An Osteoprotegerin Gene Polymorphism Is Associated with an Increased Risk of Hip Fracture in Japanese Patients with Rheumatoid Arthritis: Results from the IORRA Observational Cohort Study

• Shinji Yoshida ,

  Contributed equally to this work with: Shinji Yoshida, Katsunori Ikari

  Affiliations Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan, Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan

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• Katsunori Ikari ,

  Contributed equally to this work with: Shinji Yoshida, Katsunori Ikari

  * E-mail: kikari@ior.twmu.ac.jp

  Affiliation Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan

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• Takefumi Furuya,

  Affiliation Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan

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• Yoshiaki Toyama,

  Affiliation Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan

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• Atsuo Taniguchi,

  Affiliation Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan

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• Hisashi Yamanaka,

  Affiliation Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan

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• Shigeki Momohara

  Affiliation Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan

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