Byung Joo Lee, Seoyon Yang, Sara Kwon, Kyung Hyo Choi, Won Kim
Department  of Rehabilitation Medicine, Daegu Fatima Hospital, Daegu, South Korea.
DOI: 10.2340/16501977-2561

Objective: To investigate the association of metabolic syndrome with the development of knee osteoarthritis.
Design: Cross-sectional nationwide survey study.
Subjects: Data obtained from the 2010–2012 Korea National Health and Nutrition Examination Survey.
Methods: Subjects aged 50 years or older were included. Knee osteoarthritis (≥grade 2 Kellgren-Lawrence) and severe knee osteoarthritis (≥grade 3 Kellgren-Lawrence) were evaluated based on radiological findings. Medical information and demographic data were obtained from survey records. Multivariate regression analysis was performed to investigate the relationship between knee osteoarthritis and metabolic syndrome, and the number of metabolic syndrome components for dose-response relationship evaluation. Analyses were adjusted by age group (model 1) or by age group, education, smoking, alcohol consumption, and physical activity (model 2).
Results: A total of 8,491 subjects (3,684 men and 4,807 women) were included in the study. In women, metabolic syndrome increased the risk of knee osteoarthritis (odds ratio (OR) = 1. 644, p < 0. 001; and OR = 1. 608, p < 0. 001; respectively; for models 1 and 2) and severe knee osteoarthritis (OR = 1. 593, p < 0. 001; and OR = 1. 559, p < 0. 001; respectively; for models 1 and 2). However, in men, knee osteoarthritis and severe knee osteoarthritis were not associated with metabolic syndrome. As the number of metabolic syndrome components increased, knee osteoarthritis and severe knee osteoarthritis generally increased in women, but not in men.
Conclusion: Metabolic syndrome affects the development of knee osteoarthritis and severe knee osteoarthritis in women. In addition, dose-response relationships were observed between metabolic syndrome components and knee osteoarthritis in women, but not in men.

Knee osteoarthritis is a common disorder in old age and is known to be associated with various medical conditions. Metabolic syndrome is a cluster of conditions including hypertension, dyslipidemia, abdominal obesity, and insulin resistance, with a rapidly increasing prevalence. The purpose of our study was to investigate the effect of metabolic syndrome on development of knee osteoarthritis. The result showed that metabolic syndrome affects the development of knee osteoarthritis and severe knee osteoarthritis in women. Additionally, the number of metabolic syndrome components showed additive effect on development of knee osteoarthritis. However, these relationships were not definite in men. Through our study, we were able to connect the impact of metabolic syndrome on knee osteoarthritis. Careful and thorough examination of knee osteoarthritis should be considered in patients complaining of knee pain in case of metabolic syndrome patient. Also, treatment of the components of metabolic syndrome should be emphasized, such case.