Clinical Characteristics of Depression
You only need 5 of these symptoms to be classified as clinically depressed, also you only need these symptoms for 2 weeks:
- Increase appetite and wieght gain (a change of 5% of body weight in a month)
- Insomnia or Hypersomnia
- Sad/ depressed mood
- Poor appetite and weight loss (a change of 5% of body weight in a month)
- Loss of interest and pleasure in usual activities
- Difficulties in concentrating
- Loss of energy or fatigue
- Feelings of worthlessness or innapropraite guilt
- Recurrent throughts of death
To be classified as depressed you MUST have either:
- Depressed mood
- Loss of interest or pleasure in regular activities
Issues Surrounding the Classification and Diagnosi
- Depression should not be ‘meidcalised’. The argument goes that all humans have mood levels; this makes it difficult to place the point for diagnosis of depression, and if there should be such a point.
- The criteria is too broad. The symptoms of depression as outlined in the DSM criteria could be experienced by a range of people in unhappy situations or with abnormal personalities. A minimum of 5 symptoms is a relatively undemanding criteria required for diagnoses.
- It can be sometimes difficult to distinguish between various types of depression. This leads to low validity of diagnosis as types are often confused.
- Depression may be co-morbid with other syndromes at one time, and it can be difficult for doctors to decide which is the primary disorder to treat.
- Most people are treated for depression by their GP, however many GP’s frequently do not recognise the symptoms as depression. They may not be as well trained in depression.
- The DSM is based on west culture’s symptoms of depression, and therefore these symptoms may not be applicable worldwide.
- Depression is not wholly medical, it assumes it is not a psychological disorder, and enters the nature vs. nurture argument. Yet drugs are only 50% effective.
- Depression is twice as common in women as in men, which may be partly due to diagnostic biases.
Biological Explanations of Depression
The four main reasons for depression having a biological cause are:
- Physical Changes
- Genetic Concordance
- Successful Drug Treatments
- Injury can cause depression
These were devised by Hammen in 1997
The Two main biological explanations you need to know are:
- Genetic Factors
- Biochemical Factors
Biological Explanations- Family Studies
- Having a parent of a sibling with depression may be a risk factor for developing depression.
- Studies involving families identify individuals who have depression and whether there are any links with other family members.
- Research has highlighted suffering from depression have a 1 in 5 chance of having a relative with the disorder.
- This is in contrast to the 1 in 10 chance of having depression in comparison with the entire population (Harrington et al. 1993)
Biological Explanations- Twin Studies
- The highest genetic concordance had been found between identical twins who have bipolar depression (60%).
- There have been a number of twin studies comparing identical and non-identical twins. These studies provide the most convincing evidence for genetic links.
McGuffin et al (1996) studied 177 sets of twins with depression.
- The concordance rate in identical twins was 46% compared to 20% in non-identical twins.
Biological Explanations- Adoption Studies
Wenda et al. (1986) studies adopted individuals who had been hospitalised due to depression and also studied their non hospitalised biological relatives.
Depression was significantly higher in the biological relatives of the depressed adopted individuals compared to the relatives of a control group of non-depressed individuals.
The biological parents were 8 times more likely to have depression than the adoptive parents.
Biological Explanations- The Diathesis-Stress Mode
Depression is innate but wont be set off until environmental factors.
The researchers found that if one twin already had depression, the likelihood of the second twin developing depression was much higher when faced with negative life events.
- Monoamine Neurotransmitters is the name for serotonin, noradrenaline and to a lesser extent dopermine.
- Monoamine Neurotransmitters are particularly active in areas of the brain which are associated with reward and punishment. They also regulate the hypothamulus, which is involved in sleep and appetite
Monoamine Neurotransmitters not able to work =depressive symptoms
Biological Explanations- Supporting research
Bunny et al. (1965)
- That there were low levels of noradrenaline in the brain of the individuals suffering from depression.
- Addition post-mortem research found that there were a decreased number of noradrenaline receptors in the brains of suicide victims.
Delegado et al. (1990)
- Fed deprived participants a special diet which lowered their levels of tryptophan.
- Individuals experienced a rise in depressive symptoms until their diets were stopped.
- The depressive symptoms then subsided as their serotonin (and tryptophan) levels increased.
Biological Therapies for Depression- Drugs
MAOI's- effectively treat the symptoms of depression. Frequent side effects. Only usually prescribed for people who cannot take other medications. Due to clashes it is rarely used.
Tricyclics- Raises level of Serotonin and noradrenaline in the brain. Highly effective in reducing symptoms.
SSRI's- Increases the amount of serotonin by blocking up the re-uptake. Few side effects. Considered to be the drug of choice but potential links with suicidal behaviour.
