The psychology of chronic pain

Why should chronic pain matter to psychologists?

Chronic pain, the experience of pain for longer than three months, is a common and costly experience for the Australian community. Based on our present population, we could expect to see around five million Australians living with chronic pain by 2050, with costs incurred exceeding the current best estimate of $AUD34 billion annually (Access Economics, 2007). The importance of the problem is illustrated by the Global Burden of Disease study, which estimated that low back pain alone was the leading worldwide cause of years lived with disability in 2010 (Vos et al., 2012). Australian epidemiological data suggests that, for a significant minority, chronic pain interferes with their daily activities (11 per cent of males and 13.5 per cent of females) and is associated with being unemployed or receiving disability benefits (Blyth et al., 2001; Nicholas, 2007). Although the severity of the impact of chronic pain on quality of life is very variable, the associated disability is not just due directly to the physical limitations imposed by the pain, but is also due to commonly associated mental health conditions which occur at disproportionately high rates among this group, including depression and increased risk of suicidal ideation (Dersh, Polatin, & Gatchel, 2002; Nicholas, 2007).

Despite the prevalence and costs of chronic pain to both the individuals living with it and the wider community, access to effective, specialist services is limited. An Australian study conducted in 2010 identified long waiting times, particularly for public patients who waited on average 138 days from receipt of referral to initial assessment, indicating that demand outstrips supply (Hogg, Gibson, Helou, DeGabriele, & Farrell, 2012).

Specialist pain services in Australia come in different levels, from the primarily biomedical in approach to sophisticated interdisciplinary teams offering a wide range of interventions based on a biopsychosocial approach to the condition. Particularly in the latter, psychologists are key to the delivery of psychologically based pain-management programs, and there is widespread recognition of the centrality of role of the psychologist in these services (Burke, Denson, Mathias, & Hogg, 2015). However, recognition of the contribution persistent pain makes to return to function after workplace injuries, for example, has meant that the demand for access to psychologists who can enhance functional outcomes is markedly on the rise. Consequently, the size and scope of the psychological workforce participating in the prevention and management of chronic pain is now wider and more varied than ever.

Historically, chronic pain has been viewed as a medical problem requiring a medical solution. However, the effectiveness of the most commonly used medical and surgical interventions for pain continue to fall short of the mark, with only limited effectiveness (Turk, Wilson, & Cahana, 2011). Where patients failed to respond to such treatments, their medically unexplained pain problems were commonly relegated to a psychiatric diagnosis. Such practices lag behind the contemporary understanding of the role of psychological factors in pain, a door which was opened by the Gate Control Theory which was in part authored by psychologist Ronald Melzack (Melzack & Wall, 1965). This provided a basis from which a plethora of developments in our understanding sprang, and from that, a burgeoning of psychological treatments to offer hope to those affected. In particular, it revealed psychological factors as important potential mediators between tissue injury and both disability and distress. This has been exploited by both psychological researchers and practitioners ever since, elevating psychological treatments from a position of last resort to the linchpin of both chronic pain prevention and treatment that we see today.

What does psychology have to contribute?

The development of psychological interventions for chronic pain emerged in the 1960s, and the evolution of treatment approaches has reflected trends in psychological treatments of other disorders. Pain was framed within a biopsychosocial model, and treatments developed that targeted firstly behavioural contingencies, and increasingly cognition, coping, and more recently central neurophysiological mechanisms (Gatchel, Peng, Peters, Fuchs, & Turk, 2007). Most commonly applied in practice and well-established in the literature are cognitive behavioural interventions, and variations upon them, that have a large evidence base to support their relative effectiveness among a broad range of both primary and secondary chronic pain problems experienced across the lifespan. The task now has become to better understand the effective components of these treatments and how best to target them to the individual’s risk factors, as well as identifying and managing those who appear not to respond to standard approaches (Nicholas et al., 2013; Nicholson Perry, Nicholas, & Middleton, 2010; Williams, Eccleston, & Morley, 2012).

Important questions remain about whether variations on the standard approaches, such as acceptance and commitment therapy programs, offer differential benefits for particular subgroups of the chronic pain population, or whether the addition of specific components might confer additional advantages over outcomes of standard interventions. Although the weight of evidence for these approaches is not sufficient to recommend their use as the first line of treatment, continued research about the contribution they may make to the field is important.

While the effectiveness of management of chronic pain has evolved rapidly, a significant number of people remain disabled by their pain despite access to these treatments. Attention has turned to preventing a short-term pain problem, known as acute or sub-acute pain depending on the time frame, from turning into a chronic pain problem that impacts upon the individual’s functioning. The application of this psychological knowledge to primary prevention of chronic pain in our community and management of acute and sub-acute pain in the workplace has the potential to make a significant impact on the overall burden of pain in our communities and is one of the most exciting developments in the field of recent times.

