Table 1

Characteristics of SEARCH participants according to autoimmunity and insulin sensitivity status

AutoimmuneNonautoimmune
ISIRPISIRP
N (%)1,248 (54.5)446 (19.5)232 (10.1)365 (15.9)
Clinical diabetes type, N (%)< 0.001<0.001
 Type 1 diabetes1,238 (99.2)412 (92.4)207 (89.2)86 (23.6)
 Type 2 diabetes/other10 (0.8)34 (7.6)25 (10.8)279 (76.4)
HLA risk category, N (%)*0.12<0.001
 Susceptible547 (43.8)173 (38.8)57 (24.6)33 (9.0)
 Neutral567 (45.4)232 (52.0)130 (56.0)236 (64.7)
 Protective23 (1.8)8 (1.8)15 (6.5)53 (14.5)
Insulin deficiency (FCP <0.4 ng/mL), N (%)487 (39.0)141 (31.6)0.00575 (32.3)15 (4.1)<0.001
Demographic characteristics
 NHW, N (%)979 (78.4)308 (69.1)<0.001172 (74.1)97 (26.6)<0.001
 Onset age (years)9.3 ± 3.712.9 ± 2.8<0.0019.4 ± 4.113.9 ± 2.6<0.001
 Onset age <10 years, N (%)660 (52.9)49 (11.0)<0.001117 (50.4)17 (4.7)<0.001
 Current age (years)10.4 ± 3.714.2 ± 2.9<0.00110.5 ± 4.115.1 ± 2.7<0.001
 Diabetes duration (months)9.6 ± 5.911.5 ± 6.6<0.00110.0 ± 6.211.3 ± 6.90.03
 Male, N (%)646 (51.8)218 (48.9)0.30130 (56.0)137 (37.5)<0.001
 Family history of diabetes, N (%)*155 (15.9)74 (21.8)0.01441 (22.9)155 (52.5)<0.001
Clinical characteristics
 BMI z score*0.4 ± 0.91.2 ± 0.9<0.0010.2 ± 1.02 ± 0.8<0.001
 BMI percentiles, N (%)*<0.001<0.001
  <85961 (77.3)161 (36.3)179 (78.5)35 (9.7)
  85–95197 (15.8)134 (30.2)34 (14.9)46 (12.7)
  ≥9585 (6.8)149 (33.6)15 (6.6)281(77.6)
 Waist (cm)67.7 ± 0.383.0 ± 0.5<0.00171.7 ± 1.1103.1 ± 0.9<0.001
 Acanthosis, N (%)*27 (2.2)51 (11.8)<0.0019 (3.9)221(62.6)<0.001
 Insulin use, N (%)*1,228 (98.6)422 (94.6)<0.001210 (91.3)207 (56.9)<0.001
 DKA at onset, N (%)*270 (29.1)98 (29.9)0.7939 (23.1)36 (13.1)0.007
Biochemical characteristics
 FCP (ng/mL), median (25th–75th)0.5 (0.2–0.9)0.7 (0.3–1.4)<0.0010.6 (0.3–1.2)3.4 (1.9–4.8)<0.001
 IS score11.9 ± 2.46.3 ± 1.5<0.00112.2 ± 3.04.5 ± 1.8<0.001
 GADA-positive, N (%)859 (68.8)327 (73.3)0.08N/A
 GADA titers, median (25th–75th)103.4 (16.3–418.5)106.6 (26.2–397.4)0.450 (0–8.2)0 (0–0)N/A
 IA-2A positive, N (%)1,032 (82.7)351 (78.7)0.06N/A
 IA-2A titers, median (25th–75th)233.3 (29.7–438.3)290.7 (13.5–452.5)0.500 (0–0)0 (0–0)N/A
 GADA and IA-2A positive, median (25th–75th)643 (51.5)232 (52.0)0.86N/A
  • Data are means ± SD unless otherwise noted. P for associations between IR and IS within each autoimmunity category. N/A, not applicable.

  • *Missing values.

  • †Adjusted for age and sex.