Stress, Anxiety and Depression Flashcards
What is the mnemonic for the symptoms of depression?
SIG-E-CAPS Sleep disturbances Interest loss (anhedonia) Guilt (self blame) Energy loss Cognitive/concentration difficulties Appetite changes Psychomotor retardation Suicidal thoughts
How was the Office of National Statistics study on the prevalence of psychiatric morbidity among adults designed?
Two stages - screening interview and more detailed interview involving clinical tests
Large sample size achieved
Symptom questionnaire filled in by patients (potential for bias, but negligible due to large sample size)
What were the major findings of the Office of National Statistics study on the prevalence of psychiatric morbidity among adults?
The people most likely to have a neurotic disorder are women, middle aged, separated or divorced, living alone or a single parent.
People are more likely to have a psychotic disorder if they are separated or divorced, live alone, have low educational qualifications, are of a lower social class.
Most common neurotic symptoms are sleep problems, fatigue, irritability, worry.
Define stress.
Any condition that actually or potentially poses a challenge to the body’s ability to maintain homeostasis.
What are the two types of stress?
Eustress - helpful in preparing to meet challenges, and improves performance
Distress - more chronic, impairs performance
What is a stressor?
Any stimulus that produces a stress response.
What are the two types of stressor?
External - stressors from the physical environment
Internal - self-imposed stressors
What is the graph called that is a physiological response to stressors in an attempt to regain homeostasis?
General adaptation syndrome
What are the 3 phases of stress response?
1) Alarm phase - short term, initial flight or fight response
2) Resistance/adaptation phase - body attempts to cope with long term stress
3) Exhaustion phase - resources are depleted so the body is unable to maintain function and may die
What happens in the alarm phase of stress?
The stressor activates the cerebral cortex which activates the hypothalamus. The hypothalamus activates the sympathetic nervous system which causes the adrenal medulla to release catecholamines (noradrenaline and adrenaline). The catecholamines cause glycogenolysis and vasoconstriction and increased inotropy.
What happens in the resistance/adaptation phase?
There is activation of the HPA axis. The hypothalamus releases corticotropin releasing hormone (CRH) which causes the anterior pituitary gland to release adrenal corticotropic hormone (ACTH) which causes the adrenal cortex to release cortisol.
What are the effects of cortisol release in the resistance/adaptation phase?
Lipolysis and gluconeogenesis from protein (muscle) and glycerol due to depleted glycogen stores.
Immune cells are suppressed.
Aldosterone is released from the adrenal cortex, and increases Na+ reabsorption so that water resorption increases as blood volume and pressure is increased.
What re some of the negative effects of chronic stress?
Can lead to anxiety disorders and depression.
Can lead to hypertension.
Increased gastric acid production can lead to reflux and peptic ulcers.
Immunosuppression can lead to recurrent infections an increased risk of cancer.
Can lead to migraine headaches, asthma attacks, blood glucose fluctuations in diabetics.
Suppression of sex steroid secretion.
When is exhaustion phase entered?
When the body’s resources become so depleted that they can’t sustain the resistance phase. The likely outcome is death.
Name 6 effects of long term exposure to high cortisol levels that may be seen in the exhaustion phase.
Muscle wasting (as protein is broken down for gluconeogenesis) Immunosuppression Peptic ulcers Depression/psychosis Failure of pancreatic beta cells Ageing
How do the hippocampus and amygdala affect the HPA axis?
The hippocampus provides a feedback loop for cortisol levels, if cortisol levels are too high the hippocampus inhibits the hypothalamus so less CRH is produced and less cortisol released.
The amygdala is activates by fear, and when the central nucleus of the amygdala is activated it activates the hypothalamus to increase the HPA axis and SAM system.
What three things does activation of the central nucleus of the amygdala cause?
Activation of the hypothalamus.
Activation of the periaqueductal grey matter (which causes avoidance behaviour).
Activation of the reticular activating system (diffuse modulatory systems) which increases alertness and vigilance.
How do the stress hormones affect memory?
Emotionally salient events are remembered better, and injecting cortisol improves memory. Lesions in the amygdala reduce memory.
What happens to the immune system during the alarm phase and during the resistance phase?
During the alarm phase the immune system is initially upregulated, but during the resistance phase it is suppressed due to cortisol decreasing the numbers of B and T cells.
What is the difference between normal fear response and an anxiety disorder?
A normal fear response is a realistic response to a known threatening stimulus, which is normally short term.
An anxiety disorder is when the fear response occurs in an anticipatory manner and is an unfounded fear, leading to the inappropriate expression of fear which interferes with normal daily activities.
What are 5 types of anxiety disorder?
Generalised anxiety disorder Panic disorder Phobias Obsessive compulsive disorder Post-traumatic stress disorder
What are the symptoms of a panic attack?
Dyspnoea, hyperventilating, palpitations, chest pain, trembling, tingling, can often be mistaken for a heart attack.
What is obsessive compulsive disorder?
Intrusive thoughts (obsessions) which cause anxiety and compulsions (repetitive behaviours) to neutralise the anxiety.
What are the symptoms of PTSD?
Nightmares and flashbacks, difficulty sleeping, detachment, increased arousal, and avoidance of the stimuli associated to the trauma. Hippocampus is reduced in size and amygdala uncontrollably activated.
What is the mechanism of action of benzodiazepines?
Bind to an allosteari cistern on the GABAa receptor to increase affinity of GABA so the effect of GABA is enhanced. This means there is a greater influx of chloride ions and greater hyperpolarisation of the membrane, so action potentials are inhibited.
Which anxiolytic does ethanol have a similar mechanism of action to?
Benzodiazepines
What is schizophrenia?
A relapsing and remitting illness with typical onset on young adulthood.
What is the difference between the positive and negative symptoms of schizophrenia?
Positive symptoms = symptoms that occur during episodes e.g hallucinations, delusions, thought disorder
Negative symptoms = an accumulation of symptoms over time e.g lack of motivation, reduced speech, reduced emotion, social withdrawal