Depression. Symptoms of depression (ICD-10)

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1 1 Depression Symptoms of depression (ICD-10) General criteria Mild/moderate depressive disorder = at least 2 of these Severe depressive disorder = all 3 Mild depressive disorder = at least 2 Moderate depressive disorder = at least 3 Severe depressive disorder = at least 4 Depressive experience must have a duration of at least 2 weeks. The experience can t be the result of drugs or physical illness Depressed mood that is abnormal for the individual and lasts most of the day every day. Loss of interest/pleasure in activities Decreased energy Low self-esteem Excessive feelings of guilt Thoughts of suicide Lack concentration and find it difficult to make decisions Changes in conscious body movement e.g. walking slowly Sleep disturbance Increase/decrease in appetite and change in weight. Issues concerning the classification and diagnosis of depression Reliability Underlying cause Course of disorder Test-retest reliability Lack of reliable signs Type of clinician Some psychologists diagnose depression as being caused by internal (endogenous depression) or external factors (exogenous depression). This is not considered accurate or reliable as a way to distinguish depression types. Depression types have to be accurately distinguished based on their course e.g. Seasonal Affective Disorder involves depression during winter months. Keller et al. (1995) 524 depressed patients. Tested, then tested again 6 months later. There was a lack of reliability, because there was only a 1 item difference between types of depression. Additionally over the 6 months there may have been changes in the patients. No clear objective measure. Some may attempt to conceal their symptoms. Patients are sent to a psychiatrist after being first diagnosed by a GP. Goldberg and Huxley (1992): 50% of people who are displaying depressive symptoms when being diagnosed by their GP, are not actually diagnosed with depression. van Weel-Baumgarten et al. (2006) GPs do not provide an objective diagnosis, where their previous knowledge of the patient may distort their diagnosis. However, this may be beneficial concerning the background knowledge they may hold.

2 2 Validity Differential diagnosis Depression may be difficult to distinguish from anxiety disorders as well as normal sadness. Depression as a disease Depressed moods may be viewed as normal reactions and it may be inappropriate to label someone as depressed. However, accurate diagnosis is necessary, often to prevent suicide. Dual diagnosis Depression often occurs alongside eating disorders and schizophrenia, so it is difficult to determine which is the primary disorder to treat first. Symptom overlap McCullough et al. (2003): 681 outpatients. There was difficulty distinguishing types of depression because of overlapping symptoms. Gender differences Major depression is found in twice as many women as men. This may be Socio-cultural background influences Cultural differences due to women being more likely to admit their symptoms and seek help. Social minorities tend to have higher rates of depression. This may be due to a diagnosis without recognition of cultural differences in behaviour which are seen as symptoms. Karasz (2005): 36 South Asian immigrants compared to 37 Euro- Americans. The Euro-Americans see depression as being caused by controllable factors and that professional help may be useful, they therefore seek it more. Biological explanations of depression: Genetics Family studies: First degree relatives (offspring, siblings, parents) share 50% of genes and seconddegree relatives 25%. Studies compare rates of depression in relatives of diagnosed cases compared with relatives of controls to determine if those who are more genetically related with a depressed person have more of a chance of developing depression. Twin studies: compare the difference in likelihood of both twins being affected with depression (concordance rate) for identical (MZ) and non-identical twins (DZ). MZ twins have identical genes, so if compared to DZ twins if there is a higher concordance rate for MZ then this indicates the importance of genetics in determining the occurrence of depression. Adoption studies: If depression has a genetic component, it should occur even if there is a change in environment as with being raised by non-biological parents. Family studies: Gershon (1990): 10 family studies. Depression rates in first degree relatives of depressed patients was found to reach 30%. Weissman et al. (1984): relatives of those diagnosed before age 20 had an 8 times greater chance of being depressed. Twin studies : McGuffin (1996): Study of 109 twin pairs. 46% concordance in MZ twins compared to 20% for DZ twins. Bierut et al. (1999): 2662 twin pairs with concordance around 40% in MZ twins. Adoption: Wender et al. (1986): biological relatives 8 times more likely to have depression than adopted relatives. Share the same environment, therefore it may be learned. Concordance is far from 100%, genetics are only a risk factor. Not clear how exactly genes play a role without knowing the specific genes involved. Only certain aspects of depression may be genetic. Symptoms are more likely to be related to genetics, but the number of episodes was linked to life events.

