Factors Associated with Knee Pain with Different Grades of Knee Osteoarthritis among Korean Adults Aged 50 Years or More

Background Discordance between knee pain and radiologic osteoarthritis is well‐known. This study was to investigate factors associated with knee pain with different grades of knee osteoarthritis among Korean adults aged 50 years or more. Methods Total 5,978 Korean aged 50 years or more who underwent the radiographs of the knees were analyzed from Korean National Nutrition and Health Examination Survey conducted in 2010‐11. Radiographs of the knees were scored for osteoarthritis using the Kellgren‐Lawrence scale. Multivariate logistic regression analysis adjusting for sociodemographic factors, lifestyle factors, comorbidity and health status was used for analysis. Results The prevalence of knee pain was higher in female compared to that of male (P<0.001), and increased as increasing severity of radiologic knee osteoarthritis. Female was associated with increased risk of knee pain in all of Kellgren‐Lawrence degrees. In most of Kellgren‐Lawrence degrees, depression was associated with increased risk of knee pain, and those with high school diploma or higher were associated with decreased risk of knee pain. A few factors (age, body mass index, and no alcohol drinking) were also associated with increased risk of knee pain for particular grades of radiographic knee osteoarthritis. Conclusions Knee pain increased as increasing severity of radiologic knee osteoarthritis. Although there were differences of risk factors associated with knee pain with different grades of knee osteoarthritis, female, depression were associated with increased of knee pain, and those with high school diploma or higher were associated with decreased risk of knee pain in most of Kellgren‐Lawrence degrees.