Most of us are familiar with the dry mouth, racing heart and knotted stomach that are the hallmarks of feeling anxious. Usually this is a fleeting response to danger and uncertainty. In some people, however, the state of high alert won’t switch off. Their anxiety becomes so draining it is impossible to leave the house or function in daily life.
One woman feels agitated and lightheaded each morning when she wakes. She worries about the accidents that might befall her if she travels to work, but also about what would happen if she had nothing planned for the day. Another avoids work, friends or even walking her dog in case it triggers another panic attack. One man finds it difficult to pick up the phone for fear he will mash his words and be misunderstood.
These are real cases of people who have sought help for their anxiety. Their experiences aren’t unusual. Anxiety disorders – including generalised anxiety, panic attacks, social anxiety and phobias – are the most prevalent mental health problem in the US and Europe, and a growing number of reports from other regions suggest they could be a global concern. In the West, they cost healthcare systems more than $40 billion each year. On average 1 in 6 of us will contend with an anxiety disorder at some stage in our lives – women more than men.
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The damage is real. Anxiety disorders have been linked to depression and increased substance abuse, particularly of alcohol. A recent study found that men who have anxiety disorders are twice as likely to die from cancer as men who don’t, even when factors such as drinking and smoking are taken into account.
So what is the cause of all this anxiety? Is there more of it about, and what is the best way to tackle it?
How much anxiety is normal?
Anxiety is a natural response that evolved over millions of years to make us more vigilant and prime our bodies to flee danger. But feeling anxious because you heard a noise on a dark street isn’t the same thing as having an anxiety disorder. “The key thing we look for in the clinic is whether anxiety is interfering with a person’s day-to-day life, or causing them a lot of distress,” says Nick Grey of King’s College London.
To clinical psychologists like Grey, “maladaptive beliefs” are a hallmark of anxiety disorders and are often used to diagnose the type of anxiety someone has. In social anxiety disorder, the most common anxiety disorder, you might believe that blushing will result in people laughing at or shunning you. People with this type of disorder experience persistent and overwhelming fear before, during and after social events.
If you have panic disorder, you might assume that you are having a heart attack if your heart starts to race. The physical symptoms of anxiety – a pounding heart, difficulty breathing, feeling dizzy or flushed – will then come on in a rush. Everyone can experience such panic attacks from time to time, but in panic disorder the attacks are regular and become a source of anxiety themselves.
Other maladaptive beliefs are less specific. Generalised anxiety disorder is characterised by chronic worrying about a range of different events or activities, for at least six months. If you have this condition, the belief driving your anxiety could, for example, be the feeling it’s your job to take care of other people, or that you have responsibilities that you must meet at all cost. To decide who to refer for further treatment, doctors might use a tool called the GAD7 test.
“Anxiety disorders are the most prevalent mental health problem in the west“
Are we more anxious than we used to be?
The Roman politician and philosopher Cicero was among the first to define anxiety as an illness, in the 1st century BC. Our current medical definition dates to 1980, when the American Psychological Association estimated that between 2 and 4 per cent of people in the US had an anxiety disorder. Today, some studies suggest it’s more like 18 per cent in the US and 14 per cent in Europe.
Such figures have led some to conclude we are in the midst of an anxiety epidemic, fuelled by factors such as economic anxiety, social media and the rise of the 24-hour society. The reality is more complex. The apparent increase is probably due to changes in diagnostics over the years, which make long-term comparisons difficult. “I think we are becoming more stressed and that has to do with having a lot of demands on our time,” says Jennifer Wild of the Oxford Centre for Anxiety Disorder and Trauma in the UK. “But if you’re looking at the prevalence of anxiety disorders, they haven’t gone up.”
There is tentative evidence to support this conclusion. For instance, Olivia Remes and her colleagues at the University of Cambridge found little overall change in the number of people around the world affected by anxiety disorders between 1990 and 2010. Their meta-analysis, published earlier this year, found that roughly 1 in 10 people experience anxiety at any given time, and about 17 per cent are likely to experience it at some stage in their lives.
Remes found that adults under the age of 35 were disproportionately affected by anxiety. Similarly, Borwin Bandelow and Sophie Michaelis at the University Medical Centre in Göttingen, Germany, found evidence that the prevalence of most anxiety disorders peaks in 18 to 34-year-olds before dropping off again. Specific phobias were the exception, peaking in 35 to 50-year-olds.
Even if the overall prevalence of anxiety disorders hasn’t increased, anecdotal evidence suggests that the type of anxiety people are experiencing is changing. When Nicky Lidbetter, chief executive of Anxiety UK, joined the charity 20 years ago, the majority of queries they received were from people with panic disorder or agoraphobia, an extreme fear of open spaces. “Nowadays it is health anxiety [hypochondria] and social anxiety,” she says.
What causes the symptoms of anxiety?
Although we are still a long way from fully understanding what is going on in an anxious brain, recent studies offer some insights into why anxiety seems to take over in some people. Central to it all is the amygdala, a brain region that processes our emotions and triggers the release of the hormones responsible for the fight-or-flight response.
