Exam Literature Overview
Cognitive-Behavioral Interventions
Suzanne M.J.C. Derksen
Msc Health and Medical Psychology
Leiden University
2020-2021
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,Additional Literature Week 2
The cognitive behavioural model of medically unexplained symptoms: A theoretical and
empirical review - Deary, Chalder, and Sharpe
Introduction Three ways ‘medically unexplained symptoms (MUS)’ is used:
1. To refer to the occurrence of symptoms in the absence of
obvious pathology
2. To refer to individual clinical syndromes such as chronic
fatigue syndrome (CFS) and irritable bowel syndrome (IBS)
3. To refer to a subset of the DSM-IV somatoform disorders
category
This review uses MUS to refer to itself as a term (“medically
unexplained symptoms”), to individual syndromes and to some of
the subcategories of somatoform disorder.
The model Historically, the classical CBT model of emotional distress as
proposed by Beck distinguished between its developmental
predispositions and precipitants, and its perpetuating cognitive,
behavioural, affective and physiological factors (Beck, 1976).
⇒ The CBT model of MUS retains this general structure and its
“three Ps”: predisposing, precipitating and perpetuating factors.
Any CBT model is a vicious circle, the hypothesis that a self
perpetuating interaction between different domains maintains
symptoms, distress and disability.
The CBT models of MUS, IBS and CFS propose a model of
perpetuation that is, to borrow a term from systems theory and
cell biology, autopoietic.
Autopoiesis: the process whereby an organization produces itself.
An autopoietic organization is an autonomous and
self-maintaining unity. The components, through their
interaction, generate recursively the same network of processes
which produced them.
Components: Genetics and early experience
Predisposing
factors There is some evidence for a genetic influence in the
development of both unexplained fatigue and somatisation
however this could simply reflect the expression of an inheritable
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, predisposition to general distress.
Neuroticism and somatopsychic distress
Neuroticism (N) as a personality trait refers to a stable life long
tendency to experience negative affect.
High N has been demonstrated in functional dysphonia, in
Irritable Bowel Syndrome and in general MUS.
Components: The CBT model proposes that cognitive and behavioural factors
Perpetuating interact with physical factors to produce symptoms. There has
factors been much promising work in recent years investigating
mechanisms other than physical pathology that might be partly
responsible for perpetuating MUS.
Sensitisation refers to the tendency to have a heightened
response to stimuli because of prior experience of them.
A specific sensitisation mechanism – long term potentiation (LTP)
– in humans has been studied. LTP can be induced in pain
pathways by prior experience of pain or noxious stimulation
which lowers the threshold for future stimulation.
LTP could be linked to sensitisation processes in IBS and in
fatigue patients.
The HPA-axis and sensitisation
Physical and emotional stress in humans causes a hormonal
cascade beginning in the hypothalamus, passing to the pituitary
and ending with the increased production of cortisol from the
adrenal cortex. Within this system – the hypothalamus pituitary
adrenal axis (HPA axis) – both positive and negative feedback
loops exist to regulate the body's response to acute and chronic
stress. The HPA axis alters energy metabolism, influences
immune functioning and affects both energy and mood with, for
instance, high levels of cortisol being consistently found in major
depression.
Cleare (2004) has reviewed the evidence for HPA axis involvement
in CFS. Whilst there is evidence for an increased sensitivity to the
negative feedback effect in the HPA axis, and for reduced ACTH
and cortisol responses, there is no obvious HPA axis dysfunction.
Attention - Cognitive activation and behavioral inhibition
The biological findings in patients with MUS are highly varied and
do not yet present a consistent and coherent picture. Whilst there
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, is some evidence of increased autonomic arousal and of delayed
recovery of the stress response, these findings vary between
conditions and between different phases of the same condition.
Evidence for attentional processes
The attentional models point to individual differences in
attentional biases with respect to threatening stimuli as a factor
in MUS.
→ Individuals who either perceived themselves as more
vulnerable or the symptom as more threatening were more likely
to pay attention to the symptoms.
→ Overall, whilst attention seems to be important it has been
hard to isolate this process from attributions, unhelpful illness
beliefs, medical uncertainty and other factors which may serve to
focus attention onto symptoms.
From attention to attribution and beliefs
Researchers suggested a Symptom Perception Model of MUS, in
which negative affectivity, selective attention and somatic
attributions are hypothesised as the key factors determining the
experience of common physical symptoms.
There is a broad consensus that making organic illness
attributions, lack of normalising attributions and high estimates
of personal vulnerability predict increased symptom experience
and illness behaviours such as expression of symptoms and
seeking treatment, whereas psychological or mixed somatic and
psychological attributions predict better symptom outcomes.
Qualitative approach to attribution: viewpoint of illness narratives
— how do people explain symptoms to themselves? Multifaceted
attributions: individuals from different cultures making sense of
their symptoms through complex narratives that involve social,
emotional and physical processes.
→ A key finding from this work is that any narrative is better than
none; those who could not make sense of their symptoms in
some way were the most distressed, and reported the least
benefit from the interview process.
Response to illness
Several authors have observed that it is not just the illness, but
one's response to it that matters.
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