ANXIETY DISORDERS This refers to a group of related disorders, the main types are:

BOUNDARIES OF ANXIETY DISORDER These conditions overlap

In other words, the symptoms of an anxiety disorder are not qualitatively different from normality, unlike say in a psychotic disorder, where the definitive symptoms such as delusions and hallucinations are not seen in people in good mental health.

After all, everyone worries, to a greater or lesser extent. The difference is that the person with an anxiety disorder worries to a pathological extent.

For many patients with clinically significant anxiety, it is apparent that they have always had high levels of anxiety. Such anxious characters are well known to all of us; if the anxiety is extreme and interferes with normal functioning, an anxious personality disorder F60.6 can be diagnosed.

ANXIETY AND DEPRESSION ALSO COEXIST. Some anxiety symptoms will be present in every person with depression. Some patients with mild anxiety, do not have low mood, but they are in a minority: most patients with diagnosable anxiety disorders will have coexisting mood symptoms.

Anxiety could to some extent be viewed as an early mild form of depression. In this model, anxiety is prominent in the early stages, but as the condition develops, low mood becomes more pronounced, and eventually comes to dominate the clinical picture. Accordingly, the diagnosis would then be one of a depressive illness.

HIERARCHY OF DIAGNOSIS Thus, just as a diagnosis of psychosis "trumps" a diagnosis of neurosis (anxiety, depression and other nonpsychotic conditions), so a diagnosis of depression is usually held to trump a diagnosis of anxiety. Hence it would not be usual to diagnose, say, a generalised anxiety disorder, as well as a depressive illness.

However, patients are sometimes diagnosed with more than one anxiety disorder, for example, generalised anxiety disorder and a phobic anxiety disorder.

FREQUENCY These conditions are common. Depending on how a "case" is defined- how low or high the bar is set- approximately 10% of the population at any one time (prevalence) has been found in community surveys to be diagnosable with an anxiety disorder. Up to 25% will have an anxiety disorder at some time during their life (lifetime prevalence).

DIFFERENTIAL DIAGNOSIS

• personality disorder: personality disorder is a more persistent condition than neurosis, and tends to present with disturbance of behaviour and social adjustment whereas neurosis presents with symptoms. The distinction between ìneurotic illnessî and ìneurotic personalityî is clearcut in some patients, for example if an anxiety state develops in a previously well-adjusted subject following a stressful event, but in other cases they co-exist, as when a habitually nervous dependent subject has an episode of particularly intense distress.
• other psychiatric illness such as major depression or alcoholism. If delusions or hallucinations are present, the main diagnosis must be a psychotic disorder, though the patient may have neurotic symptoms too
• medical illness, including systemic disorders such as thyrotoxicosis, and brain disorders such as temporal lobe epilepsy.
• substance misuse: alcohol, caffeine (in tea, coffee or cola drinks) or other drugs.
• stress reactions of normal degree. Anxiety is to be expected in certain situations and, if not excessive, may actually improve ability to cope. (The Yerkes-Dodson curve- performance improves with initial increases in stress; but beyond a certain point, further increases result in performance declining).
  

TYPES OF ANXIETY DISORDER The various kinds will now be described.

GENERALIZED ANXIETY DISORDER F41.1 This refers to a state of generalised worry, but the anxiety is general, rather than (as in phobic anxiety) being focussed on one particular feared objet or situation.

ICD 10 describes it as follows: "Anxiety that is generalized and persistent but not linked to any particular situation (i.e. it is "free-floating"). The dominant symptoms are variable but include complaints of

• persistent nervousness,
• trembling,
• muscular tensions,
• sweating,
• lightheadedness,
• palpitations,
• dizziness, and
• epigastric discomfort.

ñ cardiovascular symptoms such as tachycardia, palpitations
ACUTE STRESS REACTION ICD CODE F43.0. This is a transient, post-trauma reaction, which typically begins in minutes, and resolves in hours or days. The subject may be dazed and disorientated, with agitation, and emotional upset. There are prominent anxiety symptoms, e.g., sweating, pounding heart, flushing. It is present in up to a third of people after a road traffic accident. It usually resolves naturally, but if it does not can develop into PTSD (though PTSD may occur without the acute stress reaction).

