Table 1.
Baseline characteristics of the cohorts
| Full sample (N = 276,794) | 2021 temporal validation cohort (N = 169,678) | ||
|---|---|---|---|
| Derivation cohort (N = 249,148) | Internal validation cohort (N = 27,646) | ||
| Sex (%) | |||
| Female | 119,917 (48.1) | 13,323 (48.2) | 81,233 (47.9) |
| Male | 129,217 (51.9) | 14,323 (51.8) | 88,439 (52.1) |
| Other/unknown | 14 (0.0) | 0 (0.0) | 6 (0.0) |
| Race (%) | |||
| White | 101,891 (40.9) | 11,205 (40.5) | 113,096 (40.9) |
| Asian | 54,675 (21.9) | 6,185 (22.4) | 60,860 (22.0) |
| Black | 22,078 (8.9) | 2,459 (8.9) | 24,537 (8.9) |
| Hispanic | 52,747 (21.2) | 5,769 (20.9) | 58,516 (21.1) |
| Other | 17,757 (7.1) | 2,028 (7.3) | 19,785 (7.1) |
| Age in years at baseline | |||
| Mean (SD) | 60.0 (13.1) | 59.8 (13.2) | 64.1 (13.0) |
| Median [min, max] | 61.0 [18.0, 102] | 61.0 [18.0, 100] | 65.0 [18.0, 103] |
| Age in years at diabetes diagnosis | |||
| Mean (SD) | 55.9 (13.1) | 55.7 (13.2) | 54.0 (12.7) |
| Median [min, max] | 56.0 [0, 103] | 56.0 [1.00, 99.0] | 55.0 [0, 99.0] |
| Diabetes type (%) | |||
| 1 | 4,858 (1.9) | 569 (2.1) | 5,442 (3.2) |
| 2 | 221,742 (89.0) | 24,512 (88.7) | 162,537 (95.8) |
| Unknown | 22,548 (9.1) | 2,565 (9.3) | 1,699 (1.0) |
| BMI, kg/m2 | |||
| Mean (SD) | 31.8 (6.73) | 31.8 (6.72) | 31.2 (6.93) |
| Median [min, max] | 30.7 [10.6, 197] | 30.7 [14.5, 91.7] | 30.0 [10.4, 162] |
| Systolic blood pressure, mmHg | |||
| Mean (SD) | 127 (14.2) | 127 (14.2) | 129 (16.2) |
| Median [min, max] | 126 [55.0, 258] | 126 [69.0, 227] | 130 [50.0, 248] |
| Diastolic blood pressure, mmHg | |||
| Mean (SD) | 72.8 (9.82) | 72.8 (9.79) | 69.8 (11.8) |
| Median [min, max] | 73.0 [0, 173] | 73.0 [0, 132] | 70.0 [20.0, 148] |
| Hemoglobin A1C, % | |||
| Mean (SD) | 7.31 (1.63) | 7.35 (1.65) | 7.47 (1.57) |
| Median [min, max] | 6.80 [3.50, 22.4] | 6.80 [4.30, 19.7] | 7.10 [4.20, 20.0] |
| Urinary albumin creatinine ratio, mg/g | |||
| Mean (SD) | 19.6 (42.7) | 19.7 (43.5) | 45.4 (80.5) |
| Median [min, max] | 8.70 [0.200, 1,050] | 8.70 [0.200, 1,010] | 13.2 [0.700, 1,430] |
| Triglycerides, mg/dL | |||
| Mean (SD) | 173 (172) | 173 (159) | 172 (132) |
| Median [min, max] | 145 [22.0, 13,400] | 145 [24.0, 5,400] | 145 [17.0, 9,540] |
| LDL, mg/dL | |||
| Mean (SD) | 93.8 (31.8) | 93.9 (31.4) | 82.2 (33.2) |
| Median [min, max] | 89.0 [1.00, 1,360] | 89.0 [15.0, 338] | 77.0 [7.00, 968] |
| HDL, mg/dL | |||
| Mean (SD) | 45.8 (10.9) | 45.8 (10.8) | 47.4 (11.7) |
