2COMMON MENTAL HEALTH DISORDERS

Depression

Depression refers to a wide range of mental health problems characterised by the absence of a positive affect (a loss of interest and enjoyment in ordinary things and experiences), low mood and a range of associated emotional, cognitive, physical and behavioural symptoms. Distinguishing the mood changes between clinically significant degrees of depression (for example, major depression) and those occurring ‘normally’ remains problematic and it is best to consider the symptoms of depression as occurring on a continuum of severity (Lewinsohn et al., 2000).

Commonly, mood and affect in a major depressive illness are unreactive to circumstance remaining low throughout the course of each day, although for some people mood varies diurnally, with gradual improvement throughout the day only to return to a low mood on waking. In other cases a person's mood may be reactive to positive experiences and events, although these elevations in mood are not sustained with depressive feelings often quickly re-emerging (Andrews & Jenkins, 1999).

Behavioural and physical symptoms typically include tearfulness, irritability, social withdrawal, an exacerbation of pre-existing pains, and pains secondary to increased muscle tension (Gerber et al., 1992). A lack of libido, fatigue and diminished activity are also common, although agitation and marked anxiety can frequently occur. Typically there is reduced sleep and lowered appetite (sometimes leading to significant weight loss), but some people sleep more than usual and have an increase in appetite. A loss of interest and enjoyment in everyday life, and feelings of guilt, worthlessness and deserved punishment are common, as are lowered self-esteem, loss of confidence, feelings of helplessness, suicidal ideation and attempts at self-harm or suicide. Cognitive changes include poor concentration and reduced attention, pessimistic and recurrently negative thoughts about oneself, one's past and the future, mental slowing and rumination (Cassano & Fava, 2002).

Generalised anxiety disorder

The essential feature of GAD is excessive anxiety and worry (apprehensive expectation), occurring on more days than not for a period of at least 6 months, about a number of events or activities. The person with GAD finds it difficult to control the anxiety and worry, which is often accompanied by restlessness, being easily fatigued, having difficulty concentrating, irritability, muscle tension and disturbed sleep (Brown et al., 2001).

The focus of the anxiety and worry in GAD is not confined to features of another disorder, for example having panic attacks (as in panic disorder) or being embarrassed in public (as in social anxiety disorder). Some people with GAD may become excessively apprehensive about the outcome of routine activities, in particular those associated with the health of or separation from loved ones. Some people often anticipate a catastrophic outcome from a mild physical symptom or a side effect of medication. Demoralisation is said to be a common consequence, with many individuals becoming discouraged, ashamed and unhappy about the difficulties of carrying out their normal routines. GAD is often comorbid with depression and this can make accurate diagnosis problematic (Wittchen et al., 2002).

Panic disorder

People with panic disorder report intermittent apprehension, and panic attacks (attacks of sudden short-lived anxiety) in relation to particular situations or spontaneous panic attacks, with no apparent cause. They often take action to avoid being in particular situations in order to prevent those feelings, which may develop into agoraphobia (Breier et al., 1986).

The frequency and severity of panic attacks varies widely. Situational triggers for panic attacks can be external (for example, a phobic object or situation) or internal (physiological arousal). A panic attack may be unexpected (spontaneous or uncued), that is, one that an individual does not immediately associate with a situational trigger.

The essential feature of agoraphobia is anxiety about being in places or situations from which escape might be difficult, embarrassing or in which help may not be available in the event of having a panic attack. This anxiety is said to typically lead to a pervasive avoidance of a variety of situations that may include: being alone outside the home or being home alone; being in a crowd of people; travelling by car or bus; being in a particular place, such as on a bridge or in a lift.

Obsessive-compulsive disorder

OCD is characterised by the presence of either obsessions or compulsions, but commonly both. An obsession is defined as an unwanted intrusive thought, image or urge that repeatedly enters the person's mind. Obsessions are distressing, but are acknowledged as originating in the person's mind and not imposed by an external agency. They are usually regarded by the individual as unreasonable or excessive. Common obsessions in OCD include contamination from dirt, germs, viruses, body fluids and so on, fear of harm (for example, that door locks are not safe), excessive concern with order or symmetry, obsessions with the body or physical symptoms, religious, sacrilegious or blasphemous thoughts, sexual thoughts (for example, of being a paedophile or a homosexual), an urge to hoard useless or worn out possessions, or thoughts of violence or aggression (for example, stabbing one's baby) (Lochner & Stein, 2003).

Compulsions are repetitive behaviours or mental acts that the person feels driven to perform. A compulsion can either be overt and observable by others, or a covert mental act that cannot be observed. Covert compulsions are generally more difficult to resist or monitor than overt ones because they can be performed anywhere without others knowing and are easier to perform. Common compulsions include checking (for example, gas taps), cleaning, washing, repeating acts, mental compulsions (for example, repeating special words or prayers in a set manner), ordering, symmetry or exactness, hoarding/collecting and counting (Foa et al., 1995). The most frequent presentations are checking and cleaning, and these are the most easily recognised because they are on a continuum with everyday behaviour. A compulsion is not in itself pleasurable, which differentiates it from impulsive acts such as shopping or gambling, which are associated with immediate gratification.

Post-traumatic stress disorder

PTSD often develops in response to one or more traumatic events such as deliberate acts of interpersonal violence, severe accidents, disasters or military action. Those at risk of PTSD include survivors of war and torture, of accidents and disasters, and of violent crime (for example, physical and sexual assaults, sexual abuse, bombings and riots), refugees, women who have experienced traumatic childbirth, people diagnosed with a life-threatening illness, and members of the armed forces, police and other emergency personnel (Foa et al., 2008).