3 3 Biochemical explanation of depression. Changes in levels of neurotransmitters can lead to the symptoms of depression. Noradrenaline: neurotransmitter associated with mood and arousal Serotonin: associated with pleasure and mood Noradrenaline Kraft et al. (2005): 96 depressed patients treated over 6 weeks with SNRI (increases levels of noradrenaline) had a reduction in depressive symptoms compared to those treated with a placebo. Leonard (2000) drugs that lower noradrenaline levels have been found to bring about depressive states. Therefore increasing noradrenaline should decrease depressive symptoms Serotonin Thase et al. (2002): depression related to an overall imbalance between several different neurotransmitters including serotonin and noradrenaline. Mann et al. (1996): impaired transmission of serotonin in depression patients. Amr et al. (1997) Frequency of depression higher in pesticide users. 15 year longitudinal study where pesticide users were compared against matched controls. Pesticides found to lower serotonin levels and increase depression. Delgado (1990): People with a diet in which tryptophan is removed (a chemical used to form serotonin in the brain) were more likely to be depressed. They returned to normal after tryptophan was increased to its natural level. The influence of noradrenaline is recognised by the effects of antidepressant drugs which aim to increase levels of noradrenaline. However, these drugs may also affect other neurotransmitters, so it is difficult to find a clear connection. Julien (2005): depression may be the result of neuron damage rather than neurotransmitter reductions. It may be that depression (including the thought processes and experiences) may lead to the biochemical changes: the direction of causality may be the other way.

4 4 Psychological explanations of depression Psychodynamic explanation of depression Separation/loss of mother in early childhood. Hostile feelings towards parents in childhood are eventually redirected towards the self. If the parent mistreated the child, the trauma may re-emerge as depression in later life. Hinde (1977): When infant rhesus monkeys are separated from their mother they displayed depressive behaviour. Martin et al. (2004): from questionnaires it was found that depressed patients more often report having parents that are affectionless. Harris (2001): The social/financial circumstances are affected after the death of the parent, where the resulting lack of care and family discord could instead be the main factor for increasing the chances of them developing depression. Bonanno (2004): Major losses only lead to depression in less than 10% of cases. Veijola et al. (1998): gender differences from loss of parent: female becomes depressed whereas males become antisocial and alcoholics. Cognitive explanation of depression Hopelessness Attributions concerning experiences of failure: what they think caused the failure. Internal: believe they caused the failure. External: believe the failure was out of their control. Stable: failures will occur over the long-term. Unstable: failure may occur occasionally. Global: one failure indicates to them that they will fail at everything. Specific: failure is specific to the event. Cognitive triad Beck (1967): Negative views about the self, world and future. Advantages Nolen-Hoeksema (1992): 5 year longitudinal study. There is a connection as children grow older between their attribution style and likelihood of developing depression. Seligman (1974) studied college students that failed an exam who were depressed. Those that made unstable and specific attributions were not depressed two days later. Cognitive triad Evans et al. (2005): depressed people have been found to have maladaptive attitudes and beliefs. The more they have the more severe their depression. Disadvantages Ford and Neale (1985): college students that were depressed didn t underestimate their level of control regarding internal/external attributions. Beyer (1998) found that women are more likely to attribute their failures to incompetence and successes to luck. Segal and Ingram (1994): compared nondepressed and depressed individuals: no differences in cognitive vulnerability. Negative thinking is a consequence of depression rather than the cause.