| Median [min, max] | 44.0 [4.00, 177] | 44.0 [5.00, 128] | 46.0 [4.00, 217] |
| Creatinine, mg/g | |||
| Mean (SD) | 0.913 (0.349) | 0.913 (0.356) | 1.00 (0.703) |
| Median [min, max] | 0.870 [0.0700, 15.3] | 0.870 [0.200, 14.0] | 0.890 [0.200, 20.8] |
| Smoking status (%) | |||
| Current smoker | 14,141 (5.7) | 1,551 (5.6) | 7,464 (4.4) |
| Former smoker | 52,285 (21.0) | 5,781 (20.9) | 49,719 (29.3) |
| Passive smoker | 1,427 (0.6) | 169 (0.6) | 654 (0.4) |
| Never smoker | 115,487 (46.4) | 12,933 (46.8) | 102,121 (60.2) |
| Unknown | 65,808 (26.4) | 7,212 (26.1) | 9,720 (5.7) |
| UACR stage (%) | |||
| Macroalbuminuria | 455 (0.2) | 60 (0.2) | 1,386 (0.8) |
| Microalbuminuria | 26,689 (10.7) | 2,964 (10.7) | 42,225 (24.9) |
| Missing | 105,139 (42.2) | 11,679 (42.2) | 26,489 (15.6) |
| Normal | 116,865 (46.9) | 12,943 (46.8) | 99,578 (58.7) |
| Chronic kidney disease stage number (%) | |||
| 1 | 97,620 (39.2) | 10,778 (39.0) | 64,265 (37.9) |
| 2 | 101,162 (40.6) | 11,328 (41.0) | 72,604 (42.8) |
| 3 | 26,500 (10.6) | 2,920 (10.6) | 25,614 (15.1) |
| 4 | 1,183 (0.5) | 134 (0.5) | 2,232 (1.3) |
| 5 | 336 (0.1) | 40 (0.1) | 1,524 (0.9) |
| Missing | 22,347 (9.0) | 2,446 (8.8) | 3,439 (2.0) |
| Diabetic neuropathy | 23,261 (9.3) | 2,488 (9.0) | 40,858 (24.1) |
| Diabetes medications (%)a | |||
| Metformin | 148,500 (59.6) | 16,482 (59.6) | 114,654 (67.6) |
| Sulfonylurea | 113,607 (45.6) | 12,635 (45.7) | 70,115 (41.3) |
| Insulin | 65,848 (26.4) | 7,388 (26.7) | 50,182 (29.6) |
| Thiazolidinediones | 23,512 (9.4) | 2,612 (9.4) | 7,564 (4.5) |
| Dipeptidyl peptidase 4 inhibitors | 4,355 (1.7) | 472 (1.7) | 3,048 (1.8) |
| Glucagon-like peptide-1 | 1,563 (0.6) | 191 (0.7) | 2,626 (1.5) |
| Sodium-glucose cotransporter-2 inhibitors | 1,481 (0.6) | 156 (0.6) | 9,258 (5.5) |
| Other | 1,263 (0.5) | 143 (0.5) | 278 (0.2) |
| None | 77,475 (31.1) | 8,559 (31.0) | 32,267 (19.0) |
| Positive outcomes (%) | |||
| PDR | 2,434 (1.0) | 279 (1.0) | 1,350 (0.8)b |
| refDR | 17,108 (6.9) | 1,970 (7.1) | 6,284 (4.2)c |
| DME | 7,404 (3.0) | 825 (3.0) | 1,828 (1.2)d |
For overall cohort, baseline is the date of visit when no DR is confirmed by fundus photograph; for 2021 cohort, baseline is 1 January 2021. All clinical inputs are last measurement prior to baseline. min, minimum value; max, maximum value.
a
Medication dispensed during 6 months prior to baseline;
b
n for validation cohort = 161,819;
c
n for validation cohort = 145,056;
d
n for validation cohort = 158,094.