Mood Disorders Flashcards
What is more common bipolar disorders or major depressive disorders (MDD)?
MDD
- Lifetime (and 12-month) prevalence estimates of 1.0% (0.6%) for bipolar-I and 1.1% (0.8%) for bipolar-II.
- Lifetime rate of major depressive disorder (MDD) is 10-20%
What is the age onset distribution of major depressive disorder (MDD)?
- Studies across countries have reasonably consistently documented an increasing rate of MDD with an earlier age of onset
What is the gender distribution of type I bipolar disorder, type II bipolar disorder and major depressive disorder (MDD)?
- Bipolar-I: F=M
- Bipolar-II: F>M
- MDD: F2:M1
What are the current diagnostic criteria (according to ICD-10) to diagnose mood (or affective) disorders (4)?
- Where the fundamental disturbance is a change in affect/mood to depression (with or without associated anxiety) or to elation
- The mood change is usually accompanied by a change in the overall level of activity
- Most of the other symptoms are either secondary to, or easily understood in the context of, the change in mood and activity
- Most of these disorders tend to be recurrent and the onset of individual episodes can often be related to stressful events or situations.
What are the current diagnostic criteria (according to DSM-5) to diagnose a depressive episode?
Occurrence of 2 weeks or more of depressed mood
AND the presence of 4 of 8 out of the following:
* Sleep alterations (insomnia or hypersomnia)
* Appetite alterations (increased or decreased)
* Diminished interest or anhedonia
* Decreased concentration
* Low energy
* Guilt
* Psychomotor changes (agitation or retardation)
* Suicidal thoughts
What differentiates bipolar disorder with depressive episodes with Major Depressive Disorder (MDD)?
If no manic or hypomanic episodes in the past are identified, then the diagnosis of a current major depressive episode leads to a longitudinal diagnosis of Major Depressive Disorder (MDD)
N.B. Longitudinal Diagnosis: By asking people about their mental health at regular intervals during their lives longitudinal studies can capture how they are feeling at that point in time.
What are the subtypes (according to DSM-5) for Major Depressive Disorder (MDD) features (3)?
- Atypical features: represent mainly increased sleep and appetite, along with heightened mood reactivity
- Melancholic features: defined by no mood reactivity, along with marked psychomotor retardation and anhedonia
- Psychotic features: the presence of delusions / hallucinations
What are the atypical features that may accompnay a major depressive disorder (MDD) (3)?
- Increased sleep
- Increased appetite
- Heightened mood reactivity
What are the metabolic features that may accompnay a major depressive disorder (MDD) (3)?
- No mood reactivity
- Marked psychomotor retardation
- Anhedonia
What are the psychotic features that may accompany a major depressive disorder (MDD) (2)?
- Dellusions
- Hallucinations
What are the 3 symptom triads of major depressive disorder (MDD)?
- Core symptoms
- Biological symptoms
- Psychological symptoms
What is the core symptoms triad of major depressive disorder (MDD)?
- Low mood
- Anergia
- Anhedonia
What is the biological symptoms triad of major depressive disorder (MDD)?
- Sleep
- Libido
- Appetite
What is the psychological symptoms triad of major depressive disorder (MDD)?
- The world
- Oneself
- The future
What are the current diagnostic criteria (according to DSM-5) to diagnose a manic episode?
Euphoric or irritable mood with 3 of 7 manic 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 or psychomotor agitation
* Impulsive behaviour (such as sexual impulsivity or spending sprees)
What differentiates a manic episode from a hypomanic episode?
- If symptoms are present for minimum 1 week with notable functional impairment, a manic episode is diagnosed
- If symptoms are present for at minimum 4 days, but without notable functional impairment, a hypomanic episode is diagnosed
* Presence of psychotic symptoms indicates manic episode
What are the diagnostic criteria (according to DSM-5) to diagnose type I bipolar disorder?
- If manic symptoms are present for minimum 1 week with notable functional impairment, a manic episode is diagnosed, leading to a DSM-5 diagnosis of type I bipolar disorder
What are the diagnostic criteria (according to DSM-5) to diagnose type II bipolar disorder?
- If not a single manic episode had occurred ever, but only hypomanic episodes are present, along with at least one major depressive episode, then the DSM-5 diagnosis of type II bipolar disorder is made
What are the diagnostic criteria (according to DSM-5) to diagnose unspecified bipolar disorder?
- If manic symptoms occur for less than 4 days, or if other specific thresholds are not met for manic or hypomanic episodes, then the DSM-5 diagnosis: “Unspecified Bipolar Disorder”
Manic episodes can be characterized by psychotic features
- Manic episodes can be characterized by psychotic features (presence of delusions / hallucinations)
- If psychotic features are present, then hypomania cannot be diagnosed (since such features involve notable impairment by definition)
- Similarly, if a patient is hospitalized, irrespective of duration of manic symptoms, a manic episode is diagnosed, not a hypomanic episode
- If manic or hypomanic episodes are caused by antidepressants, then the diagnosis of bipolar disorder is still made in DSM-5
In type I bipolar disorder what is the majority of the first type of episodes?
- Depressive episodes
85% have a depressive as first episode
10% a manic episode
3-5% mixed episode
What type of symptoms are common in the long-term of patients with a bipolar disorder?
- Depressive symptoms
What are the main differences between major depressive disorder (MDD) / unipolar depressive disorder and bipolar disorders when it comes to insight, episode characteristics and genetics (5)?