5 5 Biological therapies Drug therapy SRRIs: these drugs prevent the reuptake of serotonin, which results in a higher availability of it. Serotonin is found mainly in synapses of regions of the brain that are related to mood. Kirsch et al. (2008): meta-analysis where SSRIs were compared with placebo. SSRI was more advantageous for severe depression, but not for more moderate depression. Barbui (2008): suicide risk depends on age. Metaanalysis SSRIs increased suicide risk among adolescents. However, there is a decreased suicide risk for adults and those aged 65. (Appropriateness) Ryan (1992): The differences in effectiveness concerning drug treatments may vary because of different in brain neurochemistry during development. (Appropriateness) Ferguson et al. (2005): Meta-analysis comparing SSRI with placebo. SSRI patients are twice as likely to attempt suicide. Doesn t intervene at source Papakostas et al. (2008): meta-analysis comparing the effectiveness SSRIs vs. non-ssri no significant difference between the outcomes for the two treatment groups. Benek-Higgens et al. (2008): Elderly may be misdiagnosed as not being depressed due to lifestyle changes. Therefore, no antidepressant medication is provided when they need it. Additionally, elderly are less likely to seek drug therapy because of stigma. Electroconvulsive Therapy 1) Muscle relaxants are used to paralyse the patient. Short-acting anaesthetic makes them unconscious. These prevent the patient from moving and disrupting the procedure. 2) Unilateral (to the temple of one side of the head) application of a volt current. 3) Shock lasts for 5 seconds causing a seizure which lasts for nearly a minute. The seizure enhances transmission of neurochemicals and improves blood flow to the brain to reduce symptoms of depression. 4) Six sessions are carried out over a few weeks Richards and Lyness (2006): ECT improves 60-70% of those with severe depression Scott (2004): meta-analysis of 18 studies including 1144 patients. It was found that ECT was more effective than drug therapy in the short-term treatment of depression Sackheim et al. (2001): 53% of patients who responded to ECT relapsed Department of Health report (2007): 30% reported permanent fear and anxiety after ECT treatment (Appropriateness). Rose et al. (2003): meta-analysis in which it was found that 1/3 of patients treated with ECT suffered from memory loss (Appropriateness)

6 6 Psychological therapies Psychodynamic therapy Catharsis: emotional release after the psychoanalyst helps the patient uncover unconscious conflicts and anxieties. Encourages patient to have power over their behaviour. Traumatic childhood experiences can be better understood with adult knowledge. Free association: patient says out loud everything that comes to mind. Word association: patient is given words and has to express the first word they can think of that relates to the word offered. Dream analysis: patient talks about their dreams, which are interpreted by the psychoanalyst. Transference: the feelings the patient has towards a family member are acted out on the psychoanalyst. Projective tests: patient says what they think an image is showing. Corsini and Wedding (1995) those who were psychoanalysed, 30 to 60% were cured. Bolger (1989): the idea of being cured is based on the medical model which may not reflect complete recovery. Psychological disorders may not follow a course similar to that of a physical disorder. Eysenck (1952): 66% of control group recovered spontaneously. Only 44% of psychoanalysed group Recovered. Participants may have been too passive to participate in the therapy (relates to appropriateness) Stiles et al. (1991): meta-analysis of 19 studies there was no difference between psychoanalysed and those without treatment after a year. Cognitive behavioural therapy Cognitive part: developing awareness of their beliefs and setting goals Behavioural part: role-playing their beliefs. Beck (1976) Carried out over 20 weeks: 1) Schedule of activities is provided to help them become more active and confident 2) Patient records negative thoughts and acts out those thoughts 3) Therapist helps client recognise the underlying illogical thinking processes. The patient is provided with homework assignments. 4) The therapist helps the patient change their maladaptive attitudes. The patient is tested to see if they can adapt to real-life situations and they are then encouraged to engage in pleasurable activities.

7 7 Brent et al. (1997): 107 adolescents diagnosed with major depression. CBT was the most effective treatment. Provided rapid response and was effective for suicidal adolescents (Appropriateness) March et al. (2007): At the start 30% of the teenagers experienced suicidal thoughts, but this was reduced to 6% by the end of CBT (Appropriateness) Elkin et al. (1985): CBT less suitable for beliefs that are difficult to change (Appropriateness). Simons et al. (1995) CBT less suitable where the source of stress can t be removed easily e.g. debt and divorce (Appropriateness). Kuyken and Tsivrikos (2000) Therapist competence accounts for 15% of variation in CBT effectiveness. Hunt and Andrews (2007): 5 meta-analyses. The median dropout rate was 8%. Patients may have dropped out if they felt therapy wasn t helping. The remaining patients were positive individuals who skewed the results. Specification: need to know Clinical characteristics of depression Issues concerning reliability and validity when diagnosing depression Biological explanations of depression e.g. genetic, biochemical Psychological explanations of depression e.g. psychodynamic, cognitive Biological therapies for depression, including their evaluation in terms of appropriateness and effectiveness e.g. drug therapy and electroconvulsive therapy Psychological therapies for depression including their evaluation in terms of appropriateness and effectiveness e.g. psychodynamic and cognitive-behavioural therapies