Table 1.
Characteristics and laboratory parameters in patients <50 vs ≥50 years
| Characteristics/parameters | Age categories
|
P-values | |
|---|---|---|---|
| <50 years | ≥50 years | ||
| N (%) | 194 (21) | 746 (79) | – |
| Male/female (%) | 113/81 (58.3) | 457/289 (61.2) | 0.459 |
| IgA (%) | 28/194 (14.4) | 141/746 (18.9) | 0.149 |
| IgG (%) | 75/194 (38.7) | 341/746 (45.7) | 0.078 |
| IgD (%) | 20/194 (10.3) | 41/746 (5.5) | 0.015 |
| Nonsecretory (%) | 6/194 (3.1) | 21/746 (2.8) | 0.837 |
| Light-chain only (%) | 64/194 (33.0) | 195/746 (26.1) | 0.057 |
| DS stage 2/3 (%) | 33/159 (17.2) | 99/639 (13.4) | 0.201 |
| ISS stage 1–2/3 (%) | 114/74 (60.6) | 355/365 (49.3) | 0.007 |
| EMD (%) | 16/162 (9.2) | 47/644 (6.8) | 0.316 |
| >3 lytic lesions | 82/109 | 334/403 | 0.569 |
| Creatinine ≥2 mg/dL | 41/151 (21.4) | 185/553 (25.1) | 0.300 |
| β2 (mg/dL) | 5.96±6.94 | 7.12±8.22 | 0.090 |
| β2 ≥3.5 mg/dL (%) | 45.8 | 62 | <0.001 |
| ALB (g/L) | 37.3±7.5 | 33.5±7.5 | <0.001 |
| ALB <35 g/L (%) | 37.1 | 57.9 | <0.001 |
| LDH (U/L) | 213.06±192.17 | 193.29±134 | 0.201 |
| Uric acid (U/L) | 377.57±174.42 | 398.64±172.83 | 0.210 |
| Creatinine (μmol/L) | 149.29±201.67 | 141.91±145.60 | 0.648 |
| CRP (mg/L) | 10.69±25.83 | 9.96±21.80 | 0.718 |
| CRP ≥10 mg/L (%) | 19.0 | 19.4 | 0.891 |
| Bone marrow plasma cell (%) | 31.62±27.39 | 31.79±25.61 | 0.936 |
| WBC | 5.49±2.74 | 5.65±2.32 | 0.550 |
| Hb | 97.73±27.26 | 93.56±26.12 | 0.094 |
| Plt | 172.75±94.2 | 168.47±81.57 | 0.574 |
Abbreviations: DS, Durie–Salmon; ISS, International Staging System; EMD, extramedullary plasmacytoma/disease; ALB, albumin; LDH, lactate dehydrogenase; CRP, C-reactive protein; WBC, white blood cell; Hb, hemoglobin; Plt, platelet.