wileyonlinelibrary.com/journal/jch J Clin Hypertens. 2018;20:450–455.
©2018 Wiley Periodicals, Inc.
1 | INTRODUCTION
The nondipping blood pressure (BP) pattern, as assessed by ambu-
latory BP monitoring (ABPM), has been well recognized for its asso-
ciation with cardiovascular events independent of 24- hour BP levels
in the general population and untreated hypertensive population.
Although a few studies have reported an association between the
nondipping BP pattern and cardiovascular outcomes in high- risk pop-
ulations such as patients with diabetes mellitus (DM) and/or prior car-
diovascular events, these reports have generally been limited by the
small number of patients
or the use of different protocols for ABPM
based on the meta- analysis of individual patient data.
It has been established that populations with progression of sur-
rogate organ damage or prior cardiovascular disease are at high risk
for cardiovascular events and their recurrence. Therefore, in these
populations, the impact of a nondipping BP pattern on cardiovascular
events might be lower compared with that in a population without
a high risk for cardiovascular events. In other words, the prognostic
impact of a nondipping BP pattern might be more apparent in the pop-
ulation without a high risk for cardiovascular events. Thus, the causal
relationship between a nondipping BP pattern and cardiovascular
events in populations with versus those without high risk for cardio-
vascular events still needs to be clarified.
Because of our access to data from the J- HOP (Japan Morning Surge-
Home Blood Pressure) study, we are uniquely positioned to address this
gap in knowledge. The J- HOP study enrolled patients with a history of
or risk factors for cardiovascular disease and prospectively performed
follow- up for cardiovascular events. Part of this study’s population per-
formed ABPM. Patients with carotid atherosclerosis are known to have
moderate to high risk for cardiovascular events.
The present study was
designed to determine whether the nondipping BP pattern would have a
prognostic impact in hypertensive populations with and without carotid
Received: 15 September 2017
Revised: 28 November 2017
Accepted: 8 December 2017
Carotid atherosclerosis and the association between nocturnal
blood pressure dipping and cardiovascular events
Praew Kotruchin MD
| Satoshi Hoshide MD, PhD
| Kazuomi Kario MD, PhD
Division of Cardiovascular Medicine, Jichi
Medical University School of Medicine,
Division of Emergency Medicine, Faculty of
Medicine, Khon Kaen University, Khon Kaen,
Kazuomi Kario, Department of Cardiovascular
Medicine, Jichi Medical University School of
Medicine, Shimotsuke, Tochigi, Japan.
The impact of a nondipping blood pressure (BP) pattern, defined as (awake systolic BP
– sleep systolic BP)/awake systolic BP < 0.1, on cardiovascular events in populations
with different degrees of carotid atherosclerosis is uncertain. The authors hypothe-
sized that a nondipping BP pattern would show differential predictive power for car-
diovascular events, including total cardiovascular death, sudden death, nonfatal
cardiovascular events, and nonfatal stroke, between populations with and without
carotid atherosclerosis. To test this hypothesis, the authors analyzed 493 patients
(mean age 67.9 years, 47.5% men) from the J- HOP (Japan Morning Surge- Home Blood
Pressure) study for whom ambulatory BP monitoring and carotid intima- media thick-
ness data were available. Twenty- nine cardiovascular events occurred during follow-
up (1867 person- years). A nondipping BP pattern was independently associated with
cardiovascular events in the population without carotid atherosclerosis, defined as
carotid intima- media thickness < 1.1 mm after adjustment for other cardiovascular risk
factors including age, sex, diabetes mellitus, chronic kidney disease, and 24- hour sys-
tolic BP (hazard ratio, 8.15; 95% confidence interval, 1.76–37.78 [P < .01]). This asso-
ciation was not found in the population with carotid intima- media thickness ≥ 1.1 mm.
Therefore, in the hypertensive population without carotid atherosclerosis, physicians
should consider ambulatory BP monitoring to determine the nocturnal BP pattern as
an alternative approach to assessing cardiovascular events.