Kazuomi Kario

Prof. Dr. Kazuomi Kario


Research Focus & Metrics

Academic Career Length

36Years (1991-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 March 2003 in Circulation
Verified
Journal Article
Closed access
KKKazuomi Kario
Kazuomi Kario
TPThomas G. Pickering
Thomas G. Pickering
YUYuji Umeda
Yuji Umeda
SHSatoshi Hoshide
Satoshi Hoshide
YHYoko Hoshide
Yoko Hoshide
KSKazuyuki Shimada
Kazuyuki Shimada
Background— Cardiovascular events occur most frequently in the morning hours. We prospectively studied the association between the morning blood pressure (BP) surge and stroke in elderly hypertensives. Methods and Results— We studied stroke prognosis in 519 older hypertensives in whom ambulatory BP monitoring was performed and silent cerebral infarct was assessed by brain MRI and who were followed up prospectively. The morning BP surge (MS) was calculated as follows: mean systolic BP during the 2 hours after awakening minus mean systolic BP during the 1 hour that included the lowest sleep BP. During an average duration of 41 months (range 1 to 68 months), 44 stroke events occurred. When the patients were divided into 2 groups according to MS, those in the top decile (MS group; MS ≥55 mm Hg, n=53) had a higher baseline prevalence of multiple infarcts (57% versus 33%, P =0.001) and a higher stroke incidence (19% versus 7.3%, P =0.004) during the follow-up period than the others (non-MS group; MS <55 mm Hg, n=466). After they were matched for age and 24-hour BP, the relative risk of the MS group versus the non-MS group remained significant (relative risk=2.7, P =0.04). The MS was associated with stroke events independently of 24-hour BP, nocturnal BP dipping status, and baseline prevalence of silent infarct ( P =0.008). Conclusions— In older hypertensives, a higher morning BP surge is associated with stroke risk independently of ambulatory BP, nocturnal BP falls, and silent infarct. Reduction of the MS could thus be a new therapeutic target for preventing target organ damage and subsequent cardiovascular events in hypertensive patients.

1 October 2001 in Hypertension
Verified
Journal Article
Closed access
PDF file
KKKazuomi Kario
Kazuomi Kario
TPThomas G. Pickering
Thomas G. Pickering
TMTakefumi Matsuo
Takefumi Matsuo
SHSatoshi Hoshide
Satoshi Hoshide
JSJoseph E Schwartz
Joseph E Schwartz
KSKazuyuki Shimada
Kazuyuki Shimada
It remains uncertain whether abnormal dipping patterns of nocturnal blood pressure influence the prognosis for stroke. We studied stroke events in 575 older Japanese patients with sustained hypertension determined by ambulatory blood pressure monitoring (without medication). They were subclassified by their nocturnal systolic blood pressure fall (97 extreme-dippers, with ≥20% nocturnal systolic blood pressure fall; 230 dippers, with ≥10% but <20% fall; 185 nondippers, with ≥0% but <10% fall; and 63 reverse-dippers, with <0% fall) and were followed prospectively for an average duration of 41 months. Baseline brain magnetic resonance imaging (MRI) disclosed that the percentages with multiple silent cerebral infarct were 53% in extreme-dippers, 29% in dippers, 41% in nondippers, and 49% in reverse-dippers. There was a J-shaped relationship between dipping status and stroke incidence (extreme-dippers, 12%; dippers, 6.1%; nondippers, 7.6%; and reverse-dippers, 22%), and this remained significant in a Cox regression analysis after controlling for age, gender, body mass index, 24-hour systolic blood pressure, and antihypertensive medication. Intracranial hemorrhage was more common in reverse-dippers (29% of strokes) than in other subgroups (7.7% of strokes, P =0.04). In the extreme-dipper group, 27% of strokes were ischemic strokes that occurred during sleep (versus 8.6% of strokes in the other 3 subgroups, P =0.11). In conclusion, in older Japanese hypertensive patients, extreme dipping of nocturnal blood pressure may be related to silent and clinical cerebral ischemia through hypoperfusion during sleep or an exaggerated morning rise of blood pressure, whereas reverse dipping may pose a risk for intracranial hemorrhage.