The most characteristic symptoms of PTSD are re-experiencing symptoms. People with PTSD involuntarily re-experience aspects of the traumatic event in a vivid and distressing way. Symptoms include flashbacks in which the person acts or feels as if the event is recurring; nightmares; and repetitive and distressing intrusive images or other sensory impressions from the event. Reminders of the traumatic event arouse intense distress and/or physiological reactions. As a result, hypervigilance for threat, exaggerated startle responses, irritability, difficulty in concentrating, sleep problems and avoidance of trauma reminders are other core symptoms. However, people with PTSD also describe symptoms of emotional numbing. These include inability to have any feelings, feeling detached from other people, giving up previously significant activities and amnesia for significant parts of the event.

Two further common mental health disorders, social anxiety disorder and specific phobias, are briefly described below. However, because no NICE guidelines currently exist for these disorders they will not be discussed in detail in the remainder of this chapter.

Social anxiety disorder

Social anxiety disorder, also referred to as social phobia, is characterised by an intense fear in social situations that results in considerable distress and in turn impacts on a person's ability to function effectively in aspects of their daily life. Central to the disorder is a fear of being judged by others and of being embarrassed or humiliated. This leads to the avoidance of a number of social situations and often impacts significantly on educational and vocational performance. The fears can be triggered by the actual or imagined scrutiny from others. The disorder often begins in early adolescence, and although an individual may recognise the problem as outside of normal experience, many do not seek help (Liebowitz et al., 1985).

Social anxiety disorder is characterised by a range of physical symptoms including excessive blushing, sweating, trembling, palpitations and nausea. Panic attacks are common, as is the development of depressive symptoms as the problem becomes chronic. Alcohol or drug misuse can develop because people use these substances in an attempt to cope with the disturbing and disabling symptoms. It is also often comorbid with other disorders such as depression (Kessler et al., 1999).

Specific phobias

A specific phobia is an unwarranted, extreme and persistent fear of a specific object or situation that is out of proportion to the actual danger or threat (Humphris et al., 1995). The fear and anxiety occur immediately upon encountering the feared object or situation and tend to lead to avoidance or extreme discomfort. The person with a specific phobia recognises that the fear is excessive, unwarranted or out of proportion to the actual risk. Specific phobias result in significant interference with the activities of daily life; they are usually grouped under a number of subtypes including animal, natural environment, blood-injection-injury and situational.

Gender

Depression and anxiety disorders tend to have a higher prevalence in women. Prevalence rates of depression have consistently been found to be between 1.5 and 2.5 times higher in women than men (Waraich et al., 2004). In the ONS survey (McManus et al., 2009) women were more likely than men to have a disorder (19.7 and 12.5%, respectively), with rates significantly higher for women across all categories of disorder except for panic disorder and OCD. The greatest difference between genders was among South Asian adults where the age-standardised rate among women (34.3% of South Asian women) was three times that of men (10.3% of South Asian men). Reasons cited in the 2007 ONS survey (McManus et al., 2009) include the impact of having children (Bebbington et al., 1991), exposure to domestic or sexual violence (Patel et al., 2006), adverse experiences in childhood and women's relative poverty (Patel et al., 1999; Piccinelli & Wilkinson, 2000).

Age

In the 2007 ONS survey (McManus et al., 2009) rates varied by age, with those aged 75 years and over least likely to have a disorder (6.3% of men and 12.2% of women). In women, the rate peaked among 45- to 54-year-olds of whom 25% met the criteria for at least one disorder. Among men, the rate was highest in 25- to 54-year-olds (14.6% of 25- to 34-year-olds, 15.0% of 35- to 44-year-olds and 14.5% of 45- to 54-year-olds).

Marital status

Women across all marital-status categories were more likely than their male counterparts to have disorders in the 2007 ONS survey (McManus et al., 2009), except for divorced people in whom the prevalence for men and women was very similar (26.6% for women and 27.7% for men). Among men, those currently divorced had the greatest likelihood of having a disorder, but variation by other marital status categories was less pronounced. For women the rate of disorder was high for divorced women, but even higher for separated women (33.0%). Men and women who were married or widowed had the lowest observed rates of disorder (10.1% of married men and 16.3% of married women; 10.4% widowed men and 17.4% widowed women).

Ethnicity

In the 2007 ONS survey (McManus et al., 2009), after age-standardisation of the data, there was little variation between white, black and South Asian men in the rates of any disorder. However, among women rates of all disorders (except phobias) were higher in the South Asian group. The number of South Asian women in the sample was small, so while the differences were pronounced they were only significant for disorders as a whole for GAD and panic disorder.

Socioeconomic factors

In the 2007 ONS survey (McManus et al., 2009), people living in households with the lowest levels of income were more likely to have a disorder than those living in the highest income households. A number of socioeconomic factors significantly affected prevalence rates in the 2000 ONS survey (Singleton et al., 2001): those with a depressive episode were more likely than those without a disorder to be unemployed, to belong to social classes 4 and below, to have no formal educational qualifications, to live in Local Authority or Housing Association accommodation, to have moved three or more times in the last 2 years and to live in an urban environment.

An illustration of the social origins of depression can be found in a general practice survey in which 7.2% (ranging 2.4 to 13.7%, depending upon the practice) of consecutive attendees had a depressive disorder. Neighbourhood social deprivation accounted for 48.3% of the variance among practices. Other variables were the proportion of the population having no or only one car and neighbourhood unemployment (Ostler et al., 2001). The evidence therefore overwhelmingly supports the view that the prevalence of common mental health disorders, however it is defined, varies according to gender and social and economic factors.

