Clinical and laboratory characteristics of cases and controls
| Parameter . | Cases (n = 57) . | Controls (n = 105) . | P . |
|---|---|---|---|
| Age, y | 58 | 60 | .69 |
| Gender, male % | 61 | 62 | .95 |
| Ethnicity, white % | 95 | 95 | 1.00 |
| β2-microglobulin, mcg/mL (n) | 2.04 (34) | 2.20 (55) | .90 |
| C-reactive protein, mg/dL (n) | 0.40 (23) | 0.42 (24) | .78 |
| Hemoglobin, g/dL (n) | 12.1 (53) | 12.0 (99) | .60 |
| Creatinine, mg/dL (n) | 1.1 (54) | 1.0 (100) | .97 |
| Mean urine M protein, g/dL (n) | 0.56 (45) | 0.28 (59) | .26 |
| Mean serum M protein, g/dL (n) | 1.24 (44) | 1.71 (83) | .03 |
| Parameter . | Cases (n = 57) . | Controls (n = 105) . | P . |
|---|---|---|---|
| Age, y | 58 | 60 | .69 |
| Gender, male % | 61 | 62 | .95 |
| Ethnicity, white % | 95 | 95 | 1.00 |
| β2-microglobulin, mcg/mL (n) | 2.04 (34) | 2.20 (55) | .90 |
| C-reactive protein, mg/dL (n) | 0.40 (23) | 0.42 (24) | .78 |
| Hemoglobin, g/dL (n) | 12.1 (53) | 12.0 (99) | .60 |
| Creatinine, mg/dL (n) | 1.1 (54) | 1.0 (100) | .97 |
| Mean urine M protein, g/dL (n) | 0.56 (45) | 0.28 (59) | .26 |
| Mean serum M protein, g/dL (n) | 1.24 (44) | 1.71 (83) | .03 |
Laboratory studies were drawn within 30 days of the bone marrow plasma cell labeling index. Cases had a PCLI of at least 1.0%, and controls had a PCLI of less than 1.0%.