Blood draws were performed at the time of the baseline visit following an overnight fast. Blood samples were allowed to clot at room temperature for 30 minutes, and serum was separated by centrifugation at 1,500 g at 4 °C for 20 minutes. Aliquots were stored at −80° C in the MOST repository. For the determination of lipid profiles, matched case-control samples (N=994) were shipped overnight on dry ice to the Cardiovascular Nutrition Laboratory at the Jean Mayer USDA Human Nutrition Research Center of Aging at Tufts University. Serum total cholesterol and HDL concentrations were measured on an AU400e automated analyzer (Beckman Coulter, Brea, CA; intra-assay CV< 3%; inter-assay CV <4%) using enzymatic reagents (Beckman-Coulter). LDL concentration was calculated using the Friedewald equation (19 (link)) except when triglycerides were above 400mg/dl. For those samples, a direct LDL method was used (AU400e automated analyzer, Beckman Coulter, Brea, CA; intra-assay CV< 2.4%; inter-assay CV <3.6%).
Schwager J.L., Nevitt M.C., Torner J., Lewis C.E., Matthan N.R., Wang N., Sun X., Lichtenstein A.H, & Felson D. (2022). Is there an association of serum low density lipoprotein, high density lipoprotein or total cholesterol with development of knee osteoarthritis?. Arthritis care & research, 74(2), 274-280.
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