DEPRESSIVE DISORDERS Flashcards
What is the lifetime risk of a woman developing diagnosed depression?
10-25%
What is the lifetime risk of a man developing diagnosed depression?
5-12%
What is the average age of onset for depression?
Late 20s
How much of a part do genetics play in depression?
Twin studies show the heritability of depression is between 40-50%. Some evidence shows that a particular allele for the serotonin transporter gene is associated with an increased risk of depression, but only in those who experience an adverse life event.
What early life experiences might lead to someone developing depression?
Parental separation during childhood
Neglect
Physical and sexual abuse
What personality traits are most associated with depression?
Neuroticism - anxious, shy, moody, easily stressed
What are the neurobiological factors associated with an increased risk of developing depression?
Reduced volume of the hippocampus, amygdala and certain regions of the frontal cortex.
What are the two main neurotransmitter pathways associated with depression?
Overactivity of the hypothalamic-pituitary-adrenal (HPA) axis
Deficiency of monoamines (noradrenaline, serotonin, dopamine)
What are the three core symptoms of depression as described by the ICD-10?
Depressed mood - varies little from day to day and is unresponsive to circumstances.
Markedly reduced interest in almost all activities (anhedonia) - associated with the loss of ability to derive pleasure from activities
Lack of energy - increased fatiguability on minimal exertion leading to diminished activity (anergia)
What are the biological (somatic) symptoms associated with depression?
Problems with sleep - especially early morning wakening
Depression worse in the morning
Marked loss of appetite - might have weight loss as a result
Psychomotor retardation or agitation
Loss of libido
What are the cognitive symptoms associated with depression?
Reduced concentration and memory Low self esteem Guilt Hopelessness Thoughts of suicide or self harm
What are the ICD-10 criteria for a depressive?
At least 2 of the core symptoms present for at least 2 weeks:
Depressed mood
Loss of interest and enjoyment
Reduced energy or increased fatiguability
AND at least 2 of the following: Reduced concentration Reduced self esteem Ideas of guilt Bleak and pessimistic views of the future Ideas of acts of self harm or suicide Disturbed sleep Diminished appetite
How is the severity of depressive episodes graded according to the ICD-10 criteria?
Mild: total of four or five symptoms, where most normal activities are continued
Moderate: total of six or seven symptoms, where the patient finds it difficult to continue normal activities.
Severe: total of eight or more symptoms including all three core symptoms, unable to continue normal activities
What grade of severity is given to a depressive episode if the patient is experiencing psychotic symptoms?
Severe
What is dysthymia?
Chronically depressed mood with periods of wellness in between. The patient’s low mood rarely (if ever) meet the criteria for the mild depressive episodes.
What investigations might you do for a patient who presents with the signs and symptoms of depression?
Gather collateral history - family and GP
Ask patient to keep a mood diary
Beck Depression Inventory (BDI)
Hospital Anxiety and Depression Score (HADS)
FBC
U+Es - baseline for elimination of medication
LFTs - baseline for elimination of medication
TFTs
Is there a link between self-harm and suicide?
Yes. A patient who presents with self-harm have a 100-fold greater chance of completing suicide in the following year compared to the general population.
What are the epidemiological risk factors for suicide?
Male LGBT Prisoners Being unmarried (seperated > widowed > single) Unemployment Certain occupations - Farmer, vet, nurse, doctor) Low SES Social isolation
What are the clinical risk factors for suicide?
Psychiatric illness Personality disorder Alcohol dependence History of self harm Physical illness - debilitating, chronic or terminal conditions Family history Recent adverse events - bereavement
What factors might demonstrate strong suicidal intent?
Planning in advance
Precautions taken to avoid discovery
Dangerous method was used
No help sought after the act
What is the psychiatric illness with the strongest association with suicide?
Anorexia nervosa - 30 fold increase compared to general population
Which groups of patients experiencing a depressive episode should be admitted as a in-patient?
Depressive episodes associated with highly distressing hallucinations, delusions or other psychotic phenomena.
Active suicidal ideation
Lack of motivation leading to extreme self-neglect
Should someone who scores 15 on the BDI-II (Beck’s Depression Inventory II) be prescribed antidepressants?
No. Strictly this person does not fall under the depressed category. They have mild mood disturbance. If this persisted then you may consider treatment.
Should someone who scores 19 on the BDI-II (Beck’s Depression Inventory II) be prescribed antidepressants?
No. Not straight away at least. This person has mild depression and the guidelines recommend that psychological treatment is tried initially.
Should someone who scores 20 on the BDI-II (Beck’s Depression Inventory II) be prescribed antidepressants?
No. Not straight away at least. This person is likely to have mild/moderate depression and the guidelines recommend that psychological treatment is tried initially. If their depression was causing functional impairment then you might consider going straight to pharmacological treatment.
Should someone who scores 27 on the BDI-II (Beck’s Depression Inventory II) be prescribed antidepressants?
Probably. This person is likely to have moderate/severe depression and pharmacological treatment is most likely to be necessary.
What forms of psychological treatment is offered to patients with depression?