- In general, insight is preserved in depression, and impaired in mania
- Shorter & recurrent episodes
- Genetic specificity in MDD (manic episodes were found in families with manic episodes, but not in families of persons with unipolar depression)
Describe the attention biases in major depressive disorder (MDD).
- Depression is characterised by biases in maintaining / shifting attention:
- Difficulties for depressed people to disengage from negative material
What neurofunctional abnormalities can explain the attention biases observed in major depressive disorder (MDD)?
- Sustained amygdala response to negative stimuli
- Prefrontal cortex:
- Perigenual anterior cingulate cortex (ACC) appears to mediate negative attentional biases
- Increased lateral inferior frontal cortex associated with the impaired ability to divert attention from task-irrelevant negative information
Observed using fMRI
Describe the memory biases in major depressive disorder (MDD).
- Strong evidence for biased memory processes toward negative material or away from positive material
Memory biases also present in individuals at risk (neuroticism) and in recovered depressed individuals.
Describe the perceptual biases in major depressive disorder (MDD).
- Increased recognition negative faces and / or decreased recognition happy faces
At risk: in neuroticism reduced recognition of happy faces
What neurofunctional abnormalities can explain the perceptual biases observed in major depressive disorder (MDD)?
Enhanced amygdala response to negative faces
ABOUT AMYGDALA: This medial temporal lobe region is involved in the perception and encoding of stimuli relevant to current or chronic affective goals, ranging from rewards or punishments to facial expressions of emotion to aversive or pleasant images and films. While amygdala generally is sensitive to detecting and triggering responses to arousing stimuli, it exhibits a bias towards detecting cues signalling potential threats, like expressions of fear.
What is the effect of an acute single dose of noradrenergic antidepressants on the perceptual biases observed in major depressive disorder (MDD)?
Noradrenergic antidepressants: Reboxetine / Duloxetine
Better recognition of happy faces
What is the effect of an acute single dose of serotonergic antidepressants on the perceptual biases observed in major depressive disorder (MDD)?
Serotonergic antidepressants: mirtazapine
Decreased recognition of fearful faces
What is the effect of a 7 day treatment with noradrenergic & serotonergic antidepressants on the perceptual biases observed in major depressive disorder (MDD)?
- Reduced recognition of anger and fear
- Neurofunctional: reduced amygdala and mPFC response to fear
How can perceptual biases be used as a predictor of clinical response in treating major depressive disorder (MDD)?
- Early change in positive processing (facial expression recognition after single dose) predicts later positive response
Clinical response to (gold-standard SSRI) escitalopram after 6 weeks of treatment is associated with early change [at 1 week] in the amygdala, thalamus, ACC, and insula response to fearful faces
How can baseline ACC activity be used as a predictor of clinical response in treating major depressive disorder (MDD)?
- Elevated baseline ACC activity in depressed patients during tasks that probe affective circuitry (but also executive functions, or self-referential processes e.g., resting state) predict positive response to treatment (i.e. decrease in depression severity following interventions. Both medication, neurostimulation & CBT)
What do psychedelics and SSRIs have in common in terms of function?
Psychedelics: Psilocin/psilocybin, Ayahuasca / DMT, LSD
Have their action in the brain’s serotonin system
What is the main difference between psychedelics and SSRIs in terms of function?
Psychedelics: Psilocin/psilocybin, Ayahuasca / DMT, LSD
- Psychedelics work in the postsynaptic serotonin reuptake receptor (Serotonin 2A receptor) whereas SSRIs work on the presynaptic serotonin reuptake receptor
Same therapeutic effect different adverse effect
How safe are psychedelics?
Psychedelics: Psilocin/psilocybin, Ayahuasca / DMT, LSD
- Non-addictive
- Low physiological & brain toxicity
- Good therapeutic index
What are the therapeutic effects of psychedelics (6)?
Psychedelics: Psilocin/psilocybin, Ayahuasca / DMT, LSD
- Better well-being
- Decreased OCD
- Decreased end-of-life distress
- Decreased addiction
- Decreased depression
- Decreased suicidality
What are the adverce effects of psychedelics (4)?
Psychedelics: Psilocin/psilocybin, Ayahuasca / DMT, LSD
- Dysphoria/anxiety
- Nausea
- Headache
- False memories
What are the direct evidence for 5-HT hypofunction in depression?
Currently none.
What are the indirect evidence for 5-HT hypofunction in depression (9)?
- 5-HT depletion by the antihypertensive drug reserpine could cause depression
- Clinically useful antidepressants all increase synaptic monoamine (some selectively 5-HT) concentrations
- Post-mortem evidence of reduced 5-HT levels in brainstem of individuals who committed suicide
- Lower levels of 5-HT1A-receptors and 5-HT4-receptors
- Monoamine oxidase A increased in MDD
- Blockade of serotonin synthesis by the tryptophan hydroxylase inhibitor p-chlorophenylalanine prevents the antidepressant effects of both MAOIs and TCAs
- Tryptophan depletion (leads to decreased brain serotonin) triggers relapse in MDD successfully treated with SSRIs or cognitive behavioural therapy (CBT)
- Monoamine depletion correlates with decreased mood both in at risk and MDD in remission
- Depression-related traits; “pessimism” and “dysfunctional attitudes” in MDD, and traits “negativism” and “neuroticism” in healthy, related to increased 5-HT2A-receptor (? Serotonin decreased).
Worth noticing that the solidity of the evidence for 5HT deficiency in depression has been challenged in a umbrella review that attracted a lot of attention
