Accurate information about the incidence and prevalence of anxiety disorders is difficult to obtain; a survey by the Office of National Statistics (ONS 2000) found that 164 people per 1,000 had a neurotic disorder in the week before interview, which represents about 1 in 6 of all adults. They found that the most prevalent neurotic disorder among the population as a whole was mixed anxiety and depressive disorder (88 people per 1,000).
Anxiety disorders include generalised anxiety disorder, panic disorder, phobias, obsessive compulsive disorder (OCD) and post traumatic stress disorder (NICE 2007; Clinical Evidence 2007). They can be chronic and cause considerable distress and disability; if left untreated, are costly to both the individual and society (NICE 2007). As well as emotional symptoms such as worry, disturbed sleep, irritability and poor concentration, anxiety can cause physical symptoms such as sweating, nausea, diarrhoea, dry mouth, palpitations, shortness of breath, dizziness, cold hands, muscle tension and aches, trembling and twitching (American Psychiatric Association, 2000; WHO 2007). Also, the symptoms of many physical conditions can become worse with stress, for example, irritable bowel syndrome, migraines and tension headaches, and back pain (Clinical Evidence 2007).
Treatments recognised as useful for anxiety disorders include psychological therapies such as cognitive behavioural therapy (CBT) and applied relaxation, and medication such as some antidepressants and benzodiazepines (NICE 2007). All the drug treatments have side effects, and many may cause withdrawal or discontinuation symptoms (British National Formulary 2009).
The best evidence for acupuncture's effectiveness (Pikington 2010; Pilkington 2007) comes in specific acute anxiety situations such as around medical operations (Mora 2007; Wang 2007; Gioia 2006) or dentistry (Karst 2007).
There is surprisingly little research with a primary focus on acupuncture for generalised anxiety disorder. Those studies published so far are mostly small and methodologically flawed, hence the reluctance of reviewers to draw conclusions (Pilkington 2010; Pilkington 2007).
There are also preliminary positive findings for treating chronic anxiety associated with post-traumatic stress disorder (Hollifield 2007), substance misuse (Chae 2008; Courbasson 2007; Grusser 2005), eating disorders (Fogarty 2010), hyperventilation (Gibson 2007), asthma (Scheewe 2008), insomnia (Nordio 2008), post-stroke ((Wu 2008), musculo-skeletal pain (Hansson 2007; He 2005) and various other conditions where anxiety has been measured as a secondary rather than primary outcome.
Although the overall evidence is patchy, it does lie promisingly in a positive direction, and, given the very low level of side effects and lack of demonstrably superior outcomes from other interventions, acupuncture could be considered as one possible therapeutic option alongside the existing repertoire. (See table overleaf).
In general, acupuncture is believed to stimulate the nervous system and cause the release of neurochemical messenger molecules. The resulting biochemical changes influence the body's homeostatic mechanisms, thus promoting physical and emotional well-being.
Research has shown that acupuncture treatment may specifically benefit anxiety disorders and symptoms of anxiety by:
a) Acting on areas of the brain known to reduce sensitivity to pain and stress, as well as promoting relaxation and deactivating the 'analytical' brain, which is responsible for anxiety and worry (Hui 2010).
b) Regulating levels of neurotransmitters (or their modulators) and hormones such as serotonin, noradrenaline, dopamine, GABA, neuropeptide Y and ACTH; hence altering the brain's mood chemistry to help to combat negative affective states (Lee 2009; Samuels 2008; Zhou 2008; Yuan 2007).
c) Stimulating production of endogenous opioids that affect the autonomic nervous system (Arranz 2007). Stress activates the sympathetic nervous system, while acupuncture can activate the opposing parasympathetic nervous system, which initiates the relaxation response.
d) Reversing pathological changes in levels of inflammatory cytokines that are associated with anxiety (Arranz 2007)
e) Reversing stress-induced changes in behaviour and biochemistry (Kim 2009).
Acupuncture can be safely combined with conventional treatments such as medication or psycho-educational therapy, possibly enhancing their beneficial effects (Courbasson 2007) and reducing unwanted side-effects (Yuan 2007).
Source: British Acupuncture Council, Research Fact Sheets