1. Department of Rheumatology Research, Clinical Research Center for Allergy and Rheumatology, National Hospital Organization Sagamihara National Hospital , Kanagawa, Japan
2. Department of Rheumatology, National Hospital Organization Fukuoka National Hospital , Fukuoka, Japan
3. Department of Rheumatology, Tokyo Medical University Hospital , Tokyo, Japan
4. Department of Rheumatology, National Hospital Organization Tokyo National Hospital , Tokyo, Japan