Table 1.
Baseline characteristics of participants in the VITAL-DKD trial
| Characteristic | All participants |
Vitamin D3 | n-3 fatty acids | |||||
|---|---|---|---|---|---|---|---|---|
| Active | Placebo | Active | Placebo | |||||
| N | 1312 | 703 | 609 | 659 | 653 | |||
| Demographics | ||||||||
| Female sex | 609 (46) | 327 (47) | 282 (46) | 315 (48) | 294 (45) | |||
| Age, years | 67.6 (6.9) | 67.4 (7.0) | 67.8 (6.8) | 67.7 (7.0) | 67.4 (6.8) | |||
| Race & ethnicity (N=1284) | ||||||||
| Non-Hispanic white | 857 (67) | 451 (66) | 406 (68) | 439 (68) | 418 (65) | |||
| Black | 278 (22) | 148 (22) | 130 (22) | 132 (20) | 146 (23) | |||
| Hispanic | 75 (6) | 41 (6) | 34 (6) | 36 (6) | 39 (6) | |||
| Asian/Pacific Islander | 35 (3) | 21 (3) | 14 (2) | 20 (3) | 15 (2) | |||
| American Indian/Alaskan Native | 13 (1) | 10 (1) | 3 (1) | 7 (1) | 6 (1) | |||
| Greater than high school education | 1099 (84) | 586 (83) | 513 (84) | 546 (83) | 553 (85) | |||
| Medical history and lifestyle | ||||||||
| Duration of diabetes, years | ||||||||
| <1 | 42 (3) | 28 (4) | 14 (2) | 18 (3) | 24 (4) | |||
| 1-2 | 177 (14) | 95 (14) | 82 (14) | 97 (15) | 80 (12) | |||
| 3-5 | 290 (22) | 150 (21) | 140 (23) | 140 (21) | 150 (23) | |||
| 6-10 | 360 (28) | 190 (27) | 170 (28) | 181 (28) | 179 (27) | |||
| 11-20 | 315 (24) | 172 (25) | 143 (24) | 159 (24) | 156 (24) | |||
| >20 | 124 (9) | 66 (9) | 58 (10) | 62 (9) | 62 (10) | |||
| Current smoking | 79 (6) | 39 (6) | 40 (7) | 37 (6) | 42 (7) | |||
| Current alcohol usea | 694 (54) | 375 (54) | 319 (54) | 342 (53) | 352 (55) | |||
| Medication and supplement use at randomisation | ||||||||
| Glucose-lowering medications | ||||||||
| Biguanides | 889 (68) | 469 (67) | 420 (69) | 446 (68) | 443 (68) | |||
| Sulfonylureas | 393 (30) | 209 (30) | 184 (30) | 194 (29) | 199 (30) | |||
| Insulin | 258 (20) | 135 (19) | 123 (20) | 124 (19) | 134 (21) | |||
| Thiazolidinediones | 124 (9) | 64 (9) | 60 (10) | 56 (8) | 68 (10) | |||
| DPP-4 inhibitors | 115 (9) | 59 (8) | 56 (9) | 55 (8) | 60 (9) | |||
| GLP-1 receptor agonists | 48 (4) | 23 (3) | 25 (4) | 25 (4) | 23 (4) | |||
| Antihypertensive medications | 1045 (80) | 556 (80) | 489 (81) | 524 (80) | 521 (81) | |||
| Number of classes | 1.4 (1.2) | 1.4 (1.2) | 1.4 (1.1) | 1.4 (1.2) | 1.4 (1.1) | |||
| ACEi or ARB | 803 (61) | 428 (61) | 375 (62) | 400 (61) | 403 (62) | |||
| ACEis | 565 (43) | 311 (44) | 254 (42) | 284 (43) | 281 (43) | |||
| Diuretics | 364 (28) | 198 (28) | 166 (27) | 193 (29) | 171 (26) | |||
| β-blockers | 295 (22) | 165 (23) | 130 (21) | 153 (23) | 142 (22) | |||
| Calcium channel blockers | 275 (21) | 151 (21) | 124 (20) | 133 (20) | 142 (22) | |||
| ARBs | 260 (20) | 131 (19) | 129 (21) | 127 (19) | 133 (20) | |||
| Mineralocorticoid receptor antagonists | 9 (1) | 5 (1) | 4 (1) | 2 (0) | 7 (1) | |||
| Cholesterol-lowering medication | 910 (71) | 488 (71) | 422 (71) | 449 (70) | 461 (72) | |||
| Supplemental vitamin D (≤800 IU/day) at randomisation | 536 (41) | 284 (40) | 252 (41) | 270 (41) | 266 (41) | |||
| Supplemental calcium (≤1200 mg/day) at randomisation | 312 (24) | 150 (21) | 162 (27) | 165 (25) | 147 (23) | |||
| Physical characteristics | ||||||||
| BMI, kg/m2 | 31.4 (6.7) | 31.6 (6.5) | 31.2 (7.0) | 31.1 (6.5) | 31.7 (6.9) | |||
| Laboratory values at baseline | ||||||||
| Serum creatinine (μmol/l) | 75.8 (23.8) | 76.2 (25.3) | 75.3 (21.9) | 75.0 (23.4) | 76.6 (24.1) | |||
| Cystatin C (mg/l) | 0.9 (0.3) | 0.9 (0.3) | 0.9 (0.3) | 0.9 (0.3) | 0.9 (0.3) | |||
| Baseline eGFR (ml min−1 1.73 m−2) | 85.8 (22.1) | 86.3 (22.8) | 85.3 (21.3) | 85.7 (21.3) | 86.0 (22.9) | |||
| UACR (mg/mmol Cr) | 0.34 (0.06-0.83) | 0.32 (0.06-0.93) | 0.35 (0.07-0.79) | 0.33 (0.06-0.83) | 0.34 (0.06-0.83) | |||
| 25(OH)D (nmol/l) | 74.1 (25.4) | 73.1 (25.5) | 75.2 (25.3) | 74.5 (26.2) | 73.7 (24.6) | |||
| <50 nmol/l | 226 (18) | 128 (19) | 98 (17) | 117 (19) | 109 (17) | |||
| 50 to <75 nmol/l | 456 (36) | 244 (36) | 212 (36) | 210 (33) | 246 (39) | |||
| ≥75 nmol/l | 575 (46) | 300 (45) | 275 (47) | 302 (48) | 273 (43) | |||
Entries are mean (SD) for continuous variables and n (%) for categorical variables. For UACR, median (IQR) is listed. Percentages are calculated as percentage of non-missing responses
a
Daily, weekly or monthly use of alcohol
DPP-4, dipeptidyl peptidase-4; GLP-1, glucagon-like peptide-1