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Experts say a growing trend of developing tests that can predict the chances of an illness striking has the potential to save lives and medical costs. POON CHIAN HUI reports
Studies predicting when medical conditions may strike have been in the news recently.
Just last month, a study by Belgian researchers published in the medical journal Neurology said a simple spinal-fluid test can predict who is at high risk of getting Alzheimer’s disease.
Also last month, British scientists said they had developed a 15-minute brain scan that can detect autism.
Some laymen may wonder how being able to predict diseases like Alzheimer’s earlier can be helpful. After all, what’s the use of playing fortune-teller when doctors remain powerless to stop the disease from eventually cropping up?
 However, researchers here say that such research – which can be expensive – is often useful.
“Such large-scale studies involving hundreds of patients are very expensive; so why do we do it?” said Dr Liu Jianjun, the associate director of the human genetic programme and senior group leader at the Genome Institute of Singapore.
He then explained: “While researchers are unable to stop the onset of the disease, they can help doctors delay it.
“If one can delay Alzheimer’s by 10 years, for example, a lot in terms of medical costs can be saved.”
Neurologist Nagaendran Kandiah of the National Neuroscience Institute added that better predictive tests can also help nip diseases in the bud.
“In diseases like dementia, the extent of brain damage worsens over time,” he said. “Therefore, if doctors can screen for and diagnose the disease in its early stages, patients can be treated before permanent brain damage occurs.
“Otherwise, patients may seek medical help early but their efforts will be in vain if we don’t have the tools to pinpoint the ailment.”
Prediction versus intervention
Heart disease is another research hot spot where early identification can save lives.
Dr Raymond Lee, a consultant cardiologist at Novena Heart Centre, said the approach in the field has long been focused on intervention, such as surgery to widen congested blood vessels.
“We now have better coronary stents, but up to 50 per cent of people don’t survive their first heart attack,” he said.
“So there is a need for doctors to get ahead of the curve and predict heart disease risk early to stop that very first heart attack from even happening.”
That is why he and his colleagues conducted a study to assess the effectiveness of using ultrasound to predict future heart disease risk.
Completed last year, it uses a technique called carotid ultrasound protocol to measure the thickness of the carotid arterial wall in the neck and identify cholesterol deposits.
The thicker one’s arterial wall, the more susceptible one is to stroke and heart attack. Results from 276 patients show that one in four patients were mistakenly thought to be at low risk of getting heart disease in the long run. They would therefore benefit from preventive measures, said Dr Lee, who presented the findings at a congress last October in Prague, Czech Republic.
Such studies accompany the slew of genetic research in recent years that has identified genes linked to an array of health problems, from inherited diseases to obesity. Dr Liu observed that this trend “became phenomenal” only in the last five years.
In August, Agency of Science, Technology and Research (A*Star) boffins announced the results of an international study that revealed a staggering 95 genes linked to cholesterol levels.
Similarly, another team of A*Star scientists are set to embark on a study to identify new genes to allow for early identification of tuberculosis.
Principal investigator Gennaro De Libero of the Singapore Immunology Network (SIgN) under A*Star said novel approaches to identifying infectious diseases like tuberculosis are paramount as bacteria can quickly become resistant to existing antibiotics.
Professor De Libero said: “Discovering new antibiotics to treat the disease is not easy. It takes a long time to develop them for clinical use. Meanwhile, bacteria can rapidly become resistant to drugs.”
Hence, if one can identify the disease early, there is less time for the bacteria to morph into drug-resistant strains.
Examples of applications borne from such studies include the diagnostic test kit to distinguish severe acute respiratory syndrome (Sars) from other viral diseases, said Professor Paola Castagnoli, SIgN’s scientific director.
“With more sophisticated screening and genetic profiling techniques, the medical field will soon be able to offer a new kind of health care that is centred on individuals,” she said.
“Personalised health care will allow doctors to assess each person’s risk for developing a disease, as well as detect and treat the disease with the right drug before it causes irreversible damage,” she added.
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