Hiroshige Itakura

Chiba University, Tiba, Chiba, Japan

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Publications (163)713.25 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The Japan EPA Lipid Intervention Study (JELIS) reported a 19% reduction of the risk for coronary artery disease after long-term use of pure eicosapentaenoic acid (EPA) in Japanese patients with hypercholesterolemia. The variation in plasma fatty acid composition influenced the risk of coronary events. The aim of this study was to examine in JELIS participants the possible correlation of changes in plasma fatty acids with those of serum lipids. The coefficient for the correlation between the absolute change in plasma fatty acid concentrations and the changes in serum lipids was calculated in 13,901 JELIS participants. Low-density lipoprotein (LDL) cholesterol exhibited a positive correlation with docosahexaenoic acid (DHA; r=0.117 in control group, r=0.155 in EPA group) and linoleic acid (r=0.139 in control group, r=0.177 in EPA group), but the correlation coefficients with EPA (r=0.097 in control group, r=-0.032 in EPA group) were less than 0.1. We distributed the patients into 9 groups according to tertiles of the change in EPA and DHA. The average absolute decrease of LDL cholesterol and L/H ratio in each group was significantly smaller (p<0.001) in the DHA-high tertile, but not in any EPA tertile. The changes in DHA, but not in EPA, showed a positive correlation with the changes in LDL-cholesterol.
    Journal of atherosclerosis and thrombosis 05/2012; 19(7):673-9. · 2.93 Impact Factor
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    ABSTRACT: The present study examined the importance of reducing non-high-density lipoprotein cholesterol (non-HDL-C) for the primary prevention of the occurrence of coronary artery disease (CAD) in the JELIS, and the effects of EPA. The patients were distributed into 4 subgroups using the lipid management goal for LDL-C recommended by the Japan Atherosclerosis Society guideline (2007) and the goal for non-HDL-C defined as 30 mg/dL higher than LDL-C: A) achieved both goals; B) achieved the LDL-C but not non-HDL-C goal; C) achieved the non-HDL-C but not LDL-C goal; and D) did not attain either goal. The incidences of CAD in the 4 subgroups were compared, and the effects of eicosapentaenoic acid (EPA) on the risk of CAD in these subgroups were examined. In the non-EPA group, the incidence of CAD in patients who did not achieve the goals for LDL-C or non-HDL-C was higher than in patients who achieved those goals. Patients in subgroups B, C, and D were at higher risk for CAD than those in subgroup A (B, HR 2.31; C, HR 1.90; D, HR 2.47). EPA reduced the risk of CAD by 38% in subgroups B, C, and D (p= 0.007). We reconfirmed non-HDL-C as a predictor of the risk for CAD and a residual risk marker of CAD after LDL-C-lowering therapy. EPA was useful to reduce the occurrence of CAD in patients who did not achieve the goals for LDL-C and/or non-HDL-C.
    Journal of atherosclerosis and thrombosis 12/2011; 19(2):194-204. · 2.93 Impact Factor
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    ABSTRACT: The long-term event monitoring (LEM) study evaluated the lipid-lowering efficacy and safety of fluvastatin in Japanese patients with hypercholesterolemia. The present sub-analysis focused on the impact of risk factors on event prevention. In the LEM study, patients (n=21,139) who started fluvastatin between 2000/4/1 and 2002/3/31 in Japan were prospectively registered and followed up for 3 years (secondary prevention cohort) or 5 years (primary prevention cohort). Of the patients registered, 19,084 were included in this sub-analysis. The secondary prevention group, demonstrated 8.27- and 2.89-fold higher incidence in cardiac events and cerebral events, respectively compared with the primary prevention group (P < 0.001). Complications of cerebrovascular disease demonstrated a 2.22- and 5.29-fold higher incidence in cardiac events and cerebral events (P < 0.01 and P < 0.001, respectively). Presence of diabetes mellitus (DM) in patients without complication significantly increased the incidence in both cardiac events (2.37) and cerebral events (2.15) as compared with non-DM patients for primary prevention (P < 0.001 and P < 0.01, respectively). For the secondary prevention, DM patients with complication of cardiac disease showed a significantly higher incidence in both cardiac events (1.59) and cerebral events (3.79) compared with non-DM patients (P < 0.05 and P < 0.01, respectively). In contrast, DM patients with complications of cerebrovascular disease showed a significantly higher incidence in cerebral events (2.58, P < 0.05), but not cardiac events compared with non-DM patients. Similarly, the presence of hypertension significantly increased the incidence in both cardiac (1.64) and cerebral events (1.81) for primary prevention (P < 0.01 and P < 0.05, respectively). For secondary prevention, hypertension in patients with complication of cardiac or cerebrovascular disease did not affect incidence in both cardiac and cerebral events. In the patients without complication, high triglycerides and low high density lipoprotein cholesterol (HDL-C), but not low density lipoprotein cholesterol (LDL-C), increased cerebral events, while only LDL-C significantly increased cardiac events. For secondary prevention, high triglycerides or low HDL-C, but not LDL-C, significantly increased the relative risk of cardiac events in the patients with complication of cardiac disease. The LEM study, a large-scale prospective study of long-term fluvastatin treatment for hypercholesterolemia in Japanese patients, demonstrated high impact of complications such as DM and hypertension as well as high triglycerides or low HDL-C on cardiac and cerebral events. After long-term statin treatment, the control of other factors rather than LDL-C alone might be important to avoid vascular events.