Biological Therapies for Depression- ECT
Patient is put to sleep and given a nerve blocking agent. A small electrical current of 0.6 amps causing a small seizure of 1 minute. This process is repeated 3 times a week, and roughly 3-15 treatments are given.
It can cause memory loss. There are ethical considerations, and it can also cause irregularity of the heart beat.
Patients whom normal medication and therapy have proved ineffective will use ECT, it is used for patients who suffer from Schizophrenia and have a high risk of suicide. It should only be used as a last resort.
Biological Therapies for Depression- Photo Therapy
It works by exposure to light usually controlled with various devices. A specific amount of time at a specific time of day.
The risks are jumpiness or jitteriness. Headaches and nausea is also a risk.
People with SAD are most likely to use this therapy, its used for people who don't respond well to anti-depressant drugs.
Evaluating Biological Therapies
Kirsch et al. (2008)- Concluded that there was only a significant advantage to using SSRI's with individuals who had severe depression. They also found that when a placebo was used, it worked for individuals who had mild to moderate depression but not severe depression.
Geller er al. (1992)- The study failed to find evidence that antidepressants were any more effective that placebos.
Barbui et al. (2008)- high risk of attempted suicide whilst taking SSRI's.
Rush (1995)- ECT is extremely effective in cases of severe depression, particularly where the patient is likely to be suicidal
Davanand et al. (1994)- No convincing evidence that ECT causes long-term memory deficits or any structural brain damage.
Rose et al. (2003)- Identified 1/3 of persistent memory loss after ECT.
It is unclear how photo therapy works and its effectiveness.
Evaluation of Drug therapies
- Everyone reacts to drugs differently
- There are environmental factors which must be considered
- Placebo effect is 40%
Drug therapy is not always the most appropriate form of treatment to use as the depression may be a psychological problem.
Psychological Explanations of Depression- Cognitiv
Aaron Beck (1967)- depression is a result of having negative interpretations of the world. Depressed individuals have a negative schemata formed through life experiences. Cognitive biases are then formed. They are trapped within the negative triad; a pessimistic view of the self, world and future.
Seligman (1975)- concluded depression is the result of learned helplessness. It occurs when a person has previously tried to take control of a situation and failed. They then feel as if they have no control over their life and become depressed. The feeling of lack of control and helplessness is then applied to other situations, even though they may have had control over these situations before depression took hold.
Psychological Explanations of Depression- Psychody
Freud believed that everyone harbours unconscious negative feelings towards people that they love. Once a loved one leaves we are left in mourning or melancholy, people get stuck at this point, causing self-abuse and self-blame to be directed inwards, this then turns into depression.
Freud (1917)- termed negative thourghts directed inwards as 'anger turned against oneself'.
Shah and Waller (2000)- Found individuals who suffer from depression describe their parents as being 'effectionless'.
Barnes and Prossen (1985)- Men who's fathers died during childhood scored higher on a depression scale that those who grew up with their fathers.
Psychological therapies- Cognitive Behavioural The
16-20 sessions focused on the behavioural problems and dysfunctional thinking. Two main stages; thought catching, and behavioural activation. Thought catching is the link between how they feel and the way they think. Negative thoughts highlighted and replaced with realistic thoughts. Behavioural activation is where the client is encouraged to engage themselves in physical exercise.
It is difficult to predict how the client will react. They client is liable to become dependant on their therapist. It also depends on the clients co-operation as they need to be willing to discuss their feelings.
It is used to treat people who have depression and want to change, and are willing to open up to a therapist.
Psychological Therapies- Interpersonal Psychothera
12-16 weeks long. Involves therapeutic conversation, talking through problems. It has 3 main stages; Identification of main problems, working through identified problems and consolidation of what has been learned and how it can be applied to help the client in the future.
It is not extensively researched, so the risks are fairly unknown. It is not clear the group of patient it is likely to be most effective for.
It is not clear the type of depressed people it is likely to treat, however their co-operation is vital.
Evaluating Psychological Therapies
Kuyken et al. (2007)- CBT is effective at reducing symptoms of depression and in preventing relapse.
Fava et al. (1994)- CBT is as effective as medication, may be superior to drug therapies in treating the residual symptoms.
Keller et al. (2000)- A combination of drug and CBT is most effective- working around 85% of the time. CBT alone is only effective 52% of the time.
Simons et al. (1995)- CBT is not effective for people who are resistant to change and have rigid attitudes.
Elkin et al. (1989)- IPT is as effective as CBT and drug therapy in the reduction of depressive symptoms.
Joiner et al. (2006)- There is a lack of extensive research into IPT and therefore it is difficult to identify its overall effectiveness.
Evaluation of psychological therapies
-Everyone reacts differently to therapy
-Patients need to be followed up to see if the therapy works well, that is expensive so limited data is available on these therapies.
Psychological therapies may not always be the most appropriate method of treatment as it may be a biological problem.