IT'S THE MIDDLE of the night and Paula wakes up in a cold sweat. The space next to her, normally occupied by her husband, is empty. He's on another business trip to Sydney and will be home in a few days. But as the seconds tick away, Paula becomes increasingly convinced she'll never see him again. 'I told myself that I'd never hear from him again and I'd end up alone,' Paula says. 'Even after he called me, my chest felt so tight I couldn't breathe. I felt as if I was going out of my mind.'' Mark works for a hotel management company. When he arrived late for an important meeting and his boss looked angry, Mark felt faint and had to leave the room. Normally level-headed, he stumbled to his desk convinced he'd never work again. After a hectic day at her new business, Celine was shopping late one night when she suddenly worried that her baby was choking to death at home. Her heart began to beat so fast she thought she was having a heart attack. She screamed for help and was taken to hospital. At home, her baby was sleeping peacefully. Paula, Mark and Celine all had panic attacks - when normal worries escalate out of control, triggering disturbing physical symptoms that, in turn, interfere with daily life and relationships. Experts say that as many as one in 20 people suffer panic attacks. At a recent gathering in Chicago of the International Society for Traumatic Stress Studies (ISTSS), delegates suggested that, in places that have experienced terrifying events - such as New York after the World Trade Centre attacks, Hong Kong and other parts of China after Sars - leftover fears from such major events build up and erupt when people are faced with seemingly trivial inconveniences, such as screaming children or just being caught in a traffic jam. For Jonathan, the trigger was his evening commute. 'Every night since Sars, when I took the ferry to get home, I had trouble breathing in the crowd of people and felt like pushing them away,'' he said. This normally calm man was relieved to identify his problems as a panic attack, exacerbated by a lingering fear from the Sars epidemic that being surrounded by strangers could endanger his life. Pounding heart, choking, breathing difficulties, sweating, dizziness and intense stomach aches are some of the symptoms Jonathan and others experience in a panic attack. Some say they feel as if they've left their bodies and are watching themselves. Often the symptoms are so real that people become convinced they are having a heart attack, losing their minds or even going to die. In Asia, where people stereotypically internalise emotions more than in the west, panic attacks are more common. The whole frightening experience can take just a few seconds and can strike out of the blue. Fear of an attack can get so extreme that people stop going to work or school, or even leaving the house. Understandably, relationships can also suffer. Statistics show that twice as many women as men suffer panic attacks, with experts blaming this on female personality traits such as anxiety, passiveness and feeling less in control of their lives, compared with men. Other studies suggest women are more sensitive and react more readily to adverse stimuli in their environment. While stricken women may think, 'I'm going crazy', men tend to tough it out or treat it strictly as a physical problem. Children and young people, too, are vulnerable - especially after difficult times, such as Sars or September 11. About half of all panic disorders develop before the age of 24. In these cases, the trigger is often an early trauma, such as the death of a parent, a near-accident or a major upset at school. Researchers at the ISTSS meeting reported that children's symptoms commonly showed up 18 months after community-wide traumatic experiences. One study showed that traumatised toddlers may function well for years until a reminder of the event surfaces, as in the case of an 11-year-old who, when she was two, had seen her mother murdered, but showed no symptoms for nine years. Such reports presented at the ISTSS urge early identification and intervention with youngsters to prevent exaggerated problems, post-traumatic stress and panic in later years. The difficulty is that children's panic is difficult to identify and treat because they can't - or won't - express feelings directly. Instead, fears are manifested in psychosomatic complaints (like stomach pains and headaches), sleeping trouble, over-attachment to parents or withdrawal, aggressive behaviour, and even regressing to thumb-sucking or bedwetting. Traumatised parents can also be blamed for inciting fears in children by transferring their fears and anxieties. The consensus among scientists is that panic seems to be a combination of heredity, brain activity (over-activation of a small structure called the amygdala), stressful life situations (work overload, loss of a loved one, illness or childbirth) with exaggerated thoughts. Panic attacks - such as Paula's, triggered by her husband's absence - are 'separation anxiety', often traced to early childhood. As a child, Paula refused to go to school, fearing her parents would die in her absence. This is consistent with early cognitive development, when things apparently cease to exist unless they are visible. Fear of losing love, security or respect is another common cause of panic attacks, as in Mark's case, when an ego blow at work shattered his self-esteem, or when you are afraid to give a speech before a group for fear of being critically judged. Women can develop a conflict over being a capable mother while pursuing career success or harbour a need to be taken care of. Burdened by responsibility and deprivation of nurture, they can succumb to panic. Super-controllers - men and women highly in charge of their life - are also vulnerable when overwhelmed with work or when some aspect of their lives collapses. With five big projects to finish by the end of a week, Celine was so stressed that, when she couldn't find her notes for a meeting, she tore out all her files and fell on the floor crying. One study of thousands of patients in an anxiety treatment centre showed that adults with panic were overprotected or distant as children; had too much responsibility as children because a parent was an alcoholic, ill or phobic; felt threatened by separation; or were sexually abused. As a result, they grew up unable to resolve problems - which, in turn, can cause panic attacks at the slightest challenge. For these people, traumatic events such as Sars, have a silver lining because they give them an excuse to seek help for emotional problems they've tried to keep hidden for years. Ellen Stevenson, chief of clinical services at the Department of Psychiatry at Columbia Medical Centre, discovered that many police - normally reluctant to seek help from department counsellors - readily called a hotline for help after the attack on the World Trade Towers. 'As long as they could blame the shock of 9/11, they felt comfortable to open up and talk about arguments at home or frustrations on the job,'' she says. Judy Kuriansky is a clinical psychologist and sex therapist. She is the assistant clinical professor of psychiatry at Columbia University Medical School and a lecturer with Hong Kong University's Space School of Professional and Continuing Education. Her books include The Complete Idiot's Guide to A Healthy Relationship.