Plasma levels of interleukin-1 receptor antagonist (IL1Ra) predict radiographic progression of symptomatic knee osteoarthritis.

Journal Article (Journal Article)

OBJECTIVE: Pro- and anti-inflammatory mediators, such as IL-1β and IL1Ra, are produced by joint tissues in osteoarthritis (OA), where they may contribute to pathogenesis. We examined whether inflammatory events occurring within joints are reflected in plasma of patients with symptomatic knee osteoarthritis (SKOA). DESIGN: 111 SKOA subjects with medial disease completed a 24-month prospective study of clinical and radiographic progression, with clinical assessment and specimen collection at 6-month intervals. The plasma biochemical marker IL1Ra was assessed at baseline and 18 months; other plasma biochemical markers were assessed only at 18 months, including IL-1β, TNFα, VEGF, IL-6, IL-6Rα, IL-17A, IL-17A/F, IL-17F, CRP, sTNF-RII, and MMP-2. RESULTS: In cross-sectional studies, WOMAC (total, pain, function) and plasma IL1Ra were modestly associated with radiographic severity after adjustment for age, gender and body mass index (BMI). In addition, elevation of plasma IL1Ra predicted joint space narrowing (JSN) at 24 months. BMI did associate with progression in some but not all analyses. Causal graph analysis indicated a positive association of IL1Ra with JSN; an interaction between IL1Ra and BMI suggested either that BMI influences IL1Ra or that a hidden confounder influences both BMI and IL1Ra. Other protein biomarkers examined in this study did not associate with radiographic progression or severity. CONCLUSIONS: Plasma levels of IL1Ra were modestly associated with the severity and progression of SKOA in a causal fashion, independent of other risk factors. The findings may be useful in the search for prognostic biomarkers and development of disease-modifying OA drugs.

Full Text

Duke Authors

Cited Authors

  • Attur, M; Statnikov, A; Samuels, J; Li, Z; Alekseyenko, AV; Greenberg, JD; Krasnokutsky, S; Rybak, L; Lu, QA; Todd, J; Zhou, H; Jordan, JM; Kraus, VB; Aliferis, CF; Abramson, SB

Published Date

  • November 2015

Published In

Volume / Issue

  • 23 / 11

Start / End Page

  • 1915 - 1924

PubMed ID

  • 26521737

Pubmed Central ID

  • 26521737

Electronic International Standard Serial Number (EISSN)

  • 1522-9653

Digital Object Identifier (DOI)

  • 10.1016/j.joca.2015.08.006


  • eng

Conference Location

  • England