Online Supplemental Tables

Online Supplemental Tables:

Table 1: Visit 1 characteristics of African American ARIC participants

Controls
(N=1150) / All Diabetic Cases
(N=591)
Age (yrs) / 53.1 / 54.0
Gender (%Male) / 38 / 32
BMI (kg/m2)* / 28.45 / 31.88
Waist-to-hip ratio* / 0.903 / 0.950
Glucose (mM)** / 5.40 / 5.90
In (insulin, pM)** / 4.33 / 4.72
Waist Circumference (cm)* / 95.6 / 105.8
Has at least one parent with DM (%) / 23 / 36
Age of DM diagnosis (yrs) † / -- / 51.6

Differences between cases and controls all statistically significant (p < 0.01)

*Based on 1149 controls and 590 cases (prevalent and incident diabetic cases are pooled).

**Based on baseline values for 1113 controls and 249 incident DM cases.

† Based on self-report of 275 cases.

Online Supplement

Table 2. Relative hazards (RH) for incident T2DM in 1402 African American ARIC participants by obesity status at Visit 1

InsCCG243 Genotype
D/D / I/D / I/I
Visit 1 BMI < 25 kg/m2
Controls (N =309) / 249 / 55 / 5
Incident T2DM (N = 28) / 27 / 1 / 0
RH*
(95% CI) / 1.00
(reference) / 0.25
(0.03, 1.85) / ___
25 kg/m2  Visit 1 BMI 30 kg/m2
Controls (N=465) / 403 / 59 / 3
Incident T2DM (n=90) / 69 / 20 / 1
OR*
(95% CI) / 1.00
(reference) / 1.81
(1.01, 2.98) / 1.94
(0.26, 14.27)
Visit 1 BMI ≥ 30 kg/m2
Controls (N=376) / 312 / 59 / 5
Incident T2DM (n=134) / 110 / 21 / 3
OR*
(95% CI) / 1.00
(reference) / 1.07
(0.67, 1.70) / 1.30
(0.41, 4.12)

*Adjusted for age at Visit 1 and sex

Online Supplement

Table 3 Pre-diabetic (Visit 1) characteristics of 224 ARIC participants with incident T2DM and visit 1 BMI ≥ 25 kg/m2 by InsCCG243 genotype

InsCCG243 Genotype
Characteristic / D/D
(n=179) / I/D
(n=41) / I/I
(n=4) / p
BMI at age 25 (kg/m2) / 23.54 / 23.97 / 23.94 / 0.84
BMI (kg/m2) / 32.63 / 32.22 / 30.72 / 0.75
Waist-to-Hip ratio / 0.945 / 0.927 / 0.935 / 0.22
Waist circumference (cm) / 106.53 / 104.49 / 101.68 / 0.56
Glucose (mM)† / 5.92 / 5.94 / 5.43 / 0.22
ln (insulin, pM)† / 4.79 / 4.76 / 4.84 / 0.91
Glucose/Insulin (mg/dl / uU/ml) † / 7.26 / 8.03 / 6.14 / 0.54
ln(HOMA-%B)† / 4.96 / 4.92 / 5.25 / 0.53
ln (HOMA-IR)† / 1.48 / 1.45 / 1.44 / 0.94
ln(HOMA-%B)†* / 4.96 / 4.93 / 5.31 / 0.38
ln (HOMA-IR)†* / 1.48 / 1.46 / 1.52 / 0.97
Age at diagnosis / 55.6 / 58.5 / 55.5
Insulin use (%)* / 9 / 7 / 0 / 0.78

All mean values adjusted for age at Visit 1 and sex

†Based on 178 (D/D), 41 (I/D ) and 4 (I/I) individuals

* Further adjusted for BMI at Visit 1