Table. Patient Characteristics.
| Characteristic | Patients, No. (%) | |||
|---|---|---|---|---|
| Overall | eGFRcys >30% lower than eGFRcr | Concordant eGFR | eGFRcys >30% higher than eGFRcr | |
| No. of patients | 1869 | 543 | 1131 | 195 |
| Age, mean (SD), y | 66 (14) | 68 (14) | 67 (14) | 60 (13) |
| Sex | ||||
| Female | 921 (49) | 277 (51) | 544 (48) | 100 (51) |
| Male | 948 (51) | 266 (49) | 587 (52) | 95 (49) |
| Race and ethnicitya | ||||
| African American or Black | 159 (9) | 38 (7) | 89 (8) | 32 (16) |
| Asian | 67 (4) | 19 (4) | 38 (3) | 10 (5) |
| Hispanic or Latino | 78 (4) | 22 (4) | 49 (4) | 7 (4) |
| White | 1486 (80) | 444 (82) | 904 (80) | 138 (71) |
| Otherb | 79 (4) | 20 (4) | 51 (5) | 8 (4) |
| BMIc | ||||
| Underweight: <18.5 | 53 (3) | 25 (5) | 25 (2) | 3 (2) |
| Healthy weight: 18.5-24.9 | 427 (23) | 120 (22) | 256 (23) | 51 (26) |
| Overweight: 25-29.9 | 927 (50) | 262 (48) | 562 (50) | 103 (53) |
| Obese: ≥30 | 462 (25) | 136 (25) | 288 (26) | 38 (20) |
| Smoking | 769 (41) | 254 (47) | 459 (41) | 56 (29) |
| Comorbidities | ||||
| Hypertension | 1506 (81) | 476 (88) | 902 (80) | 128 (66) |
| CAD | 927 (50) | 352 (65) | 508 (45) | 67 (34) |
| Diabetes | 936 (50) | 366 (67) | 514 (45) | 56 (28) |
| Cirrhosis | 100 (5) | 57 (11) | 40 (4) | 3 (2) |
| HIV infection | 78 (4) | 19 (4) | 45 (4) | 14 (7) |
| Malnutrition | 256 (14) | 90 (17) | 146 (13) | 20 (10) |
| Thyroid disease | 485 (26) | 169 (31) | 266 (24) | 50 (26) |
| CKDd | ||||
| eGFR: <30 mL/min/1.73m2 | 483 (47) | 196 (51) | 249 (44) | 38 (54) |
| eGFR: 30-50 mL/min/1.73m2 | 540 (53) | 190 (49) | 318 (56) | 32 (46) |
| Medication use | ||||
| ACEI or ARB | 1053 (56) | 320 (59) | 650 (58) | 83 (43) |
| Proton pump inhibitors | 1219 (65) | 411 (76) | 711 (63) | 97 (50) |
| Diuretics | 1209 (65) | 444 (82) | 679 (60) | 86 (44) |
| Corticosteroids | 377 (20) | 197 (36) | 161 (14) | 19 (10) |
| Laboratory study, median (IQR) | ||||
| Serum creatinine, mg/dL | 1.36 (1.02-1.84) | 1.29 (0.92-1.78) | 1.38 (1.05-1.84) | 1.43 (1.17-2.16) |
| Serum cystatin C, mg/L | 1.54 (1.12-2.20) | 2.08 (1.60-2.90) | 1.39 (1.08-1.92) | 0.98 (0.84-1.52) |
| eGFRcr-cys, mL/min/1.73m2 | 46 (29-68) | 37 (25-54) | 50 (33-70) | 66 (35-82) |
| Serum albumin, g/dLc | ||||
| <3.0 | 281 (15) | 185 (34) | 80 (7) | 16 (8) |
| 3.0-3.99 | 436 (23) | 192 (35) | 217 (19) | 27 (14) |
| ≥4.0 | 1152 (62) | 166 (31) | 834 (74) | 152 (78) |
| BUN, mg/dLc | ||||
| <17 | 472 (25) | 91 (17) | 318 (28) | 63 (32) |
| 17-25 | 499 (27) | 103 (19) | 334 (30) | 62 (32) |
| >25-39 | 448 (24) | 138 (25) | 275 (24) | 35 (18) |
| >39 | 450 (24) | 211 (39) | 204 (18) | 35 (18) |
| Hemoglobin, g/dLc | ||||
| <10.0 | 541 (29) | 289 (53) | 214 (19) | 38 (20) |
| 10.0-11.9 | 497 (27) | 142 (26) | 295 (26) | 60 (31) |
| ≥12.0 | 831 (45) | 112 (21) | 622 (55) | 97 (50) |
Abbreviations: ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); BUN, blood urea nitrogen; CAD, coronary artery disease; CKD, chronic kidney disease; eGFR, estimated glomerular filtration rate; eGFRcr, serum creatinine–based eGFR; eGFRcr-cys, eGFR using the Chronic Kidney Disease Epidemiology Collaboration race-free combined (serum creatinine and cystatin C) equation; eGFRcys, cystatin C–based eGFR.
SI conversion factor: To convert BUN to millimoles per liter, multiply by 0.357; hemoglobin to grams per liter, multiply by 10.0; serum albumin to grams per liter, multiply by 10; and serum creatinine to micromoles per liter, multiply by 88.4.
Race and ethnicity were self-identified by patients and obtained from Mass General Brigham’s centralized data warehouse.
Other included Alaskan Indian or American Indian, Hawaiian Native, declined to answer, and not recorded.
Data were missing for the following: BMI was missing for 433 participants (23%), serum albumin level was missing for 62 participants (3%), hemoglobin level was missing for 43 participants (2%), and BUN level was missing for 1 participant (0.05%). The remaining data were complete.
Chronic kidney disease was staged using the eGFRcr-cys.