By Poon Chian Hui

The human body is hard-wired to respond to fear. The instant a threat is sensed, the brain automatically switches to defence mode.

Adrenaline is released. Breathing speeds up. The heart beats faster. Muscles tighten as the body is poised to either fight or flee.

But things can get tricky when the fear response, commonly known as 'fight or flight', spins out of control.

Irrational fear can morph into anxiety disorders, such as phobia, obsessive-compulsive disorder (OCD) and panic attack.

'People with anxiety disorders always have a premonition that something will go wrong,' said Dr Tommy Tan, a consultant psychiatrist at Tommy Tan Psychiatric Clinic, Novena Medical Center. 'A key feature of this excessive fear is that they overreact to the situation.'

Anxiety disorders are the most common form of mental illness in Singapore, with about 10 per cent of people here affected, statistics from the Health Promotion Board show. They include phobia, OCD, panic disorder, post-traumatic stress disorder and generalised anxiety disorder. However, there are distinct differences.

A phobia is a morbid fear of an object, situation or activity but it usually causes little real danger, said DrLim Yun Chin, a psychiatrist at Raffles Hospital.

'Unlike the brief anxiety that most people feel when they give a speech, for example, a phobia is long-lasting and causes intense distress,' he said.

'If a person fears snakes, even a picture of a snake will trigger an intense reaction,' said Dr Tan.

OCD, on the other hand, is where repetitive, fearful thoughts (obsession) lead to a ritualistic action (compulsion), said DrAdrian Wang, a consultant psychiatrist at Gleneagles Medical Centre.

'It's extreme perfectionism. Sufferers are compelled to do certain things meticulously; that's why they keep repeating an action,' he said.

Otherwise, they start having catastrophic thoughts, said DrTan.

'They think that something bad will happen if they fail to do something thoroughly,' he said.

For example, a person obsessed with cleanliness might imagine getting a disease from germs if he were to stop cleaning. He then imagines spreading the illness to his family and friends, and so on.

Interestingly, sufferers are often aware that their thoughts and actions are illogical. They just cannot help themselves, said DrTan.

The lack of control is similar in a panic attack, which is a period of sudden, overwhelming anxiety that occurs without warning, resulting in symptoms like rapid heartbeat, perspiration and dizziness.

Panic attacks are often linked to agoraphobia, the fear of open spaces where escape is difficult, said DrLim.

A post-traumatic stress disorder is, as its name suggests, caused by an emotional or life-threatening event. The person later has anxiety symptoms like flashbacks. As for generalised anxiety disorder, it refers to a persistent fear or worry over matters like finances. Sufferers tend to incur health problems from the constant tension.

Although phobias may be more common, partly due to the huge range of possibilities - a person can have a specific phobia of anything ranging from snakes to dentists - OCDs may have a greater impact on a person's life, said DrWang.

'Many people live with their phobias by simply avoiding the object of fear,' he said. 'For example, a person who fears snakes can avoid going to the zoo.'

An OCD may, however, disrupt one's life to a greater extent. 'While some may be barely bothered, others spend a lot of time on compulsive actions every day,' said Dr Lim.

Dr Tan agrees. 'The illness itself may not be distressing but the consequences often are,' he said. 'I had a patient who was sacked because he spent hours in the toilet and was always late for work.'

There are five types of OCD sufferers: washers, checkers, orderers, hoarders and obsessionals, based on the different obsessions and accompanying compulsions.

While there are no proven causes, anxiety disorders are believed to be caused by a combination of genetics, brain chemistry and life experiences, said Dr Lim.

For example, phobias may stem from a traumatic incident. DrTan recalled a patient whose coach to Malaysia got into an accident. She later developed a serious phobia of taking buses to Malaysia.

In addition, brain imaging studies have shown that OCD sufferers display patterns of brain activity that differ from those without or have other mental illnesses, said Dr Lim.

In general, anxiety disorders are treated with anti-depressant medication and counselling therapy.

A common method of therapy is exposure therapy, where patients are exposed to the source of anxiety in gradual increments. They build tolerance to the point when they are able to overcome the anxiety.

But how can someone tell if he has an anxiety problem?

If something persistently causes distress to you, it would be wise to seek professional advice, said Dr Tan.

Likewise if you are unable to do daily tasks or work properly due to the anxiety, said Dr Wang.

'Most anxiety disorders can be cured,' he said. 'Some may last for a long time but treatment can improve the current situation significantly.'

Otherwise, an anxiety disorder may lead to other problems, such as depression, said Dr Lim.

chpoon@sph.com.sg

This article was first published in Mind Your Body, The Straits Times.

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