ADJUSTMENT DISORDER ICD CODE F43.2: This is probably the commonest diagnosis following the occurrence of a significant life change or stressor. It consists of a short period of distress and emotional disturbance, with a mixture of depression and anxiety symptoms. It resolves within 6 months of onset (though a depressive subtype can persist for up to a year).

PANIC DISORDER F41.0 ICD10's description is as follows: "The essential feature is recurrent attacks of severe anxiety (panic), which are not restricted to any particular situation or set of circumstances and are therefore unpredictable. As with other anxiety disorders, the dominant symptoms include sudden onset of palpitations, chest pain, choking sensations, dizziness, and feelings of unreality (depersonalization or derealization). There is often also a secondary fear of dying, losing control, or going mad."

Panic disorder has only fairly recently been distinguished as a discrete diagnostic entity. The impetus for this has come from the US. SSRIs have been licenced as treatments for panic disorder, and have become widely prescribed for this indication.

Although the symptoms of panic sufferers are real, there is still room for doubt as to the validity of separating panic disorder as a discrete "tree" from the tangled forest of anxiety and depression.

SOCIAL PHOBIAS F40.1"Fear of scrutiny by other people leading to avoidance of social situations. More pervasive social phobias are usually associated with low self-esteem and fear of criticism. There will be avoidance distress and often panic and depression."

AGORAPHOBIA F 40.0 "A fairly well-defined cluster of phobias about being in a situation it would be hard to escape from, such as being away from home, entering shops, crowds and public places, or travelling alone in trains, buses or planes. Avoidance of the phobic situation is often prominent."

SPECIFIC (ISOLATED) PHOBIAS F40.2 "Phobias restricted to highly specific situations such as spiders, heights, thunder, etc. Though the triggering situation is discrete, contact with it can evoke panic as in agoraphobia or social phobia."

TRAVEL ANXIETY is a type of specific phobia, which is especially important after road traffic accidents; it has in the past been underdiagnosed. Features include:

Travel anxiety tends to be worse as a passenger, presumably because the subject feels out of control. There is often ìbackseat drivingî and ìphantom brakingî, i.e. stamping on a non-existent brake pedal.

POST-TRAUMATIC STRESS DISORDER (PTSD) F43.1 Psychiatry has always recognized syndromes such as shellshock as disorders following traumatic events. However, it was only in 1980 that DSM III described PTSD; it appears in ICD also, and the diagnosis has evolved significantly since its introduction.

The DSM sets out definitions of the various aspects necessary for a diagnosis of PTSD.

The traumatic event (DSM definition) must involve ìdirect personal experience of an event that involves actual or threatened death or serious injury, or other threat to one's physical integrity; or witnessing an event that involves death, injury, or a threat to the physical integrity of another person; or learning about unexpected or violent death, serious harm, or threat of death or injury experienced by a family member or other close associateî (criterion A1)

The personís response (criterion A2) must have involved ìintense fear, helplessness, or horrorî.

There are 3 cardinal groups of symptoms:

Finally, the symptoms must be present for more than 1 month (Criterion E), and the disturbance must cause clinically significant distress or impairment in social, occupational, or other important areas of functioning (Criterion F).

PTSD: examples of stressors sufficient to qualify for Criterion A:

ï Violent physical assault
ï Sexual assault or abuse
ï Combat
ï Serious accidents
ï Natural or man-made disasters
ï Diagnosis of a life-threatening illness

HOW COMMON IS PTSD? Community surveys show that exposure to traumatic events is the rule rather than the exception, having happened to up to 90% of subjects at some time. PTSD is much less common, being found in less than 10% in the same surveys. This apparent discrepancy is because:

As would be expected, rates of PTSD after accidents are somewhat higher, and figures of approximately 20% at 3 months and 15% at one year have been suggested amongst road traffic accident victims who attend hospital.

WHAT ABOUT THE "POST" IN PTSD? Since the concept was formulated, it has become clear that the delay between trauma and onset of symptoms- to which the "post" in PTSD refers, only occurs in a minority of patients (e.g. 10-20%). The vast majority develop symptoms straight away.

OBSESSIVE-COMPULSIVE DISORDERS The patient feels a strong obsession to ruminate on a thought topic, and/or compulsion to carry out some practical action.

The patient knows that these symptoms come from within the self, in other words that these are their own thoughts and actions. (Hence, they are quite distinct from the experiences of thought insertion or delusions of control, sometimes seen in schizophrenia.)

