The findings provide clear evidence that some form of brain disorder afflicts a sizeable portion of the elderly population, and offer significant material for further medical studies that could eventually lead to better methods for treating the disease.

In the study, 40,000 men and women aged 60 and over were voluntarily tested on their brain ability, not unlike an IQ test for children, said Dr Sirintorn Chansirikarnchana, the president of the Alzheimer's Disease and Related Disorders Association of Thailand.

The results of the test showed that the incidence of dementia in the Thai population is about 10 per cent, which is close to the rate in the West, which is between 5 and 10 per cent, she said.

Using a standard dementia test translated into Thai, the study tested several areas of the volunteers' memories, such as their ability to recall both what they had just learnt and older memories. It also tested their general intelligence.

In addition to providing concrete evidence of dementia in Thai people, the findings will also allow Thai scientists and doctors to learn more about the disease in terms of both treating it and preventing it, said Dr Chartri Bancheun, the director-general of the Department of Medical Services.

In a subset analysis, the researchers are using what they learnt from the first study to design a new test capable of detecting dementia at a very early stage. The standard test did not identify exactly what kind of dementia a person had, Sirintorn said.

The sooner a potential case of dementia is detected, the better the chances are that it can be treated. The available treatments will only slow down the progress of the disease, not stop it, Sirintorn said.

There are about six million people over the age of 60 in Thailand, which, according to the results of the recent survey, could mean that 600,000 have some form of dementia, Chatri said.

He said that 16 per cent of the people potentially afflicted with some form of dementia would have Alzheimer's disease, 17 per cent would have vascular dementia and the rest would come from other factors, including alcoholism, brain injuries or brain tumours.

"Despite being a degenerative disease, half of the forms of dementia are preventable," he said, adding that high blood pressure and cholesterol and alcoholism were factors that cause the preventable forms of dementia.

Dementia costs about Bt300,000 per patient per year, not to mention the disease's impact on the quality of life of both the patients and their caretakers and the loss of productivity.

"Stop drinking alcohol and smoking. Maintaining a good diet and exercising are simple ways to reduce the burden that comes with dementia," Chatri said.

"Having taken care of a cancer patient in the last stages, I can say that that did not compare to the hardship of taking care of an Alzheimer's patient," said Nuansri Anantrakul, whose older sister had Alzheimer's.

"Taking care of her forced me and another relative to sacrifice everything," she said. "It's an around-the-clock task because the patient could not be out of our sight even for a minute."

Arthit Khwankhom

The Nation