L19 Mood Disorders Flashcards
Symptoms of depressive disorders
Symptoms occur continually for more than 2 weeks
Core symptoms:
- low mood
- lack of energy
- lack of enjoyment and interest
Other symptoms:
- feelings of worthlessness, guilt and being a burden
- biological symptoms - loss of appetite, drinking less fluids and lack of sleep
- severe = psychotic symptoms
Difference between adjustment and depression
Depression:
- Symptoms are gradual and continuous fro more than 2 weeks
- lack of interest
- loss of appetite and weight loss
- lack of energy
- low self esteem, guilt and blame
- sleep disturbance with EMW
Adjustment:
- acute onset after event with limited time period
- symptoms fluctuate
- preoccupied with event
- reduced or increased appetite
- feelings of anger and frustration
Features of mania
- elated mood
- increased energy
- pressure of speech
- decreased need for sleep
- flight of ideas
- Social inhibition is lost
- attention not sustained
- inflated self esteem that is grandiose
- psychotic symptoms
Bipolar diagnosis
- At least 2 episodes of a mood disorder at least 1 being mania or hypomania
- normally starts between 15-19 yrs old
- fluctuate between mania and depression
- episodes can be years apart
Bipolar I
Discrete episodes of mania only or mania and depression
Bipolar II
Discrete episodes of hypomania or hypomania and depression
- more likely for severe depression
Euthymia
Normal stable mental state or mood
Subsyndromal depression
Symptoms of depression aren’t as severe a enough to be diagnosed with depression
Differential diagnosis for depression
Hypothyroidism Lack of vit B12 Anaemia Chronic disease - renal, CVS, liver failure Substance misuse Hypoactive delirium
Differential diagnosis for mania
Iatrogenic - steroid use in cancer Hyperthyroidism Delirium Infection - encephalitis, syphilis, HIV Head injury Intoxication with stimulants
Brain structures involved in mood disorders
Limbic system - amygdala and hippocampus
Frontal lobe
Basal ganglia
How do brain structures regulate mood disorders
Functional circuits connect the limbic system, basal ganglia and frontal lobe which affect:
- cognitive processed thoughts
- sympathetic and parasympathetic output
- motor systems
Limbic system
Network of neurones in the medial portions of the cortex Comprised of: - amygdala - feelings - hippocampus - memories - hypothalamus - homeostasis - pineal gland - melatonin regulates sleep - corpus callosum - anterior thalamic nuclei
Functions of the limbic system
Emotion
Motivation
Memory
Changes to limbic system in unipolar depression
Decreased hippocampal volume
Decreased cerebral blood flow and metabolism in the amygdala
Limbic system changes bipolar disorder
Increased amygdala activation and volume in mania
Decreased volume and activation in anterior paralimbic cortices e.g ventral prefrontal cortex, insular cortex
Prefrontal cortex
Ventromedial- Generation, processing and expression of emotion
Orbital prefrontal cortex - emotional responses via connections with the amygdala
Frontal lobe function
2/3rds of the total cortex
- motor function
- Broca’s area
- social and moral reasoning
- attention
- memory
- old
Frontal lobe changes in depression
Decreased activity and blood flow in the prefrontal cortex
Decreased volume of the orbitofrontal prefrontal cortex
Basal ganglia functions
Motor functions - direct and indirect pathway
Psychological:
- emotion
- cognition
- behaviour
Possible basal ganglia changes in depression
Decreased basal ganglia volume
Reduced activation between the amygdala, striatum and prefrontal cortex
Overall contribution of brain circuits to depression
Prefrontal cortex - slow thoughts, altered emotional processing and executive dysfunction
Amygdala - abnormal emotional processing
Basal ganglia - impaired incentive behaviour and psychomotor changes
Neurotransmitters in autoimmune disorders
Monoamines:
- serotonin
- noradrenaline
Serotonin
Produced in the brain stem in the raphe nuclei
Transported to cortical areas in the brain and limbic system
Role in:
- sleep
- impulse control
- appetite
- mood
Role of serotonin in depression
Low serotonin
Therefore give: - SSRI - monoamine oxidases inhibitors - tricyclic antidepressants > increase serotonin in the synaptic cleft
- 5HIAA a metabolite of serotonin is low in CSF of patients with depression that have attempted suicide
- tryptophan - precursor of serotonin is depleted in depression
Noradrenaline
Produced in the locus coeruleus in the pons
Projects to the cortex and limbic system
Function:
- mood
- behaviour - arousal and attention
- fight to flight
- memory function
Role of noradrenaline in mood depression
Decreased in depression
Treatment:
- SNRI - serotonin and noradrenaline reuptake inhibitor
- NARI
- TCA
Treatment of depression
Biological:
- SSRI - prosac
- SNRI and TCA
- if life threatening depression or resistance against medication, electroconvulsive therapy is used twice a week
Psychological- CBT
Social - help with isolation (elderly), social stressors e.g housing
Treatment of mania
Biological:
- antipsychotics - dopamine antagonists
- mood stabilisers - lithium and sodium valproate
Psychological:
- psychoeducation about triggers and relapse
- as unlikely to engage with CBT
Social:
- treat in safe place that decreases risk to self and others
- tackle implications of mania e.g. over spending, STI and pregnancy
Why is it hard to treat mania
People feel good therefore are less likely to take medication
When is sodium valproate contraindicated
In women of child baring age
Unless strict pregnancy prevention schemes are implemented
Treatment of bipolar depression
Biological:
- antidepressants with mood stabiliser (lithium) to prevent mania
- ECT
Psychological:
- CBT
- psychoeducation
Social:
- isolation in elderly
- social stressors
- employment - shift work as tired
- involvement and education to family
