Demographic data and laboratory features at diagnosis and comparison of the MGUS and MGUS-RD cohorts
| Parameter . | MGUS (n = 2680) . | MGUS-RD (n = 255) . | ||
|---|---|---|---|---|
| Median age (range), y | 68 (18-97) | 65 (25-92) | ||
| Sex* | ||||
| Female | 1117 | 42 | 46 | 57 |
| Male | 1563 | 58 | 109 | 43 |
| Ig heavy chain* | ||||
| IgG | 1808 | 68 | 158 | 62 |
| IgM | 491 | 18 | 48 | 19 |
| IgA | 209 | 8 | 28 | 11 |
| IgD | 0 | 0 | 1 | 0.4 |
| Biclonal gammopathy | ||||
| IgG + IgM | 92 | 3 | 9 | 4 |
| IgG + IgA | 35 | 1 | 4 | 1 |
| IgA + IgM | 5 | 0.2 | 0 | 0 |
| IgA + IgG + IgM | 2 | 0.1 | 0 | 0 |
| Light chain only | 38 | 1 | 7 | 3 |
| Ig light chain | ||||
| Kappa | 1531 | 57 | 136 | 53 |
| Lambda | 983 | 37 | 103 | 40 |
| Both | 153 | 6 | 13 | 5 |
| Not measurable | 13 | 0.5 | 3 | 1 |
| Lactate dehydrogenase >ULN | 679 | 27 | 56 | 24 |
| Hemoglobin ≤12 g/dL | 968 | 37 | 101 | 40 |
| Median M-protein (range), g/dL | 0.34 (0.01-2.89) | 0.35 (0.07-2.54) | ||
| Plasma cells in bone marrow | 619 | 44 | ||
| Median percentage (IQR) | 1.5 (0.5-3.0) | 2.0 (1.0-3.0) | ||
| C-reactive protein >ULN | 1484 | 57 | 159 | 63 |
| Positive rheumatoid factor* | 67 | 14 | 67 | 32 |
| Positive ACPA* | 5 | 2 | 38 | 25 |
| Positive ANCA* | 4 | 1 | 7 | 6 |
| Positive ANA* | 104 | 12 | 61 | 28 |
| MGUS with RD | ||||
| RA | 68 | 27 | ||
| SpA | 22 | 9 | ||
| Connective tissue diseases or ANCA-associated vasculitis | 86 | 34 | ||
| PMR/large vessel-giant cell arteritis | 47 | 18 | ||
| Gouty arthritis | 32 | 13 | ||
| Treatment received | ||||
| Yes | 225 | 88 | ||
| No | 30 | 12 | ||
| DMARDs | 15 | 6 | ||
| Biologic agents | 2 | 1 | ||
| GC | 64 | 25 | ||
| Biological agent + glucocorticoids | 4 | 2 | ||
| DMARDs + biologic agents | 2 | 1 | ||
| DMARDs + glucocorticoids | 74 | 29 | ||
| DMARDs + biologic agents + glucocorticoids | 29 | 11 | ||
| Others | 35 | 14 | ||
| Parameter . | MGUS (n = 2680) . | MGUS-RD (n = 255) . | ||
|---|---|---|---|---|
| Median age (range), y | 68 (18-97) | 65 (25-92) | ||
| Sex* | ||||
| Female | 1117 | 42 | 46 | 57 |
| Male | 1563 | 58 | 109 | 43 |
| Ig heavy chain* | ||||
| IgG | 1808 | 68 | 158 | 62 |
| IgM | 491 | 18 | 48 | 19 |
| IgA | 209 | 8 | 28 | 11 |
| IgD | 0 | 0 | 1 | 0.4 |
| Biclonal gammopathy | ||||
| IgG + IgM | 92 | 3 | 9 | 4 |
| IgG + IgA | 35 | 1 | 4 | 1 |
| IgA + IgM | 5 | 0.2 | 0 | 0 |
| IgA + IgG + IgM | 2 | 0.1 | 0 | 0 |
| Light chain only | 38 | 1 | 7 | 3 |
| Ig light chain | ||||
| Kappa | 1531 | 57 | 136 | 53 |
| Lambda | 983 | 37 | 103 | 40 |
| Both | 153 | 6 | 13 | 5 |
| Not measurable | 13 | 0.5 | 3 | 1 |
| Lactate dehydrogenase >ULN | 679 | 27 | 56 | 24 |
| Hemoglobin ≤12 g/dL | 968 | 37 | 101 | 40 |
| Median M-protein (range), g/dL | 0.34 (0.01-2.89) | 0.35 (0.07-2.54) | ||
| Plasma cells in bone marrow | 619 | 44 | ||
| Median percentage (IQR) | 1.5 (0.5-3.0) | 2.0 (1.0-3.0) | ||
| C-reactive protein >ULN | 1484 | 57 | 159 | 63 |
| Positive rheumatoid factor* | 67 | 14 | 67 | 32 |
| Positive ACPA* | 5 | 2 | 38 | 25 |
| Positive ANCA* | 4 | 1 | 7 | 6 |
| Positive ANA* | 104 | 12 | 61 | 28 |
| MGUS with RD | ||||
| RA | 68 | 27 | ||
| SpA | 22 | 9 | ||
| Connective tissue diseases or ANCA-associated vasculitis | 86 | 34 | ||
| PMR/large vessel-giant cell arteritis | 47 | 18 | ||
| Gouty arthritis | 32 | 13 | ||
| Treatment received | ||||
| Yes | 225 | 88 | ||
| No | 30 | 12 | ||
| DMARDs | 15 | 6 | ||
| Biologic agents | 2 | 1 | ||
| GC | 64 | 25 | ||
| Biological agent + glucocorticoids | 4 | 2 | ||
| DMARDs + biologic agents | 2 | 1 | ||
| DMARDs + glucocorticoids | 74 | 29 | ||
| DMARDs + biologic agents + glucocorticoids | 29 | 11 | ||
| Others | 35 | 14 | ||
All data are n (%), unless otherwise indicated.
ACPA, anti-citrullinated protein/peptide antibody; ANA, antinuclear antibody; ANCA, antineutrophil cytoplasmic antibody; DMARDs, disease-modifying antirheumatic drugs; GC, glucocorticoids; ULN, upper limit of normal.
Indicates significant results of exact χ2 or Mann-Whitney U tests. A P value < .05 was considered statistically significant. No correction for multiple testing was applied.