Higher Blood Pressure Variability in White Coat Hypertension; from the Korean Ambulatory Blood Pressure Monitoring Registry.
OBJECTIVE
Blood pressure variability (BPV) was recently shown to be a risk factor of stroke. White coat hypertension (WCH) used to be regarded as innocuous, but one long-term follow-up study reported that WCH increased stroke rate compared to normotension (NT). In this study, we aimed to evaluate the relationship between WCH and BPV.


METHODS
We analyzed 1398 subjects from the Korean Ambulatory Blood Pressure Registry, who were divided into NT (n=364), masked hypertension (n=122), white coat hypertension (n=254), and sustained hypertension (n=658) groups.


RESULTS
Baseline characteristics were similar among groups. The average real variability (ARV), a highly sensitive BPV parameter, was highest in the WCH group, followed by the sustained hypertension, masked hypertension, and NT groups. The results persisted after being adjusted for covariates. The WCH vs. sustained hypertension results (adjusted mean±standard error) were as follows: 24-h systolic ARV, 22.9±0.8 vs. 19.4±0.6; 24-h diastolic ARV, 16.8±0.6 vs. 14.3±0.5; daytime systolic ARV, 21.8±0.8 vs. 16.8±0.6; and daytime diastolic ARV, 16.2±0.6 vs. 13.4±0.5 (p<0.001 for all comparisons).


CONCLUSIONS
From the registry data, we found that subjects with WCH or masked hypertension had higher BPV than NT. However, long-term follow-up data assessing the clinical influences of WCH on stroke are needed.
Department of Internal Medicine, School of Medicine, Ewha Womans University, Seoul, Korea .
In Sook
IS
Kang
Department of Internal Medicine, School of Medicine, Ewha Womans University, Seoul, Korea .
Wook Bum
WB
Pyun
Department of Internal Medicine, College of Medicine, Hanyang University, Seoul, Korea .
Jinho
J
Shin
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea .
Sang-Hyun
SH
Ihm
Department of Internal Medicine, School of Medicine, Chonnam University, Gwangju, Korea .
Ju Han
JH
Kim
Department of Internal Medicine, School of Medicine, Yonsei University, Seoul, Korea .
Sungha
S
Park
Department of Internal Medicine, School of Medicine, Seoul National University, Seongnam, Korea .
Kwang-Il
KI
Kim
Department of Internal Medicine, School of Medicine Kyung Hee University, Seoul, Korea .
Woo-Shik
WS
Kim
Department of Internal Medicine, College of Medicine, Hanyang University, Seoul, Korea .
Soon Gil
SG
Kim
Department of Internal Medicine, School of Medicine, Ewha Womans University, Seoul, Korea .
Gil Ja
GJ
Shin
Ambulatory; Blood pressure monitoring; Blood pressure variability; White coat hypertension