Table 1.
Clinical and demographic features of individuals with type 1 diabetes diagnosed in the first 6 months of life
| Characteristic | Monogenic NDM (n = 164) | Diabetes diagnosed before 6 months of age | Type 1 diabetes diagnosed at 6–24 months of age (n = 152) | |
|---|---|---|---|---|
| Low T1D-GRS (n = 103) | High T1D-GRS (n = 63) | |||
| T1D-GRS | 0.233 (0.217, 0.245) (n = 115) | 0.241 (0.219, 0.252) | 0.298 (0.292, 0.304) | 0.294 (0.261, 0.310) (n = 102) |
| Age at diagnosis (weeks) | 9 (4, 15) | 4 (1, 12) | 16 (6, 21) | 48 (39, 56) |
| Birthweight z scorea | −1.39 (−2.04, −0.62) (n = 124) | −1.23 (−2.54, −0.17) (n = 81) | −0.89 (−1.96, −0.02) (n = 48) | −0.25 (−0.89, 0.59) (n = 125) |
| Female sex, n (%) | 86 (52) | 40 (39) | 27 (43) | 60 (40) |
| Related parents, n/n (%)b | 20/157 (13) | 24/100 (24) | 15/63 (24) | 12/89 (13) |
| First-degree relative with type 1 diabetes, n/n (%) | 1/152 (1) | 1/97 (1) | 10/61 (16) | 11/88 (13) |
| Mother with type 1 diabetes, n/n (%) | 0/152 (0) | 0/97 (0) | 1/61 (2) | 2/88 (2) |
| Father with type 1 diabetes, n/n (%) | 1/152 (1) | 0/97 (0) | 4/61 (7) | 3/88 (3) |
| Sibling with type 1 diabetes, n/n (%) | 0/152 (0) | 1/97 (1) | 6/61 (10) | 6/88 (7) |
| Insulin treated from diagnosis, n/n (%) | 164/164 (100) | 103/103 (100) | 63/63 (100) | 152/152 (100) |
| Insulin daily dose, U/kg | 0.77 (0.50, 1.00) (n = 125) | 0.63 (0.50, 1.00) (n = 81) | 0.81 (0.50, 1.00) (n = 48) | 0.78 (0.50, 1.00) (n = 64) |
| HbA1c, mmol/mol | 69 (56, 101) (n = 107) | 64 (44, 74) (n = 49) | 65 (58, 78) (n = 54) | 76 (62, 87) (n = 59) |
| HbA1c, % | 8.5 (7.3, 11.4) | 8.0 (6.2, 8.9) | 8.1 (7.5, 9.3) | 9.1 (7.8, 10.1) |
| Blood glucose at diagnosis, mmol/l | 30.7 (22.0, 38.9) (n = 114) | 28.0 (21.1, 39.2) (n = 80) | 30.0 (23.0, 38.1) (n = 52) | 27.7 (23.0, 36.1) (n = 59) |
| Duration of diabetes at sampling | 5.5 m (1.0 m, 8.2 y) | 1.5 m (0.7 m, 1.7 y) | 7.9 m (2.2 m, 5.3 y) | 2.9 y (1.5 m, 15.1 y) |
| Syndromic presentation, n (%) | 5 (3) | 28 (27) | 6 (9) | 1 (1) |
| Additional autoimmune condition, n (%) | 1 (1) | 7 (7) | 3 (4) | 15 (10) |
| Autoantibody positive, n/n (%) | ||||
| GADA/IA2A/ZnT8A | 7/93 (8) | 4/33 (12) | 9/22 (41) | 51/88 (58) |
| GADA | 2/93 (2) | 4/33 (12) | 6/22 (27) | 39/88 (44) |
| IA2A | 4/93 (4) | 0/33 (0) | 4/22 (16) | 13/88 (15) |
| ZnT8A | 1/93 (1) | 0/33 (0) | 3/22 (14) | 7/88 (8) |
| Age at antibody measurement | 26 w (13 w, 5.8 y) | 20 w (5 w, 9 y) | 3.7 y (4.6 m, 8.5 y) | 4 y (1 y, 17 y) |
| Duration of diabetes at antibody measurement | 11 w (3 w, 6 y) | 6 w (3 w, 9 y) | 3.0 y (2.3 m, 7.5 y) | 4.0 y (6 w, 14 y) |
| C-peptide, pmol/l | ||||
| Duration of diabetes <12 months | 64 (13, 138) (n = 61) | 117 (16, 362) (n = 15) | <3 (<3, 10) (n = 7) | 24.5 (<3, 67) (n = 26) |
| Duration of diabetes >12 months | 8.5 (<3, 40) (n = 50) | <3 (<3, 63) (n = 10) | <3 (<3, <3) (n = 12) | <3 (<3, <3) (n = 38) |
All data are median (IQR) unless otherwise specified
aBased on WHO international reference range, adjusted for sex and gestation period
bDefined as parents being second cousins or closer relatives
m, months; w, weeks; y, years