Depression

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Depression
Symptoms of depression (ICD-10)

General criteria           •Depressive experience must have a duration of at least 2 weeks.
                           •The experience can’t be the result of drugs or physical illness
Mild/moderate              •Depressed mood that is abnormal for the individual and lasts most of the
depressive disorder        day every day.
= at least 2 of these      •Loss of interest/pleasure in activities
Severe depressive          •Decreased energy
disorder = all 3
Mild depressive            •Low self-esteem
disorder = at least 2      •Excessive feelings of guilt
Moderate                   •Thoughts of suicide
depressive disorder        •Lack concentration and find it difficult to make decisions
= at least 3               •Changes in conscious body movement e.g. walking slowly
Severe depressive          •Sleep disturbance
disorder = at least 4      •Increase/decrease in appetite and change in weight.


Issues concerning the classification and diagnosis of depression


Reliability

Underlying cause        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.
Course of               Depression types have to be accurately distinguished based on their course e.g.
disorder                Seasonal Affective Disorder involves depression during winter months.
Test-retest             Keller et al. (1995)
reliability             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.
Lack of reliable        No clear objective measure. Some may attempt to conceal their symptoms.
signs
Type of clinician       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.




Adam Clarke www.brain-freeze.co.uk
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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
                        due to women being more likely to admit their symptoms and seek help.
Socio-cultural          Social minorities tend to have higher rates of depression. This may be due
background influences to a diagnosis without recognition of cultural differences in behaviour
                        which are seen as symptoms.
Cultural differences    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 second-
degree 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.

Support                                               Opposition
Family studies: Gershon (1990): 10 family             Share the same environment, therefore it may
studies. Depression rates in first degree relatives   be learned.
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          Concordance is far from 100%, genetics are only
twin pairs. 46% concordance in MZ twins               a risk factor. Not clear how exactly genes play a
compared to 20% for DZ twins.                         role without knowing the specific genes
Bierut et al. (1999): 2662 twin pairs with            involved.
concordance around 40% in MZ twins.
Adoption: Wender et al. (1986): biological            Only certain aspects of depression may be
relatives 8 times more likely to have depression      genetic. Symptoms are more likely to be related
than adopted relatives.                               to genetics, but the number of episodes was
                                                      linked to life events.


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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


Support                                              Opposition
Noradrenaline                                        The influence of noradrenaline is recognised by
Kraft et al. (2005): 96 depressed patients treated   the effects of antidepressant drugs which aim to
over 6 weeks with SNRI (increases levels of          increase levels of noradrenaline. However, these
noradrenaline) had a reduction in depressive         drugs may also affect other neurotransmitters,
symptoms compared to those treated with a            so it is difficult to find a clear connection.
placebo.
Leonard (2000) drugs that lower noradrenaline
levels have been found to bring about depressive
states. Therefore increasing noradrenaline
should decrease depressive symptoms
Serotonin                                            Julien (2005): depression may be the result of
Thase et al. (2002): depression related to an        neuron damage rather than neurotransmitter
overall imbalance between several different          reductions.
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.
                                                     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.




Adam Clarke www.brain-freeze.co.uk
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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.

Support                                               Opposition
Hinde (1977): When infant rhesus monkeys are          Harris (2001): The social/financial circumstances
separated from their mother they displayed            are affected after the death of the parent, where
depressive behaviour.                                 the resulting lack of care and family discord
                                                      could instead be the main factor for increasing
                                                      the chances of them developing depression.

Martin et al. (2004): from questionnaires it was      Bonanno (2004): Major losses only lead to
found that depressed patients more often report       depression in less than 10% of cases.
having parents that are affectionless.

                                                      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                                            Disadvantages
Nolen-Hoeksema (1992): 5 year longitudinal            Ford and Neale (1985): college students that
study. There is a connection as children grow         were depressed didn’t underestimate their level
older between their attribution style and             of control regarding internal/external
likelihood of developing depression.                  attributions.
Seligman (1974) studied college students that          Beyer (1998) found that women are more likely
failed an exam who were depressed. Those that         to attribute their failures to incompetence and
made unstable and specific attributions were not      successes to luck.
depressed two days later.
Cognitive triad                                       Segal and Ingram (1994): compared non-
Evans et al. (2005): depressed people have been       depressed and depressed individuals: no
found to have maladaptive attitudes and beliefs.      differences in cognitive vulnerability. Negative
The more they have the more severe their              thinking is a consequence of depression rather
depression.                                           than the cause.




Adam Clarke www.brain-freeze.co.uk
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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.

Support                                             Opposition
Kirsch et al. (2008): meta-analysis where SSRIs     Barbui (2008): suicide risk depends on age. Meta-
were compared with placebo. SSRI was more           analysis SSRIs increased suicide risk among
advantageous for severe depression, but not         adolescents. However, there is a decreased
for more moderate depression.                       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 70-130volt 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

Support                                              Opposition
Richards and Lyness (2006): ECT improves 60-         Sackheim et al. (2001): 53% of patients who
70% of those with severe depression                  responded to ECT relapsed
Scott (2004): meta-analysis of 18 studies            Department of Health report (2007): 30%
including 1144 patients. It was found that ECT       reported permanent fear and anxiety after ECT
was more effective than drug therapy in the          treatment (Appropriateness).
short-term treatment of depression
                                                     Rose et al. (2003): meta-analysis in which it was
                                                     found that 1/3 of patients treated with ECT
                                                     suffered from memory loss (Appropriateness)



Adam Clarke www.brain-freeze.co.uk
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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.


Support                                        Opposition
Corsini and Wedding (1995) those who           Bolger (1989): the idea of being cured is
were psychoanalysed, 30 to 60% were            based on the medical model which may not reflect
cured.                                         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.




Adam Clarke www.brain-freeze.co.uk
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Support                                             Opposition
Brent et al. (1997): 107 adolescents                Elkin et al. (1985): CBT less suitable for
diagnosed with major depression . CBT               beliefs that are difficult to change
was the most effective treatment. Provided          (Appropriateness).
rapid response and was effective for suicidal
adolescents (Appropriateness)
March et al. (2007): At the start 30% of the        Simons et al. (1995) CBT less suitable where the
teenagers experienced suicidal thoughts, but this   source of stress can’t be removed easily
was reduced to 6% by the end of CBT                  e.g. debt and divorce (Appropriateness).
(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




Adam Clarke www.brain-freeze.co.uk