Table 3.
Impact of dose on MTX pharmacokinetics and AKI
| Variables | MTX dose: ≤3.5 g/m2 N = 43 |
MTX dose: 8 g/m2 N = 37 |
P value |
|---|---|---|---|
| Age (years) | 68.4 (59.2–76.6) | 68.8 (61.4–73.7) | 0.835 |
| Sex (male) | 33 (76) | 21 (56) | 0.0962 |
| Protocol dose (g/m2) | 2.6 (1.75–3.48) | 6.0 (4.7–7.7) | <0.0001 |
| Total dose (g) | 5.1 (3.4–6.9) | 11.5 (9.1–13.75) | <0.0001 |
| Kidney parameters at baseline | |||
| Serum creatinine (mg/dL) | 0.90 (0.79–1.08) | 0.89 (0.66–1.09) | 0.365 |
| Cystatin C (mg/dL) | 1.03 (0.86–1.17) | 1.08 (0.90–1.23) | 0.352 |
| Estimated kidney function (mL/min) | |||
| CKD-EPI eGFRcreatinine | 89.3 (71.4–96.3) | 90.1 (68.2–102.8) | 0.647 |
| CKD-EPI eGFRcystatin C | 74.0 (60.7–89.7) | 65.4 (56.0–85.1) | 0.249 |
| CKD-EPI eGFRcreatinine-cystatin C | 82.5 (69.3–96.5) | 80.2 (63.8–95.4) | 0.661 |
| Albumin at baseline (mg/L) | 3.9 (3.3–4.2) | 3.8 (3.5–4.1) | 0.850 |
| Clearance of methotrexate (L/h) | 11.9 (10.6–13.1) | 11.4 (10.6–12.1) | 0.307 |
| Occurrence of any stage of AKI (N = 17) | 13 (30)a | 4 (11)a | 0.054 |
aPercent of column total
AKI acute kidney injury, CKD-EPI Chronic Kidney Disease Epidemiology Collaboration, eGFR estimated glomerular filtration rate, MTX methotrexate