Table 1

Baseline characteristics

VariableICPi-AKI (n=429)No ICPi-AKI (n=429)P value
Age at ICPi initiation, years, median (IQR)68 (59–75)65 (58–73)0.02
Male, n (%)266 (62.0)251 (58.5)0.32
Race, n (%)0.99
 White351 (81.8)350 (81.6)
 Black27 (6.3)24 (5.6)
 Asian21 (4.9)21 (4.9)
 Other/unknown30 (7.0)34 (7.9)
Comorbidities, n (%)
 Hypertension251 (58.5)229 (53.4)0.15
 Diabetes77 (17.9)61 (14.2)0.16
 CHF17 (4.0)9 (2.1)0.16
 COPD45 (10.5)46 (10.7)0.99
 Cirrhosis11 (2.6)10 (2.3)0.99
Body mass index, median (IQR)26 (23–30)26 (22–29)0.12
Baseline SCr, mg/dL, median (IQR)0.97 (0.80–1.21)0.88 (0.73–1.07)<0.001
Baseline eGFR,*(mL/min per 1.73 m2
 Median (IQR)73 (57–90)83 (66–97)<0.001
 eGFR categories, n (%)<0.001
  ≥90111 (25.9)168 (39.2)
  60–89192 (44.8)189 (44.1)
  45–5972 (16.8)44 (10.3)
  30–4443 (10.0)23 (5.4)
  <3011 (2.6)5 (1.2)
Autoimmune disease, n (%)42 (9.8)56 (13.1)0.16
Extrarenal irAE,† n (%)201 (46.9)123 (28.7)<0.001
Malignancy, n (%)0.01
 Melanoma104 (24.2)93 (21.7)
 Lung126 (29.4)133 (31.0)
 Genitourinary100 (23.8)70 (16.7)
 Other99 (23.6)133 (31.7)
PPI,‡ n (%)208 (45.5)115 (26.8)<0.001
Concomitant nephrotoxic chemotherapy,§ n (%)
 Cisplatin7 (1.6)NA
 VEGF/TKI23 (5.4)NA
 Other¶43 (10.0)NA
ICPi class, n (%)
 Anti-CTLA-4103 (24.0)95 (22.1)0.57
 Anti-PD-1347 (80.9)355 (82.8)0.54
 Anti-PD-L142 (9.8)30 (7.0)0.18
 Combo anti-CTLA-4+ anti-PD-1/PD-L199 (23.1)75 (17.5)0.05
  • Data are shown as median (IQR) and n (%).

  • Data on body mass index are missing in one patient with ICPi-AKI and one without ICPi-AKI. Data on PPI use are missing in two patients without ICPi-AKI. All other data are complete.

  • *Baseline eGFR calculated based on Chronic Kidney Disease-Epidemiology Collaboration equation.33

  • †Extrarenal irAEs were assessed prior to (>14 days) or concomitant (within 14 days before or after) with ICPi-AKI diagnosis among patients with ICPi-AKI, and at any time after ICPi initiation among patients without ICPi-AKI.

  • ‡PPIs were assessed in the 14 days preceding AKI among patients with ICPi-AKI, and were assessed at ICPi initiation in patients without ICPi-AKI.

  • §Concomitant chemotherapies were assessed in the 30 days preceding ICPi-AKI.

  • ¶Includes pemetrexed (n=28), carboplatin (n=23), BRAF inhibitors (n=2), and paclitaxel (n=1).

  • AKI, acute kidney injury; BRAF, v-raf murine sarcoma viral oncogene homolog B1; CHF, congestive heart failure; Combo, combination therapy; COPD, chronic obstructive pulmonary disease; CTLA-4, cytotoxic T lymphocyte-associated antigen 4; eGFR, estimated glomerular filtration rate; ICPi, immune checkpoint inhibitor; irAEs, immune-related adverse events; NA, not assessed; PD-1, programmed cell death 1; PD-L1, programmed death-ligand 1; PPI, proton pump inhibitor; SCr, serum creatinine; TKI, tyrosine kinase inhibitor; VEGF, vascular endothelial growth factor.