Table 1.
Demographic and clinical characteristics of the RA and SLE study patients*
| Characteristic | RA patients (n = 124) | SLE patients (n = 103) | P |
|---|---|---|---|
| Demographics | |||
| Age, years | 52 (44–61) | 40 (30–46) | <0.001 |
| Sex, % female | 73 | 91 | <0.001 |
| White, % | 89 | 68 | <0.001 |
| Cardiovascular risk factors | |||
| Systolic blood pressure, mm Hg | 130 (116–142) | 117 (106–128) | <0.001 |
| Diastolic blood pressure, mm Hg | 74 (67–82) | 73 (65–81) | 0.28 |
| BMI, kg/m2 | 28 (24–32) | 27 (24–33) | 0.86 |
| Homocysteine, μmoles/liter | 10.2 (8.0–11.9) | 9.2 (7.3–11.1) | 0.02 |
| Cumulative smoking, pack-years | 0 (0–18) | 0 (0–4) | 0.11 |
| Cholesterol, mg/dl | 188 (160–213) | 165 (141–206) | 0.01 |
| Low-density lipoprotein, mg/dl | 114 (90–136) | 96 (81–130) | 0.008 |
| High-density lipoprotein, mg/dl | 44 (38–56) | 48 (36–55) | 0.84 |
| Lipoprotein(a), mg/dl | 6.9 (2.1–24.7) | 12.0 (5.0–37.5) | 0.001 |
| Triglycerides, mg/dl | 108 (76–141) | 99 (71–155) | 0.74 |
| Glucose, mg/dl | 86 (81–92) | 83 (75–90) | 0.003 |
| Insulin resistant, % | 49 | 41 | 0.21 |
| HOMA index | 2.0 (1.0–3.5) | 1.4 (0.8–2.6) | 0.007 |
| Measures of disease activity and damage | |||
| SLEDAI† | NA | 4 (1–6) | NA |
| SLICC/ACR‡ | NA | 0 (0–1) | NA |
| DAS28† | 2.9 (2.1–3.9) | NA | NA |
| M-HAQ§ | 0.4 (0.0–0.8) | 0.1 (0.0–0.6) | 0.03 |
| Current use of corticosteroids, no. (%) | 69 (56) | 61 (59) | 0.59 |
| Cumulative corticosteroid dose, gm | 2.8 (0.5–9.4) | 11.6 (2.7–26.5) | <0.001 |
| Other markers of inflammation | |||
| ESR, mm/hour | 13 (5–30) | 17 (9–37) | 0.06 |
| CRP, mg/liter | 3.6 (1.0–11.0) | 4.0 (0.6–7.0) | 0.10 |
| IL-6, pg/ml | 13.8 (4.0–44.9) | 5.5 (2.1–24.3) | <0.001 |
| TNFα, pg/ml | 4.9 (2.6–11.1) | 4.7 (3.0–7.6) | 0.24 |
Except where indicated otherwise, values are the median (interquartile range). P values were calculated using chi-square tests for categorical values and Wilcoxon’s rank sum tests for continuous variables. RA = rheumatoid arthritis; SLE = systemic lupus erythematosus; BMI = body mass index; HOMA = homeostasis model assessment; SLEDAI = Systemic Lupus Erythematosus Disease Activity Index; NA = not applicable; SLICC/ACR = Systemic Lupus International Collaborating Clinics/American College of Rheumatology; DAS28 = Disease Activity Score in 28 joints; M-HAQ = modified Health Assessment Questionnaire; ESR = erythrocyte sedimentation rate; CRP = C-reactive protein; IL-6 = interleukin-6; TNFα = tumor necrosis factor α.
Higher scores indicate greater disease activity.
Higher scores indicate greater disease-related damage.
Lower scores indicate better functional capacity.