The Relationship between the 24 h Blood Pressure Variability and Carotid Intima-Media Thickness: A Compared Study

Table 5

Multiple linear regression analyses performed by backward regression.

Model	Independent factor	β	Lower 95% interval	Upper 95% interval	P value	𝑅^2
Model 1^a (SD)	24 h SBPV	0.024	0.009	0.038	0.002	0.159
	Constant	0.662	0.486	0.838	0.000
Model 2^b (CV)	24 h SBPV	0.028	0.010	0.045	0.003	0.141
	Constant	0.671	0.488	0.853	0.000
Model 3^c (ARV)	Daytime SBPV	0.027	0.010	0.043	0.002	0.157
	Constant	0.689	0.527	0.851	0.000
Model 4^d (Mix)	Daytime SBPV (ARV)	0.027	0.010	0.043	0.002	0.157
	Constant	0.689	0.527	0.851	0.000

aModel 1: using the SDs of blood pressure as the independent factors. ^bModel 2: using the coefficients of variation of blood pressure as the independent factors. ^cModel 3: using average real variabilities of blood pressure as the independent factors. ^dModel 4: backward regression using the significant independent factors from model 1 to model 3.