Nobuaki Michihata

Dr. Nobuaki Michihata

orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

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

Representative Publications

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5 April 2022 in Circulation
Verified
Journal Article
Open access
PDF file
YSYoshimasa Seike
Yoshimasa Seike
HMHitoshi Matsuda
Hitoshi Matsuda
HSHideyuki Shimizu
Hideyuki Shimizu
SIShin Ishimaru
Shin Ishimaru
Katsuyuki HoshinaKatsuyuki Hoshina
Katsuyuki Hoshina
O(on behalf of the Japanese Committee for Stentgraft Management (JACSM)*
on behalf of the Japanese Committee for Stentgraft Management (JACSM)*
Background: We reviewed the results of endovascular aneurysm repair in patients from the Japanese Committee for Stentgraft Management registry to determine the significance of persistent type II endoleak (p-T2EL) and the risk of late adverse events, including aneurysm sac enlargement. Methods: The prospectively captured medical records of 17 099 patients <75 years of age who underwent endovascular aneurysm repair for abdominal aortic aneurysm from 2006 to 2015 were reviewed. Patients were divided into 2 groups (with or without p-T2EL) and compared to examine the correlation between p-T2EL and the occurrence of aneurysm sac enlargement after endovascular aneurysm repair. Results: Of the patients, 4957 (29.0%) had p-T2EL and 12 142 (71.0%) had no p-T2EL (non-T2EL). Mean age was significantly higher ( P <0.001), and there were fewer men ( P <0.001) in the p-T2EL group. Among comorbidities, hypertension ( P =0.019) and chronic kidney disease ( P =0.040) were more prevalent and respiratory disorders were less prevalent ( P <0.001) in the p-T2EL group. From each group, 4957 patients were matched according to propensity score to adjust for differences in patient characteristics. The cumulative incidence rates of abdominal aortic aneurysm–related mortality (p-T2EL: 52 of 4957 [1.0%] versus non-T2EL: 21 of 12 142 [0.2%]), rupture (p-T2EL: 38 of 4957 [0.8%] versus non-T2EL: 13 of 12 142 [0.1%]), sac enlargement (≥5 mm; p-T2EL: 1359 of 4957 [27.4%] versus non-T2EL: 332 of 12 142 [2.7%]), and reintervention (p-T2EL: 739 of 4957 [14.9%] versus non-T2EL: 91 of 12 142 [0.7%]) were significantly higher in the p-T2EL than the nonpT2EL group ( P <0.001). Propensity score matching yielded higher estimated incremental risk, including abdominal aortic aneurysm–related mortality, rupture, sac enlargement (≥5 mm), and reintervention for p-T2EL ( P <0.001). Cox regression analysis revealed older age ( P =0.010), proximal neck diameter ( P =0.003), and chronic kidney disease ( P <0.001) as independent positive predictors and male sex as an independent negative predictor ( P =0.015) of sac enlargement. Conclusions: The Japanese Committee for Stentgraft Management registry data show a correlation between p-T2EL and late adverse events, including aneurysm sac enlargement, reintervention, rupture, and abdominal aortic aneurysm–related mortality after endovascular aneurysm repair. Besides p-T2EL, older age, female sex, chronic kidney disease, and dilated proximal neck were associated with sac enlargement.

8 June 2021 in Circulation
Verified
Journal Article
Closed access
PDF file
Hidehiro KanekoHidehiro Kaneko
Hidehiro Kaneko
YYYuichiro Yano
Yuichiro Yano
HIHidetaka Itoh
Hidetaka Itoh
KMKojiro Morita
Kojiro Morita
HKHiroyuki Kiriyama
Hiroyuki Kiriyama
IKIssei Komuro
Issei Komuro
Background: Heart failure (HF) and atrial fibrillation (AF) are growing in prevalence worldwide. Few studies have assessed to what extent stage 1 hypertension in the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) blood pressure (BP) guidelines is associated with incident HF and AF. Methods: Analyses were conducted using a nationwide health claims database collected in the JMDC Claims Database between 2005 and 2018 (n=2,196,437; mean age, 44.0±10.9 years; 584% men). No participants were taking antihypertensive medication or had a known history of cardiovascular disease. Each participant was categorized as having normal BP (systolic BP [SBP]<120 mm Hg and diastolic BP [DBP]<80 mm Hg; n=1,155,885); elevated BP (SBP 120-129 mm Hg and DBP<80 mm Hg; n=337,390); stage 1 hypertension (SBP 130-139 mm Hg or DBP 80-89 mm Hg; n=459,820); or stage 2 hypertension (SBP≥140 mm Hg or DBP≥90 mm Hg; n=243,342). Using Cox proportional hazards models, we identified associations between BP groups and HF/AF events. We also calculated the population attributable fractions (PAFs) to estimate the proportion of HF and AF events that would be preventable if participants with stage 1 and stage 2 hypertension were to have normal BP. Results: Over a mean follow-up of 1,112±854 days, 28,056 incident HF and 7,774 incident AF events occurred. After multivariable adjustment, hazard ratios for HF and AF events were 1.10 (95% Confidence interval [CI], 1.05-1.15) and 1.07 (95% CI, 0.99-1.17), respectively, for elevated BP; 1.30 (95% CI, 1.26-1.35) and 1.21 (95% CI, 1.13-1.29), respectively, for stage 1 hypertension; and 2.05 (95% CI, 1.97-2.13) and 1.52 (95% CI, 1.41-1.64), respectively, for stage 2 hypertension vs normal BP. PAFs for HF associated with stage 1 and stage 2 hypertension were 23.2% (95% CI, 20.3%-26.0%) and 51.2% (95% CI, 49.2%-53.1%), respectively. The PAFs for AF associated with stage 1 and stage 2 hypertension were 17.4% (95% CI, 11.5%-22.9%) and 34.3% (95% CI, 29.1%-39.2%), respectively. Conclusions: Both stage 1 and stage 2 hypertension were associated with a greater incidence of HF and AF in the general population. The ACC/AHA BP classification system may help identify adults at higher risk for HF and AF events.