Learning disabilities

The rates of common mental health disorders in adults with learning disabilities are generally considered to be higher, but limited data and methodological problems (Smiley, 2005) mean that precise estimates are often not available and so uncertainty remains. In contrast, there is clearer evidence that other mental disorders such as problem behaviour have a higher rate of learning disabilities (Cooper et al., 2007). Rates of mental disorders may vary with the severity of the learning disability, being higher in more severe disability (Whitaker & Read, 2006), and challenges in assessment and diagnosis are considerable especially for those with more severe learning disabilities (Smiley, 2005; Whitaker & Read, 2006). However, some indication of the possible differential incidence of common mental health disorders can be obtained from the following studies. Richards and colleagues (2001) report a four-fold increase in the rates of affective disorders for people with mild learning disability. Rates of problems may also vary with the disorder; for example, Collacott (1999) reports a higher rate of depression in adults with Down's syndrome than in adults with other causes of learning disability. With regard to anxiety disorders, Cooper (1997) reports a rate of 2.5% for OCD in adults with a learning disability, which is higher than in the general adult population.

Depression

The average age of the first episode of major depression is the mid-20s and although the first episode may occur at any time, from early childhood through to old age, a substantial proportion of people have their first depressive episode in childhood or adolescence (Fava & Kendler, 2000).

Although depression has been understood to be a time-limited disorder lasting on average 4 to 6 months with complete recovery afterwards, it is now clear that incomplete recovery and relapse are common. The World Health Organization (WHO) study of mental disorders in 14 centres across the world found that 50% still had a diagnosis of depression 1 year later (Simon et al., 2002) and at least 10% of patients have persistent or chronic depression (Kessler et al., 2003). At least 50% of people following their first episode of major depression will go on to have at least one more episode (Kupfer, 1991), and after the second and third episodes the risk of further relapse rises to 70 and 90%, respectively (Kupfer, 1991). Early-onset depression (at or before 20 years of age) and depression occurring in old age have a significantly increased vulnerability to relapse (Giles et al., 1989; Mitchell & Subramaniam, 2005). Thus while the outlook for a first episode is good, the outlook for recurrent episodes over the long term can be poor with many patients experiencing symptoms of depression over many years (Akiskal, 1986).

Generalised anxiety disorder

Most clinical studies suggest that GAD is typically a chronic condition with low rates of remission over the short and medium term. Evaluation of prognosis is complicated by the frequent comorbidity with other anxiety disorders and depression, which worsen the long-term outcome and accompanying burden of disability (Tyrer & Baldwin, 2006). In the Harvard-Brown Anxiety Research Program, which recruited patients from Boston hospitals, the mean age of onset of GAD was 21 years, although many patients had been unwell since their teens. The average duration of illness in this group was about 20 years and despite treatment the outcome over the next 3 years was relatively poor, with only one in four patients showing symptomatic remission from GAD (Yonkers et al., 1996). The proportion of patients who became free from all psychiatric symptomatology was even smaller, at about one in six. In patients who remitted from GAD, the risk of relapse over the next year was about 15% increasing to about 30% in those who achieved only partial symptomatic remission (Yonkers et al., 1996).

The participants in the above study were recruited from hospital services and may not be representative of GAD in general. In a naturalistic study in the UK, Tyrer and colleagues (2004) followed up patients with anxiety and depression identified in psychiatric clinics in primary care and found that 12 years later 40% of those initially diagnosed with GAD had recovered, in the sense of no longer meeting criteria for any DSM-III psychiatric disorder. The remaining participants remained symptomatic, but only 3% still had GAD as the principal diagnosis; in the vast majority of patients, conditions such as dysthymia, major depression and agoraphobia were now more prominent. This study confirms the chronic and fluctuating symptomatic course of GAD in clinically-identified patients. It should be noted, however, that the majority of people with GAD in the community do not seek medical help for their symptoms (Wittchen & Jacobi, 2005) and the course of the illness in these circumstances is not established.

Panic disorder

Panic disorder comprises two main subtypes; panic disorder without agoraphobia and panic disorder with agoraphobia, with different presentations and often different courses. Panic disorder with agoraphobia (about one third of all presentations of panic disorder) is characterised by an avoidance of situations from which escape may not be possible or help not available in the event of a panic attack. Panic disorder with agoraphobia is also more common in women by a factor of approximately two to one. In contrast, panic disorder without agoraphobia is not situation-specific and symptoms may develop with no obvious or apparent cause (Weissman & Merikangas, 1986).

The most common age of onset is from the mid-teens to the mid-20s; however, onset may occur at any time. Panic disorder often begins with occasional panic attacks that increase in frequency and which in time lead to a pattern of a generalised avoidance. The course of this disorder often follows a chronic pathway for many people with panic disorder, with agoraphobia likely to have an even more chronic course (Francis et al., 2007).

Panic attacks commonly occur in many other disorders including specific phobias and social anxiety disorder, but they can also occur in GAD, drug or alcohol misuse, personality disorders and a number of physical disorders.

Obsessive-compulsive disorder

The mean age of onset of OCD is in late adolescence for men and early 20s for women, although age of onset covers a wide range of ages. However, it may take individuals between 10 and 15 years or longer to seek professional help. There is often comorbidity with a range of disorders, especially depression (for example, Abramowitz, 2004; Abramowitz et al., 2003; Apter et al., 2003), and other anxiety disorders (for example, Biederman et al., 2004; LaSalle et al., 2004; Nestadt et al., 2003; Welkowitz et al., 2000).

