Association between metabolic syndrome, radiographic knee osteoarthritis, and intensity of knee pain: results of a national survey

J Clin Endocrinol Metab. 2014 Sep;99(9):3177-83. doi: 10.1210/jc.2014-1043. Epub 2014 Apr 29.


Context: Although osteoarthritis (OA) has been suggested as another component of metabolic syndrome (MetS), weight-independent associations between MetS and knee OA or intensity of arthritic knee pain remain unclear.

Objective: The objective of the study was to evaluate the above associations and suggest possible mechanisms.

Design and setting: This was a cross-sectional study using the fifth Korean National Health and Nutrition Examination Survey (2010).

Participants: A total of 2363 adults (≥50 y of age) who had completed both laboratory examinations and an evaluation for radiographic knee OA participated in the study.

Main outcome and measures: Radiographic knee OA was defined as a Kellgren/Lawrence grade of 2 or greater, and the intensity of arthritic knee pain was assessed using a self-reported numeric rating scale. MetS was diagnosed based on National Cholesterol Education Program-Adult Treatment Panel III criteria, and insulin resistance was evaluated using the homeostasis model assessment-estimated insulin resistance index.

Results: In a multivariable logistic regression analysis, MetS was associated with radiographic knee OA (adjusted odds ratio 1.49; 95% confidence interval 1.23-1.79; P < .001). This association was not changed significantly after further adjusting for homeostasis model assessment-estimated insulin resistance but became nonsignificant after adjusting for weight or body mass index. Age-, sex-, and weight (or body mass index)-adjusted mean score of knee pain was significantly higher in subjects with more components of MetS (P for trend = .010 or .035, respectively).

Conclusions: The association between MetS and radiographic knee OA can be largely explained by an excessive weight but not by insulin resistance, a key pathophysiology of MetS. Because accumulation of MetS components appears to be associated with a higher intensity of knee pain, independently of weight, appropriate treatment for MetS may be helpful for subjects with knee pain.

MeSH terms

  • Aged
  • Arthralgia / diagnostic imaging*
  • Arthralgia / etiology
  • Arthralgia / metabolism*
  • Body Weight
  • Cross-Sectional Studies
  • Female
  • Health Surveys
  • Humans
  • Insulin Resistance
  • Logistic Models
  • Male
  • Metabolic Syndrome / complications
  • Metabolic Syndrome / metabolism*
  • Middle Aged
  • Multivariate Analysis
  • Nutrition Surveys
  • Obesity / etiology
  • Obesity / metabolism
  • Osteoarthritis, Knee / complications
  • Osteoarthritis, Knee / diagnostic imaging*
  • Osteoarthritis, Knee / metabolism*
  • Radiography
  • Republic of Korea