Anxiety was never a problem for me until about six years ago, when I realised my worrying was getting out of hand. Most people can dismiss random thoughts about crashing the car or their children having accidents, but I couldn't. Instead they spiralled off into ever-more catastrophic "what ifs?" and triggered an overwhelmingly physical panic – my heart would lurch and I couldn't sit still.
So if I heard an ambulance screaming, I'd think one of my children might be in it, picture a range of nasty head injuries and an anxious wait in A&E. I had panic attacks when I was driving that made me feel I was losing control of the car. Or if my teenage sons were late home, I'd automatically fear the worst.
Then one morning, when I got up at 5am to catch a train, I collapsed. There was no obvious trigger, but my GP diagnosed a panic attack, and because I didn't want medication, referred me for counselling on the NHS. That helped a bit, but a year later I went back to the GP because my anxiety levels still didn't feel normal.
I was referred for cognitive behavioural therapy at the local NHS community mental health resource centre. There a trainee therapist diagnosed generalised anxiety disorder plus, halfway through therapy, post traumatic stress disorder, dating from a time many years ago when my boyfriend and I were mugged at knifepoint.
I'm not alone. Last week saw the launch of a report from the Mental Health Foundation (MHF) about anxiety, "In The Face Of Fear", which found that levels of anxiety in Britain have risen by 12 per cent since the early Nineties. It is estimated that four million people suffer from clinical anxiety, four times the number with depression. Anxiety often goes hand-in-hand with depression and other mental health problems, and according to figures from the Office of National Statistics, seven million people suffer anxiety overall. One in three will suffer panic attacks, which are often the precursor to more entrenched anxiety disorders, at some stage in their lives. Yet less than a quarter of anxiety sufferers receive any treatment, while less than five per cent receive psychological therapy.
So why are we getting more anxious? Nicky Lidbetter of the charity Anxiety UK reports a marked increase in calls since the start of the economic crisis. And the MHF report points to a "culture of fear"inflamed by the focus, by press and politicians, on terrorism, knife crime, MRSA and bird flu, and points out that the economic crisis does not only cause anxiety, but is also driven by it.
I'd always assumed that anxiety was a symptom of depression, but I didn't feel depressed at all. In fact they are quite distinct disorders, though they may occur together. The fact that there's a whole range of anxiety disorders, from agoraphobia to panic disorder and OCD, adds to the confusion.
According to Lidbetter, misdiagnosis is common, with many anxiety sufferers being prescribed anti-depressants, which can prove counter-productive. "Anxiety disorders are the poor relation of depression, and their severity is often underestimated," she says. "I think the general perception is that depression is more severe and perhaps more worthy of attention."
This may be because anxiety is largely hidden. Sufferers are often dismissed as the "worried well" because many carry on working and coping with everyday life, often self-medicating with alcohol or drugs.
Of course, non-worriers can't understand why anxiety is such a big deal. I've often struggled to explain to baffled friends how something that gives them no grief can make me feel so bad. Consultant psychiatrist Cosmo Hallstrom explains: "Anxiety can be a devastating condition. I've seen people whose lives have been crippled by it – they are housebound, they can't work, they underperform. It's one reason why people take to drink. But at the other end of the spectrum it may be a variant of normal. One of the problems is at which point we consider it crosses the boundary."
The context of general unease that most of us now inhabit can get to the most laid-back person: finances and jobs are less secure, we have high levels of debt, we measure our lives against those of celebrities, and we've got too much time to ponder how unfulfilled we feel.
"The commonsense assumption is that we're afraid of things that are dangerous," says Phillip Hodson of the British Association for Counselling and Psychotherapy. In fact, once there's a clear objective threat, anxiety is not so necessary because people have more sense of control. War tends to reduce anxiety, and suicide rates go down. The anxiety levels we've got now are because we haven't evolved to deal with the complex modern world. We're conditioned to expect we can have anything we want if we are successful, that we can do more than we can, that we don't need much sleep."
Graham Davey, professor of psychology at Sussex University, says: "These days news is often displayed in ways which are emotive and fearful when there's really no underlying threat, so it becomes very easy for people to exaggerate their fears. The problem is that while it's very easy to make someone anxious it's almost impossible to stop them being anxious by saying it's not a threat any more. Because people naturally adopt a 'better safe than sorry' attitude, and to stop feeling anxious they want objective evidence – usually from their own experience."
