Mood disorders Flashcards
What criteria is used to classify mental disorders?
DSM-5
What is the WHO’s classification system of mood disorders?
ICD-10
What is the Kraepelinian definition of MDI?
Any recurrent mood episodes of any kind (depressive or manic) constituted the diagnosis of MDI, thus MDI meant bipolar illness plus unipolar depressive illness.
What is mood disorder?
Fundamental disturbance is a change in affect or mood to depression or to elation
Usually accompanied by a change in the overall level of activity.
Recurrent, onset can be related to stress events
What is more common bipolar or MDD (major depressive disorders)?
MDD - 10-20%
Bipolar-1 is 1.1%
What is the DSM-5 criteria for depressive episodes in terms of time?
Occurrence of minimum of 2 weeks or more of depressed
What are the core symptoms of depressive episodes?
Low mood and anhedonia
What are the core symptoms of manic depressive disorder?
Low mood
Anergia
Anhedonia
what are the biological symptoms of Manic depressive disorder?
Sleep
Libido
Appetite
What is the DSM-5 criteria for mania/bipolar?
3 or more of 7 criteria:
Decreased need for sleep with increased energy
Distractibility
Grandiosity or inflated self-esteem
Flight of ideas or racing thoughts
Increased talkativeness or pressured speech
Increased goal-directed activities of psychomotor agitation
Impulsive behaviour (sexual impulsivity or spending sprees)
How is a manic episode diagnosed?
if such symptoms are present for a minimum of 1 week with notable functional impairment, a manic episode is diagnosed -> Type 1 bipolar disorder
What type of bipolar is associated with a manic episode?
type 1
How is a hypomanic episode diagnosed?
If such symptoms are present for a minimum of 4 days, without notable functional impairment
How is a type-II bipolar disorder made?
Only hypomanic episodes along with a last one major depressive episode
If manic symptoms occur for less than 4 days, what is the DSM-5 diagnosis?
unspecific bipolar disorder
Why is hypomania not diagnosed in hospitalised patients or those who present with psychotic symptoms?
Since per definition this is associated with functional impairment.
What term refers to a swing in mood?
Cyclothymia
In bipolar-1 what are the first type of episodes?
Depressive episodes (85% of cases)
What type of symptoms are common in the long-term of bipolar disorder?
Depressive symptoms
What is prevalent between mania and depression?
Anxiety “Anxious distress specifier”
In terms of onset what is the difference between bipolar and unipolar depression?
Age of onset is earlier in bipolar (19 years v late 20s)
In terms of depressive episodes what is the difference between bipolar and unipolar depression?
Shorter depressive episodes in average <3m
v 6-12m in unipolar
What are the main differences between unipolar and bipolar depression?
In terms of bipolar:
Earlier age of onset
Shorter depressive episodes
Recurrent course (More frequent episodes)
Genetic specificity (manic episodes were found in families with manic episodes, but not in families of persons with unipolar depression)
Differential treatment (antidepressants for unipolar depression v neuroleptics)
What is the main treatment for mania?
Neuroleptics and lithium
Which mental disorder has the highest amount of heritability?
Bipolar disorder
What mood disorder diagnosis can easily be missed and what diagnosis is a patient in that case likely be mis-diagnosed with?
Bipolar diagnosis might be missed in a patient due to a lack of insight about mania/hypomania. Patient may end up with a MDD diagnosis despite a history of manic episodes.
Collateral information often useful, in particular if you are in doubt about history details.
What are the problems concerned with a mis-diagnosis of bipolar?
Incorrect treatment using anti-depressants
-Ineffective in acute bipolar depression and in prophylaxis
-Can cause acute manic/hypomanic episodes
Shown to worsen long-term course of bipolar illness.
Rapid-cycling cases appear to lead to more mood episodes, including depressive states
What is attention bias in depression?
Depression is characterised by biases in maintaining/shifting attention = difficulties for depressed people to disengage from negative material
Prolonged maintenance of attention to negative stimuli, and reduced to +.
