RT Journal Article SR Electronic T1 Relationship between Serum Magnesium Concentration and Radiographic Knee Osteoarthritis JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 1231 OP 1236 DO 10.3899/jrheum.141414 VO 42 IS 7 A1 Zeng, Chao A1 Wei, Jie A1 Li, Hui A1 Yang, Tuo A1 Zhang, Fang-Jie A1 Pan, Ding A1 Xiao, Yong-Bing A1 Yang, Tu-Bao A1 Lei, Guang-Hua YR 2015 UL http://www.jrheum.org/content/42/7/1231.abstract AB Objective. To establish whether there is a relationship between serum magnesium (Mg) concentration and radiographic knee osteoarthritis (OA).Methods. There were 2855 subjects in this cross-sectional study. Serum Mg concentration was measured using the chemiluminescence method. Radiographic OA of the knee was defined as changes consistent with Kellgren-Lawrence (K-L) grade 2 on at least 1 side. Mg concentration was classified into 1 of 4 quartiles: ≤ 0.87, 0.88–0.91, 0.92–0.96, or ≥ 0.97 mmol/l. Multivariable logistic analysis was used to test the association between serum Mg and radiographic knee OA after adjustment for potentially confounding factors. The OR with 95% CI for the association between radiographic knee OA and serum Mg concentration were calculated for each quartile. The quartile with the lowest value was regarded as the reference category.Results. Significant association between serum Mg concentration and radiographic knee OA was observed in the model after adjustment for age, sex, and body mass index, as well as in the multivariable model. The multivariable-adjusted OR (95% CI) for radiographic knee OA in the second, third, and fourth serum Mg concentration quartiles were 0.90 (95% CI 0.71–1.13), 0.92 (95% CI 0.73–1.16), and 0.72 (95% CI 0.57–0.92), respectively, compared with the lowest (first) quartile. A clear trend (p for trend was 0.01) was observed. The relative odds of radiographic knee OA was decreased by 0.72 times in the fourth serum Mg quartile compared with the lowest quartile.Conclusion. Serum Mg concentration may have an inverse relationship with radiographic OA of the knee.