Nevertheless, the patient knows that the thought or actions are irrational, and that they are contrary to their own beliefs and well-being; they are sometimes described as ìego dystonicî. The patient realises that the thoughts and actions are inappropriate and should be under personal control, but attempts to resist them cause great anxiety and are usually not successful.

Common types of obsessional thinking include:
ñ fears of harming others (very rarely put into practice) or contracting a serious disease
ñ sexual or blasphemous thoughts which are abhorrent to the patient
ñ ruminations on insoluble problems in mathematics or philosophy.

Common types of compulsive rituals include:
ñ checking, for example that the door is locked or lights switched off
ñ washing, often carried out in order to allay fears of contamination or harm.

Patients may spend so much time on their rituals that normal daily activities are neglected. Compulsive hand-washers often develop skin rashes. The illness is particularly distressing because the patients are so well aware their symptoms are absurd.

Community surveys indicate that obsessive-compulsive disorder is present in 2ñ3% of the general population and, in contrast to other neurotic disorders, is equally common in both sexes.

Similar symptoms may occur as a sequel to organic brain disease, and schizophrenic phenomena such as thought interference, passivity experiences and delusions may also cause diagnostic confusion. However, in organic and schizophrenic cases, insight and resistance are usually absent.

Behaviour therapy with exposure and response prevention, and antidepressants, especially those like clomipramine and SSRIs which act on 5-HT systems, are effective treatments.

RECOGNITION AND MANAGEMENT OF ANXIETY DISORDERS Regarding screening, diagnosis and treatment, the various anxiety disorders will now be discussed together, since the similarities between them are much more prominent than the differences.

SCREENING AND ASSESSMENT There are various ways in which people can be screened for anxiety and depression. This would obviously include awareness on the part of the clinician, to look for possible cases, especially among high risk groups, such as those who have been involved in accidents or who are in hospital with physical conditions. More formal means of screening would include the use of paper (or computerised) tests such as the:

though there are many others.

There is variation in the extent to which such screening and assessment tools are used in clinical and in medicolegal practice. Some psychologists, in particular, rely heavily on them. Many psychiatrists seldom use them.

The problem with these scales, at any rate in a medicolegal setting, is that few, if any, have been validated for such use (as against the research or clinical setting, where there are well established procedures for assessing the validity and reliability and other performance characteristics of proposed new psychometric instruments.).

DIAGNOSIS OF ANXIETY DISORDERS In practice, the diagnosis of an anxiety disorder is a clinical one. The characteristic symptoms and signs, as described above, will be looked for, essentially in a process of pattern recognition.

DIFFERENTIAL DIAGNOSIS Anxiety disorders must be distinguished from the following conditions:

INVESTIGATION There is a need, as always in psychiatry, therefore, for patients with a presumptive diagnosis of an anxiety disorder to have a full physical examination to exclude the presence of underlying physical disease. This will normally be done by the patient's GP, or have been covered during hospital treatment or assessment by other experts. However, the assessing psychiatrist must satisfy himself that it has been done.

Blood tests to exclude anaemia, overactive thyroid and other medical conditions are necessary.

TREATMENT General principles of medication treatment and of psychological treatment are discussed in those chapters. I will now discuss how these are applied in the specific case of anxiety disorders.

Simple explanation and advice are helpful, to most patients, and may themselves be sufficient in milder transient episodes.

Self-help through reading, sometimes dignified with the term bibliotherapy, can be useful as well, and Helen Kennerley's Overcoming Anxiety is widely recommended.

MEDICATION Use of medication is the most available treatment if the patient consults their GP.

anxiolytic drugs such as benzodiazepines are best taken only when symptoms actually occur, or shortly before the patient has to face an anxiety-provoking situation. Regular medication encourages tolerance and dependence, and for this reason benzodiazepines are recommended for short-term use only. Unfortunately, because of fears of addiction, these drugs may now in danger of being underused.

In patients with stable personality, with a short-term stress such as acute distress following bereavement to deal with, they can be a safe and effective treatment.
There is also a small minority of chronic severe sufferers who have tried and failed with other treatments, long-term benzodiazepine treatment may form the least worst therapeutic option.

antidepressants: sedative tricyclics such as trimpramine are often given in anxiety disorders, though are not generally licensed for this indication. Their full benefit may take several weeks in depression, but their useful hypnotic and anxiolytic properties are immediate and dose-related. Imipramine is effective in panic disorder. MAOIs should be tried if other antidepressant classes.