Psychological factors have become increasingly well-recognised as risk factors for the development of disabling chronic pain (Nicholas, Linton, Watson, & Main, 2011) and this knowledge has been used for secondary prevention of pain-related disability in a variety of ways, particularly in the area of workers compensation. The importance of community understanding about low back pain and its effective management was illustrated by work conducted in Victoria. A population-based intervention using a television advertising campaign was sufficient to significantly change beliefs that were sustained over three years (Buchbinder & Jolley, 2005). Knowledge of these risk factors has also been used to identify workers at high risk of pain-related disability, tailor early-intervention programs that are embedded in the workplace, and target both the injured workers and their supervisors to reduce the risk of sick leave and other negative consequences (Linton, Boersma, Traczyk, Shaw, & Nicholas, 2016). These community and workplace interventions highlight the important potential contribution of psychology to the prevention of the negative consequences of painful conditions, such as reduced function at work and in other valuable life roles, and the need for psychologists working in these settings to be well-versed in the evidence in order to effectively implement interventions at these levels.

As the field matures, there are a number of challenges ahead for the provision of effective psychological interventions in this area. This includes identifying subgroups where specific mechanisms may be responsible for the transition from sub-acute to disabling chronic pain, such as attentional biases, some of which have very exciting implications for managing the recovery from injury of vulnerable individuals (Todd et al., 2015). As recognition of the need for psychological intervention to help manage the explosion of chronic pain-related disability evolves, the risk is that demand will outstrip the supply of psychologists who are both competent and confident to deliver these interventions. Advocacy for more effective management of pain by organisations such as Painaustralia, implementing the recommendations of the National Pain Strategy (National Pain Summit Initiative, 2010), as well as changes to funding and support structures for affected individuals (such as the National Disability Insurance Scheme) are likely to fuel demand and expand the range of psychologists for whom chronic pain is a relevant problem.

Gazing into the crystal ball

So, what are the implications for psychologists? Certainly, we can no longer see the role of psychologists in chronic pain as something undertaken by a few specialist members of our professional community. Many practising psychologists currently active in Australia will have had only cursory training in this field as part of their academic studies or continuing professional development. Consequently, we might all benefit from conducting an audit both of our skills and knowledge, as well as our practices, to ensure that the needs of people with chronic pain are being responded to adequately. This includes having a low threshold for screening for the presence of chronic pain in those who might be considered high risk, including injured workers, those with medical problems, those with a trauma history and those presenting with psychological issues that are commonly comorbid, such as depression. Where managing clients with chronic pain exceeds our competencies, we may need to identify appropriately trained and experienced other psychologists and health professionals to whom such people could be referred. We need to ensure that training programs of all types leading to registration adequately prepare psychologists for the relevant work that they may do in this area.

Equally, all currently registered psychologists should consider whether they are sensitive to the presence of chronic pain as a contributor to the issues they encounter, and whether they are sufficiently familiar with the appropriate evidence-based psychological interventions so they can deliver them or be in a position to provide referrals to others who can (Sharpe, Nicholas, & Nicholson Perry, 2015). A minimum level of competence is required for all psychologists to be able to screen for chronic pain as a contributory factor to a presentation, and to assess basic psychological constructs as part of that, such as pain catastrophising and self-efficacy. This can be done with standardised tools adopted by specialist pain services (see Key assessment domains and measures).

We need to continue to develop and make use of resources that support the evidence-based practice of psychologists with people with chronic pain. This includes projects such as the Chronic Pain Toolkit for Clinicians developed by the NSW Pain Management Network, which provides evidence-based resources to assist clinicians undertaking assessment and management of pain, including providing a number of well-established psychometric tools and resources based on best practice approaches to the condition (www.aci.health.nsw.gov.au/chronic-pain). Novel innovations, such as the provision of online cognitive behavioural pain-management programs, offer an opportunity to provide access to these evidence-based treatments either independently or with the support of a psychologist. While these are an emerging model of care, there is a burgeoning body of literature to support their efficacy and investments by government and other bodies to enhance access to them (Dear et al., 2015; Dear et al., 2013). This is perhaps particularly relevant for those for whom access to traditional pain-management services, often based in metropolitan areas and with long waiting lists, is an issue due to physical impairments.

Funding models that allow access to a psychologist outside contexts such as workers compensation and compulsory third-party motor vehicle accident schemes are also essential, as currently limitations to funding for treatment by psychologists through Medicare are not well targeted to permit treatment of those with chronic pain.

Psychology and psychologists have made significant contributions to the prevention and management of chronic pain in recent decades. Ensuring the effective implementation of this knowledge relies, however, on psychologists developing a level of competence in the area of chronic pain to enable early identification as well as further assessment and management (including referral) of chronic pain in a client as required. In addition, being prepared to engage with the issue by influencing policy and procedures in the workplace and more broadly in the community, rather than necessarily solely in the context of a consulting room, is of equal importance.

The first author can be contacted at [email protected]