Osteoarthritis-associated chronic pain can be disabling, affecting a patient’s quality of life through reduced sleep quality, mood disturbance, interference with social relations, and diminished cognitive function. This has a wider economic impact, with a microsimulation model suggesting that 61,000 productive life years will be lost in 2030 for people aged 45 to 64 owing to arthritis.
Osteoarthritis pain management requires a multidisciplinary, biopsychosocial approach. Nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids are most commonly prescribed for osteoarthritis pain management. However, the use of NSAIDs and opioids may be contraindicated in certain patients with comorbidities or result in unwanted side effects. NSAIDs are associated with increased risk of gastrointestinal bleeding, myocardial infarction, and stroke. Opioids have a high side effect profile with particular concern for dependence. Furthermore, depending on arthritis severity, elective surgery may be required for affected joints. In the UK, joint replacement waiting lists can exceed 52 weeks; hence, a need remains for better therapeutic options for chronic pain because many are not appropriate for long-term use or lack evidence for their effectiveness. Therefore, patients with chronic pain secondary to osteoarthritis require a safe and effective form of analgesia.
The endocannabinoid system (ECS) is a relatively novel physiological mechanism that has been implicated in the control of inflammatory and nociceptive signaling. It is now increasingly being investigated for the development of therapeutics for chronic pain.