OCD may follow an acute, episodic or chronic course. In one of the largest follow-up studies, Skoog and Skoog (1999) conducted a 40-year prospective study and reported that approximately 60% of people with OCD displayed signs of general improvement within 10 years of illness, increasing to 80% by the end of the study. However, only 20% achieved full remission even after almost 50 years of illness; 60% continue to experience significant symptoms; 10% displayed no improvement; and 10% had deteriorated. A fifth of those who had displayed an early sustained improvement subsequently relapsed, even after 20 years without symptoms. This suggests that early recovery does not eliminate the possibility of very late relapse. Intermittent, episodic disorder was more common during the early stage of illness and predicted a more favourable outcome, whereas chronic illness predominated in later years. Worse outcome was predicted by early age of onset (particularly in males), experiencing obsessions and compulsions or magical thinking, poor social adjustment and early chronic course.

Post-traumatic stress disorder

The onset of symptoms in PTSD is usually in the first month after the traumatic event, but in a minority (less than 15%; McNally, 2003) there may be a delay of months or years before symptoms start to appear. PTSD also shows substantial natural recovery in the initial months and years after a traumatic event. Whereas a high proportion of trauma survivors will initially develop symptoms of PTSD, a substantial proportion of these individuals recover without treatment in the following years, with a steep decline in PTSD rates occurring in the first year (for example, Breslau et al., 1991; Kessler et al., 1995). On the other hand, at least one third of people who initially develop PTSD remain symptomatic for 3 years or longer and are at risk of secondary problems such as substance misuse (for example, Kessler et al., 1995). In the 2007 ONS (McManus et al., 2009) survey, screening positive for current PTSD declined with age, from 4.7% of 16- to 24-year-olds to 0.6% of adults aged 75 years or over.

Depression

Apart from the subjective suffering experienced by people who are depressed, the impact on social and occupational functioning, physical health and mortality is substantial. In fact, depressive illness causes a greater decrement in health state than major chronic physical illnesses such as angina, arthritis, asthma and diabetes (Moussavi et al., 2007).

Depression is a major cause of disability across the world. In 1990 it was the fourth most common cause of loss of disability-adjusted life years (DALYs) in the world and by 2020 it is projected to become the second most common cause (World Bank, 1993). In 1994 it was estimated that about 1.5 million DALYs were lost each year in the West as a result of depression (Murray et al., 1994). Depressive disorders account for 4.4% of the global disease burden or the equivalent of 65 million DALYs (Murray & Lopez, 1997; WHO, 2002).

Emotional, motivational and cognitive effects substantially reduce a person's ability to work effectively, with losses in personal and family income as well as lost contribution to society in tax revenues and employment skills. Wider social effects include: greater dependence upon welfare and benefits with loss of self-esteem and self-confidence; social impairments, including reduced ability to communicate and sustain relationships during the illness with knock-on effects after an episode; and longer-term impairment in social functioning, especially for those who have chronic or recurrent disorders. Some of the features of depression (such as lethargy) may impede access to appropriate healthcare.

Depression can also exacerbate the pain, distress and disability associated with physical health problems, and can adversely affect outcomes. Depression combined with chronic physical health problems incrementally worsens health compared with a physical health problem alone or even combinations of physical health problems (Moussavi et al., 2007). In addition, for a range of physical health problems findings suggest an increased risk of death when comorbid depression is present (Cassano & Fava, 2002). In coronary heart disease, for example, depressive disorders are associated with an 80% increased risk both for its development and of subsequent mortality in people with established disease, at least partly because of common contributory factors (Nicholson et al., 2006).

Suicide accounts for nearly 1% of all deaths and nearly two thirds are people with depression (Sartorius, 2001); putting it in another way, having depression leads to over a four-times higher risk of suicide compared with the general population, which rises to nearly 20 times in the most severely ill (Bostwick & Pankratz, 2000). Sometimes depression may also lead to acts of violence against others, and may even include homicide. Marital and family relationships are frequently negatively affected, and parental depression may lead to neglect of children and significant disturbances in children (Ramachandani & Stein, 2003).

Generalised anxiety disorder

Like major depression GAD is associated with a substantial burden of disability, equivalent to that of other chronic physical health problems such as arthritis and diabetes (Wittchen et al., 2002). There is evidence that comorbid depression and anxiety has a worse prognosis and more persistent symptoms than either depression or anxiety disorders alone (Kroenke et al., 2007). There is also evidence that, in the community, anxiety disorders are independently associated with several physical health problems and that this comorbidity is significantly associated with poor quality of life and disability (Sareen et al., 2006), and high associated health and social costs (Simon et al., 1995).

Studies have shown that the presence of GAD is also associated with significant impairments in occupational and social functioning. For example, over 30% of patients with GAD showed an annual reduction of work productivity of 10% or more compared with 8% of people with major depression. The figure for people with comorbid GAD and depression was over 45% (Wittchen et al., 2000). A large part of the economic cost of anxiety disorders is attributable to the costs of non-medical psychiatric treatment. Patients with GAD have increased numbers of visits not only to primary care doctors but also to hospital specialists, particularly gastroenterologists (Kennedy & Schwab, 1997; Wittchen et al., 2002). This may be a consequence of the distressing somatic symptoms that many people with GAD experience.

GAD also carries a considerable cost in personal suffering and difficulties. In the Harvard-Brown Program, one third of patients had never married and unemployment was higher than average (Yonkers et al., 1996). Suicidal ideation and suicide attempts are significantly increased in GAD, particularly in women, and this increase is still greater in the presence of comorbid major depression (Cougle et al., 2009).

