Possible association between circulating CTRP3 and knee osteoarthritis in postmenopausal women.

BACKGROUND: Osteoarthritis (OA) is considered as one of the most common cause of chronic pain and functional disabilities in the elderly.

AIM: To examine serum levels of complement-C1q TNF-related protein 3 (CTRP3) in postmenopausal women with knee OA.

METHODS: A population-based cross-sectional study was performed in women who complained of chronic knee pain. All subjects were followed by clinical and weight-bearing bilateral anteroposterior radiographical examinations. The Kellgren and Lawrence (K&L) score was used for knee OA classification. Two groups of postmenopausal women were chosen to investigate CTRP3 as an OA marker who had the K&L score ≥ 3 as a case group and K&L ≤ 1 as a control group. Serum levels of CTRP3 were measured in two groups.

RESULTS: According to K&L classification, 36 subjects with knee OA and 54 age-matched without or mild OA were selected. After adjusting the obtained data for taking NSAID drugs, the concentration of Ln CTRP3 in serum of patients with OA was lower compared to control group [mean ± SE, (0.39 ± 0.05 ng/ml vs. 0.48 ± 0.03 ng/ml, respectively, p = 0.04)].

DISCUSSION: There is a possible role for CTRP3 as an anti-inflammatory mediator in knee OA in postmenopausal women.

CONCLUSIONS: Our results indicate an association between CTRP3 and knee OA. However, a much more robust study is required to draw that circulating CTRP3 could be a clinical marker for osteoarthritis.