Pain Management in Osteoarthritis Using the Centrally Acting Analgesics Duloxetine and Pregabalin

Overview

Osteoarthritis is the most common form of arthritis worldwide. Specifically, osteoarthritis of the hands affects millions of people and is a major cause of hand disability and pain. Despite this, there are currently no treatments that delay or halt the development of osteoarthritis. Pain is one of the major symptoms of osteoarthritis and pain management is an important factor to consider in the treatment of this condition. Treatments for pain in osteoarthritis consists of local injections, anti-inflammatory gels or painkillers such as paracetamol. However, most people with osteoarthritis still have pain despite these treatments.

Recent scientific studies have suggested that people with hand osteoarthritis not only feel pain in their hand joints, they also appear to have increased signals in their brain pain processing pathways. At St George's, University of London, the investigators have been conducting studies to find out which brain regions are activated in subjects with hand osteoarthritis. The investigators have found that certain brain regions (thalamus, insula, cingulate and somatosensory cortex) are activated during painful tasks in patients with hand osteoarthritis but not in healthy people. In this study the investigators will establish whether drugs that inhibit pain processing pathways in the brain can help. Patients who are still having pain despite their usual painkillers will be randomly divided into 3 groups: one group will receive a placebo, the other 2 groups will receive one of two different drugs, duloxetine or pregabalin. Participants will be assessed using questionnaires and a brain scan (functional MRI) before and after 13 weeks of taking the tablets. This study will help us to understand the ways in which people feel pain in osteoarthritis. If our trial proves successful,drugs that dampen central pain pathways could be used in combination with local pain-relieving drugs to improve treatment and reduce disability in patients with hand osteoarthritis.