Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study

Abstract

Objectives. In some rheumatoid arthritis (RA) patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC). Methods. 38 women with active RA (DAS28 > 2.6) and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p < 0.01) and pain tolerance (p < 0.01) than HC. The mean temporal summation- (TS-) index in RA patients was 0.98 (SEM: 0.09) and 0.71 (SEM: 0.04) in HC (p < 0.01). Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies.

New Pressure Algometry Device for the Quantification of Acupuncture Induced Pain Relief

“…However more than one in ten RA patients that are shown to be in remission by the Disease Activity Score 28 (DAS28) still report clinically significant pain levels. The fact is that pain persists despite the absence of signs of inflammation [2].…”

“…Over 90% of patients with RA have involvement of the wrist and small joints of the hand, including the knuckles and the middle joints of the fingers involving destructive polyarthritis of the synovium. Pain is one of the major symptoms impacting an RA patient's quality of life and leads in around 30% of the patients to limitations in daily life activities [1][2][3]. About 60 to 90% of patients with RA dissatisfied with conventional treatments side effects tend to use complementary and alternative medicine, including acupuncture [3][4][5][6].…”

“…Pain is inherently subjective and pain measurement in patients with RA relies primarily on self-reports or by simple palpation of the joints [2].…”

“…These symptoms can occur spontaneously, can be evoked by gentle stimulation of the joint when it is moved within its normal working range or can be indicative of changes in their central pain modulation which then becomes a primary cause of pain, possibly outlasting the inflammatory activity [2,18].…”

“…However more than one in ten RA patients that are shown to be in remission by the Disease Activity Score 28 (DAS28) still report clinically significant pain levels. The fact is that pain persists despite the absence of signs of inflammation [2].The magnitude of symptoms may not necessarily correlate with the severity of the underlying disease and symptoms may persist even when disease exacerbations have apparently settled.Pain and tenderness associated with the disease are not only present in directly affected joints but also in adjacent, apparently normal, tissues. These symptoms can occur spontaneously, can be evoked by gentle stimulation of the joint when it is moved within its normal working range or can be indicative of changes in their central pain modulation which then becomes a primary cause of pain, possibly outlasting the inflammatory activity [2,18].…”