Association between body mass index and lumbar spine volumetric bone mineral density in diabetic and non-diabetic patients

Table 2 Saturation effect analysis of body mass index and volumetric bone mineral density

	Diabetes		Non-diabetes		Total
	β (95%CI)	P value	β (95%CI)	P value	β (95%CI)	P value
vBMD
Model 1
One line effect	0.54 (-0.20, 1.29)	0.155	0.40 (0.01, 0.78)	0.043	0.43 (0.09, 0.77)	0.014
Model 2
BMI turning point (K), kg/m2	29.24		21.48		21.42
< K, effect 1	0.28 (-0.81, 1.38)	0.612	3.84 (0.41, 7.26)	0.028	3.70 (0.33, 7.08)	0.032
> K, effect 2	1.12 (-0.83, 3.06)	0.261	0.21 (-0.22, 0.64)	0.339	0.28 (-0.09, 0.66)	0.139
Effect 2 - 1	0.83 (-1.77, 3.43)	0.532	-3.63 (-7.22, -0.04)	0.048	-3.42 (-6.93, 0.09)	0.056
LRT test		0.529		0.047		0.056
Men
Model 1
One line effect	0.33 (-0.86, 1.52)	0.589	0.53 (-0.08, 1.15)	0.043	0.49 (-0.06, 1.04)	0.080
Model 2
BMI turning point (K), kg/m2	26.45		22.33		21.65
< K, effect 1	1.07 (-1.26, 3.39)	0.370	3.51 (0.56, 6.46)	0.020	3.93 (0.14, 7.72)	0.042
> K, effect 2	-0.33 (-2.48, 1.82)	0.763	0.05 (-0.73, 0.82)	0.907	0.19 (-0.45, 0.83)	0.567
Effect 2 - 1	-1.40 (-5.18, 2.38)	0.470	-3.46 (-6.82, -0.11)	0.043	-3.74 (-7.82, 0.34)	0.072
LRT test		0.465		0.043		0.072
Women
Model 1
One line effect	0.7 (-0.2, 1.7)	0.133	0.4 (-0.1, 0.8)	0.143	0.49 (-0.06, 1.04)	0.080
Model 2
BMI turning point (K), kg/m2	27.3		28.7		29
< K, effect 1	-0.2 (-2.4, 2.0)	0.844	-0.1 (-0.8, 0.6)	0.760	-0.1 (-0.7, 0.6)	0.879
> K, effect 2	1.4 (-0.3, 3.1)	0.108	1.3 (0.1, 2.5)	0.035	1.4 (0.4, 2.5)	0.009
Effect 2 - 1	1.6 (-1.8, 5.0)	0.347	1.4 (-0.2, 3.0)	0.096	1.5 (0, 3.0)	0.049
LRT test		0.342		0.095		0.049

BMI: Body mass index; vBMD: Volumetric bone mineral density; LRT: Likelihood ratio test.