Panic disorder

Panic disorder has considerable impact on the NHS, such as general practitioners (GPs), society as a whole (in terms of sickness and absence from work, labour turnover and reduced productivity), and individuals and families (Sherbourne et al., 1996). The impact in any of these spheres is difficult to measure accurately and there may be an underestimation of the impact, but it is still substantial. A person with panic disorder may experience severe and enduring physical sensations, which may lead them to think that they have a physical illness; it can be difficult for healthcare professionals to provide adequate reassurance that this is not the case, which may lead to multiple consultations. Their economic wellbeing may also be affected (Edlund & Swann, 1987).

Obsessive-compulsive disorder

OCD is ranked by the WHO in the top ten of the most disabling illnesses by lost income and decreased quality of life (Bobes et al., 2001). The severity of OCD differs markedly from one person to another. While some people may be able to hide their OCD from their own family, the disorder may have a major negative impact on social relationships leading to frequent family and marital discord or dissatisfaction, separation or divorce (Koran, 2000). It also interferes with leisure activities (Antony et al., 1998) and with a person's ability to study or work, leading to diminished educational and/or occupational attainment and unemployment (Koran, 2000; Leon et al., 1995). The social cost (that is the person's inability to fully function in society) has been estimated as US$5.9 billion in 1990, or 70.4% of the total economic cost of OCD (DuPont et al., 1995).

Post-traumatic stress disorder

Symptoms of PTSD cause considerable distress and can significantly interfere with social, educational and occupational functioning. It is not uncommon for people with PTSD to lose their jobs either because re-experiencing symptoms, as well as sleep and concentration problems, make regular work difficult or because they are unable to cope with reminders of the traumatic event they encounter while at work (Zatzick et al., 1997). The resulting financial problems are a common source of additional stress and may be a contributory factor leading to extreme hardship, such as home-lessness. The disorder has adverse effects on the person's social relationships, leading to social withdrawal. Problems in the family and break-up of significant relationships are not uncommon.

People with PTSD may also develop further, secondary psychological disorders as complications of the disorder. The most common complications are:

• the use of alcohol, drugs, caffeine or nicotine to cope with their symptoms, which may eventually lead to dependence
• depression, including the risk of suicide
• other anxiety disorders, such as panic disorder, which may lead to additional restrictions in their life (for example, inability to use public transport).

Other possible complications of PTSD include somatisation, chronic pain and poor health (Schnurr & Green, 2003). People with PTSD are at greater risk of physical health problems, including circulatory and musculoskeletal disorders, and have a greater number of medical conditions than those without PTSD (Ouimette et al., 2004).

The course and prognosis of all common mental disorders are affected by a range of social factors, a number of which have been already discussed above. However, a range of factors related to social exclusion have a specific effect on access to services. This means that a number of groups may have particular problems accessing services including: those involved with the criminal justice system; homeless or precariously housed people; travelling communities; some groups of younger people (including those who have been in care as children and adolescence); people who misuse drugs and alcohol; and those of uncertain immigration status.

Costs of depression

Depression is associated with high prevalence and treatment costs, and as stated above is considered one of the most important risk factors for suicide (Knapp & Illson, 2002). Furthermore, depression has a large impact on workplace productivity. As a result, depression places an enormous burden on both the healthcare system and the broader society.

Depression has a major financial impact on health and social services and the wider economy. A review was conducted by the King's Fund in 2006 to estimate mental health expenditure including depression in England for the next 20 years, to 2026 (McCrone et al., 2008). The study estimated the total cost of services for depression in England in 2007 to be £1.7 billion, while lost employment increased this total to £7.5 billion. Based on the estimate that 1.45 million people would have depression in 2026, the authors estimated that the total service cost would be £12.2 billion when accounting for prescribed drugs, inpatient care, other NHS services, supported accommodation, social services and lost employment in terms of workplace absenteeism.

One of the key findings from the cost-of-illness literature is that the indirect costs of depression far outweigh the health service costs. A study by Thomas and Morris (2003) suggested that the effect on lost employment and productivity was 23 times larger than the costs falling to the health service. Other studies have also supported these findings. Based on UK labour-market survey data, Almond and Healey (2003) estimated that respondents with self-reported depression/anxiety were three times more likely to be absent from work (equivalent to 15 days per year) than workers without depression/anxiety. Furthermore, a US-based study suggests that depression is a major cause of reduced productivity at work, in terms of ‘work cut-back days’ (Kessler et al., 2001). This reduced workplace productivity is unlikely to be adequately measured by absenteeism rates and further emphasises the ‘hidden costs’ of depression (Knapp, 2003). A recent study conducted by the the Centre for Economic Performance's Mental Health Policy Group estimated that the total loss of output (in terms of lost productivity, absenteeism from work or benefits received) due to depression and chronic anxiety is some £12 billion per year (Layard, 2006).

Other intangible costs of illness include the impact on the quality of life of people with depression and their families and carers. Certainly, the cost-of-illness calculations presented here and in Table 2 show that depression imposes a significant burden on individuals and their families and carers, the healthcare system and the broader economy through lost productivity and workplace absenteeism. Furthermore, it is anticipated that these costs will continue to rise significantly in future years. Therefore, it is important that the efficient use of available healthcare resources is used to maximise health benefits for people with depression.

Table 2

Summary of cost of illness data for depression and anxiety.

