Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Differences in Muscle Strength and Pain Thresholds between Postmenopausal Women with and without RA.
Thoors, Ulrika, H. Opava, Christina, Glenmark, Birgitta, Kosek, Eva, E. Lundberg, Ingrid, Friden, Cecilia
Muscle weakness, in particular loss of muscle mass, pain and tenderness are common symptoms in rheumatoid arthritis (RA). This seems to be the case even when inflammation is well controlled and may result in increasing disability with increasing age. Increased pain and increased loss of muscle mass is also found among healthy women at the time of menopause. The aim of our study was to examine differences in muscle strength and pain thresholds between postmenopausal women with and without RA.
Ten postmenopausal women with early (<2 years) RA (median age 57.5, median BMI 24) and ten healthy women (median age 58.5, median BMI 25) were recruited for the study. All women were independent in daily living, had passed menopause and did not use hormone replacement therapy. The median DAS 28 score was 2.7 (range 1.34.0) and the median HAQ score was 0.57 (range 01) in the RA group.
Measurements of isokinetic muscle strength in knee flexors and extensors, grip strength, timed standing, pressure pain thresholds (PPT), supra threshold pressure pain rated as 4/10 and 7/10 respectively on a Borg CR-10 scale, and segmental and plurisegmental endogenous pain inhibitory mechanism during muscle contraction were assessed in all participants.
No significant difference in knee extensor strength was detected between the women with RA and the healthy ones. Participants with RA were significantly weaker in the knee flexors (p=0.01) and in grip strength (p=0.007), and they were slower in the timed standing (p=0.05). Compared to the healthy women, those with RA had increased sensitivity to threshold pain (p=0.007) and to supra threshold pressure pain at both levels measured (p=0.001 and p=0.004 respectively). PPTs increased at the contracting muscle as well as at a distant resting muscle during standardized static contractions in both groups alike.
Our results indicate that previously noted difference in muscular strength between women with and without RA is present in early disease, in patients with low disease activity and seems to remain even after menopause. Further, the women with RA have generalized allodynia and hyperalgesia, but no dysfunction of segmental and plurisegmental pain inhibitory mechanisms. The normal function of endogenous pain inhibitory mechanisms despite chronic pain in women with RA might contribute to the good effects of physical activity in this group of patients.
To cite this abstract, please use the following information:
Thoors, Ulrika, H. Opava, Christina, Glenmark, Birgitta, Kosek, Eva, E. Lundberg, Ingrid, Friden, Cecilia; Differences in Muscle Strength and Pain Thresholds between Postmenopausal Women with and without RA. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :2245