What imaging is used in assisting with diagnosis of depression?
functional magnetic resonance imaging (fMRI).
How does fMRI work?
Works by detecting changes in blood oxygenation and flow that occur in response to neural activity - brain more active = increased oxygen consumption to satisfy the blood demand to the active area.
Oxygenated blood has different magnetic susceptibility relative to deoxygenated blood.
Changes in the ratio of oxygenated/de-oxygenated blood.
The haemodynamic response function can be inferred by fMRI by measuring the blood-oxygen level dependent response.
Which cerebral region is deeply involved in attentional biases?
Amydala response to negative stimuli
Prefrontal cortex:
-Perigenual anterior cingulate cortex (ACC) mediates negative attentional biases
Which cerebral cortex mediates negative attentional biases?
Preigenual anterior cingulate cortex
Which cerebral structure is associated with the impaired ability to divert attention from task-irrelevant negative information?
Latereal inferior frontal cortex
What type of memory biases exist in patients with depression?
preferential recall of negative compared to positive material
Memory biases present in individual at risk (neuroticism) and in recovered depressed individuals.
How are cognitive biases assessed?
Facial expression recognition (Harmer) task
Results: Recognition of negative faces (Increased) and a decreased recognition of positive expressions.
Which personality trait increases risk of developing depressive disorders?
Neuroticism
What function is performed by the amygdala?
The medial temporal lobe region is involved in the perception and encoding of stimuli to current or chronic affective goals, ranging from rewards or punishments to facial expressions of emotion to aversive or pleasant images and films
Sensitive to detecting and triggering responses to arousing stimuli, it exhibits bias towards detecting cues signalling potential threats (fear)
What biases are exhibited by the amygdala?
Bias towards detecting cues signalling potential threats
What types of drugs are used in the treatment of depression?
Serotonin re-uptake inhibitors
TCA ADs
Which types of drugs are associated with a better recognition of positive facial expressions in depressive treatment?
Noradrenergic antidepressants
Which antidepressant causes decreased recognition of fearful faces?
Mirtazpine (sertonergic antidepressants)
What happens to baseline ACC activity in patients with depression in tasks that probe affective circuitry?
Elevated
Which midbrain nuclei contain serotoninergic cell bodies?
Raphe nuclei
What does the monoamine deficiency hypothesis state?
Postulates that depressive symptoms arise from insufficient levels of monoamine neurotransmitters serotonin (5-HT), NA and/or dopamine
Which antihypertensive has been potentially associated with 5HT depletion?
Reserpine
What is the overall pharmacological aim for antidepressants?
Increase synaptic monoamine concentration
What do post-mortem evidence of depressed patients suggest in terms of monoamine?
There is reduced 5-HT levels in brainstem individuals who committed suicide
Which types of receptors are reduced in patients with depression?
Lower levels of 5-HT1A-receptors and 5-HT4 receptors.
Which enzyme is elevated in MDD?
Monoamine oxidase
Which inhibitor prevents the antidepressant effects of both MAOIs and TCAs?
Tryptophan hydroxylase
This causes tryptophan depletion leading to less serotonin.
What does monoamine depletion correlate with?
Correlates with low mood both in at risk and MDD in remission
What are depressive related traits?
Pessimism and dysfunctional attitudes in MDD and traits negativism in health, related to increased 5HT2A receptors
Which serotonin receptor is inversely related to concentrations of serotonin?
The 5-HT2A receptor
Which imaging is used to detect 5HT receptors?
PET imaging
What is injected in patients during PET scans?
Radioactive tracers that binds to a specific target (receptors).
After a baseline PET scan is conducted what pharmacological treatment is administered to quantify the number of dopamine?
Amphetamine challenge - releases dopamine from dopaminergic neurones, competing with the radiotracer.
-Difference in binding of the tracer represents as a measure the amount of dopamine released in response to the challenge.
