Most people with the disease will suffer from strokes. These most commonly first occur in the 40s to 70s. Recent data has shown that the average age of first stroke in the UK is increasing and is now 60 years of age. However, the disease can be very variable even within the same family. In some people, no problems may occur until their 60s or 70s, and we are seeing an increasing number of individuals identified with CADASIL who remain well into their 70s. The strokes are what we refer to as lacunar strokes (literally meaning a small lake or hole in the brain). Because they are small, they tend to be fairly mild and individuals often recover well. The most common type of stroke causes weakness affecting one side of the body, which is most often arm or leg weakness, or slurring of the speech. If recurrent strokes occur, this can lead to persistent disability.
Migraine is another common feature of CADASIL. This most commonly starts in the 20s, but the age of onset is variable. Usually it is what we call ‘complex’ migraine. This means that, in addition to the headache, there are aura, which are short-lived neurological symptoms, most MRI brain scan showing small strokes (indicated by arrow) in CADASIL commonly disturbance of vision, numbness down one side of the body, or speech disturbance. Sometimes aura can occur without headache. We know that migraine, while it can be distressing and painful, is not associated with any worsening of the disease or brain damage.
Individuals with CADASIL can suffer from anxiety or depression. Not surprisingly, depression is very frequent after any type of stroke and usually improves with time, although treatment may be necessary. Over time, as the disease progresses, cognitive (memory and other ‘thinking’) problems may occur. As people get older dementia may occur. Recent data showed that the average age of onset of dementia in CADASIL in the UK is 74 years.
One unusual feature is the onset of confusion and reduced consciousness over a period of hours or days, sometimes with fever and seizures; this often follows a migraine attack. This is known as encephalopathy. It recovers completely over 1 to 3 weeks and usually has no long-term effect on the course of the disease.