SINGAPORE - Most people would assume that a physical condition should have a physical cause.
For example, diarrhoea should be caused by stomach flu or food poisoning - basically infections by bacteria or viruses.
But studies have shown that a mental malaise can also meddle with the body.
For instance, irritable bowel syndrome - which counts diarrhoea, pain and bloating among its symptoms - may possibly be triggered by psychiatric conditions such as depression.
When a person is depressed, the brain sends signals to the bowels, which then contract more strongly, causing irritable bowel syndrome.
Conversely, when the bowels are in pain, they transmit messages to the brain, which may then generate distress.
In fact, almost half of those with irritable bowel syndrome also have psychological problems, a recent study by Singapore General Hospital (SGH) has found.
In general, 14.3 per cent of people who have a chronic physical disease also have a mental one, the 2010 Singapore Mental Health Study reported.
On the other hand, more than half of all patients here with a mental illness also have a chronic physical illness, the study revealed.
But of these, only about 16 per cent are being treated for their psychological symptoms, possibly due to a stigma attached to mental illnesses.
Similarly, in the SGH study, only half of patients with irritable bowel syndrome and mental disorders accepted treatment for the latter.
But treating the mind could help the body and vice versa. So keep an open mind.
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