Table 1. Comparisons of demographics, risk factors, and atherosclerosis measurements in patients and control subjects.
| SLE patients (N = 281) median (IQR) | Controls (N = 281) median (IQR) | p-value | Corrected p-value h | |
|---|---|---|---|---|
| Age (years) | 49(36–59) | 49(36–59) | - | |
| Female sex % | 93 | 93 | - | |
| Disease duration (years) | 13(6–23) | - | - | |
| Age at disease onset (years) | 29(22–40) | - | - | |
| Traditional risk factors and laboratory tests | ||||
| Current smoking % | 19 | 14 | 0.16 | |
| Ever smoking % | 54 | 47 | 0.12 | |
| Systolic blood pressure (mm Hg) | 118(110–132) | 119(110–131) | 0.91 | |
| Diastolic blood pressure (mm Hg) | 73(68–80) | 75(70–83) | 0.0059 | 0.30 |
| Hypertension % b | 46 | 20 | <0.0001 | <0.0001 |
| Body mass index (BMI) (kg/m2) | 24(21–27) | 24(22–28) | 0.15 | |
| Waist-hip ratio (WHR) | 0.7(0.7–0.8) | 0.8(0.7–0.9) | 0.069 | |
| Menopause % | 52 | 42 | <0.0001 | <0.0001 |
| Diabetes % c | 1.4 | 1.4 | 1.00 | |
| Heredity for cardiovascular disease (CVD)d % | 9 | 10 | 0.56 | |
| History of arterial event % | 12 | 1 | <0.0001 | <0.0001 |
| History of venous event % | 14 | 1 | <0.0001 | <0.0001 |
| Total cholesterol mmol/l | 5.0(4.3–5.8) | 5.2(4.4–6.0) | 0.095 | |
| High-density lipoprotein (HDL) mmol/l | 1.3(1.1–1.7) | 1.5(1.2–1.8) | 0.012 | 0.62 |
| Low-density lipoprotein (LDL) mmol/l | 3.1(2.5–3.7) | 3.3(2.6–3.9) | 0.0052 | 0.26 |
| Triglycerides a (TG) mmol/l | 1.0(0.7–1.4) | 0.8(0.6–1.1) | <0.0001 | <0.0001 |
| Glucose mmol/l | 4.9(4.3–5.3) | 4.9(4.6–5.3) | 0.9959 | |
| Lupus-related risk factors | ||||
| High-sensitivity (hs) CRP amg/l | 1.5(0.7–4.4) | 1.0(0.5–2.2) | <0.0001 | <0.0001 |
| Fibrinogen g/l | 3.9(3.2–4.7) | 3.8(3.2–4.4) | 0.037 | 1.84 |
| Albumin g/l | 39(37–42) | 42(41–44) | <0.0001 | <0.0001 |
| Creatinine a μmol/l | 69(60–84) | 66(60–73) | <0.0001 | <0.0001 |
| Cystatin C a μmol/l | 1.0(0.9–1.3) | 0.8(0.7–0.9) | <0.0001 | <0.0001 |
| Albuminuria g % | 21 | 0.7 | <0.0001 | <0.0001 |
| Homocysteinea mol/l | 12.4(9.9–15.3) | 9.4(8.2–11.1) | <0.0001 | <0.0001 |
| Vascular cell adhesion molecule (VCAM)-1 * ng/l | 380(310–496) | 362(287–430) | 0.0007 | 0.035 |
| Interferon γ induced protein (IP)-10 a pg/l | 209(122–379) | 75(51–101) | <0.0001 | <0.0001 |
| Monocyte chemoattractant protein-1 (MCP-1) a pg/l | 184(112–280) | 72(29–112) | <0.0001 | <0.0001 |
| Complement factor (C) 3 g/l | 0.87(0.70–1.03) | 1.05(0.91–1.20) | <0.0001 | <0.0001 |
| C4 g/l | 0.14(0.10–0.19) | 0.21(0.17–0.25) | <0.0001 | <0.0001 |
| Lupus manifestations e % | ||||
| Malar rash | 52 | 0 | <0.0001 | <0.0001 |
| Photosensitivity | 69 | 19 | <0.0001 | <0.0001 |
| Discoid lesions | 20 | 0 | <0.0001 | <0.0001 |
| Oral ulcers | 33 | 3 | <0.0001 | <0.0001 |
