Depression Flashcards
What system in the brain is involved in depression?
Aversive system
-it promotes survival in event of stress
loss event- depression
threat event- anxiety
what mediates the aversive system?
serotonin
what system in the brian is involved in mania?
Appetitive system
-promotes seeking behaviours
what mediates the appetitive system?
dopamine
what structure in brain is reduced in depression?
hippocampal volume reduced
how is depression diagnosed?
Depressive episodes should last at least 2 weeks (with no hypomanic or manic symptoms)
At least 2 of the following must be present:
-Depressed mood (to a degree that is abnormal for the individual, present for most of day and almost every day, uninfluenced by circumstances, and for at least 2 weeks)
-Loss of interest or pleasure in activities that are normally pleasurable
-Decreased energy or increased fatigue
PLUS at least 4 of:
-loss of confidence or self esteem
-unreasonable guilt
-suicidal behaviours
-complaints of diminished ability to concentrate
-agitation or retardation
-sleep disturbance of any type
-change in appetite
classifications used for depression?
ICD10/11
DSM5
what can be used to assess severity of depression?
-HRSD
-MADRS
Subtypes of depression?
-psychotic depression
-Cotard’s syndrome
-Somatic syndrome
-Atypical depression
-Late onset depression
‘I cant eat because my bowels have turned to durst’
-what subtype
Cotard’s
-weight loss, lack of appetite
-depression worse in morning
-waking in morning 2 hours before usual time
-loss of libido
-loss of interest of pleasure in activities that normally enjoy
-lack of emotional reaction to things they would normally react to
what subtype?
Somatic syndrome
- Mood reactivity (that is, mood brightens in response to actual or potential positive events)
- Significant weight gain or increase in appetite
- Hypersomnia
- Leaden paralysis (heavy, leaden feelings in arms or legs)
- Long-standing pattern of interpersonal rejection sensitivity (not limited to episodes of mood disturbance) that results in significant social or occupational impairment
what subtype?
Atypical depression
Depression occuring for first time in later life
-what subtype?
late onset depression
Occasionally paranoid, typically ‘mood-congrent’ or hypochondiacal
what subtype?
Psychotic depression
what is considered mild depression?
2 key symptoms and
4 symptoms
Key symptoms= low mood, fatigue + anhedonia
what is considered moderate depression?
2 key symptoms
5-6 symptoms
key symptoms= low mood, fatigue + anhedoni
what is considered severe depression?
3 key symptoms (fatigue, low mood + anhedonia)
>7 symptoms
spontaneously resolving brief depressive episode following childbirth (50% of women)
-what subtype
post partum depression
recurrent depression in winter months
-what is this + what is treatment?
seasonal depression
-treat with bright light therapy
what is the monoamine hypothesis?
Depression is thought to be related to monoamine deficiency
-so medications which increase monoamine activity reduce depressive symptoms
what are examples of monoamines?
-Serotonin (5-HT)
-Dopamine
-Noradrenaline
what role does stress play in depression?
Stress releases cortisol
-Chronic stress can cause cortisol dysregulation
Excess cortisol may cause depression through:
-neuronal damage (low hippocampal volume)
-release of proinflammatory cytokines
what are the mofa of antidepressants?
Increase monoamine activity by two main mechanisms:
Reuptake inhibition- Keep monoamine in synaptic cleft
Monoamine oxidase inhibitors- Prevent removal of monoamine from presynaptic neuron
examples of tricyclic antidepressants?
-amitriptyline
-Imipramine
MofA tricyclic antidepressants?
inhibit the reuptake of serotonin + noradrenaline (keeping monoamines in synaptic cleft)
Monoamines= serotonin, dopamine and noradrenaline
SE of tricyclic antidepressants?
-QT prolongations
-seizures
-anticholinergic
examples of SSRIs?
-sertraline
-citalopram
mechanism of action SSRIs?
Inhibit reuptake of serotonin in the monoamine synaptic cleft
examples of monoamines= serotonin, dopamine and noradrenaline
SE of SSRIs?
-Self harm risk
-sexual dysfunction
-nausea/ tremor/ headache
examples of SNRIs?
-venlafaxine
-Duloxetine
mechanism of action of SNRI?
Seretoning and noradrenaline reuptake inhibitors (keeping monoamines in synaptic cleft)
Monoamine= noradrenaline, serotonin and dopamine
mofa- monoamine oxidase inhibitors?
Prevent removal of monoamine from presynaptic neurone
+ also break down tyramine
examples of reversible + irreversible monoamine oxidase inhibitors?
irreversible= phenylzine
reversible= moblecamide
why can people on monoamine oxidase inhibitors not eat cheese, beer or wine?
-because monoamine oxidase inhibitors break down tyramine
cheese, wine + beer contain tyramine
If someone on monoamine oxidase inhibitor eats something with tyrosine in it they can have a hypertensive crisis
more likely to have a hypertensive crisis with phenylzine or moblecamide?
more likely with phenylzine because it is irreversible
Moblecamide= reversible monoamine oxidase inhibitor
example of atypical antidepressant?
Mirtazapine
mofa atypical antidepressants (mirtazapine)?
Mixed receptor effects:
Alpha-2
5-HT2
AND
5-HT3
when would an atypical antidepressant be used?
after a trial of SSRIs
-especially useful if patient has had trouble sleeping
what is the diagnosis?
serotonin syndrome
what causes serotonin syndrome?
Caused by excess of serotonin in synaptic cleft
Most often caused by combination of SSRI and MAOI
-St Johns wort and SSRI may cause this
How does serotonin syndrome present?
Neuromuscular excitation- hyperreflexia, clonus, myoclonus
Altered mental status- delirium, agitation, insomnia
Autonomic dysregulation- tachycardia, high temperature, shivering, sweating and diarrhoea
what can a prolonged fever for serotonin syndrome lead to?
-rhabdomyolysis
-metabolic acidosis
-renal failure
-DIC
treatment of serotonin syndrome?
-benzodiazepines for agitation
-if severe ventilation and sedation
May use cyproheptadine (seretonin receptor antagonist) however little evidence
treatment mild depression?
no treatment, watchful waiting and assessing again in 2 weeks
2 key symptoms (fatigue, low mood + anhedonia)
4 other symptoms
treatment of moderate/ severe depression?
CBT
1st= SSRI (if no benefit in 6 weeks change) e.g. sertraline, escitalopram, fluoxetine
2nd= switch SSRI
3rd= consider another class of antidepressant e.g. SNRI venlafazine, tricyclic antidepressant (amytriptyline) or an MAOI (phenyzine/ meblocamide)
Moderate= 2 key symptoms (fatigue, low mood + anhedonia) + 5/6 other symptoms
Severe= 3 key symptoms + >7 symptoms
is sertraline or fluoxetine preferred in children/ young people?
fluoxetine
treatment is psychotic depression?
+ antipsychotic
treatment if life threatening or rapid response needed?
ECT
what antidepressant when used with an NSAID risks GI bleed?
SSRI + NSAID risk GI bleed
-and so warrant a PPI
how should SSRIs be stopped?
-gradually over 4 weeks
what type of antidepressant can cause hyponotraemia?
SSRI
can you take triptans and SSRIs together?
No- avoid triptans when on SSRI as they can lead to serotonin syndrome
