1. Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan;
2. Center for Clinical Research, School of Medicine, Keio University, Tokyo, Japan;
3. Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan;
4. Division of Biostatistics, School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan;
5. Hino Municipal Hospital, Hino, Japan;
6. Kawasaki Municipal Ida Hospital, Kawasaki, Japan.