Costs of anxiety disorders

Anxiety disorders place a significant burden on individuals as well as on the healthcare system. Although direct comparisons between studies are difficult to make due to variations in country, health services and year of interest, economic cost has been estimated at over US$40 billion (Andlin-Sobocki et al., 2005; see Table 2 for further information). Estimated costs are incurred by healthcare resource utilisation such as mental health services, medication, hospitalisation, nursing homes and outpatient visits, productivity losses and, to a lesser extent, by provision of other services such as criminal justice services, social welfare administration and incarceration, as well as family care-giving (0.8%) (Andlin-Sobocki et al., 2005).

Total healthcare cost is not the only important outcome to consider when investigating cost. Marciniak and colleagues (2005) found that the total medical cost per person with any anxiety disorder was estimated at US$6,475 in 1999. More specifically, when looking at GAD alone, the figure increased to US$2,138 when controlling for demographics and other disease states. This increased cost may be due to factors such as increased outpatient mental health service use or medical specialist service use. Furthermore, people with anxiety tend to miss more days of work or have a short-term disability than controls (Marciniak et al., 2004).

Anxiety disorders are associated with a wide range of comorbidities, which result in a substantial increase in the total healthcare costs. Souêtre and colleagues (1994) estimated the total direct and indirect costs incurred by people with GAD with and without comorbidities using data on 999 people participating in a French cross-sectional study. Controlling for confounding variables, the prevalence of healthcare utilisation in terms of hospitalisation, laboratory tests and medications, and the respective medical costs were found to be significantly higher in people with GAD and other comorbidities than those without comorbidities. Moreover, comorbidities were associated with increased absenteeism from work. In particular, comorbid depression (Marciniak et al., 2005; Wetherell et al., 2007; Zhu et al., 2009) and physical pain (Olfson & Gameroff, 2007; Zhu et al., 2009) have been found to have a significant impact on treatment costs incurred by people with GAD.

Costs of post-traumatic stress disorder

In 2003 to 2004, social and welfare costs of claims for incapacitation and severe disablement from severe stress and PTSD amounted to £103 million, which is £55 million more than was claimed 5 years previously (Hansard, 2004). Therefore, PTSD presents an enormous economic burden on families, the national health services and society as a whole.

Depression

There is a wide range of antidepressant drugs available for people with depression. These can be grouped into tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors and a range of other chemically unrelated antidepressants (British National Formulary [BNF] 59; British Medical Association & the Royal Pharmaceutical Society of Great Britain, 2010).

Generalised anxiety disorder

Placebo-controlled trials indicate that a wide range of drugs with differing pharmacological properties can be effective in the treatment of GAD (Baldwin et al., 2005). In recent years, antidepressant medications such as SSRIs have been increasingly used to treat GAD (Baldwin et al., 2005).

Conventional antipsychotic drugs and the newer ‘atypical’ antipsychotic agents have also been used in the treatment in GAD, both as a sole therapy and as an ‘addon’ to SSRI therapy when the latter has proved ineffective (Pies, 2009). However, the greater side-effect burden of antipsychotic drugs means that presently their use is restricted to people with refractory conditions, with prescribing being guided by secondary care physicians.

Panic disorder

There is evidence to support the use of pharmacological intervention in the treatment of panic disorder, in particular with SSRIs. When a person has not responded to an SSRI, other related antidepressants may be of benefit. There is little good evidence to support the use of benzodiazepines. In contrast to a number of other depressive and anxiety disorders, there is little evidence to support the use of pharmacological and psychological interventions in combination.

Obsessive-compulsive disorder

Pharmacological investigations have demonstrated effectiveness in OCD, in particular with SSRIs and related antidepressants (Montgomery et al., 2001; Zohar & Judge, 1996) for moderate to severe presentations, especially if the problem has a chronic course; this may be in combination with psychological interventions.

Post-traumatic stress disorder

At present there is no conclusive evidence that any drug treatment helps as an early intervention for the treatment of PTSD-specific symptoms (NCCMH, 2005). However, for people who are acutely distressed and may be experiencing severe sleep problems, consideration may be given to the use of medication. Drug treatments for PTSD should not be used as a routine first-line treatment for adults (in general use or by specialist mental health professionals) in preference to a trauma-focused psychological therapy. Drug treatments should be considered for the treatment of PTSD in adults when a person with the disorder expresses a preference not to engage in a trauma-focused psychological treatment. The SSRI paroxetine is the only drug with a current UK product licence for PTSD.

Depression

Effective psychological treatments for depression identified in the NICE Depression guideline (NICE, 2009a) include: cognitive behavioural therapy (CBT), behavioural activation, interpersonal therapy (IPT), behavioural couples therapy and mindfulness-based cognitive therapy. For moderate to severe disorders these are often provided in conjunction with antidepressants. For subthreshold and milder disorders, structured group physical activity programmes, facilitated self-help and CCBT are effective interventions.

Generalised anxiety disorder

Cognitive and behavioural approaches are the treatments of choice for GAD. People who have moderate to severe disorder, particularly if the problem is long-standing, should be offered CBT or applied relaxation. For those with milder and more recent onset disorders, two options are available: facilitated or non-facilitated self-help based on CBT principles and psychoeducational groups also based on CBT principles.

Panic disorder

Cognitive and behavioural approaches are again the treatments of choice for panic disorder. People who have a moderate to severe GAD, particularly if it is longstanding, should receive between 7 and 14 hours of therapist-provided treatment over a 4-month period. For those with milder and more recent onset GAD, facilitated or non-facilitated self-help based on CBT principle are efficacious treatments.

