Fibulin-3 fragments are prognostic biomarkers of osteoarthritis incidence in overweight and obese women

Objective: To determine the association between three fibulin-3 peptides and the incidence of radiographic and clinical knee osteoarthritis (OA). Design: Women between 50 and 60 years, with a BMI >= 27 kg/m(2), free of knee OA, were recruited. Using binary logistic regression, the association between baseline concentration of serum fibulin (Fib) 3-1, Fib3-2 and Fib3-3 and incidence of clinical and radiographic knee OA after 30 months of follow-up was evaluated. Results: Baseline and follow-up measurements were available for 241 women with a mean age of 55.9 +/- 3.2 years and mean BMI of 31.7 +/- 3.6 kg/m(2). None of the concentrations of the three Fib3 epitopes were associated with the incidence of medial or lateral joint space narrowing (JSN) >= 1.0 mm or the incidence of Kellgren & Lawrence (K&L) grade >= 2 after 30 months. All three Fib3 epitopes were associated with the incidence of the clinical and radiographic ACR-criteria and Fib3-1 and Fib3-3 also with chronic pain at follow-up. When adjusted for the other Fib3 peptide concentrations, only Fib3-1 was significantly associated to the incidence of the American College of Rheumatology (ACR)-criteria (OR 3.2 [1.2-8.7]) and chronic pain at follow-up (OR 3.0 [1.2-7.7]). Conclusions: Baseline fibulin-3 concentrations are associated with the incidence of clinical knee OA among middle-aged overweight and obese women. Therewith, they meet the criteria of a prognostic biomarker according to the BIPED biomarker classification for OA. Further validation of the fibulin-3 epitopes seems warranted in order to better distinguish subgroups of individuals at increased risk for knee OA development. (C) 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.