Anxiety disorders Flashcards
Anxiety disorder impact
considerable suffering/impaired functioning
Prevalence: among the most common psychiatric disorders
1 year prevalence: 12-17%
leading cause for seeking mental health services
Normal/clinical anxiety
anticipation of future threat characterized by: - muscle tension - vigilance in preparation for danger - cautious or avoidant behaviours
Normal/clinical fear
Emotional response to real or perceived therat characterized by: - surges of autonomic arousal - thoughts of immediate danger - escape behaviours
Clinical fear and anxiety
excessive in relation to degree of threat
persistent
significant distress/impairment in social and occupational functioning
Features of anxiety/related disorders
Unwanted emotions: panic attacks, chronic hyperarousal, excessive fear
Unwanted thoughts: obsession, excessive worries, intrusive recollections
Unwanted actions: avoidance, escape, distraction, compulsions
Fear of consequences and maladaptive behaviours
Major DSM-5 anxiety disorders and related disorders
Panic disorder Agoraphobia Specific phobia Social anxiety disorder GAD PTSD OCD
Panic attacks
occurs in all anxiety disorders
discrete period of intense fear or discomfort
abrupt onset
peaks w/in 10 minutes
peak intensity lasts an average of 20 minutes
can occur during waking hours/during sleep
>=4 symptoms required to define a panic attack
attacks with fewer than four symptoms = limited symptom panic attacks
Panic attack symptoms
Need four or more, otherwise a "limited symptom" panic attack Palpitations trembling/shaking choking sensations nausea/GI distress chills/hot flushes derealization/depersonalization fear of dying sweating dyspnea chest pain or discomfort paresthesias (numbness, tingling) dizziness/faintness fear of losing control/going crazy
Unexpected/spontaneous panic
characteristic of panic disorder
Expected panic attacks
triggered by a phobic stimulus
Cognitive model of panic attacks
Trigger –> perceived threat –> apprehension –> body sensations –> interpretation of sensations as catastrophic –> threat, etc.
Panic disorder
Recurrent, unexpected panic attacks A month or more of: - persistent concern about further attacks - worry about implications - significant change in behaviour
Agoraphobia
typically a result of panic disorder
Fear of situations in which escape might be difficult or embarrassing if panic-like symptoms occur
feared situations are avoided/endured with dread
Situations commonly feared/avoided in agoraphobia
Travelling being far from home enclosed spaces wide open spaces supermarket line-ups high places being alone
Specific phobia
severe, excessive, persistent fear exposure evokes fear/panic avoidance recognizes fear is unreasonable Not panic disorder Subtypes: animal, natural environment stimuli, situations, blood-injection-injury, others
Specific phobia of dentistry
80% adults apprehensive, 20-30% only visit when in pain
5% visit only in extreme circumstances
Commonly due to traumatic childhood experiences
50% have blood-injury injection phobia
Tx: BDZ prior to visit, but will relapse; CBT with lasting benefits
Social anxiety disorder
Severe, excessive, and persistent fear of: - social intreactions - social performance situations exposure to phobia evokes fear/panic extreme fear of negative evaluation person typically avoids recognizes fear is unreasonable
Generalized anxiety disorder
excessive anxiety and worry difficulty controlling worry thinks worrying is proactive associated symptoms: restless, tension, feeling "on edge", concentration difficulties, irritability, insomnia lasts at least 6 months
OCD
either obsessions or compulsions rule-forming Obsessions: recurrent, persistent thoughts, impulses, or images - intrusive, unwanted - not simply excessive worries
Compulsions:
- repetitive behaviours/mental acts
- aimed at reducing distress or preventing harm
PTSD
exposure to a traumatic event 4 groups of symptoms: 1) re-experiencing 2) avoidance 3) negative changes in mood/cognition 4) hyperarousal
> 1 month
Trauma exposure and PTSD
PTSD is comparatively rare to trauma!
most people are resilient
Trends of anxiety disorders
most: F:M gender ratio range from 2-3:1 OCD: gender ratio 1:1 but earlier onset in males age of onset: - varies with disorder - varies with exposure to stressors - most arise in adolescence - phobias often arise in childhood
Conditioned fear reactions
Classical conditioning
Operant conditioning (avoidance learning)
Role in PTSD, phobias)
Maladaptive fears
prominence role in panic disorder and social anxiety disorder
appear to play a role in other anxiety disorders
Genetics factors - anxiety disorder
No big genes associated with anxiety disorders
Polymorphisms?
Suggestive evidence of the role of genes involved in NT function and neuronal development
Environmental factors - anxiety disorder
Family environment not as important as previously thought, although likely plays some role
extreme family family environments are likely to contribute to risk of developing anxiety disorders
Expressed emotion of family membranes can exacerbate/perpetuate anxiety disorders
environmental experiences outside of family are important: fear conditioning experiences
Neuroanatomy implicated in anxiety disorders
Amygdala HPA axis prefrontal cortex hippocampus frontal-striatal circuits (OCD)
Circuit implicated in anxiety
Sensory thalamus Amygdala Cortex Hippocampus HPA axis all interplay (amygdala/cortex in the middle)
Frontal-striatal circuits implicated in OCD
Thalamus:
Putamen - anterolateral OFC (motor control, response inhibition)
Dorsal caudate - dorsolateral PFC (working memory, executive function) - ACC/ventromedial PFC 9error monitoring, doubting) - nucleus accumbens
Neurotransmitter systems implicated in anxiety disorders
GABA Glutamate Serotonin Noradrenaline Dopamine
Cognitive factors in anxiety disorders
Dysfunctional beliefs
Selective attention to threat
Misinterpretation of threat
Anxiety sensitivity
fear of arousal-related body sensations (fear of fear)
Arises from beliefs about consequences of sensations
- somatic: discomfort vs death
- cognitive: mild vs permanent mental incapacitation
- social: none vs social ostracism/ridicule
Anxiety treatment
1) CBT (exposure therapy, cognitive restructuring), SRI (fluoxetine, sertraline, paroxetine, clomipramine)
Norepinephrine production metabolism
Tyrosine –> L-DOPA –> Dopamine –> DA –> Norepinephrine
Circuits involed in anxiety disorders
Amygdala centered circuit
Cortico-striato-thalamic circuit
Neurochemistry of anxiety
GABA is the key NT
Benzodiazepine: enhances GABA activity in limbic/cortical circuits
Increased NE: symptoms of anxiety
increased 5HT turnover in limbic regions in acute stress
Less evidence for changes in HPA axis