5 March 2024 in Hypertension Research
Verified
Journal Article
Open access
PDF file
KKKazuomi Kario
Kazuomi Kario
AOAyako Okura
Ayako Okura
SHSatoshi Hoshide
Satoshi Hoshide
MMMasaki Mogi
Masaki Mogi
Thirty-year % increase of adults with hypertension in the European/ Americas and South-East Asia/ Western Pacific (WHO region). Create using the data from: World Health Organization. Global report on hypertension: the race against a silent killer. Geneva, Switzerland: 2023.

1 November 2010 in Hypertension
Verified
Journal Article
Closed access
KKKazuomi Kario
Kazuomi Kario

10 November 2020 in Circulation
Verified
Journal Article
Open access
PDF file
KKKazuomi Kario
Kazuomi Kario
SHSatoshi Hoshide
Satoshi Hoshide
HMHiroyuki Mizuno
Hiroyuki Mizuno
TKTomoyuki Kabutoya
Tomoyuki Kabutoya
MNMasafumi Nishizawa
Masafumi Nishizawa
OGOn behalf of the JAMP Study Group
On behalf of the JAMP Study Group
Background: Ambulatory and home blood pressure (BP) monitoring parameters are better predictors of cardiovascular events than are office BP monitoring parameters, but there is a lack of robust data and little information on heart failure (HF) risk. The JAMP study (Japan Ambulatory Blood Pressure Monitoring Prospective) used the same ambulatory BP monitoring device, measurement schedule, and diary-based approach to data processing across all study centers and determined the association between both nocturnal hypertension and nighttime BP dipping patterns and the occurrence of cardiovascular events, including HF, in patients with hypertension. Methods: This practitioner-based, nationwide, multicenter, prospective, observational study included patients with at least 1 cardiovascular risk factor, mostly hypertension, and free of symptomatic cardiovascular disease at baseline. All patients underwent 24-hour ambulatory BP monitoring at baseline. Patients were followed annually to determine the occurrence of primary end point cardiovascular events (atherosclerotic cardiovascular disease and HF). Results: A total of 6,359 patients (68.6±11.7 years of age, 48% men) were included in the final analysis. During a mean±SD follow-up of 4.5±2.4 years, there were 306 cardiovascular events (119 stroke, 99 coronary artery disease, 88 HF). Nighttime systolic BP was significantly associated with the risk of atherosclerotic cardiovascular disease and HF (hazard ratio adjusted for demographic and clinical risk factors per 20-mm Hg increase: 1.21 [95% CI, 1.03–1.41], P =0.017; and 1.36 [95% CI, 1.08–1.71], P =0.009, respectively). Disrupted circadian BP rhythm (riser pattern, nighttime BP higher than daytime BP) was significantly associated with higher overall cardiovascular disease risk (1.48 [95% CI, 1.05–2.08]; P =0.024), and especially HF (2.45 [95% CI, 1.34–4.48]; P =0.004) compared with normal circadian rhythm. Conclusions: Nighttime BP levels and a riser pattern were independently associated with the total cardiovascular event rate, in particular for HF. These findings suggest the importance of antihypertensive strategies targeting nighttime systolic BP. Registration: URL: https://www.umin.ac.jp/ctr/ ; Unique identifier: UMIN000020377.

1 February 2010 in Current Cardiology Reviews
Verified
Journal Article
Open access
PDF file
MNMichiaki Nagai
Michiaki Nagai
SHSatoshi Hoshide
Satoshi Hoshide
KKKazuomi Kario
Kazuomi Kario
Sleep loss is a common condition in developed countries, with evidence showing that people in Western countries are sleeping on average only 6.8 hour (hr) per night, 1.5 hr less than a century ago. Although the effects of sleep deprivation on our organs have been obscure, recent epidemiological studies have revealed relationships between sleep deprivation and hypertension (HT), coronary heart disease (CHD), and diabetes mellitus (DM). This review article summarizes the literature on these relationships. Because sleep deprivation increases sympathetic nervous system activity, this increased activity serves as a common pathophysiology for HT and DM. Adequate sleep duration may be important for preventing cardiovascular diseases in modern society.