Jin Kyun Park1, Se Han Ahn1, Kichul Shin2, Yun Jong Lee3, Yeong Wook Song1, Eun Bong Lee4,5. 1. Department of Internal Medicine, Division of Rheumatology, Seoul National University College of Medicine, 101 Daehak-ro, Jong no-gu, Seoul, 03080, South Korea. 2. Department of Internal Medicine, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, South Korea. 3. Department of Internal Medicine, Division of Rheumatology, Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, South Korea. 4. Department of Internal Medicine, Division of Rheumatology, Seoul National University College of Medicine, 101 Daehak-ro, Jong no-gu, Seoul, 03080, South Korea. leb7616@snu.ac.kr. 5. Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea. leb7616@snu.ac.kr.
Abstract
BACKGROUND:Placebo can have a significant therapeutic effect in patients with hand osteoarthritis (OA). This aim of the study is to identify factors associated with a clinically meaningful placebo response in patients with hand OA. METHODS: This post-hoc analysis of two double-blind, placebo-controlled, randomized trials (RCTs) investigating the efficacy of GCSB-5 or diacerein as treatments for hand OA analyzed the efficacy of a placebo. Clinical and laboratory factors associated with a clinically meaningful response, defined as an improvement in the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) pain score > 10 at 4 weeks relative to baseline, were identified. RESULTS: The mean improvement in the AUSCAN pain score was - 6.0 ± 20.3, with marked variation between 143 hand OA patients (range: - 76.4 to 33.2). A clinically meaningful improvement was observed in 54 (37.8%) patients. Placebo responders had worse AUSCAN pain scores (55.7 ± 19.7 vs. 43.6 ± 21.6, p = 0.001) and a worse AUSCAN stiffness (68.2 ± 20.5 vs. 57.5 ± 24.5, p = 0.008) at baseline than non-responders. Improvements in pain correlated with the baseline pain level (Pearson r = - 427, p < 0.001). Structural joint changes such as tender, swollen, enlarged, or deformed joint counts did not differ between placebo responders and non-responders. In a multivariable analysis, only baseline AUSCAN pain was associated with a clinically meaningful placebo response (OR: 1.054, 95% CI [1.019-1.089], p = 0.002). CONCLUSIONS:High levels of pain at baseline are predictive of a clinically meaningful placebo response in patients with hand OA. Further studies are needed to optimize and utilize the benefit of placebo responses in patients with hand OA.
RCT Entities:
BACKGROUND: Placebo can have a significant therapeutic effect in patients with hand osteoarthritis (OA). This aim of the study is to identify factors associated with a clinically meaningful placebo response in patients with hand OA. METHODS: This post-hoc analysis of two double-blind, placebo-controlled, randomized trials (RCTs) investigating the efficacy of GCSB-5 or diacerein as treatments for hand OA analyzed the efficacy of a placebo. Clinical and laboratory factors associated with a clinically meaningful response, defined as an improvement in the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) pain score > 10 at 4 weeks relative to baseline, were identified. RESULTS: The mean improvement in the AUSCAN pain score was - 6.0 ± 20.3, with marked variation between 143 hand OA patients (range: - 76.4 to 33.2). A clinically meaningful improvement was observed in 54 (37.8%) patients. Placebo responders had worse AUSCAN pain scores (55.7 ± 19.7 vs. 43.6 ± 21.6, p = 0.001) and a worse AUSCAN stiffness (68.2 ± 20.5 vs. 57.5 ± 24.5, p = 0.008) at baseline than non-responders. Improvements in pain correlated with the baseline pain level (Pearson r = - 427, p < 0.001). Structural joint changes such as tender, swollen, enlarged, or deformed joint counts did not differ between placebo responders and non-responders. In a multivariable analysis, only baseline AUSCAN pain was associated with a clinically meaningful placebo response (OR: 1.054, 95% CI [1.019-1.089], p = 0.002). CONCLUSIONS: High levels of pain at baseline are predictive of a clinically meaningful placebo response in patients with hand OA. Further studies are needed to optimize and utilize the benefit of placebo responses in patients with hand OA.
Authors: Marc C Hochberg; Roy D Altman; Karine Toupin April; Maria Benkhalti; Gordon Guyatt; Jessie McGowan; Tanveer Towheed; Vivian Welch; George Wells; Peter Tugwell Journal: Arthritis Care Res (Hoboken) Date: 2012-04 Impact factor: 4.794