SINGAPORE - 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.
An ischaemic stroke occurs when a blood clot in the brain prevents the flow of blood, thus causing brain damage, while a transient ischaemic attack is a medical condition in which blood flow to a part of the brain stops for a brief period of time.
Those in this treatment group consume capsules which contain nine plant extracts, such as red peony root and safflower, thrice a day. This preparation has been shown in animal studies to have actions that could lead to reducing the impact of Vcind. An earlier Singapore study, also by Prof Chen, confirmed the safety of a similar TCM formula in more than 1,000 patients who were recruited within 72 hours of their strokes.
This new research is a double blind study, in which neither researcher nor subject knows who is getting the new therapy or the placebo. It will put patients through tests to assess their thinking skills, including their memory, executive function (the ability to plan, organise and pay attention to detail) and mental processing speed.
Prof Chen's team has recruited 24 patients at NUH since the study began in April last year and will recruit patients from the Singapore General Hospital from next month. All study participants are between 55 and 85 years old.
One of them is Mr Chan Ying Wai, 70, a former mechanical engineer. In February, a magnetic resonance imaging scan picked up a mini-stroke (transient ischaemic attack) which had gone undetected because he showed no symptoms.
His wife, Madam Chan Yee Wan, 65, said that in recent years, his ability to do mental sums has deteriorated and there were instances when he left the house keys hanging on the door.
Mr Chan, a hepatitis B carrier with high blood pressure and high cholesterol, is hopeful the trial will help him.Mrs Chan said: "It has never crossed our minds that he is like a guinea pig. Taking the capsules in the study is safer than taking medicine that you buy on your own."
To participate in the study, contact Ms Ng Wan Ting on 6772-6583 or 8421-0428
This article was first published on July 31, 2014. Get a copy of Mind Your Body, The Straits Times or go to straitstimes.com for more stories.