[1] Univ Washington, Dept Med, Div Rheumatol, Seattle, WA 98195 USA
[2] Univ Texas Hlth Sci Ctr Houston, McGovern Med Sch, Div Rheumatol & Clin Immunogenet, Houston, TX 77030 USA
[3] Univ Calif San Francisco, San Francisco, CA 94143 USA
[4] Univ Washington, Cardiovasc Hlth Res Unit, Seattle, WA 98195 USA
[5] Univ Washington, Dept Epidemiol, Seattle, WA 98195 USA
[6] Univ Calif San Francisco, Russell Engleman Rheumatol Res Ctr, Dept Med Rheumatol, San Francisco, CA 94143 USA