Chronic pain of moderate to severe intensity occurs in 19% of adult Europeans, seriously affecting the quality of their social and working lives. Very few were managed by pain specialists and nearly half received inadequate pain management. Although differences were observed between the 16 countries, we have documented that chronic pain is a major health care problem in Europe that needs to be taken more seriously.

Across Europe and Israel, treatment of cancer pain is suboptimal. Pain and pain relief should be considered integral to the diagnosis and treatment of cancer; management guidelines should be revised to improve pain control in patients with cancer.

Uncertainty about the clinical significance of tolerance to opioid analgesia has important and diverse implications. Although understanding of the characteristics and mechanisms of experimental tolerance has grown, the clinical correlates and ramifications of these findings remain ambiguous to practitioners prescribing long-term opioid therapy to patients for the treatment of malignant and non-malignant pain. In this review I shall discuss clinical aspects of tolerance and the associated phenomena of dependence, withdrawal and addiction to opioids as they apply to the practice of clinicians who manage patients with chronic malignant and non-malignant pain.

Chronic pain affects a large proportion of the population, imposing significant individual distress and a considerable burden on society, yet treatment is not always instituted and/or adequate. Comprehensive multidisciplinary management based on the biopsychosocial model of pain has been shown to be clinically effective and cost-efficient, but is not widely available. A literature review of stakeholder groups revealed many reasons for this, including: i) many patients believe healthcare professionals lack relevant knowledge, and consultations are rushed, ii) general practitioners consider that pain management has a low priority and is under-resourced, iii) pain specialists cite non-adherence to evidence-based treatment, sub-optimal prescribing, and chronic pain not being regarded as a disease in its own right, iv) nurses', pharmacists' and physiotherapists' skills are not fully utilized, and v) psychological therapy is employed infrequently and often too late. Many of the issues relating to physicians could be addressed by improving medical training, both at undergraduate and postgraduate levels - for example, by making pain medicine a compulsory core subject of the undergraduate medical curriculum. This would improve physician/patient communication, increase the use of standardized pain assessment tools, and allow more patients to participate in treatment decisions. Patient care would also benefit from improved training for other multidisciplinary team members; for example, nurses could provide counseling and follow-up support, psychologists offer coping skills training, and physiotherapists have a greater role in rehabilitation. Equally important measures include the widespread adoption of a patient-centered approach, chronic pain being recognized as a disease in its own right, and the development of universal guidelines for managing chronic non-cancer pain. Perhaps the greatest barrier to improvement is lack of political will at both national and international level. Some powerful initiatives and collaborations are currently lobbying policy-making bodies to raise standards and reduce unnecessary pain - it is vital they continue.

Although chronic pain affects around 20% of adults in Europe and the USA, there is substantial evidence that it is inadequately treated. In June 2009, an international group of pain specialists met in Brussels to identify the reasons for this and to achieve consensus on strategies for improving pain management.