Serum Interleukin-15 Levels Are Associated with Severity of Pain in Patients with Knee Osteoarthritis

Table 1

Clinical characteristics and serum IL-15 levels.

	Controls	OA patients	KL grade 2	KL grade 3	KL grade 4
	(𝑛=106)	Total (𝑛=226)	(𝑛=99)	(𝑛=74)	(𝑛=53)
Age (years)	63.61±11.15	64.01±9.49	64.64±10.31	63.86±8.53	63.06±9.27
Female (𝑛, %)	61, 57.55%	139, 61.50%	64, 64.65%	45, 60.81%	30, 56.60%
BMI (Kg/mm^2)	22.43±2.28	23.10±2.04	23.31±2.24	22.94±1.78	22.96±1.99
IL-15 (pg/mL)	2.17 (1.53–3.37)	6.04 (4.82–8.96)	6.35 (5.09–10.09)	6.00 (4.35–8.47)	5.85 (4.10–7.38)
WOMAC-pain scores		11 (8–18)	10 (9–14)	11 (6–18)	14 (9–18)

All values are expressed as the mean value ± SD or 𝑛 (%). OA: osteoarthritis; KL: Kellgren-Lawrence; BMI: body mass index; IL-15: interleukin-15. *𝑃<0.01 compared with controls.