What is the prevalence of depression?
- Worldwide estimates of lifetime prevalence : 4 and 10% for depression .
- The estimated point prevalence for a depressive episode in the UK in 2000 was 2.6% (males 2.3%, females 2.8%).
- If mixed depression and anxiety was included, these figures rose dramatically to 11.4% (males 9.1%, females 13.6%) .
- Prevalence rates are 1.5 and 2.5 times higher in women than men
- Those with a depressive episode were more likely than others to be unemployed, to belong to social classes 4 and below, to have lower predicted intellectual function, to have no formal educational qualifications .
- No significant effect of ethnic status on prevalence rates
Women are more susceptible to depression, regardless of culture.
What are the economic costs of depression?
- by 2020, depression is projected to become the second leading cause of disability and account for 4.4% of the global disease burden, (WHO)
- King’s Fund in 2006 to estimate mental health expenditure, including depression, in England for the next 20 years,(McCrone et al., 2008). It was estimated that there were 1.24 million people with depression in England, and this was projected to rise by 17% to 1.45 million by 2026 .
- Overall, the total cost of services for depression in England in 2007 was estimated to be £1.7 billion, while lost employment increased this total to £7.5 billion. By 2026, these figures were projected to be £3 billion and £12.2 billion, respectively
The second greatest burden on economic costs from disease.
When does depression become a mental disorder?
- Establishing a valid diagnostic boundary between depressive illness versus intense normal sadness or mild adjustment disorder that generally does not require intervention has proven challenging.
- The problem is that non-pathological reactions to major losses and stressors possess many of the same general-distress symptoms as depressive disorder.
Mario Maj - how can we differentiate a depressive disorder from ‘normal’ sadness?
• The qualitative approach
This approach, endorsed by several European psychopathologists, assumes that there is always a qualitative difference between ‘true’ depression and ‘normal’ sadness.
• The contextual approach
This approach argues that depression, contrary to normal sadness, is either unrelated to a life event or disproportionate to the preceding event in intensity, duration and degree of the functional impairment it produces
• The pragmatic approach
This approach assumes that, since there is a range of severity from ordinary sadness to clinical depression, the boundary has to be fixed on pragmatic grounds (i.e. giving priority to clinical utility). This is what the DSM-IV and ICD 10 actually tries to achieve, regarding depression as a ‘disorder’ when it reaches a given threshold in terms of severity, duration and degree
Mario Maj: President of World Psychiatric Association (2008-2011)
Article - see slides
Third approach was beneficial and found evidence for that - pragmatic approach
Cluster of symptoms - when have those together, it is an illness: diagnostic threshold
Describing the prognosis is important in diagnosis.
The pragmatic approach
• Of the three approaches , the first two, which are not supported by currently available research evidence, whereas the third has some empirical support.
• An analogy seems to emerge between depression and common physical diseases such as hypertension and diabetes, which also occur a long a curve , with at least two identifiable thresholds: one for a condition deserving clinical attention and another for a state requiring pharmacological treatment.
• Diagnostic threshold ( symptoms cluster ) or ( Diagnostic Criteria )
Classification of mood disorders…
- In between 1950 and 1960 , psychiatrists on both sides of the Atlantic noticed increasing difficulty in communicating their understanding of clinical depression . Depression’ is an unsatisfactory term; it is too vague and has too many meanings No common language or clear diagnostic criteria
- .The clinical practice depends on the individual clinical education and expertise.
- Diseases can be classified byaetiology (cause),pathogenesis (mechaism), or bysymptom(s).
- Cassidy et al. outlined diagnostic criteria of depression as follows: “the patient (a) had made at least one statement of mood change … and (b) had any 6 of the 10 following special symptoms: slow thinking, poor appetite, constipation, insomnia, feels tired, loss of concentration, suicidal ideas, weight loss, decreased sex interest, and wringing hands, pacing, over-talkativeness, or press of complaints.”
- Charney then located Cassidy, who was retired and living in Florida. When asked how he decided on the threshold of six out of 10 criteria, Cassidy replied, “It sounded about right.”
- Feighner and colleagues’ “Diagnostic Criteria for Use in Psychiatric Research,” which proposed criteria for 14 psychiatric disorders, was published in January 1972 (1) in theArchives of General Psychiatry.
Development of operational definition of depression…
- Feighner and colleagues developed systematic descriptions of symptoms that did not rely upon theoretical assumptions or interpretations.
