A stroke is devastating, especially when it seriously affects physical functions, speech and mobility.
Sometimes, what may be less obvious but no less devastating is the loss of cognitive function or thinking ability that hits some 55 per cent of stroke survivors. This ranges from mild cognitive decline to dementia.
Most patients will have a condition called vascular cognitive impairment, no dementia (Vcind) and a study is currently under way to test the use of traditional Chinese medicine (TCM) on Vcind.
It is hoped that this form of treatment can cut their risk of developing further cognitive impairment that is severe enough to warrant a diagnosis of dementia.
Associate Professor Christopher Chen, the director of the Memory, Ageing and Cognition Centre at the National University Health System and principal investigator of the study, said a quarter of those with moderate Vcind go on to have dementia in five years. On the other hand, those with no or mild cognitive impairment face a risk of less than 5 per cent.
Prof Chen said Vcind is an under-recognised problem, but has serious consequences as another local study showed that it increases a person's chance of dependency by 3.8 times, risk of death by 3.3 times and recurrent vascular events (heart attack or stroke) by 1.7 times, compared with a patient with no Vcind.
With no specific treatment for Vcind, doctors can focus only on preventing more strokes by controlling conditions such as high blood pressure, diabetes and high cholesterol, all of which affect the health of the blood vessels.
A patient may also be able to build his brain reserve - the ability to tolerate age-disease-related changes in the brain - by adopting a healthy lifestyle of regular exercise and social activities, said Prof Chen, who is also the senior visiting consultant at the National University Hospital's department of psychological medicine.
But if Western medicine has no drug which can improve cognitive impairment, what about natural herbs used in TCM?
The study aims to get 100 patients who have had Vcind within 12 months of an ischaemic stroke or transient ischaemic attack. They will be randomly assigned to either the TCM treatment or a placebo for 24 weeks.