Association of dietary magnesium intake with radiographic knee osteoarthritis: Results from a population-based study
Article first published online: 27 AUG 2012
Copyright © 2012 by the American College of Rheumatology
Arthritis Care & Research
Volume 64, Issue 9, pages 1306–1311, September 2012
How to Cite
Qin, B., Shi, X., Samai, P. S., Renner, J. B., Jordan, J. M. and He, K. (2012), Association of dietary magnesium intake with radiographic knee osteoarthritis: Results from a population-based study. Arthritis Care Res, 64: 1306–1311. doi: 10.1002/acr.21708
- Issue published online: 27 AUG 2012
- Article first published online: 27 AUG 2012
- Accepted manuscript online: 17 APR 2012 11:23AM EST
- Manuscript Accepted: 9 APR 2012
- Manuscript Received: 20 SEP 2011
- CDC/Association of Schools of Public Health. Grant Numbers: S043, S1733, S3486
- National Institute of Arthritis
- Musculoskeletal and Skin Diseases Multipurpose Arthritis Musculoskeletal Disease Center. Grant Numbers: 5-P60-AR30701, P60-AR49465, T32-AR007416
- John A. Hartford Foundation Centers of Excellence in Geriatric Medicine fellowship grant
- University of North Carolina Clinical Nutrition Research Center grant. Grant Number: DK56350
- National Heart, Lung, and Blood Institute. Grant Number: R01HL081572
- Sanofi-Aventis/University of North Carolina Global Nutrition Scholarship
To examine the cross-sectional association between dietary magnesium intake and radiographic knee osteoarthritis (OA) among African American and white men and women.
The presence of radiographic knee OA was examined among participants from the Johnston County Osteoarthritis Project and was defined as a Kellgren/Lawrence grade of at least 2 in at least 1 knee. The Block Food Frequency Questionnaire was used to assess magnesium intake. Effect modifiers were explored by testing interactions of magnesium intake and selected factors based on previous studies. The multivariable logistic regression model with standard energy adjustment method was used to estimate the relationship between magnesium intake and radiographic knee OA.
The prevalence of knee OA was 36.27% among the 2,112 participants. The relationship between magnesium intake and radiographic knee OA was found to be modified by race (P for interaction = 0.03). An inverse threshold association was observed among whites. Compared to participants in the lowest quintile, the relative odds of radiographic knee OA were cut by one-half for participants in the second quintile of magnesium intake (odds ratio 0.52, 95% confidence interval 0.34–0.79); further magnesium intake did not provide further benefits (P for trend = 0.51). A statistically significant association was not observed among African Americans.
A modest inverse threshold association was found between dietary magnesium intake and knee OA in whites, but not in African Americans. Further studies are needed to confirm these results and to elucidate the possible mechanisms of action for the racial modification.