Obsessive-compulsive disorder

CBT is the most widely used psychological treatment for OCD in adults (Roth & Fonagy, 2004). The main CBT interventions that have been used in the treatment of OCD are exposure and response prevention (ERP) (for example, Foa & Kozak, 1996; Marks, 1997), different variants of cognitive therapy (Clark, 2004; Freeston et al., 1996; Frost & Steketee, 1999; Krochmalik et al., 2001; Rachman, 1998, 2002 and 2004; Salkovskis et al., 1999; van Oppen & Arntz, 1994; Wells, 2000), and a combination of ERP and cognitive therapy (see Kobak et al., 1998; Roth & Fonagy, 2004). ERP and cognitive therapy have different theoretical underpinnings, but may be used together in a coherent package.

Post-traumatic stress disorder

General practical and social support and guidance about the immediate distress and likely course of symptoms should be given to anyone following a traumatic incident. Trauma-focused psychological treatments are effective for the treatment of PTSD, either trauma-focused CBT or eye movement desensitisation and reprocessing (EMDR). These treatments are normally provided on an individual outpatient basis and are effective even when considerable time has elapsed since the traumatic event(s).

Use of healthcare services

Of the people reporting a common mental health disorder in the ONS survey (McManus et al., 2009), 39% had used some type of healthcare service for a mental or emotional problem within the last year, compared with 6% of men and women without a disorder.

Primary care services

General practice services were the most common healthcare service used in the ONS survey. A total of 38% of people with a common mental health disorder contacted their GP for help. Depression and phobias were associated with the highest use of healthcare services for a mental or emotional problem (both 67%), and mixed anxiety and depression was associated with the lowest use (30%) (McManus et al., 2009).

Community care services

All respondents in the ONS survey (McManus et al., 2009), were asked about community and day care services used in the past year. Community and day care services were used less than healthcare services. Those with phobias made most use of community or day care services (49%), while mixed anxiety and depressive disorder was associated with the lowest rate of community or day care service use (12%).

Summary

In summary, common mental health disorders are associated with a range of symptoms that can lead to significant impairment and disability, and high costs both for the individual with the disorder and for society as a whole.

Effective treatments are available that differ depending on the disorder. As a result, early detection, assessment and intervention are key priorities for any healthcare system. This guideline, which is focused on primary care, will provide recommendations on how to best identify and assess common mental health disorders and the key indicators for treatment in order to help improve and facilitate access to care, and the route through care.

Presentation of people with a common mental health disorder to primary care

Of the 130 cases of depression (including mild cases) per 1000 population, only 80 will consult their GP. The stigma associated with mental health problems generally (Sartorius, 2002), and the public view that others might view a person with depression as unbalanced, neurotic and irritating (Priest et al., 1996), may partly account for the reluctance of depressed people to seek help (Bridges & Goldberg, 1987). The most common reasons given for reluctance to contact the family doctor include: did not think anyone could help (28%); a problem one should be able to cope with (28%); did not think it was necessary to contact a doctor (17%); thought problem would get better by itself (15%); too embarrassed to discuss it with anyone (13%); and afraid of the consequences (for example treatment, tests, hospitalisation or being sectioned under the Mental Health Act; 10%) (Meltzer et al., 2000).

Most anxiety disorders are found more frequently in primary care than in the community except for social anxiety disorder and agoraphobia, both of which involve avoidance of public places such as doctors' surgeries (Bushnell et al., 2005; Oakley Browne et al., 2006; see Table 3). However, even when people with anxiety and depression do consult their GP, their disorder often goes unrecognised, partly because many do not present their psychological symptoms overtly.

Table 3

Twelve-month prevalence of anxiety disorders in New Zealand (Oakley Browne et al., 2006).

Dowrick and colleagues (2010) carried out systematic reviews to identify groups for whom there are particular problems accessing mental health services, and to identify systems for promoting access. Poorer access to care has been found to be associated with lower social class, geographical location, ethnic minority groups, the presence of sensory or other impairments, the presence of learning difficulties, and particular demographic factors including age and gender (for example, older people or younger men).

This guideline seeks to identify service developments or changes that may be specifically designed to promote access, both for the general population and for specific outreach groups (see Chapter 4). Particular areas include: community outreach; providing education and information concerning the nature of mental disorder; and new and adapted models of service delivery, which focus on the needs of black and minority ethnic (BME) groups and older people.

Recognition of depression

Of the 80 people with depression per 1000 population who do consult their GP, 49 are not recognised as depressed, mainly because most such patients are consulting for a somatic symptom and do not consider themselves mentally unwell despite the presence of symptoms of depression (Kisely et al., 1995). People who present with somatic symptoms are especially unlikely to be recognised (Kisely et al., 1995). GPs tend to be better at recognising more severe forms of the disorder (Goldberg et al., 1998; Thompson et al., 2001). With 50% of people with depression never consulting a doctor, 95% never entering secondary mental health services, and many more having their depression going unrecognised and untreated, this is clearly a problem for primary care.

Recognition of anxiety disorders

Anxiety symptoms are also often not recognised by primary healthcare professionals because, once again, patients may not complain of them overtly (Tylee & Walters, 2007). Cases of anxiety are especially likely to be missed when people frequently attend with multiple symptoms, despite reassurance. Instead, these symptoms are often characterised as possible symptoms of cardiovascular, respiratory, gastrointestinal, neurological or musculoskeletal disease (Blashki et al., 2007).

For many people with a common mental health disorder, stigma and avoidance may contribute to under-recognition of their condition. Pessimism about possible treatment outcomes may further contribute to this. However, GPs themselves can contribute to the under-recognition of these conditions.

