Table 1

Baseline and early admission characteristics by trajectory groups in all cohort

VariablesAll subjects
(N=355 678)		AKI
(N=54 212, 15%)		Persistent AKI without renal recovery (N=14 122, 4%)Persistent AKI with renal recovery (N=8590, 2%)Rapidly reversed AKI (N=31 500, 9%)No AKI
(N=301 466, 85%)
Preadmission clinical characteristics
 Age, years, mean (SD)54 (19)60 (17)*61 (17)*†60 (17)*†59 (17)*53 (19)
 Female sex, n (%)196 023 (55)27 146 (50)*7137 (51)*‡4116 (48)*†15 893 (50)*168 877 (56)
  African American ethnicity, n (%)85 825 (24)12 411 (23)*3057 (22)*†1928 (22)*7426 (24)*73 414 (24)
  Distance from hospital (mile), median (IQR)14 (3–30)21 (3–37)*23 (9–41)*†‡24 (10–42)†18 (3–36)*14 (3–27)
Comorbidities, n (%)
 Hypertension225 192 (63)36 556 (67)*9100 (64)*†‡5929 (69)*21 527 (68)*188 636 (63)
 Chronic pulmonary disease149 551 (42)23 044 (43)*5517 (39)*†‡3771 (44)*13 756 (44)*126 507 (42)
 Cardiovascular disease129 930 (37)23 451 (43)*5619 (40)*†‡3960 (46)*†13 872 (44)*106 479 (35)
 Diabetes mellitus104 546 (29)18 331 (34)*4359 (31)*†‡2928 (34)*11 044 (35)*86 215 (29)
 Chronic kidney disease85 942 (24)21 421 (40)*5442 (39)*‡3864 (45)*†12 115 (38)*64 521 (21)
  Moderate/severe (≥G-stage 3)34 956 (41)11 739 (55)*3025 (56)*2211 (57)*†6503 (54)*26 236 (41)
  Preadmission estimated glomerular filtration rate (mL/min per 1.73 m2), median (IQR)63.6 (46.4–85.1)55.9 (37.9–78.7)*53.9 (32.6–81.1)*†54.1 (36.6–76.2)*†57.2 (40.1–78.6)*65.6 (49.5–86.6)
Admission characteristics, n (%)
 Emergent admission295 286 (83)45 927 (85)*12 091 (86)*†7355 (86)*†26 481 (84)*249 359 (83)
 Transfer from another hospital53 265 (15)13 706 (25)*4626 (33)*†2721 (32)*†6359 (20)*39 559 (13)
 Surgery on admission day51 310 (14)8327 (15)*2179 (15)*‡1455 (17)*†4693 (15)*42 983 (14)
 Surgery at any time72 541 (20)15 216 (28)*4068 (29)*†‡3272 (38)*†7876 (25)*57 325 (19)
Kidney function within 48 hours of the admission
AKI, n (%)37 973 (11)37 973 (70)*9706 (69)*†5908 (69)*†22 359 (71)*0 (0)
 Stage 125 963 (68)25 963 (68)*4538 (47)*†‡3132 (53)*†18 293 (82)*0 (0)
 Stage 26646 (18)6646 (18)*2328 (24)*†1473 (25)*†2845 (13)*0 (0)
 Stage 35364 (14)5364 (14)*2840 (29 *†‡1303 (22)*†1221 (5)*0 (0)
  Stage three without RRT4623 (12)4623 (12)*2217 (23)*†‡1195 (20)*†1211 (5)*0 (0)
  Stage three with RRT741 (2)741 (2)*623 (6)*†‡108 (2)*†10 (0)*0 (0)
Highest blood urea nitrogen (mg/dL), mean (SD)18 (13)30 (22)*35 (26)*†‡36 (25)*†27 (17)*15 (9)
Highest serum creatinine (mg/dL), median (IQR)0.9 (0.7–1.1)1.4 (1.0–1.9)*1.5 (0.9–2.4)*†‡1.6 (1.0–2.4)*†1.3 (1.0–1.7)*0.8 (0.7–1.0)
Reference creatinine (mg/dL), median (IQR)0.8 (0.7–1.0)0.8 (0.7–1.1)*0.8 (0.7–1.1)*†‡0.9 (0.7–1.2)*†0.8 (0.7–1.1)*0.8 (0.7–0.9)
Highest/reference creatinine, mean (SD)1.2 (0.6)1.8 (1.2*2.1 (1.8)*†1.9 (1.4)*†1.6 (0.7)*1.1 (0.2)
Count of nephrotoxic drug, mean (SD)
  Within 2 days after hospital admission0.86 (0.97)1.26 (1.03)*1.41 (1.03)*†1.39 (1.03)*†1.17 (1.02)*0.79 (0.94)
  Within 3 days after hospital admission0.92 (1.00)1.39 (1.07)*1.54 (1.07)*†1.55 (1.07)*†1.27 (1.06)*0.83 (0.97)
 Between hospital admission and first AKI onset1.33 (1.18)1.33 (1.18)1.49 (1.20)†1.47 (1.20)†1.23 (1.15)NA

  • *P<0.05 compared with no AKI.

  • †P<0.05 compared with rapidly reversed AKI.

  • ‡P<0.05 compared with persistent AKI with renal recovery.

  • §Cardiovascular disease was considered if there was a history of congestive heart failure, coronary artery disease of peripheral vascular disease.

  • AKI, acute kidney injury; NA, not applicable; RRT, renal replacement therapy.