School-based surveillance on visit-to-visit blood pressure variability and high blood pressure in children and adolescents

Table 2 Correlation between VVV and demographic or blood pressure variables^b

Characteristics	SBP-SD		SBP-ARV		SBP-CV		DBP-SD		DBP-ARV		DBP-CV
Characteristics	R2	P	R2	P	R2	P	R2	P	R2	P	R2	P
Age, n (%)^a	0.005	< 0.0001	0.002	< 0.0001	0.000	0.198	0.000	0.805	0.001	< 0.0001	0.000	0.647
Body mass index^a,b	0.003	< 0.0001	0.003	< 0.0001	0.000	0.118	0.001	< 0.0001	0.001	< 0.0001	0.000	0.335
Median BP measurement times	0.006	< 0.0001	0.001	0.089	0.000	0.101	0.001	< 0.0001	0.000	< 0.0001	0.000	0.462
SBP at first attendance of HPPCA^b	0.002	0.069	0.005	< 0.0001	0.000	0.945	0.004	< 0.0001	0.004	< 0.0001	0.000	0.093
DBP at first attendance of HPPCA^b	0.002	< 0.0001	0.003	< 0.0001	0.000	0.667	0.010	< 0.0001	0.012	< 0.0001	0.000	0.590
Mean SBP during 2012–2017^b	0.001	< 0.0001	0.002	< 0.0001	0.000	0.150	0.005	< 0.0001	0.006	< 0.0001	0.000	0.052
Mean DBP during 2012–2017^b	0.001	0.192	0.000	0.002	0.000	0.167	0.009	< 0.0001	0.011	< 0.0001	0.000	0.774
SBP-ARV^c	0.743	< 0.0001	–	–	–	–	–	–	–	–	–	–
SBP-CV^c	0.000	0.046	0.000	0.478	–	–	–	–	–	–	–	–
DBP-SD^c	0.151	< 0.0001	0.101	< 0.0001	0.000	0.543	–	–	–	–	–	–
DBP-ARV^c	0.094	< 0.0001	0.101	< 0.0001	0.000	0.871	0.746	< 0.0001	–	–	–	–
DBP-CV^c	0.000	0.375	0.000	0.214	0.000	0.954	0.000	0.504	0.000	0.903	–	–

VVV, visit to visit blood pressure variability; SBP, systolic blood pressure; DBP, diastolic blood pressure; SD, standard deviation; ARV, actual real variability; CV, coefficient of variation
^aAge and body mass index were measured when participants took examinations in 2018
^bAbsolute BP levels and BMI values were converted into z-scores
^cBP variability parameters were calculated based on BP z-scores during 2012–2017

ISSN: 1471-2261