Hong-Wei Tam1, Chyong-Mei Chen2, Pui-Ying Leong3,4, Chao-Hsi Chen1, Yuan-Chao Li1, Yu-Hsun Wang5, Li-Chi Lin3,4,6, Jeng-Yuan Chiou7, James Cheng-Chung Wei3,4,8. 1. School of Medicine, Chung Shan Medical University, Tai Chung, Taiwan. 2. Institute of Public Health, School of Medicine, National Yang-Ming University, Taipei, Taiwan. 3. Division of Allergy, Immunology and Rheumatology, Chung Shan Medical University Hospital, Tai Chung, Taiwan. 4. Institute of Medicine, Chung Shan Medical University Hospital, Tai Chung, Taiwan. 5. Department of Medical Research, Chung Shan Medical University Hospital, Tai Chung, Taiwan. 6. Department of Statistics, Oklahoma State University, Stillwater, OK, USA. 7. School of Health Policy and Management, Chung Shan Medical University, Tai Chung, Taiwan. 8. Institute of Integrative Medicine, China Medical University, Tai Chung, Taiwan.
Abstract
AIM: To investigate the effects of hydroxychloroquine, sulfasalazine and methotrexate on ischemic stroke in patients with rheumatoid arthritis (RA). METHODS: This population-based retrospective cohort study included 7904 RA patients and 15 808 non-RA patients between 2000 and 2010. All of the participants were sampled from the National Health Insurance Research Database (NHIRD) of Taiwan. Using univariate analyses, these two groups of patients were compared to evaluate the differences in disease-modifying anti-rheumatic drugs usage and demographic variables. Cox proportional hazard models and Schoenfeld residuals test were performed to estimate the hazard ratios for ischemic stroke and proportional hazard assumptions of these drugs, respectively. RESULTS: The mean age of participants was about 53 years old, and about 70% of RA patients were women. The hazard ratio for ischemic stroke was 1.21 (95% CI: 1.10-1.34; P < 0.01) in the case group compared with the control group, and this significant difference persisted throughout the 10-year period. With respect to RA patients, while hydroxychloroquine showed an insignificant protective effect on ischemic stroke, sulfasalazine and methotrexate were found out to have inconsistent effects during these 10 years. The proportional hazard assumption test of methotrexate at > 0.5 defined daily dose (8.75 mg/week) was violated at a significant level after adjustment (P = 0.0002). CONCLUSIONS: At a dosage of > 0.5 defined daily dose, short-term methotrexate might decrease ischemic stroke risk in RA patients, while hydroxychloroquine and sulfasalazine were neutral.
AIM: To investigate the effects of hydroxychloroquine, sulfasalazine and methotrexate on ischemic stroke in patients with rheumatoid arthritis (RA). METHODS: This population-based retrospective cohort study included 7904 RApatients and 15 808 non-RApatients between 2000 and 2010. All of the participants were sampled from the National Health Insurance Research Database (NHIRD) of Taiwan. Using univariate analyses, these two groups of patients were compared to evaluate the differences in disease-modifying anti-rheumatic drugs usage and demographic variables. Cox proportional hazard models and Schoenfeld residuals test were performed to estimate the hazard ratios for ischemic stroke and proportional hazard assumptions of these drugs, respectively. RESULTS: The mean age of participants was about 53 years old, and about 70% of RApatients were women. The hazard ratio for ischemic stroke was 1.21 (95% CI: 1.10-1.34; P < 0.01) in the case group compared with the control group, and this significant difference persisted throughout the 10-year period. With respect to RApatients, while hydroxychloroquine showed an insignificant protective effect on ischemic stroke, sulfasalazine and methotrexate were found out to have inconsistent effects during these 10 years. The proportional hazard assumption test of methotrexate at > 0.5 defined daily dose (8.75 mg/week) was violated at a significant level after adjustment (P = 0.0002). CONCLUSIONS: At a dosage of > 0.5 defined daily dose, short-term methotrexate might decrease ischemic stroke risk in RApatients, while hydroxychloroquine and sulfasalazine were neutral.