Sagittal Abdominal Diameter, Waist Circumference, and BMI as Predictors of Multiple Measures of Glucose Metabolism: An NHANES Investigation of US Adults

Table 6

Shared variance between the anthropometric variables and the glucose metabolism variables by age category.

Metabolic measure	SAD			Waist circumference			BMI
	R^2	F	P	R^2	F	P	R^2	F	P
20–39 years ()
OGTT
Model 1	0.089^a	125.5	0.0001	0.080^a	98.2	0.0001	0.081^a	94.2	0.0001
Model 2	0.092^a	126.7	0.0001	0.080^b	92.7	0.0001	0.079^b	89.9	0.0001
Model 3	0.011^a	12.3	0.0014	0.000^b	0.5	0.4835	0.000^b	0.1	0.7204
Fasting glucose
Model 1	0.145^a	169.7	0.0001	0.135^a	128.9	0.0001	0.103^b	123.8	0.0001
Model 2	0.121^a	137.6	0.0001	0.114^a	105.3	0.0001	0.101^b	108.1	0.0001
Model 3	0.010^a	12.6	0.0012	0.001^b	2.1	0.1532	0.001^b	2.2	0.1474
HbA1c
Model 1	0.071^a	56.9	0.0001	0.062^b	52.1	0.0001	0.055^b	43.2	0.0001
Model 2	0.052^a	38.7	0.0001	0.050^a	38.6	0.0001	0.045^a	33.5	0.0001
Model 3	0.003^a	2.3	0.1367	0.001^b	0.9	0.3592	0.000^c	0.4	0.5333
HOMA-IR
Model 1	0.429^a	821.3	0.0001	0.404^b	589.8	0.0001	0.384^c	705.6	0.0001
Model 2	0.441^a	1348.7	0.0001	0.417^b	917.3	0.0001	0.383^c	959.0	0.0001
Model 3	0.027^a	58.4	0.0001	0.003^b	9.1	0.0049	0.001^c	2.0	0.1703
40–59 years ()
OGTT
Model 1	0.067^a	59.1	0.0001	0.049^b	37.2	0.0001	0.049^b	37.7	0.0001
Model 2	0.078^a	59.3	0.0001	0.059^b	43.0	0.0001	0.052^b	41.5	0.0001
Model 3	0.024^a	30.4	0.0001	0.002^b	1.6	0.2148	0.001^b	1.2	0.2775
Fasting glucose
Model 1	0.115^a	124.0	0.0001	0.100^b	114.1	0.0001	0.070^c	75.6	0.0001
Model 2	0.101^a	128.1	0.0001	0.087^b	117.3	0.0001	0.078^b	93.7	0.0001
Model 3	0.014^a	16.7	0.0003	0.000^b	0.0	0.8585	0.000^b	0.3	0.5693
HbA1c
Model 1	0.070^a	72.0	0.0001	0.055^b	57.5	0.0001	0.050^b	42.3	0.0001
Model 2	0.069^a	68.7	0.0001	0.059^b	64.7	0.0001	0.049^b	45.8	0.0001
Model 3	0.011^a	12.5	0.0013	0.000^b	0.0	0.8751	0.001^c	1.9	0.1837
HOMA-IR
Model 1	0.411^a	344.9	0.0001	0.381^b	244.5	0.0001	0.349^c	221.1	0.0001
Model 2	0.415^a	341.9	0.0001	0.380^b	247.6	0.0001	0.351^c	226.7	0.0001
Model 3	0.031^a	29.2	0.0001	0.000^b	0.4	0.5168	0.000^b	0.2	0.6405
60–84 years ()
OGTT
Model 1	0.069^a,c	18.9	0.0001	0.050^b	15.6	0.0004	0.063^c	22.2	0.0001
Model 2	0.090^a	21.3	0.0001	0.081^a	25.4	0.0001	0.082^a	26.2	0.0001
Model 3	0.005^a	1.7	0.2053	0.000^b	0.0	0.8875	0.002^c	1.2	0.2732
Fasting glucose
Model 1	0.127^a	14.6	0.0006	0.117^a	13.4	0.0009	0.111^a	12.9	0.0011
Model 2	0.124^a	15.2	0.0005	0.115^a	13.9	0.0007	0.122^a	14.0	0.0007
Model 3	0.004^a	2.8	0.1035	0.000^b	0.0	0.9111	0.004^a	3.2	0.0834
HbA1c
Model 1	0.062^a,c	13.3	0.0009	0.033^b	5.7	0.0229	0.054^c	11.1	0.0022
Model 2	0.073^a,c	17.5	0.0002	0.049^b	9.3	0.0047	0.062^c	12.2	0.0014
Model 3	0.021^a	12.8	0.0011	0.010^b	4.6	0.0407	0.002^c	1.6	0.2227
HOMA-IR
Model 1	0.445^a	265.6	0.0001	0.407^b	271.1	0.0001	0.396^b	173.0	0.0001
Model 2	0.442^a	261.6	0.0001	0.415^b	274.9	0.0001	0.401^b	185.8	0.0001
Model 3	0.021^a	30.8	0.0001	0.002^b	2.1	0.1545	0.003^b	1.8	0.1913

R² includes only the shared variance between the metabolic measure and the anthropometric variable. Variance from the covariates is not included. Model 1: includes no covariates. Model 2: adjusted for gender and race. Model 3: adjusted for gender, race, and the remaining two anthropometric variables. For example, Model 3 for OGTT and SAD adjusts for gender, race, waist circumference, and BMI. ^a,b,cR² values on the same row with the same superscript letter do not differ significantly ().