Marked Independent Relationship between Circulating Interleukin-6 Concentrations and Endothelial Activation in Rheumatoid Arthritis

Table 4

Independent associations between interleukin-6 concentrations and endothelial activation score in subgroups.

Subgroups	Partial 𝑅	𝑃
Population grouping
Black (𝑛=112)	0.416	<0.0001
White (𝑛=105)	0.378	0.0002
Age
≤55, y (𝑛=90)	0.366	0.002
>55, y (𝑛=127)	0.415	<0.0001
Sex
Women (𝑛=183)	0.382	<0.0001
Men (𝑛=34)	0.418	0.05
Smoking
Never (𝑛=150)	0.349	<0.0001
Ever (𝑛=66)	0.441	0.001
Missing data (𝑛=1)
BMI, kg/m^2
≤29.9 (𝑛=147)	0.354	<0.0001
>29.9 (𝑛=65)	0.506	0.0005
Missing data (𝑛=5)
Hypertension
No (𝑛=82)	0.265	0.03
Yes (𝑛=135)	0.452	<0.0001
Chol-HDL chol ratio > 4
No (𝑛=173)	0.365	<0.0001
Yes (𝑛=39)	0.422	0.03
Missing data (𝑛=5)
RA duration, y
≤10 (𝑛=100)	0.327	0.003
>10 (𝑛=116)	0.437	<0.0001
Missing data (𝑛=1)
Rheumatoid factor
Negative (𝑛=48)	0.311	0.08
Positive (𝑛=168)	0.406	<0.0001
Missing data (𝑛=1)
DAS28
≤2.6 (𝑛=41)	0.268	0.05
>2.6 (𝑛=176)	0.443	<0.0001
Deformed joints
≤6 (𝑛=123)	0.335	0.002
>6 (𝑛=119)	0.439	<0.0001
Missing data (𝑛=1)

Age, sex, and cardiovascular risk factors were adjusted in each model as in Table 2. BMI: body mass index; HDL: high-density lipoprotein; RA: rheumatoid arthritis; DAS28: disease activity score in 28 joints (values of ≤2.6 and >2.6 indicate the presence of disease remission or mild disease activity and moderate or high disease activity, resp.).