Table 1.

Characteristics of Subjects Including Environmental Measures and Heritabilities for Cardiometabolic Risk Factors in 617^a SAFARI Children

Trait*	Na	Mean ± SD or %	Definitions/Normal Thresholds	Heritability h2± S.E	p-value b	Variance explained by covariates (%)
Girls	617	48.8%	-	-	-	-
Age	617	11.7 ± 3.5	-	-	-	-
Overweight	617	53.8%	BMI ≥85 and <95th percentile	-	-	-
Obese	617	33.7%	BMI ≥95 and <99th percentile	-	-	-
Pre-diabetes	617	13.3%	FPG ≥100 and <126 mg/dl	-	-	-
Metabolic Syndromec	617	18.6%	< 3 components of the 6 examined components	-	-	-
Harvard Physical Fitness Score (HPFS)	474	59.1 ± 24.8	> 96 excellent score	-	-	-
Sedentary Activity_Usual	606	0.67 ± 0.35	5 categories of time spent: 0 – 3hrs	-	-	-
Sedentary Activity_Yesterday	617	0.51 ± 0.31	5 categories of time spent: 0 – 3hrs	-	-	-
Body mass Index [BMI(kg/m2)]d	616	22.9 ± 6.4	BMI values at 6 &17 yearsf:	0.79 ± 0.12	5.1 × 10−11	0.26
			Boys:16.9±0.26; 24.9± 0.70
			Girls:16.0±0.25; 23.9 ±0.56
Waist Circumference (WC, mm)d	615	773.0 ± 180.4	WC values at 6 & 17 yearsf:	0.67 ± 0.12	2.5 × 10−8	0.36
			Boys:57.4±0.74; 85.6±1.82
			Girls:56.5±0.60; 82.2±1.50
Fat Mass (Kg)d	615	14.4 ± 15.9	Boys: 28–23% g	0.57 ± 0.12	3.0 × 10−7	0.36
			Girls: 31–35%
Fasting Glucose (mg/dl)d	609	89.6 ± 7.1	< 100 mg/dl	0.43 ± 0.12	5.2 × 10−5	0.02
Fasting Insulin (µIU/ml)d	600	13.0 ± 7.2	≤16.25 uIU/ml	0.64 ± 0.12	1.8 × 10−8	0.12
HOMA-IRe	599	1.9 ± 1.0	< 3 h	0.63 ± 0.12	1.0 × 10−7	0.11
HDL (mg/dl)d	605	45.5 ± 10.5	> 45 mg/dli	0.62 ± 0.12	2.0 × 10−7	0.06
TG (mg/dl)d	602	73.6 ± 35.7	<75 mg/dl (0 to 9 yrs)i	0.75 ± 0.12	2.0 × 10−10	0.04
			<90 mg/dl (10–19 yrs)i
SBP (mmHg)d	617	104.3 ± 9.7	BP <120/80 mmHg j	0.70 ± 0.11	1.0 × 10−10	0.20
DBP (mmHg)d	617	63.1 ± 7.0	BP <120/80 mmHg j	0.58 ± 0.11	1.0 × 10−7	0.08
Metabolic Syndrome Risk Score (# of MS Components (MSC)	617	1.28 ± 1.36	risk score range: 0–5	0.58 ± 0.13	3.2 × 10−6	0.05

^aSample sizes for CMRFs varied from 599 (HOMA-IR) to 617 (MSC) based on availability of data and exclusion of outliers (i.e., values ± 4 SD from the mean were excluded from genetic analysis); Sample sizes for environmental variables ranged from 474 (Harvard fitness scores) to 617 (sedentary activity_ yesterday);

^bFrom likelihood ratio tests of models with the additive genetic variance estimated and constrained to 0;

^cAs defined in Fowler et al. 2013;

^*CMRF definitions and descriptions were provided in Fowler et al. 2013;

^fBMI and WC (cm) Reference value ranges (mean ± Standard Error of the Mean[SEM]) for boys and girls at 6 and 17 years of age (Fryar, Gu, & Ogden, 2012);

^dTraits were inverse-normalized for genetic analyses;

^ehomeostasis model of assessment-insulin resistance.

^g(C. L. Ogden, Li, Freedman, Borrud, & Flegal, 2011);

^h(Keskin, Kurtoglu, Kendirci, Atabek, & Yazici, 2005);

ⁱ(Hauk, 2012);

^j(Chow et al., 2010).