- These criteria were incorporated in the International Diseases Classification was the UK Glossary of Mental Disorders for ICD-8 (1967)
- ICD-8 contained the following mood disorders ; Manic-depressive psychosis, depressed type Involutional melancholia Reactive depressive psychosis Depressive neurosis .
- ICD-8 followed by the ICD-9, then by the ICD-10
- These diagnostic criteria have been Validated in different studies
What is the ICD-10 definition of a depressive episode?
1-Depressed Mood
2-Marked loss of interest or pleasure
3-Decreased energy or fatigability
• (a)reduced concentration and attention;
• (b)reduced self-esteem and self-confidence;
• (c)ideas of guilt and unworthiness (even in a mild type of episode);
• (d)bleak and pessimistic views of the future;
• (e)ideas or acts of self-harm or suicide;
• (f)disturbed sleep
• (g)diminished appetite.
Duration 2 weeks
Sustained everyday for 2 weeks
What are the difference severity levels of depressive episodes and recurrences?
- Mild ; one of the first 3 symptoms + total of 4 symptoms
- Moderate ; two of the first 3 symptoms + total five symptoms
- Sever ; all of the first 3 symptoms + total eight symptoms
- Recurrent Depressive Disorder ;at least more than one episode lasted for more than 2 weeks
- Persistent Mood Disorders ; duration for 2 years +insufficient symptoms to meet the criteria of depressive episode
About melancholic and psychotic depression
- Some patients have a more severe and typical presentation, including morning worsening ,complete lack of reactivity of mood , weight loss, reduced sleep with a waking early in the morning . It is referred to as depressive episode with somatic symptoms in ICD–10.
- People with severe depression may also develop psychotic symptoms (hallucinations and/or delusions), most commonly thematically consistent with the negative, self-blaming cognitions , others may develop psychotic symptoms unrelated to mood (Andrews & Jenkins, 1999).
What are the problems with the diagnostic criteria system of depression?
- The symptom criteria of MDD are broadly defined and include reversed conditions. For example, a change in appetite either increase or decrease ; sleep problems either , decrease or increase
- The diagnosis can be made using different combination of symptoms
- A recent study identified 1030 unique depression symptom profiles in 3703 individuals diagnosed with MD, translating into only 3.6 patients per profile (Fried and Nesse, 2015).
- Symptoms of depression overlap with the symptoms of other psychiatric disorders like anxiety and even with the symptoms of physical health problems
- All symptoms are equally good severity indicators.
- Studies showed that specific depressive symptoms like sad mood, insomnia, concentration problems, and suicidal ideation are distinct phenomena that differ from each other in underlying biology, impact on impairment.
- Jang et al. showed that 14 depression symptoms differ from each other in their degree of heritability
- Another study , revealed differential associations of symptoms with specific genetic polymorphisms; for example, the symptom ‘middle insomnia’ assessed by the HRSD was correlated with the GGCCGGGC haplotype in the first haplotype block ofTPH1.
- Furthermore, biomarker differ for different somatic symptoms such as sleep problems, appetite gain, and weight gain seem elevated in the context of inflammation .
Relying on patients giving accurate information - not hard evidence
Some of the things are on a continuum - no distinctive point at which it is classifiable.
Different combinations lead to same diagnosis, even though the different combinations can have totally different effects.
What are the NICE guidelines depression diagnosis?
NICE GUIDELINE
1-Identification of major depression is based not only on its severity but also on persistence, the presence of other symptoms, and the degree of functional and social impairment. The greater the severity of depression, the greater the morbidity and adverse consequences (Lewinsohn et al., 2000; Kessing, 2007).
2-Commonly, depressive illness is unreactive to circumstance, remaining low throughout the course of each day. For some of the patients, mood may be reactive to positive experiences although these elevations in mood are not sustained, with depressive feelings re-emerging, often quickly (Andrews & Jenkins, 1999)
What are the nice guidelines on sub-threshold depression?
• In recent years there has been a greater recognition of the need to consider depression that is ‘subthreshold’; that is, where the depression does not meet the full criteria for a depressive/major depressive episode.(Rowe & Rapaport, 2006)
• The following definitions of depression are used in the guideline update:
● Sub threshold depressive symptoms: fewer than five symptoms of depression
People that have some of the symptoms but not enough of them, these people shouldn’t be ignored. This is a problem.
