A novel inflammatory biomarker, GlycA, associates with disease activity in rheumatoid arthritis and cardio-metabolic risk in BMI-matched controls

Table 2 GlycA relationships with disease activity, inflammatory, and adiposity measures

	GlycA		Fisher transformation
	RA	Controls	P value
Markers of disease activity and inflammation
Disability (HAQ-DI)	0.28	NA	NA
Pain (VAS) (mm)	0.08	0.11	0.91
Disease activity (DAS_ESR-28)	0.54 ^‡	NA	NA
ESR (mm/hour)	0.71 ^‡	0.24	0.02
hsCRP (mg/l)	0.73 ^‡	0.32 ^†	0.01
IL-1β (pg/ml)	0.19	0.08	0.62
IL-6 (pg/ml)	0.28 ^†	−0.14	0.05
IL-8 (pg/ml)	−0.20	−0.07	0.56
IL-18 (pg/ml)	−0.14	0.41 ^†	0.01
TNFα (pg/ml)	−0.09	−0.14	0.82
Measures of adiposity and insulin resistance
BMI (kg/m²)	0.16	0.38 ^†	0.28
Waist circumference (cm)	0.12	0.38 ^†	0.22
Total abdominal adiposity (cm²)	0.31 ^†	0.36 ^†	0.80
Abdominal subcutaneous adiposity (cm²)	0.26	0.34 ^†	0.70
Abdominal visceral adiposity (cm²)	0.25	0.21	0.86
Thigh subcutaneous adiposity (cm²)	0.21	0.55 ^‡	0.08
Thigh intermuscular adiposity (cm²)	0.06	0.18	0.60
Thigh muscle density (Hu)	−0.33 ^†	−0.14	0.40
Fasting insulin (mU/l)	0.18	0.37 ^†	0.38
Fasting glucose (mg/dl)	0.35 ^†	0.16	0.36
HOMA	0.17	0.39 ^†	0.30
IS index (×10^–5.min⁻¹/(pmol/l))	−0.26	−0.34 ^†	0.70
Acute insulin response (pmol/l)	0.05	0.48 ^†	0.04

Data presented as Spearman correlation coefficients (r)
^†0.005 < P <0.05, ^‡ P ≤0.005
BMI body mass index, DAS _ESR -28 Disease Activity Score with 28-joint count using the erythrocyte sedimentation rate, ESR erythrocyte sedimentation rate, HAQ-DI Health Assessment Questionnaire–Disability Index, HOMA homeostasis model assessment, hsCRP high-sensitivity C-reactive protein, IL interleukin, IS insulin sensitivity, RA rheumatoid arthritis, TNFα tumor necrosis factor alpha, VAS visual analog scale, NA not applicable
bold text represents significant associations