Table 1.
Study population characteristics
| Variable | AML (n = 645) | ALL (n = 121) | MDS (n = 35) | Total (n = 801) |
|---|---|---|---|---|
| Year of Treatment | ||||
| 2005 | 172 (27) | 49 (40) | 6 (17) | 227 (28) |
| 2006 | 168 (26) | 48 (40) | 8 (23) | 224 (28) |
| 2007 | 151 (23) | 24 (20) | 10 (29) | 185 (23) |
| 2008 | 109 (17) | 8 (23) | 117 (15) | |
| 2009 | 45 (7) | 3 (9) | 48 (6) | |
| Age | ||||
| Mean ± SD, yr | 58 ± 15 | 45 ± 19 | 64 ± 14 | 56 ± 16 |
| Age < 60 yr | 335 (52) | 90 (74) | 14 (40) | 439 (55) |
| Age ≥ 60 yr | 310 (48) | 31 (26) | 21 (60) | 362 (45) |
| Sex | ||||
| Male | 337 (52) | 66 (55) | 21 (60) | 424 (53) |
| Female | 308 (48) | 55 (45) | 14 (40) | 377 (47) |
| Ethnicity | ||||
| White | 474 (73) | 70 (58) | 29 (83) | 573 (72) |
| Hispanic | 74 (11) | 36 (30) | 4 (11) | 114 (14) |
| Black | 57 (9) | 7 (6) | 1 (3) | 65 (8) |
| Asian | 27 (4) | 5 (4) | 0 (0) | 32 (4) |
| Other | 13 (2) | 3 (2) | 1 (3) | 17 (2) |
| Baseline laboratory values, mean ± SD | ||||
| Hemoglobin, g/dl | 8.6 ± 1.6 | 9.1 ± 3.2 | 9.2 ± 1.5 | 8.7 ± 1.9 |
| Platelets, ×103/μL | 68 ± 69 | 85 ± 97 | 70 ± 70 | 70 ± 74 |
| β2-microglobulin, mg/L* | 3.2 ± 2.1 | 3.1 ± 1.5 | 3.1 ± 1.2 | 3.2 ± 2.0 |
| Albumin low, g/dl | 3.5 ± 0.7 | 3.5 ± 0.6 | 3.8 ± 0.6 | 3.5 ± 0.7 |
| Bilirubin elevated, mg/dl | 0.7 ± 0.8 | 0.7 ± 0.6 | 0.5 ± 0.3 | 0.7 ± 0.8 |
| Creatinine elevated, mg/dl | 1.0 ± 0.4 | 1.0 ± 0.4 | 1.0 ± 0.3 | 1.0 ± 0.4 |
| ECOG performance status | ||||
| 0–1 | 529 (82) | 96 (79) | 34 (97) | 659 (82) |
| 2–4 | 116 (18) | 25 (21) | 1 (3) | 142 (18) |
| Laminar flow room | ||||
| Yes | 414 (64) | 31 (26) | 18 (52) | 463 (58) |
| No | 231 (36) | 90 (74) | 17 (49) | 338 (42) |
| Intensive chemotherapy | ||||
| Yes | 393 (61) | 0 (0) | 7 (20) | 521 (65) |
| No | 252 (39) | 121 (100) | 28 (80) | 280 (35) |
| Length of stay, d† | ||||
| Mean | 23.4 | 13.4 | 21.7 | 21.9 |
| Median (IQR) | 24 (13–30) | 9 (6–17) | 24 (8–31) | 23 (10–29) |
| ICU days, mean† | ||||
| Mean | 1.0 | 0.5 | 0.6 | 0.9 |
| Median (IQR) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) |
| Charges, mean† | ||||
| Mean | $185,604 | $123,200 | $149,273 | $174,753 |
| Median (IQR) | $154,043 (97,408–220,497) | $90,244 (64,363–149,276) | $109,521 (64,527–190,183) | $143,694 (87,070–206,768) |
| Pneumonia syndrome‡ | ||||
| Present at start of induction | 76 (12) | 8 (7) | 1 (3) | 85 (11) |
| Occurring after induction | 125 (19) | 11 (9) | 12 (34) | 148 (18) |
| None | 444 (69) | 102 (84) | 22 (63) | 569 (71) |
| Response to treatment§ | ||||
| Complete response | 406 (63) | 108 (89) | 14 (40) | 528 (66) |
| CRP | 27 (4) | 1 (1) | 4 (11) | 32 (4) |
| Partial response | 13 (2) | 1 (1) | 1 (3) | 15 (2) |
| Resistant | 149 (23) | 3 (3) | 11 (31) | 163 (20) |
| Failed | 50 (8) | 8 (7) | 5 (14) | 63 (8) |
| Survival status at 33 d | ||||
| Dead | 41 (6) | 8 (7) | 1 (3) | 50 (6) |
| Alive | 604 (94) | 113 (93) | 34 (97) | 751 (94) |
Definition of abbreviations: ANC = absolute neutrophil count; CRP = complete response with insufficient platelet recovery; IQR = interquartile range.
Data are presented as n (%) unless otherwise noted.
Data on β2-microglobulin were only available for 474 patients and therefore were not included in the multivariate model. For all other covariates, n = 801.
This variable is not normally distributed. Mean value is given for budget purposes only and is not as valid as medians as a measure of central tendency.
Pneumonia occurring either within 2 weeks before induction or during the 33 days subsequent to the first day of induction chemotherapy.
Complete response defined as < 5% blasts with ANC >1,000 and platelet count > 100,000; CRP defined as the first two of these three criteria with < 100,000 platelets. Resistant defined as failure to achieve remission with induction regimen, treatment subsequently changed. Failed defined as failure to achieve remission, with death occurring before any documented response to induction regimen.