CBT Interpersonal therapy (IP) Psychodynamic therapy Family and marital intervention Minfulness-based cognitive therapy
What are the first line antidepressant medications?
SSRI’s. This is because they have less dangerous side effects in overdose.
How long should you wait to review whether SSRI’s are working in someone recently diagnosed with depression?
Review the drug 4-6 weeks after starting. However, patients will probably need to be seen within a week after initial presentation to make sure things have not progressed.
How long should someone be continued on antidepressant medication after a depressive episode?
Continue for 6 months (as long as the medication is found to be working after 4-8 weeks). After this 6 month they could then be very slowly taken off the medication (over at least a year)
If SSRI’s are not found to be helping a depressed patient after 4-8 weeks, what should the clinician do now/
Either choose another SSRI or more commonly start them on mirtazapine.
Name some SSRI’s.
Fluoxetine (Prozac)
Sertraline
Paroxetine
Citalopram
Fluvoxamine
How do SSRI’s work?
Selective presynaptic blockade of serotonin reuptake pumps
What are the side effects of SSRI’s?
Gastrointestinal disturbance (nausea, vomiting, diarrhoea, pain)
Anxiety and agitation
Loss of appetite and weight loss
Insomnia
Sweating
Sexual dysfunction (anorgasmia, delayed ejaculation)
What class of drug is Venlafaxine?
SNRI (selective noradrenaline reuptake inhibitor). Used as an alternative to SSRI’s in depression. They have similar effects.
Why do depressed patients need close monitoring during the first two weeks of their antidepressant course?
Patient’s biological symptoms will be relieved before their psychological symptoms. This means that they will regain energy before their mood and outlook on life improves. This can increase the likelihood and carrying out suicidal thoughts.
What is the mechanism of action of Mirtazapine?
It is a presynaptic alpha-2 blocker which results in increased release of noradrenaline and serotonin from pre-synaptic membrane.
What are the side effects of Mirtazapine?
Drowsiness
Weight gain
Rare cases of neutropenia
Who do we use Venlafaxine (SNRI) for?
Patients with acknowledged treatment resistant depression.
What are the side effects of Venlafaxine (SNRI)?
High doses may exacerbate cardiac arrhythmias and hypertension.
What is the mechanism of action of the tricyclic antidepressants?
Presynaptic blockade of both noradrenaline and serotonin uptake.
As well as blocking noradrenaline and serotonin re-uptake, what other receptors do tricyclic antidepressants block?
Muscarinic
Histaminergic
α-adrenergic
What are the side effects of tricyclic antidepressants as a result of its anti-muscarinic properties?
Dry mouth
Constipation
Urinary retention
Blurred vision
What are the side effects of tricyclic antidepressants as a result of its anti-histaminergic properties?
Weight gain
Sedation
What are the side effects of tricyclic antidepressants as a result of its anti-α-adrenergic properties?
Postural hypotension
What are the cardiotoxic side effects of tricyclic antidepressants?
QT interval prolongation
ST segment elevation
Heart block arrhythmias
Name some tricyclic antidepressants.
Amitriptyline
Lofepramine
Clomipramine
Imipramine
Why are SSRIs preferred over tricylics in the treatment of depression?
SSRIs are not sedating and have fewer anti-muscarinic properties
Which patients with depression might we choose to give tricyclic antidepressants to instead of SSRIs?
Those in whom sedation would be beneficial, eg those experiencing insomnia or psychotic depression patients. SSRIs can make insomnia worse.
What doses of tricyclic antidepressants have been shown to be effective?
125-150mg/day
Below this the patient feels very little benefit and can end up feeling worse on account of the fact that they feel they have resistant depression.
Which group of patients do we use monoamine oxidase inhibitors (MAOIs) in?
Those with atypical depression (hypersomnia, increased appetite, oversensitivity to rejection). However, even in this group they are hardly ever used.
Why are monoamine oxidase inhibitors dangerous?
They lead to a build up of some amines such as tyramine. This can lead to a hypertensive crisis.
Which foods should a patient on monoamine oxidase inhibitors avoid?
Cheese Yeast and protein extract - Marmite, Bovril Chianti wine Beer Soya bean extract
What are the early warning signs of a hypertensive crisis caused by high levels of tyramine as a result of treatment of depression using monoamine oxidase inhibitors?
Throbbing headache
Name some monoamine oxidase inhibitors.
Phenelzine
Tranylcypromine
Isocarboxazid
What is serotonin syndrome?
A collection of symptoms that results from serotonin build up in the CNS, which usually results from an interactions between two drugs (often an SSRI and another antidepressant such as MOAI). Symptoms include restlessness, tremor, shivering, myoclonus, hyperreflexia, confusion, convulsions and possibly death.
How do you treat someone suffering serotonin syndrome?
Stop drug
Monitor and manage hydration and haemodynamics with fluids
Symptomatic relief of agitation with benzodiazepines
Moderate: Cyproheptadine is a 5HT-2A antagonist which is useful in the acute patient.
Severe: need aggressive treatment and intensive care with early sedation, neuromuscular paralysis and ventilatory support.
