Factors associated with probable sarcopenia in patients with SLE (n=82)
| Lupus (n=82) | No sarcopenia (n=40) | Probable sarcopenia (n=42) | P value |
| Age, years | 38.5±9.2 | 40.7±11.9 | 0.18 |
| Height, cm | 163.6±4.9 | 160.3±6.6 | 0.01 |
| Weight, kg | 67.9±13.2 | 64.8±12.5 | 0.28 |
| BMI, kg/m2 | 25.3±4.9 | 25.2±4.3 | 0.87 |
| Hand grip, kg | 25.8±2.8 | 17.7±2.7 | <0.001 |
| SMMI*, kg | 25.3±3.0 | 22.7±3.3 | 0.03 |
| SMMI (BMI)*, kg/(kg/m²) | 0.98±0.16 | 0.98±0.20 | 0.92 |
| PGA | 1 (0–1) | 1 (0–1) | 0.09 |
| SLEDAI-2K score | 9 (4.2–18) | 8 (6–14) | 0.58 |
| ANA positivity, n (%) | |||
| Yes | 38 (95) | 39 (92.9) | 0.68 |
| No | 2 (5) | 3 (7.1) | |
| Anti-dsDNA, IU/µL | 415 (140–731) | 212 (100–358) | 0.01 |
| C3, mg/dL | 70.5 (56.2–85.1) | 77.5 (59.1–93.5) | 0.32 |
| C4, mg/dL | 11.1 (8.5–15.4) | 12.2 (8.2–15.6) | 0.63 |
| Symptom duration, months | 120 (60–156) | 114 (60–159) | 0.80 |
| Disease duration, months | 102 (39–144) | 90 (36–144) | 0.58 |
| Being married, n (%) | |||
| Yes | 26 (65) | 31 (73.8) | 0.38 |
| No | 14 (35) | 11 (26.2) | |
| In employment, n (%) | |||
| Yes | 9 (22.5) | 9 (21.4) | 0.90 |
| No | 31 (77.5) | 33 (78.6) | |
| Smoking, n (%) | |||
| Yes | 8 (20) | 8 (19) | 0.91 |
| No | 32 (80) | 34 (81) | |
| Delay in diagnosis, n (%) | |||
| Yes | 16 (40) | 17 (40.5) | 0.96 |
| No | 24 (60) | 25 (59.5) | |
| Neurological disorder, n (%) | |||
| Yes | 5 (12.5) | 5 (11.9) | 0.93 |
| No | 35 (87.5) | 37 (88.1) | |
| Articular involvement, n (%) | |||
| Yes | 23 (57.5) | 28 (66.7) | 0.73 |
| No | 17 (42.5) | 14 (33.3) | |
| Mucocutaneous involvement, n (%) | |||
| Yes | 30 (75) | 32 (76.2) | 0.90 |
| No | 10 (25) | 10 (23.8) | |
| Serosal involvement, n (%) | |||
| Yes | 4 (10) | 9 (11.9) | 0.78 |
| No | 36 (90) | 73 (88.1) | |
| Renal involvement, n (%) | |||
| Yes | 12 (30) | 9 (21.4) | 0.37 |
| No | 28 (70) | 33 (78.6) | |
| Haematological involvement, n (%) | |||
| Yes | 10 (25) | 7 (16.7) | 0.35 |
| No | 30 (75) | 35 (83.3) | |
| Immunological involvement, n (%) | |||
| Yes | 39 (97.5) | 39 (92.9) | 0.61 |
| No | 1 (2.5) | 3 (7.1) | |
| Fatigue, n (%) | |||
| Yes | 18 (45) | 24 (57.1) | 0.27 |
| No | 22 (55) | 18 (42.9) | |
| Weight loss, n (%) | |||
| Yes | 4 (10) | 7 (16.7) | 0.37 |
| No | 36 (90) | 35 (83.3) | |
| Anti-Ro (SS-A) positivity, n (%) | |||
| Yes | 14 (35) | 16 (38.1) | 0.77 |
| No | 26 (65) | 26 (61.9) | |
| Anti-La (SS-B) positivity, n (%) | |||
| Yes | 6 (15) | 4 (9.5) | 0.51 |
| No | 34 (85) | 38 (90.5) | |
| Anti-Ro52 positivity, n (%) | |||
| Yes | 9 (22.5) | 10 (23.8 | 0.88 |
| No | 31 (77.5) | 32 (76.2) | |
| Anti-Sm positivity, n (%) | |||
| Yes | 8 (20) | 5 (11.9) | 0.31 |
| No | 32 (80) | 37 (88.1) | |
| Anti-RNP positivity, n (%) | 0.01 | ||
| Yes | 16 (40) | 7 (16.7) | |
| No | 24 (60) | 35 (83.3) | |
| Anti-dsDNA positivity, n (%) | |||
| Yes | 36 (90) | 32 (76.2) | 0.09 |
| No | 4 (10) | 10 (23.8) | |
| Low-dose corticosteroid use, n (%) | |||
| Yes | 11 (27.5) | 15 (35.7) | 0.42 |
| No | 29 (72.5) | 27 (64.3) |
Values are given as n (%), unless otherwise stated.
Median (25th–75th percentile).
*Bioimpedance analysis was conducted on 31 patients with SLE, representing 37.8% of the study population.
anti-dsDNA, anti-double-stranded DNA; BMI, body mass index; PGA, Physician Global Assessment; RNP, ribonucleoprotein; SLEDAI-2K, SLE Disease Activity Index 2000; SMMI, skeletal muscle mass index.