The amygdala is linked to parts of the prefrontal and anterior cingulate cortex that process social information and help us make decisions (see diagram). During bouts of everyday anxiety, this brain circuit switches on and then off again – but Oliver Robinson at University College London and his colleagues have shown that in people with anxiety disorders it seems to get stuck in the on position. “We think it might be amplifying negative information in your surroundings to make sure you pay attention to it, and triggering a fight-or-flight response so you’ll run away,” says Robinson.
Studies suggest that fear memories stored in the amygdala prime us to respond to threats we have previously experienced. This response is normally kept in check by a parallel circuit: in healthy people, inputs from the prefrontal cortex can temper our learned response and even overwrite it with new memories. Occasionally the system fails, however. Psychiatrists have found that war veterans with post-traumatic stress disorder – a kind of anxiety disorder – have abnormally low levels of activity in their prefrontal cortex, and unusually high levels in their amygdala.
Ultimately, an overactive amygdala appears to hype up the familiar symptoms of the fight-or-flight response by stimulating a network of hormonal glands and brain regions called the “HPA axis” – causing rapid heart rate and breathing, a dry mouth, shaking and tense muscles. The fight-or-flight response also has less obvious effects, like slowing digestion and making us more susceptible to pain.
Understanding these interactions will help design better treatments. For instance, Robinson’s circuit switches on when levels of the neurotransmitter serotonin are low, which could explain why a class of antidepressants known as SSRIs can reduce anxiety levels: they increase the availability of serotonin in the brain. “Maybe serotonin is applying the brakes to this particular circuitry,” says Robinson.
Are some people naturally more anxious than others?
Do you calmly navigate life’s bumps or agonise at every turn? Psychologists have long argued that people have innate dispositions that explain how we act, one of which is neuroticism – or proneness to anxiety. A recent study of more than 106,000 people identified nine regions of the genome that seem to correlate with neuroticism. Some of these contain genes previously linked to anxious behaviour, such as CRHR1, which regulates release of the stress hormone cortisol. The same gene has also been associated with anxiety-related behaviour in mice, and panic disorder in humans.
Some people are therefore naturally more prone to anxiety. But even if you are a natural-born neurotic, this doesn’t mean you will develop an anxiety disorder. “Having a high level of dispositional anxiety is a risk factor for developing an anxiety disorder, but you can be highly anxious and completely healthy,” says Marcus Munafo, a behavioural neuroscientist at the University of Bristol, UK.
Your age (see “Are we more anxious than we used to be”) and sex are factors at play. Population studies show that women are about twice as likely to develop an anxiety disorder as men. In part, this may be down to hormones and their influence on the brain. The surges in oestrogen and progesterone that occur during pregnancy, for instance, have been linked to obsessive compulsive disorder, an anxiety-related condition. Remes points out that there may be other explanations too, such as the fact that women tend to cope with stressful situations differently. “They worry a lot more about what’s going to happen, which can increase their anxiety,” she says. “Men tend to take a more problem-focused approach.”
“Being a natural-born neurotic doesn’t mean you’ll develop anxiety disorder“
What’s the best way to tackle an anxiety disorder?
If you have an anxiety disorder, cognitive behavioural therapy (CBT) is likely to be the first recommended treatment. Considered the gold standard in treatment, it aims to address the maladaptive beliefs that drive your anxiety. Once they have been identified, CBT helps you challenge them. “If someone is worried about blushing, we might put blusher all over their face and make them have conversations with people to see that they generally don’t even notice,” says Wild. “For panic disorder, you might get someone to run up and down the stairs, to show them that even if they do an extreme behaviour, they aren’t going to have a heart attack.”
A shortage of therapists has spurred the development of online delivery of CBT. In a pilot study of 11 people with social anxiety disorder, Wild found that nine of them responded to online CBT and seven achieved remission, although it is too early to say if this is better or worse than face-to-face therapy.
Therapy isn’t for everyone, however. Some people don’t respond well to therapists or analysing their own behaviour. In this case, a second line of attack is drugs, which can redress chemical imbalances in the brain.
Several studies have shown that people with panic disorder and generalised anxiety disorder tend to have lower levels of a neurotransmitter called GABA, which is thought to help the amygdala filter out unthreatening stimuli. Blocking GABA production in rats has been shown to trigger anxiety-like symptoms.
Benzodiazepines, a class of common anti-anxiety drugs which includes Valium, work on this system but are highly addictive. Doctors may feel more comfortable prescribing antidepressants, says Lidbetter. These can help with the physiology of anxiety as well as the secondary symptoms, which often include depression. However, Lidbetter believes that this is a field that needs to move on. “We need a new benzodiazepine-type drug – something which isn’t addictive,” she says.
Exercise can help with day-to-day anxiety and is a helpful additional strategy for people with anxiety disorders. It triggers the release of mood-boosting endorphins, and forces you to concentrate on something other than your own thoughts. Then there’s diet. A team led by Phil Burnet at the University of Oxford has found that taking a fibre-rich supplement to encourage the growth of beneficial gut bacteria for three weeks caused people to pay more attention to positive words on a computer screen and less attention to negative ones. Upon waking each morning, the volunteers also had lower levels of the stress hormone cortisol in their blood. “We saw a small but significant effect on the underlying psychological mechanisms that contribute to anxiety,” says Burnet.
Modern life may be packed with events outside your control, seemingly designed to foster anxiety and self-doubt. The important thing is to recognise the symptoms and do something about them.
This article appeared in print under the headline “Worry…”