Pain is one of the most common reasons for an individual to consult their primary care physician, with one in five adults in Europe estimated to be affected by chronic pain. However, one of the challenges of managing pain in the primary care setting is that it is poorly assessed and reported. Chronic pain has a major negative impact on quality of life, workforce participation and productivity, and healthcare expenditure. Indeed, US statistics estimate that total annual costs associated with chronic pain are $US560–635 billion whereas, across Europe, data indicate that 3–10% of gross domestic product is spent on national healthcare and socioeconomic costs associated with chronic pain.
Pain has been defined by various groups over the years, often categorized according to the terms “acute” and “chronic”. A common definition of acute pain is “the normal, predicted physiological response to an adverse chemical, thermal or mechanical stimulus … associated with surgery, thermal or trauma, and acute illness”.
Traditionally, chronic pain has been defined by the International Association for the Study of Pain (IASP) as “pain without apparent biological value that has persisted beyond the normal tissue healing time (usually about 3 months)”. It is widely accepted that, unlike acute pain, chronic pain has no protective function. Recently, an updated definition of pain has been proposed: “Pain is a distressing experience associated with actual or potential tissue damage with sensory, emotional, cognitive, and social components”.
