17 - Anxiety Disorders Flashcards
What is the difference between neurology and psychiatry?
What is the difference between organic and functional psychosis?
Functional: Neurotic or psychotic disorders e.g depression and schizophrenia, where the behaviour is changing but there is no change in the brain compared to a healthy individual
Organic: brain changes causing disease such as dementia, epilepsy, where there are behavioural changes as well as physical changes
Genetics and environmental inputs
What is neurosis and psychosis?
Neurosis: disorders of the motor systems with physical signs and pathology e.g Parkinson’s and epilepsy
Psychosis: presence of hallucinations or delusions
What are the different approaches of treating mental illnesses?
- Psychopharmacotherapy
- Psychotherapy/Social approaches to sort environmental factors
Why are psychiatric diseases called disorders?
Based on recognisable clusters of symptoms and behaviours
What are the arguments for and against classification in psychiatry?
For:
- Allows doctors to communicate with each other and patients
- Understand implications of diagnosis e.g prognosis and treat
- For research
Against:
- Labels deviant behaviour as illness
- Individuals do not fit neatly into categories
- Stigma
What is the definition of anxiety and what is it’s physiological function?
- The stress response (causing a feeling of anxiety) enables us to escape from potentially dangerous situations
- Anxiety is a feeling of worry or unease about something with an uncertain outcome, often when you percieve a threat
What are some symptoms of anxiety?
Pathological stress response
How is the stress response mediated?
By the limbic system communicating with the cortex and the hypothalamus (limbichypothalamopituitary system)
What is the limbic system made up of and what are the functions of each of these parts?
Hippocampus: receives inputs from many parts of the cortex and processes their emotional content. Projects to the thalamus and back to the cortex, and the hypothalamus causing autonomic features of emotional response
Amygdala: involved in behavioural and autonomic emotional responses and sits near tip of hippocampus. outputs to cortex, brainstem and hypothalamus
(Prefrontal cortex): modulation of emotional responses (suppresses anxiety) and allows perception of emotion
(Cingulate Gyrus)
What is the endocrine and neural elements of the stress response?
Neural: NA from adrenal medulla etc
Endocrine: limbic system acts on hypothalamus to stimulate secretion of stress hormones
Release of cortisol from the adrenal cortex is part of the ‘chronic’ stress response
- Endocrine response causes increased metabollism, immune suppression and inhibition of allergic/inflammatry processes
What is the general adaptation syndrome that occurs during prolonged exposure to stressors?
1. Alarm reaction: sympathetic activation, NA and cortisol release
2. Resistance: adrenaline starts to wear off so chronic stress response and chronic cortisol production
3. Exhaustion: chronic side effects of chronic cortisol production start to show when you cannot escape a stressor
Issue with stress response is when you cannot escape stressor!! Anxiety disorders can go through these stages as they may have psychological stressors e.g social embarrassment
What are some of the different classifications of anxiety disorders?
- Social: anxiety about being in social situations
- Specific phobias: e.g spiders
- Generalised anxiety disorder: persistent anxiety about a variety of things
- Panic disorder: recurrent, unexpected panic attacks (severe episodes of acute stress response)
- OCD
- PTSD
What is the pathophysiology of anxiety disorders?
- Unclear as ambigious findings in brain activation pattern studies
- GABA (inhibitory neurotransmitter) levels appear to be low in some anxiety disorders (maybe explaining action of benzodiazepines)
- Increasing serotonin levels can help treat anxiety disorders
(mechanism unclear, but hippocampus may be involved)
How are anxiety disorders treated?
- SSRIs (take few months to kick in)
- CBT
- Pregabalin (GABA analogue)
- Benzodiazepenes: not long term as addictive withdrawal. work by enhancing GABA binding
What is the epidemiology of OCD?
- Affects males and females equally
- 75% have started by age 30
- 1 on 50 will suffer at some point in lives
- 1/3 of cases start between 10-15 years
What is OCD characterised by?
Obsessions: a thought that persists and dominants an individuals thinking despire the awareness that their thoughts are completely without purpose. Often leads to a lot of anxiety and guilt as the intrusive thoughts are often unpleasant
Compulsions: motor act resulting from an obsession. acting out a compulsion may relieve the anxiety provoked by its associated obsession, but frequently carrying out the compulsion is also unpleasant. patient knows they are excessive and trys to resist but can’t
How is OCD diagnosed?
- Obsessions and or compulsions must be present on most days for at least 2 weeks
Obsessions and compulsions have the following features:
- Originate in the mind of the patient
- Repetitive and unpleasant
- Acknowledged as excessive or unreasonable
- Patient tries to resist, but at least one obsession/compulsion is
unsuccessfully resisted
What is the pathophysiology of OCD?
Unclear but some hypotheses:
- Reentry circuits in basal ganglia
- Reduced serotonin
- PANDAS
- Altered activity in a range of cortical areas (e.g cingulate cortex)
What is PANDAS?
Pediatric Autoimmune Neuropsychiatric Disorders
- Sudden onset of OCD symptoms or tics after infection with Group A Beta Haemolytic Strep in 3-12 years
- Cross-reactivity with certain streptococcal antigens and the basal ganglia causing dramatic onset behavioural and psychiatric problems
- Responds to treatment with antibiotics and normal OCD treatment
How do we treat OCD?
- SSRIs +/- antipsychotics like clomipramine (higher dose longer treatment than depressions)
- Deep brain stimulation (if other methods fail)
- CBT (exposure response prevention)
- Family support and groups
What are the features of post traumatic stress disorder?
- Can occur within six months following an exceptionally severe traumatic event (e.g. rape, battlefield trauma)
- Repetitive, intrusive recollection or re-enactment of the event in memories, daytime imagery, or dreams
- Emotional detachment, numbing of feeling, and avoidance of stimuli that might arouse recollection of the trauma
What is the pathophysiology of PTSD?
- Unclear
- Evidence of amygdala hyperactivity causing exaggerated behavioural responses to percieved threat
- Low levels of cortisol (which cortisol normal inhibits traumatic memory retrieveal)
How do we treat PTSD?
- Same medical treatment as other anxiety disorders
- CBT
- EMDR
