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What is Dutchtype CAA?

Dutchtype CAA

Dutchtype Cerebral Amyloid Agiopathy is a hereditary form of cerebral haemorrhaging. It is also known as HCHWA-D (Hereditary Cerebral Haemorrhage with Amyloidosis  - Dutch type) or the Katwijk disease. The disease is caused by a gene mutation that causes the accumulation of amyloid beta in the blood vessels of the brain, damaging them and causing them to rupture. 

The development of the disease

The first outward sign of the disease is the initial ‘stroke’- which usually occurs between the ages of 45 and 65, with an average age of 55. Strokes have been recorded as early as age 39 and as late as 76. Reoccurring strokes, varying in frequency and severity occur. Sometimes people already notice cognitive decline before having a stroke. For unknown reasons, progression of Dutchtype CAA is different for each individual patient:

  • About one third of HCHWA-D patients die as a result of the effects of their first stroke.
  • Patients who survive the initial haemorrhage, are often affected by recurring strokes. On average, 3 recurring strokes with a maximum of 10 recorded strokes.
  • These haemorrhages can result in severe brain damage.
  • The average life expectancy of a patient with DCAA after the initial stroke is approximately 10 years (ranging up to 20 years).
  • DCAA is associated with dementia (vascular dementia).
  • The number of haemorrhages and the age at which they initially occur can vary greatly- even within one family. 

Treatment for Dutchtype CAA

Unfortunately DCAA can not be treated. Following a healthy lifestyle is recommendable but a connection between, for example, high blood pressure, food, smoking or drinking and DCAA has not been established by research.

How many people have DCAA?

We know of dozens of families in the Netherlands that carry the gene, but do not know how many exactly. Most of them live in Katwijk and Scheveningen, with some living in other parts of the Netherlands. All of them descent from Katwijk. There is a large family in Australia as well, who are all related to Jan Plug, who moved to Perth (and Albany) after World War II. We do know of other families in Australia, South Africa and Schotland who carry the gene. It is hard to get the right diagnose, because the disease is so rare and not many neurologists know of it.