Cognitive behavioural model of pain

Lara Tosunlar, Psychology Research Assistant, Dorset HealthCare NHS Trust
Dr Selwyn Richards, Consultant Rheumatologist, Poole Hospital NHS Trust

In the unfolding years of the 21^st Century, the medical profession aims to increase understanding of the function of pain and accordingly, develop improved treatments. Pain is looked upon nowadays as something to be alleviated at all costs (Bending, 2001). Benson regarded Mind-Body Medicine as an integral part of comprehensive healthcare (Benson, 1975). He likened it to a three-legged stool, using the following metaphor:

“One leg is pharmaceuticals, another is surgery, and the third is what you can do for yourself.
Mind/body medicine is strengthening the third leg, integrated with the other two legs”

Mind-Body Medicine focuses on interactions between the mind, brain, body and behaviour. It also takes into account the influences emotional, mental, social, spiritual and behavioural factors can have on health. The cognitive behavioural model offers a means of understanding the etiological heterogeneity of conditions, such as Fibromyalgia. It suggests conditions may develop as a consequence of a variety of both predisposing and precipitating factors, and that these usually vary from individual to individual. Figure 3 represents a model drawn from Letham’s work in chronic pain (Lethem, Slade, Troup & Bentley, 1983; Philips, 1987) and chronic fatigue syndrome (Surawy, Hackmann, Hawton & Sharpe, 1995).

PREDISPOSING FACTORS Personality Coping style History of illness Childhood stress		PERPETUATING FACTORS Behaviour Increased rest Symptom checking Emotion Depression Frustration Loss of confidence Thoughts Belief in physical illness Fears about symptoms Physical symptoms Pain Fatigue Sleep disturbance
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PRECIPITATING FACTORS Physical illness Trauma Excessive demands Stress, depression

Chronic pain symptoms ought to be viewed as the product of multiple dynamic factors that develop synergistically in combination with certain genetic, psychological, and environmental vulnerabilities (Weisberg & Clavel Jr, 1999). As illustrated above, these factors can be categorised as predisposing, initiating or perpetuating.

In 1983, the fear avoidance model of chronic pain was proposed. This model explains why some individuals continue to experience pain, following an acutely painful episode, even though there may be little evidence of organic pathology (Lethem, 1983; Slade, 1983). Confrontation and avoidance are considered to be the main responses to pain, with most individuals displaying a mixture of the two. For example, following an acutely sprained ankle, initially one may try to avoid further pain and therefore not weight bear. However, as they then recover, most people try and push themselves to confront the pain, by increasing the amount of social and physical activity they do. In contrast, some individuals, driven by fear of further pain leading to increasingly restricted activities despite the resolve of the original injury, exhibit a maladaptive avoidance response.

Initially, pain avoidance decreases exposure to pain. However, in the longer term it often leads to physical de-conditioning, loss of flexibility and muscle strength; an increase in muscle pain and impaired memory recall and verbal fluency. Such changes are often associated with a reduced sense of personal control; increased expectation that exposure will increase pain; reinforcement of invalidity status and exaggerated symptom perception (Lethem, 1983; Slade, 1983; Philips, 1987). Ultimately, avoidance does not lead to a reduction in symptoms and the experience of pain cannot diminish, as it is maintained by the physiological and psychological consequences of fear avoidance.

Several psycho-social factors have been identified as potentially motivating certain individuals towards a maladaptive response. These include personal coping strategies and stressful life events, which undermine adaptive coping strategies. This maladaptive avoidance of pain has been found to be more likely in individuals with depression, those who exhibit a high level of health anxiety or find attention during pain rewarding. Research suggests that individuals who fear symptoms tend to focus on them excessively (Bennett, 2002). In turn, this heightened vigilance can increase avoidance and reinforce illness behaviour, resulting in a decreased pain threshold. This is thought to be the result of the "wind-up phenomenon” (Mendell & Wall, 1965). When pain remains untreated, nerve fibres transmitting the painful impulses to the brain become "trained" to deliver pain signals better. In a similar way that muscles get better at sports with training, the nerves become more effective at sending pain signals to the brain. The intensity of the signals increases over what is necessary to attract an individual’s attention and additionally, the brain becomes more sensitive to the pain. Therefore, despite no deterioration in the actual injury or illness, the pain can feel much worse. It is at this point that pain may be termed “chronic” and pain is no longer a helpful signal of illness.

Developments in pain research have clearly illustrated the need for treatments to combine both physical and psychological components. The cognitive behavioural approach does just that. It aims to improve individuals’ skills at managing and coping with their pain, rather than purely finding a biological solution to the putative pathology. A self-defeating cycle of behaviour and cognitions may be the strongest force in maintaining avoidance behaviour, rather than the pain itself (Asmundson, Norton, & Norton, 1999). Therefore, to actually break this cycle one needs to tackle these cognitions and behaviours, which Philips suggested can be done through repeated graded exposure to avoided behaviours, under low conditions of arousal or stress (Philips, 1987).

Many sufferers believe a medical cure is the only answer to relieve them from their pain. However, cognitive behavioural therapy focuses on returning control back to the sufferer, rather than their doctors. It involves techniques such as cognitive restructuring and coping skills training, which can help patients learn how to pace their daily tasks and activities, including when and how best to relax. By identifying and improving any negative thinking patterns, patients can develop attainable goals for themselves. Physiotherapist run programmes are encouraged to help improve physical fitness, through gentle stretching and exercises (McCracken, Gross, Sorg & Edmands, 1993). For example, chronic back pain classes can help address any fear avoidance sufferers may have; by teaching them that they will not do damage using a graded approach to movement (Crombez, Vervaet, Lysens, Eelen, & Baeyens, 1996; Crombez, Vervaet, Lysens, Baeyens, & Eelen, 1998). Instead, patients should see both a physical and psychological improvement.

In 2003, Turk claimed that “cognitive behavioural treatments should be viewed as important complements to more traditional pharmacological, physical, and surgical interventions”. In an ideal world, an interdisciplinary team of professionals would work together to provide individualised packages for chronic pain sufferers. Limited resources, including limited training and a lack of therapist availability, can reduce the effectiveness of this idealistic approach. However, due to cognitive behavioural therapies’ humanistic emphasis, alongside its practical utility and demonstrable efficacy, it looks to remain an important therapeutic approach despite (Pither, 2001).

“…the Imagination can cause, as well as cure, diseases of the body.
They clearly establish one rule of medical practice which has always appeared
to me highly important. In the best manner possibly a patient ought to be always
inspired with confidence in any remedy which is administered”