Consultation skills

GPs are immensely variable in their ability to recognise depressive illnesses, with some recognising virtually all of the patients found to be depressed at independent research interview, and others recognising very few (Goldberg & Huxley, 1992; Üstün & Sartorius, 1995).

The communication skills of the GP make a vital contribution to determining their ability to detect emotional distress, and those with superior skills allow their patients to show more evidence of distress during their interviews thus facilitating detection (Goldberg & Bridges, 1988; Goldberg et al., 1993).

According to Goldberg and colleagues (1980a and 1980b), ten behaviours are associated with greater detection. These include factors such as making eye contact, having good interview skills, asking well-formulated questions and focusing on more than just a symptom count. Attempts to improve GP behaviour have been successful (Ostler et al., 2001; Tiemens et al., 1999), although results are mixed (Kendrick et al., 2001; Thompson et al., 2000) and interventions sometimes fail to impact on patient outcomes despite changes in clinician behaviour (Gask et al., 2004).

Case identification

The fact that common mental health disorders often go undiagnosed among primary care attenders has led to suggestions that clinicians should systematically screen for hidden disorders. However, general screening is not without its problems and is currently not recommended in most countries, including the UK. Instead, targeted case identification, which involves screening a smaller group of people known to be at higher risk based on the presence of particular risk factors, may be a more useful method of improving recognition of psychological disorders in primary care.

Whooley and colleagues (1997) found that two questions were particularly sensitive in identifying depression:

• During the last month, have you often been bothered by feeling down, depressed or hopeless?
• During the last month, have you often been bothered by having little interest or pleasure in doing things?

The current NICE Depression guideline (NICE, 2009a) recommends that GPs be alert to possible depression in at-risk patients and consider asking the above Whooley questions when depression is suspected. If the person screens positive, further follow-up assessments should then be considered. Currently, no equivalent Whooley questions have been recommended for anxiety.

The view of the GDG for this guideline was that the development of separate case identification questions for each type of anxiety disorder would very likely be impractical and have no utility for routine use in primary care. The preference was to explore the possibility of a small number of case identification questions with general applicability for a range of anxiety disorders. A potentially positive response would then prompt a further assessment. This is dealt with in Chapter 5.

Stepped care

Currently, much of the UK mental health system is organised around the principles of stepped care. Stepped care (Scogin et al., 2003) is a framework that is increasingly being used in the UK to provide a structure for best-practice clinical pathways to care. It is designed to increase the efficiency of service provision with an overall benefit to patient populations. The basic principle is that patients presenting with a common mental health disorder will ‘step through’ progressive levels of treatment as necessary, with the expectation that many of these patients will recover during the less intensive phases. High-intensity treatments are reserved for patients who do not benefit from low-intensity treatments, or for those who can be accurately predicted not to benefit from such treatments. Thus, stepped care has the potential for deriving the greatest benefit from available therapeutic resources (Bower & Gilbody, 2005) and has been recommended in a number of NICE guidelines including Depression (NICE, 2009a) and Generalised Anxiety Disorder and Panic Disorder (With or Without Agoraphobia) in Adults (NICE, 2011a).

A potential disadvantage of a stepped-care approach is that patients who do not benefit from low-intensity treatments may still have to undergo such treatments before a successful outcome is achieved. To maximise the efficiency of care delivery, patients who can be predicted as unlikely to respond to less intensive treatments ideally should be referred straight to higher levels; that is, care should be ‘stratified’ to an extent (Bower et al., 2006). However, prognostic evidence to support such decisions is currently lacking.

Improving Access to Psychological Therapies programme

In 2004 the economist Richard Layard made the case for a major expansion in the availability of psychological treatments, which he suggested could bring a significant reduction in the welfare benefits bill and increased tax contributions of those helped back to work. In 2006 the government established the Improving Access to Psychological Therapies (IAPT) programme, based heavily on the stepped-care approach. Clark and colleagues (2009) reported on the initial success of two demonstration sites in Newham and Doncaster, and the IAPT programme proposes a phased national roll-out by 2013 (to date, over 50% of Primary Care Trusts have an IAPT service). Self-referral to IAPT services is also actively encouraged, with emerging evidence to suggest that it increases access for vulnerable groups, such as BME groups to psychological interventions (Clark et al., 2009). In addition, an analysis of the first full year of operation of the first wave of roll-out sites (October 2008 to September 2009) has recently been published (Glover et al., 2010). Anonymous patient-level data were collected from 32 sites with the aim of evaluating whether the ‘commitments relating to accessibility, the provision of NICE-approved therapies and detailed outcome monitoring were progressing appropriately’. The authors concluded that the large amount of outcome data collected is a remarkable achievement, although there are some limitations and shortcomings that need to be addressed. For example, the analysis suggests that the diagnostic coding frame needs to be extended to include panic disorder and more research needs to be conducted to establish how reliable diagnoses can be obtained. Furthermore, in terms of equality of access, the authors state that ‘older people and men appeared under-represented in relation to expectation based on the patterns of morbidity shown by the psychiatric morbidity survey. The position for people with disabilities is not recorded at all in most sites, making it difficult to see how commissioners and providers can discharge their responsibilities to promote access to services for disabled people under disability discrimination legislation.’ Also, ‘after allowing for all other relevant factors for which data were available, Black people were significantly less likely to receive any treatment or to recover on either the two-scale or the three-scale makers, Asians were less likely to receive high intensity treatment (CBT or counselling), and both were significantly less likely to receive CBT’. More generally, with regard to treatment received, there was evidence to suggest that more needs to be done to ensure that the treatment given for specific diagnoses is aligned to that recommended in NICE guidelines.