Author Contributions: Dr Wolbink had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Bartelds, Krieckaert, Nurmohamed, Lems, Dijkmans, Aarden, Wolbink.
Acquisition of data: Bartelds, Krieckaert, Nurmohamed, Wolbink.
Analysis and interpretation of data: Bartelds, Krieckaert, Nurmohamed, van Schouwenburg, Twisk, Aarden, Wolbink.
Drafting of the manuscript: Bartelds, Krieckaert, Nurmohamed, Lems, Wolbink.
Critical revision of the manuscript for important intellectual content: Bartelds, Krieckaert, Nurmohamed, van Schouwenburg, Lems, Twisk, Dijkmans, Aarden, Wolbink.
Statistical analysis: Bartelds, Twisk, Wolbink.
Obtained funding: Wolbink.
Administrative, technical, or material support: Bartelds, Krieckaert, Nurmohamed, van Schouwenburg, Dijkmans, Aarden, Wolbink.
Study supervision: Nurmohamed, Lems, Twisk, Dijkmans, Aarden, Wolbink.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Nurmohamed reports having received consultancy fees from Abbott, Roche, Pfizer, MSD, UCB, BMS, and Wyeth; payment for lectures from Abbott, Roche, and Pfizer; and research grants from Abbott, Roche, and Pfizer. Dr Lems reports having received honoraria for lectures from Abbott, Roche, and Schering-Plough. Dr Dijkmans reports having received research grants from Schering-Plough, Abbott, and Wyeth. Dr Wolbink reports having received a research grant from Wyeth Pharmaceuticals and honoraria for lectures from Amgen and Pfizer. No other disclosures were reported.
Funding/Support: Funding was provided by Abbott Laboratories and Wyeth Pharmaceuticals.
Role of the Sponsor: Abbott Laboratories and Wyeth Pharmaceuticals had no involvement in the study design; in the collection, analysis, and interpretation of data; in the writing of the manuscript; or in the decision to submit the manuscript for publication.
Additional Contributions: We are grateful to the Clinical Research Bureau of Reade, formerly the Jan van Breemen Institute, which receives support from the Dutch Arthritis Foundation, for help in the practical aspects of the cohort study. We thank the following research nurses for performing clinical assessments: Marga Kammeijer-Rippen, Anne-Marie Abrahams, Astrid Twisk, and Martine Kos, Department of Rheumatology, Jan van Breemen Research Institute; and for preparation and performing the assays, we thank Henk de Vrieze, MSc, and Kim van Houten, MSc, Sanquin Research; and Margret de Koning, MSc, Department of the Clinical Laboratory, Jan van Breemen Research Institute. None of the individuals listed in this acknowledgment received compensation for their work in association with this study.