SSRIs are widely used in general practice; some patients probably benefit. However, in some patients they can exacerbate anxiety, with troublesome agitation and gastrointestinal upset; the problem is so significant that some have advised ìcoveringî a newly started SSRU with a second drug such as the notably sedative trazodone or a benzodiazepine. Unfortunately, it is not possible to predict which patients will experience these adverse effects.

Therefore, SSRIs are not the preferred option. Trazodone, trimpramine, or, amongst the newer drugs, mirtazepine, have predictable and dose-related anxiolytic effects, and are much more suitable.

beta-blockers such as propranolol can help to control the physical symptoms of anxiety, such as palpitations; they are useful in mild anxiety states in some patients, especially in primary care. They are seldom effective in severe anxiety states, as they have little effect on the psychic aspects of anxiety.
buspirone is popular in the US, but less so in the UK; in practice, its efficacy seems weak.

antihistamines such as promethazine have useful sedative, and hence anxiolytic properties. It is worth remembering that these drugs were the drug class from which the original antipsychotics were developed; they have always been prescribed as sedatives to some extent, for example, in children, and in anaesthetic premedication. They are now recommended as an alternative following the overprescribing of benzodiazepines.

antipsychotic drugs in low dose: small amounts of chlorpromazine or, more recently, olanzepine, are widely used; they carry their own risks, for example of extrapyramidal side-effects, weight gain and so forth, though these are very small in the small doses usually indicated.

PSYCHOLOGICAL TREATMENT The ordinary forms of counselling- the sort widely available, sometimes in GP surgeries- are popular with patients. However, there is little evidence of effectiveness; the evidence base is for structured forms of psychological treatment such as behaviour therapy, and CBT.

As an illustration, let us take the example of the treatment of a specific phobia, for example, of water, using cognitive behavioural principles. Components of treatment would include the following:

*by anxiety hierarchy is meant a series of situations in which the person is exposed to the feared stimulus in a gradually increasing manner. In this case, it might include

As will readily be surmised, the approach is common sense and practical and can to some extent be systematised; therefore computerised versions have been developed, both for anxiety, and for depression. NICE has recently opined that there is evidence of effectiveness, and that they should be considered for clinical use.

However, it seems unlikely that they will completely replace the need for skilled therapists; it seems more likely to me that they will form a component of therapy, but that there will still be a need for the therapist to start the patient off and support them during the treatment.

PREVENTION OF PTSD "The road to hell is paved with good intentions" might be our watchword here, at least in respect of well-meaning efforts to prevent PTSD.

Efforts to encourage- or even require- those who have been exposed to trauma to talk things over with a counsellor or other adviser, either individually or in a group, come under the heading of debriefing. To many, both in the mental health professions and in the wider community, it would seem natural and obvious that such a laudable endeavour would be helpful. After all, "it's good to talk".

Unfortunately, the evidence shows that this can actually be harmful, increasing rates of post-traumatic stress disorder at follow up- the exact opposite of what it was designed to do.

It seems that most people actually do better on their own than if they are directed down a mental health route; informal support mechanisms, whether that be going to the pub with workmates, or having a good cry with loved ones, seem more healthy. Accordingly, the NICE PTSD guideline advises against its routine use.

TREATMENT OF PTSD "All PTSD sufferers should be offered a course of trauma-focused psychological treatment (trauma-focused cognitive behavioural therapy or eye movement desensitisation and reprocessing)", recommends the NICE PTSD guideline. As regards CBT, this is a laudable sentiment, but is wishful thinking: there are just not enough therapists.

As regards EMDR (which stands for "eye movement desensitisation and reprocessing"), this controversial treatment is also regarded by NICE as an evidence based treatment, in spite of the fact that no one has a great idea of how it might work.

Various medications- especially antidepressants- are also effective in PTSD, though only paroxetine is specifically licensed for this indication.

PROGNOSIS It is very difficult to give a numerical prognosis, as the category of anxiety disorders is so multifarious. The traditional "rule of thirds" is probably the most useful summary for present purposes: one third recover, one third improve, but not completely, and a further third do badly.