Author Contributions: Dr Levin 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: Levin, Robinson-Cohen, de Boer, Liu, Ferrucci, Psaty, Siscovick, Kestenbaum.
Acquisition of data: Levin, Houston, Liu, Kritchesvsky, Cauley, Bandinelli, Hagström, Michaëlsson, Melhus, Wang, Psaty, Siscovick, Kestenbaum.
Analysis and interpretation of data: Levin, Robinson-Cohen, de Boer, Houston, Lohman, Liu, Tanaka, Patel, Hagström, Michaëlsson, Wolf, Siscovick, Kestenbaum.
Drafting of the manuscript: Levin, Robinson-Cohen, Hagström, Kestenbaum.
Critical revision of the manuscript for important intellectual content: Levin, de Boer, Houston, Lohman, Liu, Kritchesvsky, Cauley, Tanaka, Ferrucci, Bandinelli, Patel, Hagström, Michaëlsson, Melhus, Wang, Wolf, Psaty, Siscovick, Kestenbaum.
Statistical analysis: Levin, Robinson-Cohen, Houston, Lohman, Liu, Tanaka, Hagström.
Obtained funding: Houston, Liu, Kritchesvsky, Michaëlsson, Melhus, Psaty, Siscovick, Kestenbaum.
Administrative, technical, or material support: Levin, Robinson-Cohen, Liu, Cauley, Bandinelli, Hagström, Michaëlsson, Wolf, Psaty.
Study supervision: de Boer, Kritchesvsky, Ferrucci, Kestenbaum.
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr de Boer reported receiving research grant funding from Abbott Laboratories. Dr Houston reported pending institutional grant support from the National Institute on Aging, National Institutes of Health; and receiving payment for lectures from the American Society for Nutrition, the Department of Veteran Affairs, and Abbott Nutrition Health Institute. Dr Wang reported serving as a consultant to Diasorin; receiving an investigator-initiated grant from Diasorin; and receiving payment for lectures from Diasorin. Dr Wolf reported serving as a consultant to Abbott, Genzyme, Luitpold, Mitsubishi, Cytochroma, Astellas, and Kai; receiving institutional grants from the National Institutes of Health, Shire, and Amgen; receiving payment for lectures from Abbott, Genzyme, and Shire; and having a pending patent. Dr Psaty reported serving on a data and safety monitoring board for a clinical trial of a device funded by Zoll ZifeCor; and serving on a steering committee for the Yale Open Data Access Project funded by Medtronic. Dr Kestenbaum reported receiving institutional grant support from Amgen. No other authors reported disclosures.
Funding/Support: The Cardiovascular Health Study was supported by contracts HHSN268201200036C, N01-HC-35129, N01-HC-45133, N01-HC-75150, N01-HC-85079 through N01-HC-85086, N01 HC-15103, N01 HC-55222, U01 HL080295, HL087652, and HL096875 from the National Heart, Lung, and Blood Institute; by funding from the National Institute of Neurological Disorders and Stroke; and by grant R01AG027002 from the National Institute on Aging. Handling of DNA and genotyping was supported in part by National Center for Research Resources grant M01RR00069 awarded to the Cedars-Sinai General Clinical Research Center Genotyping Core, and the National Institute of Diabetes and Digestive and Kidney Diseases grant DK063491 awarded to the Southern California Diabetes Endocrinology Research Center. Serum vitamin D measurements in the Cardiovascular Health Study were funded by National Institutes of Health grant R01 HL084443 (Dr Kestenbaum). The Health, Aging, and Body Composition study was supported by National Institute on Aging contracts N01AG62101, N01AG62103, and N01AG62106. Assessment of 25-hydroxyvitamin D levels was funded by National Institute on Aging grant R01-AG029364. The genome-wide association study was funded by National Institute on Aging grant R01-AG032098, and genotyping services were provided by the Center for Inherited Disease Research, which is fully funded through contract HHSN268200782096C from the National Institutes of Health to Johns Hopkins University. The baseline Invecchiare in Chianti study (1998-2000) was supported as a targeted project (ICS110.1/RF97.71) by the Italian Ministry of Health, in part by the US National Institute on Aging contracts 263 MD 9164, 263 MD 821336, N.1-AG-1-1, N.1-AG-1-2111, and N01-AG-5-0002, and in part by the Intramural Research Program of the National Institute on Aging, National Institutes of Health. The Uppsala Longitudinal Study of Adult Men was supported by the Swedish Research Council (2006), Swedish Heart-Lung Foundation, Thuréus Foundation, and Uppsala University.
Role of the Sponsors: None of the funding sources had any role in the design of the study; in the analysis and interpretation of the data; or in the preparation of the manuscript. The National Institutes of Health was involved in the original design and conduct of the Cardiovascular Health Study and the Health, Aging, and Body Composition study, and in the data collection methods and final approval of the manuscript.
Additional Contributions: We thank the other investigators, the staff, and the participants of the Cardiovascular Health Study, the Health, Aging, and Body Composition study, the Invecchiare in Chianti study, and the Uppsala Longitudinal Study of Adult Men for their valuable contributions.