The "better safe than sorry" approach certainly rings bells with me. I reckon a root cause of my anxiety is the modern notion that we can do away with risk by anticipating every imaginable danger. I fell into a habit of expecting the worst when my children were young and more calamity-prone than most. It was a short step to believing I could prevent illness and accidents by anticipating every possible disaster: checking that switches were off, fires out, medicines out of reach and driving as little as possible. I didn't realise that my behaviour was creating more anxiety, not less.
Of course, some individuals are particularly prone to anxiety, thanks to genes or upbringing. High achievers, perfectionists and people-pleasers are also susceptible. But often it's a combination of vulnerability and bad luck that can affect anyone, according to Professor Paul Salkovskis, the psychologist who transformed lives on Channel 4's programme, House of Obsessive Compulsives.
Salkovskis, who is also clinical director of the Centre for Anxiety Disorders and Trauma, run by the Institute of Psychiatry, believes passionately that cognitive behavioural therapy is what many anxiety sufferers need, because unlike other therapies, its effectiveness has been carefully evaluated.
His view is endorsed by the Government, which is now at least some way towards achieving its election manifesto pledge of 10,000 new CBT therapists to be employed by the NHS to deal with mild to moderate mental ill-health.
Professor Salkovskis explains: "CBT is a type of applied common sense which works on a shared understanding between patient and therapist. It all boils down to the rather glib phrase we use to people who are anxious: 'Pull yourself together'. That's exactly what sufferers need, but they don't know how. We have evidence that CBT helps. We seek to have very brief treatments and to avoid the big pitfall of traditional psychotherapies, which is dependency."
CBT appeals because it's evidence-based, offers a quick, cheap fix (12 sessions average), and is dead practical – no self-indulgent Freudian delving into your childhood. But not everyone is so convinced. Nicky Lidbetter says, "CBT is a good therapy and it certainly works for some people. But it doesn't suit everybody. We must take a much more holistic approach and have a variety of other treatments on offer. Sometimes simple changes to lifestyle can really help."
I'm probably one of the people whom CBT doesn't suit that well. My therapist was a trainee, which bothered me a bit, and meant each session had to be taped for her supervisor. But I would have had to wait longer for a qualified therapist and I was grateful for any help.
The therapist focussed largely on the present, used diagrams to illustrate points and asked me to rate my beliefs on a scale of one to 100: it felt almost businesslike. I often got irritated by the style of questioning, which was intended to challenge my negative thoughts: I knew the "right" answer I was supposed to give, but it just didn't feel right to me.
For homework, I wrote lists of realistic alternatives to catastrophes I habitually imagined – that my son was lying in a pool of blood if he didn't answer his mobile, for example. Turning to these alternatives in a crisis proved a helpful tactic. But despite the therapist's best efforts, CBT did nothing to help my panic attacks while driving.
Five years on, the symptoms of anxiety have largely gone. Looking back, I can see that CBT helped more than I thought at the time, by setting in motion less negative ways of thinking. But other things have helped, too, such as halving my daily tea intake (which, to be fair, was the therapist's suggestion), keeping an eye on my blood sugar levels and having regular yoga sessions.
It could be, as some academics think, that seeing myself as an "anxiety sufferer" was unhelpful. Professor Graham Davey cites past studies that suggest that around 50 per cent of people who suffer bouts of anxiety can come out of it within two years without any structured form of treatment. He adds, "There is a tendency for people to go to the GP, quite rightly. But if the GP offers medication people then feel they have a disease or a medical problem, which can help it become entrenched. We mustn't medicalise anxiety." In that context, my therapist's parting shot – "What's so terrible about feeling bad?" – makes a lot more sense.
High anxiety: Do you have a problem?
* Are you haunted by totally unrealistic fears? That an armed burglar will break in while you're in the house on your own, for example, or you'll fall in front of a train, or you'll do something to hurt somebody? Everyone has random intrusive thoughts like these, but if you can't get them out of your head they can become a problem.
* Do you overestimate the chances of bad things happening and try to anticipate every possible risk?
* Do you often feel anxious for no particular reason you can identify?
* It's normal to worry about real problems, such as financial difficulties, a lump in your breast, a mistake at work. But does your anxiety continue after the initial cause has been resolved?
* Do you avoid situations or activities that have made you anxious in the past?
* If you're preparing for a job interview or a work presentation, do you go over every possible negative outcome?
* Do you hate feeling anxious? Some lucky people love risk and find the sensation almost exhilarating. But for others anxiety is so physically distressing that it interferes with daily life because they go out of their way to avoid it.
* Have you felt nervous or on edge most days over the past six months?
* Do you have problems falling asleep?
* Do you drink to escape anxiety?
* Are you a perfectionist with high standards who likes to be in control? If so, you're more likely to be affected.