Table 4.

Linear regression results for HRV response at visit 2.

HRV	Model	Variables	B	p-value	adjusted R2
RMSSD	1	Age + sex + ethnicity			0.008
		Age	−0.001	0.922
		Sex	−0.130	0.015
		Ethnicity	0.009	0.765
	2	Model 1 + visit 1 RMSSD response			0.064
		Visit 1 RMSSD response	0.262	< 0.001
	3	Model 1 + visit 1 RMSSD resting level			0.003
		Visit 1 RMSSD resting level	−0.0003	0.443
	4	Model 1 + BMI at visit 1			0.005
		BMI at visit 1	−0.0001	0.943
	5	Model 1 + BMI change			0.009
		BMI change*	−0.006	0.372
	6	Model 1 + WC at visit 1			0.005
		WC at visit 1	−0.001	0.733
	7	Model 1 + WC change			0.004
		WC change†	−0.001	0.882
	8	Model 1 + Father's education level			0.006
		Father's education level	−0.002	0.712
HF	1	Age + sex + ethnicity			0.011
		Age	0.006	0.703
		Sex	−0.13	0.010
		Ethnicity	0.080	0.362
	2	Model 1 + visit 1 HF response			0.024
		Visit 1 HF response	0.16	0.002
	3	Model 1 + visit 1 HF resting level			0.005
		Visit 1 HF resting level	−0.0002	0.333
	4	Model 1 + BMI at visit 1			0.008
		BMI at visit 1*	−0.0008	0.886
	5	Model 1 + BMI change			0.012
		BMI change	−0.022	0.286
	6	Model 1 + WC at visit 1			0.009
		WC at visit 1	−0.003	0.649
	7	Model 1 + WC change			0.008
		WC change†	−0.002	0.919
	8	Model 1 + Father's education level			0.014
		Father's education level	−0.027	0.156

^*BMI change= BMI at visit 2 – BMI at visit 1

^†WC change= WC at visit 2 - WC at visit 1

Responses of RMSSD and HF to stress were indexed by the (stress-rest)/rest ratio.

BMI= body mass index; HF= high frequency power; HRV= heart rate variability; RMSSD= root mean square of successive differences of normal RR intervals; WC= waist circumference.