Table. Distribution of Participant Characteristics by Treatment Group and Strata.
| Participant Characteristicsa | Entire Cohort | Primary Stratum | Secondary Stratum 1 | Secondary Strata 2 and 3 | ||||
|---|---|---|---|---|---|---|---|---|
| Oral Insulin (n = 283) |
Placebo (n = 277) |
Oral Insulin (n = 203) |
Placebo (n = 186) |
Oral Insulin (n = 28) |
Placebo (n = 27) |
Oral Insulin (n = 52) |
Placebo (n = 64) |
|
| Age, median (IQR), y | 8.2 (5.9-12.5) |
8.2 (5.4-11.5) |
8.6 (6.1 -12.8) |
8.2 (5.5-11.8) |
9.1 (5.9-13.7) |
8.5 (6.5-10.8) |
7.3 (5.1 -10.3) |
8.3 (5.1-11.5) |
| Boys, No. (%) | 170 (60.1) | 170 (61.4) | 128 (63.1) | 117 (62.9) | 19 (67.9) | 19 (70.4) | 23 (44.2) | 34 (53.1) |
| Race/ethnicity, No. (%)b | ||||||||
| White | 252 (95.5) | 249 (94.3) | 181 (95.3) | 172 (94.5) | 25 (96.2) | 25 (100.0) | 46 (95.8) | 52 (91.2) |
| Black | 8 (3.0) | 9 (3.4) | 6 (3.2) | 4 (2.2) | 0 | 0 | 2 (4.2) | 5 (8.8) |
| Asian/Pacific Islander | 4 (1.5) | 6 (2.3) | 3 (1.6) | 6 (3.3) | 1 (3.8) | 0 | 0 | 0 |
| Non-Hispanic, No. (%) | 256 (90.5) | 252 (91.0) | 182 (89.7) | 171 (91.9) | 26 (92.9) | 26 (96.3) | 48 (92.3) | 55 (85.9) |
| BMI, median (IQR)c | 17.1 (15.3-19.5) |
16.9 (15.5-19.2) |
17.4 (15.5-20.0) |
17.1 (15.6-19.6) |
16.2 (15-18.1) |
16.9 (15.5-17.8) |
16.4 (15.0-18.4) |
16.8 (15.3-19.2) |
| Family members with type 1 diabetes, No. (%) | ||||||||
| Sibling | 153 (54.1) | 162 (58.5) | 110 (54.2) | 111 (59.7) | 15 (53.6) | 19 (70.4) | 28 (53.8) | 32 (50.0) |
| Identical twin | 6 (2.1) | 3 (1.1) | 3 (1.5) | 2 (1.1) | 2 (7.1) | 1 (3.7) | 1 (1.9) | 0 |
| Offspring | 3 (1.1) | 7 (2.5) | 2 (1.0) | 5 (2.7) | 0 | 0 | 1 (1.9) | 2 (3.1) |
| Parent | 71 (25.1) | 57 (20.6) | 45 (22.2) | 40 (21.5) | 7 (25.0) | 3 (11.1) | 19 (36.5) | 14 (21.9) |
| Parent and sibling | 10 (3.5) | 13 (4.7) | 9 (4.4) | 6 (3.2) | 1 (3.6) | 3 (11.1) | 0 | 4 (6.2) |
| Offspring and another first-degree relative | 2 (0.7) | 0 | 2 (1.0) | 0 | 0 | 0 | 0 | 0 |
| Second-degree relative | 33 (11.7) | 30 (10.8) | 27 (13.3) | 18 (9.7) | 3 (10.7) | 1 (3.7) | 3 (5.8) | 11 (17.2) |
| Third-degree or further removed relative | 5 (1.8) | 5 (1.8) | 5 (2.5) | 4 (2.2) | 0 | 0 | 0 | 1 (1.6) |
| Autoantibodies positive, No. (%) | ||||||||
| Glutamic acid decarboxylase | 235 (83.0) | 236 (85.2) | 171 (84.2) | 156 (83.9) | 21 (75.0) | 23 (85.2) | 43 (82.7) | 57 (89.1) |
| Insulinoma-associated antigen-2 | 157 (55.5) | 146 (52.7) | 131 (64.5) | 126 (67.7) | 20 (71.4) | 18 (66.7) | 6 (11.5) | 2 (3.1) |
| Micro insulin autoantibodies | 253 (89.4) | 241 (87.0) | 186 (91.6) | 163 (87.6) | 24 (85.7) | 24 (88.9) | 43 (82.7) | 54 (84.4) |
| Islet cell autoantibodies | 198 (70.0) | 178 (64.3) | 171 (84.2) | 152 (81.7) | 25 (89.3) | 22 (81.5) | 2 (3.8) | 4 (6.2) |
| Hemoglobin A1c, median (IQR), %d | 5.0 (4.8-5.2) |
5.1 (4.8-5.2) |
5.0 (4.8-5.2) |
5.1 (4.8-5.2) |
5.1 (4.9-5.3) |
5.2 (5.0-5.5) |
5.0 (4.9-5.2) |
5.0 (4.9-5.1) |
| First-phase insulin release, median (IQR), μU/mL | 145 (102-221) |
150 (98.4-232) |
153 (112-230) |
152 (106-236) |
50.8 (45.4-67.1) |
57.8 (44.8-71.9) |
163 (119-243) |
174 (132-285) |
| C-peptide, median (IQR), nmol/Le | 1.35 (1.00-1.81) |
1.34 (1.03-1.82) |
1.42 (1.04-1.91) |
1.34 (1.04-1.96) |
1.02 (0.93 -1.3) |
1.1 (0.76-1.52) |
1.36 (1.06-1.75) |
1.43 (1.11-1.8) |
| Human leukocyte antigen alleles, No.(%)f | ||||||||
| DR3 | 119 (42.2) | 102 (37.0) | 88 (43.3) | 74 (39.8) | 9 (32.1) | 9 (33.3) | 22 (43.1) | 19 (30.2) |
| DR4 | 199 (70.6) | 182 (65.9) | 144 (70.9) | 135 (72.6) | 22 (78.6) | 18 (66.7) | 33 (64.7) | 29 (46.0) |
Abbreviations: BMI, body mass index, calculated as weight in kilograms divided by height in meters squared; IQR, interquartile range.
The primary stratum included participants with normal glucose tolerance, first-phase insulin release higher than threshold, the presence of microinsulin autoantibodies, and islet cell autoantibodies on 2 separate samples or both glutamic acid decarboxylase and insulinoma-associated antigen-2 autoantibodies on the same sample. Secondary stratum 1 included participants with the same profile as those in the primary stratum except they had first-phase insulin release that was lower than threshold. Secondary stratum 2 participants had normal glucose tolerance, first-phase insulin release higher than threshold, the presence of microinsulin autoantibodies, and islet cell autoantibodies on 1 sample or glutamic acid decarboxylase or insulinoma-associated antigen-2 autoantibodies on 2 separate samples. Secondary stratum 3 included participants whose profiles were identical to those in secondary stratum 2 except for their first-phase insulin release was lower than threshold, defined in the Methods section.
Self-reported race was not provided by 32 participants.
Not reported for 3 participants.
Values were missing for 1 participant.
C-peptide from oral glucose tolerance test not available for 1 participant. Area under the curve (AUC) mean, oral glucose tolerance test.
Not available for 2 participants.