The association between leptin, interleukin-6, and hip radiographic osteoarthritis in older people: a cross-sectional study

Arthritis Res Ther. 2010;12(3):R95. doi: 10.1186/ar3022. Epub 2010 May 19.


Introduction: The associations between leptin, interleukin (IL)-6, and hip radiographic osteoarthritis (OA) have not been reported, and their roles in obesity-related hip OA are unclear. The aim of this study was to describe the associations between leptin, IL-6, and hip radiographic osteoarthritis (ROA) in older adults.

Methods: A cross-sectional sample of 193 randomly selected subjects (mean age, 63 years; range, 52 to 78 years; 48% female subjects) were studied. Hip ROA, including joint-space narrowing (JSN) and osteophytes, was determined by anteroposterior radiograph. Serum levels of leptin and interleukin (IL)-6 were measured with radioimmunoassay. Fat mass was measured with dual-energy x-ray absorptiometry (DXA). Body mass index (BMI) and waist-to-hip ratio (WHR) were calculated.

Results: In multivariable analysis, hip JSN was associated with serum levels of leptin in the whole sample (beta=0.046 per microg/L, P=0.024 for superior; beta=0.068 per microg/L, P=0.004 for axial compartment) and IL-6 only in females (beta=0.241 per pg/ml, P=0.002 for superior; beta=0.239 per pg/ml, P=0.001 for axial compartment). The positive associations between body-composition measures (BMI, WHR, percentage total fat mass, and percentage trunk fat mass) and hip JSN in women became nonsignificant after adjustment for leptin but not for IL-6. No significant associations were found between leptin, IL-6, and the presence or severity of osteophytes.

Conclusions: This study suggests that metabolic and inflammatory mechanisms may play a role in the etiology of hip OA and that the associations between body composition and hip JSN are mediated by leptin, particularly in women.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Biomarkers / blood
  • Body Composition / physiology
  • Body Mass Index
  • Cross-Sectional Studies
  • Female
  • Hip Joint / diagnostic imaging
  • Humans
  • Interleukin-6 / blood*
  • Leptin / blood*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Osteoarthritis, Hip / blood*
  • Osteoarthritis, Hip / diagnostic imaging*
  • Osteoarthritis, Hip / physiopathology
  • Radiography
  • Severity of Illness Index*
  • Sex Characteristics


  • Biomarkers
  • Interleukin-6
  • Leptin