| Arthritis | 86 | 4 | <0.0001 | <0.0001 |
| Serositis | 39 | 0.7 | <0.0001 | <0.0001 |
| Nephritis | 40 | 0.3 | <0.0001 | <0.0001 |
| CNS manifestations | 11 | 2 | <0.0001 | <0.0001 |
| Leucopenia | 50 | 1 | <0.0001 | <0.0001 |
| Lymphopenia | 52 | 0.9 | <0.0001 | <0.0001 |
| Thrombocytopenia | 21 | 0.9 | <0.0001 | <0.0001 |
| SLICC damage index>1 | 37 | - | - | |
| SLAM>6 | 49 | - | - | |
| Autoantibody positivity at inclusion % | ||||
| Anti-nuclear (ANA) IFL | 89 | - | - | |
| Anti-double stranded (ds) DNA | 36 | 1 | <0.0001 | <0.0001 |
| Anti-Smith (anti-Sm) | 19 | 0.4 | <0.0001 | <0.0001 |
| Anti-Sjogren Syndrome A (SSA) | 46 | 2 | <0.0001 | <0.0001 |
| Anti-SSB | 24 | 3 | <0.0001 | <0.0001 |
| Lupus anticoagulant (LA) | 16 | - | - | |
| Anti-cardiolipin (aCL) IgG | 16 | 0 | <0.0001 | <0.0001 |
| aCL IgM | 7 | 0.7 | 0.0001 | 0.0005 |
| anti-β2 glycoprotein-1 (aβ2GP1) IgG | 18 | 0 | <0.0001 | <0.0001 |
| aβ2GP1 IgM | 8 | 0.7 | 0.0001 | |
| Any antiphospholipid antibody (aPL) | 27 | - | - | |
| Triple aPL positivity[23] | 12 | - | - | |
| APS f % | 15 | 0 | - | |
| Current medication (if not stated otherwise) % | ||||
| Aspirin | 17 | 3 | <0.0001 | <0.0001 |
| Warfarin | 15 | 0.4 | <0.0001 | <0.0001 |
| Lipid-lowering drugs | 12 | 4 | 0.0002 | <0.0001 |
| Antihypertensive drugs | 37 | 13 | <0.0001 | <0.0001 |
| Current steroid dose a (mg/day) | 2.5(0–7.5) | 0 | <0.0001 | <0.0001 |
| Corticosteroids a (months) | 48(6–180) | 0 | <0.0001 | <0.0001 |
| Antimalaria | 34 | 0 | <0.0001 | <0.0001 |
| Mycophenolate mofetil | 7 | 0 | <0.0001 | <0.0001 |
| Azathioprine | 19 | 0 | <0.0001 | <0.0001 |
| Cyclophosphamide (ever) | 28 | 0 | <0.0001 | <0.0001 |
| Carotid ultrasound measurement | ||||
| Plaques % | 20 | 16 | 0.17 | 1.0 |
| mIMT (mm) a | 0.56(0.50–0.68) | 0.53(0.49–0.63) | <0.0001 | 0.0033 |
Distributions are given as median (interquartile range, IQR) unless indicated otherwise. P values ≤ 0.05 are presented.
a indicates not normally distributed variables.
b Defined as a systolic BP> 140 mm Hg and/or a diastolic BP> 90 mm Hg, or use of antihypertensive drugs, prescribed with the aim to reduce blood pressure.
c Defined according to SLICC[19], regardless use of hypoglycemic drugs
d Family history of CVD was defined as a first-degree relative who had presented with a myocardial infarction or stroke before the age of 55 years in males and 65 years in females[24].
e Defined according to Tan et al[16].
f APS = anti phospholipid syndrome defined according to Miyakis et al[22]
g defined as ≥1+ on urine dipstick.
h Bonferroni corrected p-values, assuming 50 independent variables, are given in the last column for all raw p-values, which were significant in the initial analysis.