Has recently been recognised by Nice Guidelines and has been given definition of sub threshold depression
Sub threshold depression
- persons falling below the threshold are not recognized in primary care settings or community surveys and often not included in biological (imaging and genetic)
- Medline search of the literature published between January 2001 and September 2011 was conducted
- Prevalence rates for subthreshold depression ranged from 2.9% to 9.9% in primary care and from 1.4% to 17.2% in community settings
What are screening and assessment tools for depression?
- NICE recommends that any patient who may have depression should be asked the following two questions
- During the last month have you been feeling down, depressed or hopeless?
- During the last month have you often been bothered by having little interest or pleasure in doing things?
- Assessing newly diagnosed patients:
- Patient Health Questionnaire (PHQ-9): this is a nine-item questionnaire which helps both to diagnose depression and to assess severity. It is based directly on the diagnostic criteria for major depressive disorder in the Diagnostic and Statistical Manual - Fourth Edition (DSM-IV.
- Hospital Anxiety and Depression (HAD) Scale:
- Beck Depression Inventory® - Second Edition (BDI-II): this also uses DSM criteria. it takes about five minutes to complete. It is an assessment of the severity of depression and is graded as minimal (0-13), mild (14-19), moderate (20-28) and severe (29-36). It consists of 21 items to assess the intensity of depression in clinical and normal patients. Each item is a list of four statements arranged in increasing severity about a particular symptom of depression. It is also not free but can be purchased from the supplier’s website
How are symptoms of depression related to each other?
The analysed 27 items of the Inventory of Depressive Symptomatology, which was administered in the Netherlands Study of Depression and Anxiety
• The focus was on nodes: node strength, betweenness, and clustering coefficient .
• Node strength is a measure of the number of connections a node has,
• Betweenness measures how often a node lies on the shortest path between nodes
• The local clustering coefficient is a measure of the degree to which nodes tend to cluster together
• These measures are indicative of the potentialspreading of activitythrough the network. As activated symptoms can activate other symptoms, a more densely connected network facilitates symptom activation.
What is the impact of individual depressive symptoms on impairment of psychosocial functioning?
Fried EI, Nesse RM, Gong Q, ed. PLoS ONE. 2014
- Data from 3,703 depressed outpatients in the first treatment stage of the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study.
- Participants reported on the severity of 14 depressive symptoms, and stated to what degree their depression impaired psychosocial functioning (in general, and in the five domains work, home management, social activities, private activities, and close relationships).
- We tested whether symptoms differed in their associations with impairment.
- results show that symptoms varied substantially in their associations with impairment
- Furthermore, symptoms had significantly different impacts on the five impairment domains. Overall, sad mood and concentration problems had the highest unique associations with impairment and were among the most debilitating symptoms in all five domains.
Sad mood always present
About understanding how these symptoms can affect your functioning and what role that symptoms plays in the overall picture of depression.
What is the differential diagnosis leading to depression?
- Bipolar Disorders
- Anxiety
- Obsessive-compulsive disorder
- Panic disorder
- Phobic disorders
- Posttraumatic stress disorder
- personality disorders
- Physical health problems
- Central nervous system diseases (eg, Parkinson disease, dementia, multiple sclerosis, neoplastic lesions)
- Endocrine disorders (eg, hyperthyroidism, hypothyroidism)
- Drug-related conditions (eg, cocaine abuse, side effects of some CNS depressants)
- Infectious disease (eg, mononucleosis)
- Sleep-related disorders
What is the genetic cause of depression?
- A recent review of twin studies in MDD-RU estimated heritability at 37%.
- Family studies ; There was a twofold to fourfold increased risk of MDD-RU among the first-degree relatives of MDD-RU
- linkage studies in MDD have suggested several regions in the genome that might harbour risk alleles, findings have been inconsistent, and thus far, no established universal genetic risk factor or causative gene for depression has been identified.
What are the recent findings of the genetic determinants of depression and future directions?
Some of the most commonly studied candidate genes have been those regulating serotonin (5-HT) and dopamine (DA) neurotransmission.
Unfortunately, most candidate gene studies have been underpowered and replication of findings has been rare.
More recently, the availability of DNA microarrays have enabled genome wide association studies (GWAS) that do not rely on prior hypotheses. The GWAS approach allows for the analysis of a million or more variants across the entire genome. The ultimate goal of these genetic association studies is to improve diagnosis, prevention, and treatment through a nuanced understanding of the genetic underpinnings of the disease.
