Table 1.
Demographic characteristics of the study subjects
| Characteristic | All (n = 335) | Male |
Female |
||||||
|---|---|---|---|---|---|---|---|---|---|
| All (n = 51) | BMI < 25 kg/m2 (n = 33) | BMI ≥ 25 kg/m2 (n = 18) | p value | All (n = 284) | BMI < 25 kg/m2 (n = 193) | BMI ≥ 25 kg/m2 (n = 91) | p value | ||
| Age, yr | 56.0 ± 11.9 | 60.8 ± 1.79 | 65.6 ± 9.73 | 52 ± 13.27 | < 0.001 | 55.17 ± 0.69 | 53.55 ± 11.5 | 58.61 ± 11.25 | < 0.001 |
| HTN | 88 (26.3) | 14 (27.5) | 9 (27.3) | 5 (27.8) | 0.759 | 74 (26.1) | 44 (22.8) | 30 (33) | 0.040 |
| DM | 33 (9.9) | 11 (21.6) | 6 (18.2) | 5 (27.8) | 0.290 | 22 (7.7) | 10 (5.2) | 12 (13.2) | 0.014 |
| RA duration, yr | 6 (3.5–9) | 6 (3–8) | 5 (3–8.5) | 6 (3.75–7.25) | 0.797 | 6 (4–9) | 6 (4–9) | 7 (4–9) | 0.569 |
| Seropositivitya | 276 (87.4) | 42 (82.4) | 27 (81.8) | 15 (83.3) | 0.892 | 234 (82.4) | 167 (86.5) | 67 (73.6) | 0.008 |
| CRPb, mg/L | 1.04 (0–2.94) | 2.34 (0–6.28) | 1.58 (0–9.42) | 2.58 (0–3.85) | 0.936 | 0.88 (0.–2.72) | 0 (0–1.93) | 1.39 (0–3.2) | 0.008 |
| ESR, mm/hr | 21 (12–31) | 12(8–25) | 12 (7–26.5) | 12.5 (8–25) | 0.782 | 22 (13–32.7) | 18 (12–31) | 27 (18–33) | 0.007 |
| DAS28-ESR | 3.55 ± 1.14 | 2.91 ± 0.14 | 2.96 ± 1.05 | 2.83 ± 1.08 | 0.324 | 3.67 ± 0.06 | 3.54 ± 1.1 | 3.93 ± 1.11 | 0.011 |
| DAS28-P | 0.36 ± 0.17 | 0.31 ± 0.02 | 0.31 ± 0.17 | 0.32 ± 0.19 | 0.782 | 0.36 ± 0.01 | 0.36 ± 0.16 | 0.38 ± 0.17 | 0.259 |
| HAQ | 0.25 (0–0.63) | 0 (0–0.38) | 0 (0.–0.19) | 0.19 (0.0.41) | 0.133 | 0.25 (0.–0.63) | 0.25 (0–0.63) | 0.25 (0–1) | 0.175 |
| VAS pain, range (0–100) | 40 (20–50) | 30 (20–50) | 40 (15–50) | 30 (20–50) | 0.858 | 40 (20–50) | 35 (20–50) | 50 (20–60) | 0.012 |
| GC use | 252 (75.2) | 43 (84.3) | 29 (87.9) | 14 (77.8) | 0.343 | 209 (73.6) | 145 (75.1) | 64 (70.3) | 0.392 |
| BMI, kg/m2 | 23.6 ± 3.6 | 23.89 ± 0.52 | 21.8 ± 2.43 | 27.72 ± 2.43 | < 0.001 | 23.59 ± 0.22 | 21.59 ± 2.25 | 27.8 ± 2.37 | < 0.001 |
| Body fat mass, kg | 19.3 (15.6–24.1) | 16.7 (14–22) | 15.6 (11.4–18.65) | 22.65 (19.12–28.37) | < 0.001 | 19.55 (16.12–24.4) | 17.4 (14.05–19.8) | 27.2 (24.1–31) | < 0.001 |
| Skeletal muscle mass, kg | 20.9 (18.9–23.2) | 27.6 (24.8–30.9) | 25.6 (22.95–28.4) | 31.8 (28.1–36.97) | < 0.001 | 20.3 (18.62–22.1) | 19.7 (17.9–21.3) | 21.6 (19.7–23.7) | < 0.001 |
| Body fat/skeletal mass ratio | 0.91 (0.7–1.1) | 0.99 (0.77–1.3) | 1.01 (0.75–1.29) | 0.95 (0.82–1.32) | 0.921 | 0.9 (0.73–1.13) | 0.89 (0.69–1.12) | 0.94 (0.79–1.18) | 0.081 |
Values are presented as mean ± SD, number (%), or median (interquartile range).
BMI, body mass index; HTN, hypertension; DM, diabetes mellitus; RA, Rheumatoid arthritis; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; DAS28, disease activity score in 28 joints; DAS28-P, an index derived to measure the subjective component of DAS28; HAQ, health assessment questionnaire; VAS, visual analogue scale; GC, glucocorticoid; BMI, body mass index.
a
Seropositivity was defined as either rheumatoid factor or anti-citrullinated protein antibody positivity.
b
The reporting limit was < 0.1 mg/L, which was given a value of 0 for analysis.