9 July 2021 in Nutrients
Verified
Journal Article
Open access
PDF file
MSMasahiro Shiozawa
Masahiro Shiozawa
Hidehiro KanekoHidehiro Kaneko
Hidehiro Kaneko
HIHidetaka Itoh
Hidetaka Itoh
KMKojiro Morita
Kojiro Morita
AOAkira Okada
Akira Okada
IKIssei Komuro
Issei Komuro
Data on the association between body mass index (BMI) and stroke are scarce. We aimed to examine the association between BMI and incident stroke (ischemic or hemorrhagic) and to clarify the relationship between underweight, overweight, and obesity and stroke risk stratified by sex. We analyzed the JMDC Claims Database between January 2005 and April 2020 including 2,740,778 healthy individuals (Median (interquartile) age, 45 (38–53) years; 56.2% men; median (interquartile) BMI, 22.3 (20.2–24.8) kg/m2). None of the participants had a history of cardiovascular disease. Each participant was categorized as underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5–24.9 kg/m2), overweight (BMI 25.0–29.9 kg/m2), or obese (BMI ≥ 30 kg/m2). We investigated the association of BMI with incidence stroke in men and women using the Cox regression model. We used restricted cubic spline (RCS) functions to identify the association of BMI as a continuous parameter with incident stroke. The incidence (95% confidence interval) of total stroke, ischemic stroke, and hemorrhagic stroke was 32.5 (32.0–32.9), 28.1 (27.6–28.5), and 5.5 (5.3–5.7) per 10,000 person-years in men, whereas 25.7 (25.1–26.2), 22.5 (22.0–23.0), and 4.0 (3.8–4.2) per 10,000 person-years in women, respectively. Multivariable Cox regression analysis showed that overweight and obesity were associated with a higher incidence of total and ischemic stroke in both men and women. Underweight, overweight, and obesity were associated with a higher hemorrhagic stroke incidence in men, but not in women. Restricted cubic spline showed that the risk of ischemic stroke increased in a BMI dose-dependent manner in both men and women, whereas there was a U-shaped relationship between BMI and the hemorrhagic stroke risk in men. In conclusion, overweight and obesity were associated with a greater incidence of stroke and ischemic stroke in both men and women. Furthermore, underweight, overweight, and obesity were associated with a higher hemorrhagic stroke risk in men. Our results would help in the risk stratification of future stroke based on BMI.

1 January 2012 in Journal of Adolescent Health
Verified
Journal Article
Closed access
AGAndrea K. Garber
Andrea K. Garber
NMNobuaki Michihata
Nobuaki Michihata
KHKatherine Hetnal
Katherine Hetnal
MSMary-Ann Shafer
Mary-Ann Shafer
AMAnna-Barbara Moscicki
Anna-Barbara Moscicki

1 November 2013 in Journal of Adolescent Health
Verified
Journal Article
Closed access
AGAndrea K. Garber
Andrea K. Garber
KMKasuen Mauldin
Kasuen Mauldin
NMNobuaki Michihata
Nobuaki Michihata
SBSara M. Buckelew
Sara M. Buckelew
MSMary-Ann Shafer
Mary-Ann Shafer
AMAnna-Barbara Moscicki
Anna-Barbara Moscicki

17 January 2023 in Journal of the American Heart Association
Verified
Journal Article
Closed access
Hidehiro KanekoHidehiro Kaneko
Hidehiro Kaneko
YYYuichiro Yano
Yuichiro Yano
AOAkira Okada
Akira Okada
HIHidetaka Itoh
Hidetaka Itoh
YSYuta Suzuki
Yuta Suzuki
IKIssei Komuro
Issei Komuro
Background: There have been limited data examining the age‐dependent relationship of wide‐range risk factors with the incidence of each subtype of cardiovascular disease (CVD) event. We assessed age‐related associations between modifiable risk factors and the incidence of CVD. Methods and Results: We analyzed 3 027 839 participants without a CVD history enrolled in the JMDC Claims Database (mean age, 44.8±11.0 years; 57.6% men). Each participant was categorized as aged 20 to 49 years (n=2 008 559), 50 to 59 years (n=712 273), and 60 to 75 years (n=307 007). Using Cox proportional hazards models and the relative risk reduction, we identified associations between risk factors and incident CVD, consisting of myocardial infarction, angina pectoris, stroke, and heart failure (HF). We assessed whether the association of risk factors for developing CVD would be modified by age category. Over a mean follow‐up of 1133 days, 6315 myocardial infarction, 56 447 angina pectoris, 28 079 stroke, and 56 369 HF events were recorded. The incidence of myocardial infarction, angina pectoris, stroke, and HF increased with age category. Hazard ratios of obesity, hypertension, and diabetes in the multivariable Cox regression analyses for myocardial infarction, angina pectoris, stroke, and HF decreased with age category. The relative risk reduction of obesity, hypertension, and diabetes for CVD events decreased with age category. For example, the relative risk reduction of hypertension for HF decreased from 59.2% in participants aged 20 to 49 years to 38.1% in those aged 60 to 75 years. Conclusions: The contribution of modifiable risk factor to the development of CVD is greater in younger compared with older individuals. Preventive efforts for risk factor modification may be more effective in younger people.