About childhood trauma and its relation to chronic depression in adulthood
- The aim of this study was to examine
- 75.6% of the chronically depressed patients reported clinically significant histories of childhood trauma.
- 37% of the chronically depressed patients reported multiple childhood traumatization.
- Experiences of multiple trauma also led to significantly more severe depressive symptoms.
- Stepwise multiple regression analysis suggested that childhood emotional abuse and sexual abuse were significantly associated with a higher symptom severity in chronically depressed adults.
What is the role of stress in depression?
- In community samples, up to 70-80% of Major Depressive Episodes (MDEs) are preceded by major life events, particularly in the 1-3 months before MDE onset, and it has been estimated that stressors are approximately 2.5 times more frequent in the period before an MDE relative to a comparable period in controls (Hammen 2005;Mazure 1998).
- In addition, chronic stressors have been linked to poorer prognosis and more frequent relapse (e.g.Lethbridge & Allen 2008),
- (1) lack of control, (2) inability to escape or resolve the aversive situation (e.g., entrapment), or (3) loss of status (e.g., humiliation) appear to be particularly depressogenic (e.g.,Brown & Harris 1978;Kendler et al. 2003). Findings emphasizing the uncontrollability component of stressors are consistent with data indicating that perceived control over stressors is a key modulator of physiological stress responses (Dickerson & Kemeny 2004).
- stressors play a stronger role in triggering first episodes of depression than recurrences (e.g.,Daley et al. 2000), and the association between stressors and depression becomes weaker with increasing number of episodes (Kendler et al. 2000).
What are some psychological theories of depression?
- One major cognitive theorist isAaron Beck.
- Beck (1967) identified three mechanisms that he thought were responsible for depression:
- The cognitive triad (of negative automatic thinking)
- Negative self schemas
- Errors in Logic (i.e. faulty information processing)
- Freud (1917) prosed that some cases of depression could be linked to loss or rejection by a parent. Depression is like grief, in that it often occurs as a reaction to the loss of an important relationship
- Freuddistinguished between actual losses (e.g. death of a loved one) and symbolic losses (e.g. loss of a job). Both kinds of losses can produce depression
- Later, Freud modified his theory stating that the tendency to internalize loss objects is normal, and that depression is simply due to an excessively severe super-ego demands
- Martin Seligman (1974) proposed a cognitive explanation of depression called learned helplessness
What is the neurobiological hypothesis of depression?
Monoamine hypothesis Serotonin–norepinephrine
• Depression can be improved by agents that increase synaptic concentrations of monoamines. . However, the pathophysiology of depression itself remains unknown. Still, the monoamine hypothesis does not address key issues such as why antidepressants are also effective in other disorders such as panic disorder, obsessive-compulsive disorder, and bulimia, or why all drugs that enhance serotonergic or noradrenergic transmission are not necessarily effective in depression.
The role of corticotropin-releasing factor in determining sensitivity to stress
• Stress may activate the hypothalamus and therefore may activate the hypothalamic–pituitary–adrenal axis directly, Activation of this system is thought to increase vigilance and fear.
Stress-induced changes in the dopamine system
• Dopamine is increasingly thought to play an important role in the pathophysiology of major depressive disorder. Environmental threats perceived by the amygdala increase the levels of dopamine in the prefrontal cortex and the ventral striatum.Local inhibitory feedback ensures a return to homeostasis. However, a severe stressor may disrupt this feedback system by altering striatal levels of brain-derived neurotrophic factor.
Serotonin
Small number of cells produce serotonin. Raphe nuclei - no exact function but moderate the way the whole brain works
Dopamine
Also comes from small number of cells - to whole brain, modulating. Produces pleasure. Tells frontal lobe that you like whatever it is that you are enjoying.
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The mind and the concept of free will22
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Differences between psychology and psychiatry10
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clinical interview49
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research methods25
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Human personality and aetiology38
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Intelligence51
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Memory60
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Attention54
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Working Memory30
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Disorders of Perception, Neglect, Blindsight and Prosopagnosia83
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Judgement and Decision making and Problem Solving52
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Alcohol and other Drugs of abuse44
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Aging27
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Social Psychology55
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PTSD27
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Depression31
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Personality Disorders29
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BPAD30
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ADHD13
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Schizophrenia and Psychosis55
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Anxiety26
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OCD15
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Learning Disabilities65
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Mental disorder and offender behaviour51
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Case studies34
