Week 3 - Mood disorders Flashcards
Define mood
Subjective internal feeling experienced by the person through their emotions
Define affect
Objective observation of how a person outwardly presents
Define a mood disorder
- extreme fluctuation in a persons mood
- impacts their thinking, emotions and behaviour
- is chronic and persistent
Define major depressive disorder
experience of a depressed mood or loss of pleasure or interest in activities for at least 2 weeks which impacts on functioning
Identify the signs and symptoms of major depressive disorder
- depressed mood (most of the day, nearly every day)
- marked loss of interest in activities
- change in weight without weight loss attempt
- insomnia or hypersomnia
- observable psychomotor agitation or retardation
- loss of energy/fatigue
- feelings of worthlessness
- loss in concentration/ability to think
- recurrent suicidal ideation
Biological causes of major depressive disorder
Serotonin and norepinephrine (neutrotransmitters)
* decreased sensitivity of serotonin receptors
* decreased serotonin levels
* decreased release of norepinephrine into synaptic cleft
Dopamine (neurotransmitter)
* decreased dopaminergic activity
HPA axis (hormones)
* Increased HPA axis activity -> chronic stress
* increased cortisol levels
Genetic predisposition and family history (in combination with environmental factors)
Structural variations in the emotion-regulating regions of the brain (smaller hippocampus)
Sleep
* decreased amount of deep sleep
* increased nocturnal arousal (insomnia)
Presence of comorbid chronic illnesses
Psychological causes of major depressive disorder
Negative thinking
* thinking style which focuses on inability or inadequacy to get through life events
Rumination
* makes a person more likely to develop depression
* also contributes to a person experiencing an episode of depression for longer as they ruminate on their depression
Environmental causes of major depressive disorder
- Stress of life events (relationship breakdown, loss of employment, death of a loved one)
- substance misuse
- loneliness and isolation
- family trauma and childhood trauma
- cultural aspects (migration, distrimination, loss of identity)
- giving birth
SSRIs
selective serotonin reuptake inhibitors
First line treatment for major depressive disorder
MOA: inhibits the reuptake of serotonin at the synaptic cleft to increase serotonin activity
takes 2-4 weeks to take therapeutic effect
eg. prozac, zoloft, lexapro, luvox
Side effects: fatigue, hot flashes, insomnia, headache, tremor, sexual dysfunction
Avoid concurrent administraation with other SSRIs, MAOIs and St John’s Wort
SNRIs
serotonin-noradrenaline reuptake inhibitors
MOA: Inhibit the reuptake of serotonin and norepinephrine at the synaptic cleft, increasing the activity of these neutrotransmitters in the brain
Takes 2-4 weeks to take therapeutic effect
eg. Duloxetine
Side effects: dry mouth, fatigue, naursea and vomiting, diarrhoea and constipation
Avoid concurrent administration with SSRIs, MAOIs, and St Johns Wort
TCAs
Tricyclic antidepresssants
second line of treatment for major depressive disorder
MOA: Inhibit the reuptake of serotonin and norepinephrine at the synaptic cleft, increasing the activity of these neurotransmitters in the brain (are more selective to one or the other than SNRIs)
Takes 2-4 weeks to take therapeutic effect
eg. Amitriptilyne, Imipramine
Side effects: sedation, postural hypotension, arrhythmias, urinary retention, disorientation/confusion in elderly
Avoid concurrent administration with SSRIs, alcohol, antipsychotics, and MAOIs
MOAIs
Monoamine oxidase inhibitors
Not widely used due to significant side effects
MOA: ihnibits monoamine oxidase from metabolising serotonin, norepinephrine and dopamine (monoamines)
Takes 2-4 weeks to take therepeutic effect
Side effects: hypertensive crisis
* MOAIs also inhibit the metabolism of tyramine, which can build up in the bloodstream to cause a hypertensive crisis
* requires diet control for many spoiled/aged/fermented products
Side effects of antidepressant medications
Serotonin syndrome
* fatal excessive concentration of serotinin in the CNS
* agitation, tremor, fever, shivering, muscle spasms, ataxia, diaphoresis, hyperreflexia, changes in mental state
* perceptual disturbances, blood pressure changes, loss of coordination, N+V
Antidepressant discontinuation syndrome
* withdrawal after abruptly ceasing or changing antidepressant
* non-life threatening
* irritation, anxiety, nausea, anorexia, diaphoresis, paraesthesia, sleep disturbances, headache, vertigo
* engage in monitored titration to wean antidepressants and understand the dosage and half life of the drug
Suicidality
* significantly increased incidence in suicidal thoughts, feelings and behaviours
Identify and explain non pharmacological treatments for major depressive disorder
Early intervention
Cognitive behavioural therapy
Behavioural strategies
Cognitive strategies
Talk therapy and group therapy
Exercise
Identify and explain last resort physical treatments for major depressive disorder
Electroconvulsive therapy
* supervised medical procedure
* brief electrical stimulation of the brain under anaesthesia
* number of sessions dependent on clinical response
* consent as per mental health act 2014
Indications
* MDD
* psychotic symptoms
* responded well to ECT previously
* limited/poor response to other treatment
* suicidal
