Table 1.
Characteristics of 2,789 SEARCH antibody-positive participants by preserved β-cell function status as defined by fasting C-peptide levels
| Entire cohort | β-Cell function |
||||
|---|---|---|---|---|---|
| DCCT |
NHANES 5th percentile |
||||
| Preserved (FCP ≥0.23 ng/ml) | Not preserved (FCP <0.23 ng/ml) | Preserved (FCP ≥1.0 ng/ml) | Not preserved (FCP <1.0 ng/ml) | ||
| n (%) | 2,789 | 1,329 (47.7) | 1,460 (52.4) | 406 (14.6) | 2,383 (85.4) |
| Sex | |||||
| Male | 1,385 (49.7) | 682 (49.2) | 703 (50.8) | 210 (15.2) | 1,175 (84.4) |
| Female | 1,404 (50.3) | 647 (46.1) | 757 (53.9) | 196 (14.0) | 1,208 (86.0) |
| Race/ethnicity | |||||
| Non-Hispanic white | 2,103 (75.4) | 9,781 (46.5) | 1,125 (53.5) | 288 (13.7) | 1,815 (86.3) |
| Other | 686 (24.6) | 351 (51.2) | 335 (48.8) | 118 (17.2) | 568 (82.8) |
| HLA DR* | |||||
| 03/04 | 1,781 (90.5) | 716 (40.2) | 1,065 (59.8) | 221 (12.4) | 1,560 (87.6) |
| 15 | 35 (1.8) | 23 (65.7) | 12 (34.3) | 10 (28.6) | 25 (71.4) |
| Other | 152 (7.7) | 62 (40.8) | 90 (59.2) | 18 (11.8) | 134 (88.2) |
| No. of autoantibodies | |||||
| 2 | 1,172 (42.0) | 647 (55.2) | 525 (44.8) | 210 (17.9) | 962 (82.1) |
| 1 | 1,617 (58.0) | 682 (42.2) | 935 (57.8) | 196 (12.1) | 1,421 (87.9) |
| Age at diagnosis (years) | 9.0 (0–19) | 10.5 (1–19) | 7.6 (0–18) | 12.6 (3.0–18.0) | 8.9 (0–19.0) |
| Age at visit (years) | 12.4 (1.5–22.7) | 12.3 (1.9–22.5) | 12.5 (1.5–22.7) | 13.8 (4.0–21.8) | 12.4 (1.5–22.7) |
| Duration of diabetes (months) | 35.8 (0–213) | 16.1 (0–210) | 53.7 (0–213) | 8.8 (0–47) | 36.8 (0–213) |
| BMI Z score | 0.6 (−4.2 to 4.7) | 0.7 (−4.2 to 3.1) | 0.6 (−3.3 to 4.7) | 1.6 (−2.0 to 3.0) | 0.6 (−4.2 to 4.7) |
| A1C (%) | 8.1 (3.1–17.9) | 7.7 (3.1–17.3) | 8.5 (5.3–17.9) | 6.9 (4.8–13.0) | 8.1 (3.1–17.9) |
| Fasting glucose (mg/dl) | 191.2 (42–658) | 170.8 (42–518) | 209.8 (43–658) | 141.3 (79–330) | 192 (42–658) |
Data are n (%) or mean (range). For the column “Entire cohort,” percentages total to 100 vertically within each variable (sex, race/ethnicity, HLA, and autoantibody number). For the remaining columns, the percentages total to 100 horizontally between preserved and not preserved for each definition. All continuous variables were different between those with preserved and not preserved C-peptide (t test; P < 0.05), except age at visit and BMI Z score for DCCT cutoff. Race/ethnicity, number of autoantibodies, and HLA DR showed a significant association with preserved status (χ2, at P < 0.05).
*HLA was tested on a subset of subjects (n = 1,968). FCP, fasting C-peptide.