between people with the same form.

Sporadic CJD usually runs over about 4 to 5 months from the first symptoms. The inherited forms generally run more slowly, often around 2 years. Variant CJD has averaged about 13 to 14 months. Gerstmann-Straussler-Scheinker disease can run for several years.

These are averages from groups of patients, and nobody can tell you the course for one person. Clinicians are advised to talk about the usual pattern and the uncertainty together, rather than giving a single figure.

What happens in the middle stage?

Movement and coordination become harder, with unsteadiness and muscle twitches or jerks. Memory loss, confusion and difficulty concentrating increase. Agitation, distress or suspicion can appear. Vision can be affected, swallowing becomes difficult and speech is gradually lost, as is control of the bladder and bowel.

Most of these can be treated or eased. There are recommended approaches for the muscle jerking, for pain, for poor sleep and for distress, and published guidance now sets out which medicines are used at which stage. Agitation is understood as a sign of an unmet need, which is worth knowing, because the first question is usually whether something hurts or something in the room is frightening rather than which drug to give.

This is also the point at which practical help makes the most difference: equipment at home, help with washing and feeding, speech and language therapy for swallowing, and respite so the people caring can rest. What to expect goes through the arrangements.

What are the last weeks like?

People become bedbound, often unaware of their surroundings, and need care around the clock. Speech is usually gone by then, and the advanced stage of prion disease is sometimes described in medical notes as akinetic mutism, meaning the person neither moves nor speaks. How long this stage lasts varies.

Death usually follows from an infection such as pneumonia, or from breathing failure. With good end of life care it is generally peaceful, and that is the part families most often say they wish someone had told them earlier.

What can be arranged, and when?

Earlier than most people think. Published recommendations say planning should start as soon as possible, ideally at diagnosis, because the illness can move quickly and because decisions become harder once someone is no longer able to express their wishes.

A palliative care team can be involved from early on, and in prion disease specialists say they are often brought in later than they should be. Carers need support in their own right, including information, practical help, training in care tasks, respite and help with money. Palliative and hospice care explains what those teams do, and support groups lists people who talk with families every day.

One reassurance is worth stating plainly, because it worries households unnecessarily. There is no evidence that CJD passes from person to person through ordinary social or clinical contact, and normal care at home needs no special precautions. Myths and facts covers the other common worries.

Where next?

How prion disease progresses: more detail is the clinical version of this page, with the staging and the symptom management in full. Rapidly progressive dementia and CJD covers the diagnostic stage, and prion diseases the individual conditions.

Nothing here describes a particular person. Questions about what is happening now, and what to expect next, belong with the treating neurologist and the palliative care or specialist nursing team.

Sources for this page