Abstract
Background:
Osteoarthritis (OA) is a degenerative joint disease characterized by a complex pathophysiology involving inflammatory biomarkers.
Objectives:
The current study aimed to investigate the correlation between interleukin-6 (IL-6) serum levels and joint space narrowing (JSN) in patients with knee OA.
Design:
A total of 46 patients clinically diagnosed with knee OA were included in this study.
Methods:
Joint space narrowing was measured using radiographic examinations, whereas blood serum levels of IL-6 were quantified using enzyme-linked immunosorbent assay. Statistical analysis was performed to determine the relationship between IL-6 and JSN.
Results:
The average level of IL-6 was 117.61 (67.05) ng/mL, with JSN measurement of 1.76 (1.31) mm. An inverse correlation found between IL-6 levels and the size of the gap joints in patients with knee OA (r = −.298; P = .044).
Conclusion:
An inverse correlation exists between IL-6 levels and joint impairment in knee OA, suggesting that inflammation plays a crucial role in the progression of the disease.
Plain Language Summary
Osteoarthritis is the most common form of arthritis and occurs when the cartilage that cushions the ends of bones in a joint gradually wears away. Inflammation within the joint is now known to accelerate this damage. One substance released during inflammation is a protein called interleukin-6 (IL-6). We aimed to determine whether the level of IL-6 in the blood is associated with the degree of joint space loss in patients with knee osteoarthritis. We recruited 46 men and women who had been diagnosed by their doctor with knee osteoarthritis. Each person had a standard standing x-ray of the affected knee. On these x-rays, we measured the “joint-space width,” the gap between the bones of the thigh and the shin; a narrower gap means more cartilage loss. We also took a small blood sample and measured the level of IL-6. On average, the joint space was about 1.8 mm wide, and the average IL-6 level was 118 ng/mL. When we compared these 2 numbers for each patient, we found that people with higher IL-6 levels tended to have a narrower joint space. In other words, more inflammation was associated with greater cartilage loss. This study suggests that measuring IL-6 in the blood may one day help doctors estimate the rate of progression of knee osteoarthritis. If future research confirms this, IL-6 might become a simple blood test that guides earlier or more targeted treatment to protect the joint.
Get full access to this article
View all access options for this article.