Limited educational attainment and radiographic and symptomatic knee osteoarthritis: a cross-sectional analysis using data from the Johnston County (North Carolina) Osteoarthritis Project
1 Thurston Arthritis Research Center, Department of Medicine, 3300 Thurston Building, CB # 7280, University of North Carolina, Chapel Hill, NC 27599-7330, USA
2 Thurston Arthritis Research Center, Department of Orthopaedics, 3300 Thurston Building, CB # 7280, University of North Carolina, Chapel Hill, NC 27599-7330, USA
3 Thurston Arthritis Research Center, Department of Social Medicine, 3300 Thurston Building, CB # 7280, University of North Carolina, Chapel Hill, NC 27599-7330, USA
4 Duke University Medical Center, DUMC 3918, Durham, NC 27710, USA
5 Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
6 Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, 3106E McGavran-Greenberg Hall, CB #7420, Chapel Hill, NC 27599-7420, USA
7 Division of Environmental Health, Keck School of Medicine of the University of Southern California, 1975 Zonal Avenue, KAM 500, Los Angeles, CA 90089-9034, USA
8 Department of Radiology, University of North Carolina, 509 Old Infirmary Bldg, Campus Box 7510, Chapel Hill, NC 27599, USA
Arthritis Research & Therapy 2010, 12:R46 doi:10.1186/ar2956Published: 18 March 2010
Applying a cross-sectional analysis to a sample of 2,627 African-American and Caucasian adults aged ≥ 45 years from the Johnston County Osteoarthritis Project, we studied the association between educational attainment and prevalence of radiographic knee osteoarthritis and symptomatic knee osteoarthritis.
Age- and race-adjusted associations between education and osteoarthritis outcomes were assessed by gender-stratified logistic regression models, with additional models adjusting for body mass index, knee injury, smoking, alcohol use, and occupational factors.
In an analysis of all participants, low educational attainment (<12 years) was associated with higher prevalence of four knee osteoarthritis outcomes (unilateral and bilateral radiographic and symptomatic osteoarthritis). Women with low educational attainment had 50% higher odds of having radiographic knee osteoarthritis and 65% higher odds of symptomatic knee osteoarthritis compared with those with higher educational attainment (≥ 12 years), by using fully adjusted models. In the subset of postmenopausal women, these associations tended to be weaker but little affected by adjustment for hormone replacement therapy. Men with low educational attainment had 85% higher odds of having symptomatic knee osteoarthritis by using fully adjusted models, but the association with radiographic knee osteoarthritis was explained by age.
After adjustment for known risk factors, educational attainment, as an indicator of socioeconomic status, is associated with symptomatic knee osteoarthritis in both men and women and with radiographic knee osteoarthritis in women.