Table 1.
Baseline patient characteristics
| WBC <3,000 (N = 31) | 3,000≤ WBC <4,000 (N = 167) | 4,000≤ WBC <5,000 (N = 241) | WBC ≥5,000 (N = 284) | |
|---|---|---|---|---|
| Sex, female, N (%) | 9 (29.0) | 74 (44.3) | 93 (38.6) | 113 (39.8) |
| Age, median [IQR], years | 41 [31–55] | 49 [36–63] | 46 [31–58] | 45 [34–55] |
| Disease extension, N (%) | ||||
| Extensive | 24 (77.4) | 126 (75.5) | 180 (74.7) | 213 (75.0) |
| Left sided | 7 (22.6) | 39 (23.3) | 59 (24.5) | 63 (22.2) |
| Others | 0 (0) | 2 (1.2) | 2 (0.8) | 8 (2.8) |
| Smoking status, N (%) | ||||
| Current smoker | 0 (0) | 7 (4.2) | 21 (8.7) | 33 (11.6) |
| Non-current smoker | 20 (64.5) | 122 (73.1) | 169 (70.1) | 178 (62.7) |
| Missing data | 11 (35.5) | 38 (22.8) | 51 (21.2) | 73 (25.7) |
| Dose of thiopurinea, N (%) | ||||
| Low | 17 (54.8) | 108 (64.7) | 143 (59.3) | 175 (61.6) |
| Medium | 10 (32.3) | 29 (17.4) | 51 (21.2) | 69 (24.3) |
| High | 4 (12.9) | 30 (18.0) | 47 (19.5) | 40 (14.1) |
| Duration of thiopurine use, N (%) | ||||
| ≥2 years | 18 (58.1) | 116 (69.5) | 185 (76.8) | 204 (71.8) |
| 1–2 years | 5 (16.1) | 31 (18.6) | 31 (12.9) | 43 (15.1) |
| <1 year | 7 (22.6) | 17 (10.2) | 23 (9.6) | 37 (13.0) |
| Missing data | 1 (3.2) | 3 (1.8) | 2 (0.8) | 0 (0) |
| Concomitant use of 5-ASA, N (%) | 27 (87.1) | 149 (89.2) | 214 (88.8) | 256 (90.1) |
| Neutrophil counts, median [IQR], µL | 1,444 [1,170–1,725] | 2,139 [1,890–2,343] | 2,753 [2,381–3,030] | 4,049 [3,339–4,751] |
| Lymphocyte counts, median [IQR], µL | 805 [686–1,025] | 930 [792–1,164] | 1,190 [968–1,402] | 1,450 [1,091–1,820] |
| MCV, median [IQR], fL | 99 [95–105] | 96 [93–100] | 95 [91–99] | 92 [88–96] |
| CRP, median [IQR], mg/L | 0.5 [0.2–1.0] | 0.3 [0.1–0.7] | 0.4 [0.2–1.0] | 0.6 [0.2–1.3] |
The values are described as N (%) or median [IQR].
aThiopurine doses are categorized into three groups: low, AZA ≤50 mg or 6-MP ≤30 mg; medium, 50< AZA <100 mg or 30< 6-MP <60 mg; and high, AZA ≥100 mg or 6-MP ≥60 mg.
5-ASA, 5-aminosalicylic acid; 6-MP, 6-mercaptopurine; AZA, azathioprine; CRP, C-reactive protein; IQRs, interquartile ranges; MCV, mean corpuscular volume; WBC, white blood cell.