Depression Flashcards
Past history of depression?
initially called ‘melancholia’. Earliets accounts = 2nd millenium BC. Hippocrates believed it was too much black bile in the spleen
Who is a case study of MDD?
Joseph Westbecker
How does DSM-IV-TR define major depressive disorder in terms of symptoms?
Presence for at least 2 weeks of at least 5 of the following - depressed mood diminished interest or pleasure agitation fatigue weight/appetite loss/gain Worthelssness/excessive guilt
What is the prevalence of MDD?
5%
How long do MDD episdoes normally last?
1/4 = less than a month
Furhter 50% = resovled in less than 3 months
What is the typical age of onset of depression?
24-29
Sex diffs in depression?
Women about 2 x as likely as men to report depression (Kupfer et al, 2012)
Two experiments regarding genetic influences on MDD?
Mcguffin et al, 1996
Wender et al, 1986
What did Mcguffin et al do?
1996 - MZ twins = 46% concordant for depression. DZ twins = 20% convergece
What did Wender et al, 1986 do?
Relatives of depressed people = 8x more likely to have major depression and 15x more likely to attempt suicide then relatives of non-depressed
How well ahve attmepts gone to identifiy specific genes responsible for these genetic infrlunces?
They haven’t yet been succesful
Two examples of biological influences on depression?
Thase, 2009
Rampello et al 2000
What did Thase 2009 do?
Some role of dopamine dysfunction in at least some forms of depression in keeping with anhedonia hypothesis – important symptom of depression == inability to experience pleasure
What did Rampello et al do?
2000 - result of an imbalance between several neurotransmitters including serotonin, noradrenalin and dopamine
What role does serotonin have?
It provides overall control. Low levels disrupt activity in these systems = depression
what is the major brain area involved in depression?
limbic system
What two neurotransmitters are heavily implicated in depression?
Serotonin and noradrenalin
Immune system and depression..?
Depression is thought to be accompanied by dysregulation of the immune system.
Dowlatti et al (2010) did a review – depression is associated with acitvation of the inflammatory response system as evidenced by increased production of pro-inflammatory cytohines such as interleukin and interferon. These can both directly contribute to the development of depressive symptoms
Two examples of evidence with neuroimaging and depression:
Davidson et al 2009
Nusslock et al 2011
What did Davidson et al 2009 show?
Damage to the left, but not the right anterior PFC often leads to depression
People with depression show relatively low acitiy in the left hemishpere prefrontal regions and relatively high activity in right hemisphere
What did Nusslock et al 2011 show?
Left frontal asymmetry in never depressed individuals predicted onset of major and minor depressive episodes over a 3 year period
Three examples of envionrmental impact on depression?
Monroe et al 2009
Monroe & Hadjiyannakis, 2002
Monroe & HArkness, 2005
What did Monroe et al 2009 do?
severely stressful life events often serve as precipitating factors for unipolar depression
What did Monroe & Hadjiyannakis, 2002 show?
People with depression who have experienced stressful life event = tend to show more severe symptoms than those who haven’t
What did Monroe & HArkness, 2005 show?
about 70% of people with 1st onset of depression have had a recent major stressful life event
Who are the most prone to depression?
Brown & HArris (1978) - working class women, with more than 3 children, no close confidantes, unemployed, father died when young = most prone to depression
Why are females more prone to depression?
More reeponsibilities and lower quality of life. Subejct to cultrual pressures
More likely to attribute failure to personal characteristics
Helen-Hoekseme (1990) – men are more able to distract themselves from negaitve thoughts
Tsai et al (2005) – physila illness in elderly contributes to risk of depression
What was Freud’s view on depression
similar to grieving. Individuals regress to oral stage as a defence mechanism against stress.
Depression results from an imagined or symbolic loss
Most prone = people who fail to progress through the oral stage
What was the learned helpness theory?
Seligman (1975) - should know this from previous exams
Who had a cognitive based theory
Beck (1997)
What did Beck’s theory invovle?
1997 – cognitive symptoms of depression often precede and cause the affective/mood symptoms.
Dysfunctional beliefs (formed in childhood) – predispose person holding them to develop depression if they experience something relating to the belief
Negative cognitive triad - self, environemtn adn future
Two main types of anti=depressants?
Tricyclics and selective serotonin reuptake inhibitor (SSRI)
What do tricyclics do?
Increase neurotransmission of the monamines. Efficiency = widely demonstrated. Only about 50% however show clinically sign improvement
Unpleasant side effects.
Are the side effects of tricyclis or SSRIs worse?
Anderson (1998) – 14% of patients on tricyclics discontinue use due to side effects vs 9% SSRIs