    Current Vascular Pharmacology 08/2011; 10(2):178-86. · 2.91 Impact Factor
  • Atherosclerosis Supplements 06/2011; 12(1):18-19. · 9.67 Impact Factor
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    ABSTRACT: Background/PurposeDiagnosis and management of the metabolic syndrome (MetS) are beneficial for successful aging. In spite of several criteria for MetS, there is little information on cardiometabolic risk clustering in elderly Japanese. The purpose of this study was, therefore, to determine the relationship between age-associated changes in obesity and metabolic components in the Japanese.
    Hydrometallurgy 12/2010; 1(2):42-47. · 2.22 Impact Factor
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    ABSTRACT: This long-term event monitoring (LEM) study was designed to evaluate the long-term lipid-lowering efficacy and safety of fluvastatin (Lochol®, Novartis A.G.) along with the incidence of cardiac and other events, and safety of fluvastatin in Japanese patients with hypercholesterolemia. Patients (n = 21,139) who started fluvastatin between April 1, 2000 and March 31, 2002, across 2563 centers in Japan were prospectively registered and followed up for 3 years (secondary prevention cohort) or 5 years (primary prevention cohort). Of the patients registered, 19,084 were included in this analysis. Levels of low-density lipoprotein-cholesterol (LDL-C) and total cholesterol (TC) decreased significantly in the primary (-27.1% and -18.8%) and secondary (-25.3% and -18.4%) prevention cohorts. Reductions in LDL-C (-22.1 vs. -18.2%, p < 0.0001) and TC (-16.1 vs. -13.1%, p < 0.0001) levels were significantly greater among patients aged ≥ 65 than < 65 years old. Overall, 1.7% (146/8563) and 1.1% (93/8563) of patients aged ≥ 65 years old experienced confirmed cardiac and cerebral events, compared with 1.1% (112/10,517) and 0.3% (28/10,517) of patients aged < 65 years old (p = 0.0002 and < 0.0001, respectively). Incidence of cardiac and cerebral events was lowest in patients aged < 65 years old in the primary prevention cohort and highest among patients aged ≥ 65 years old in the secondary prevention cohort. Adverse events were reported in 7.9% (1501/19,084) of patients. This large-scale, prospective, uncontrolled study confirmed the lipid-lowering efficacy and safety of long-term fluvastatin treatment for hypercholesterolemia in Japanese patients aged ≥ 65 years old. The higher incidence of cardiac and cerebral events in patients aged ≥ 65 years old in the secondary prevention cohort reflects a high-risk clinical profile with multiple classic risk factors warranting multifactorial interventions.
    Journal of Cardiology 11/2010; 57(1):77-88. · 2.57 Impact Factor
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    ABSTRACT: The Japan EPA Lipid Intervention Study (JELIS) was the first prospective randomized clinical trial to demonstrate prevention of coronary events by pure eicosapentaenoic acid (EPA). The aim of this study was to examine the relationships between various plasma fatty acid concentrations and the risk of coronary events in JELIS participants. In 15,534 participants, we calculated the hazard ratio for major coronary events (sudden cardiac death, fatal or nonfatal myocardial infarction, unstable angina pectoris, and angioplasty/stenting or coronary artery bypass grafting) relative to the on-treatment average level of plasma fatty acids with the Cox proportional hazard model. As a result of EPA intervention, the plasma EPA concentration increased, but the docosahexaenoic acid (DHA) concentration did not. The other fatty acids measured decreased slightly. The higher plasma level of EPA (hazard ratio=0.83, p=0.049, in all participants and hazard ratio=0.71, p=0.018, in the EPA intervention group), but not of DHA, was inversely associated with the risk of major coronary events. The associations between other fatty acids and the risk of major coronary events were not significant. In all JELIS participants, the risk of major coronary events was significantly decreased (20%) in the group with high (150 µg/mL or more) on-treatment plasma EPA concentration compared with that in the low (less than 87 µg/mL) group. The risk of coronary artery disease is influenced by variations in plasma fatty acid composition. Among n-3 polyunsaturated fatty acids, EPA and DHA exhibited differences in the correlation with the risk of major coronary events.
    Journal of atherosclerosis and thrombosis 11/2010; 18(2):99-107. · 2.93 Impact Factor
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    ABSTRACT: The JELIS trial examined the preventive effects of eicosapentaenoic acid (EPA) on coronary artery disease (CAD) in hypercholesterolemia. Previous investigators have reported that patients with peripheral artery disease (PAD) have a poor prognosis due to the potential risk for CAD. We conducted a subanalysis to examine whether the incidence of CAD was high in patients with PAD and whether EPA prevented the occurrence of CAD. Of 18,645 the Japan EPA lipid intervention study (JELIS) patients, 223 had PAD (control group; complicated (n=77), newly diagnosed (n=29), EPA group; complicated (n=96), newly diagnosed (n=21)). We analyzed the incidence of major coronary events (MCE) in the 2 groups. Cox proportional hazard ratio adjusted for baseline risk factor levels was used to test differences between the 2 groups. The incidence of MCE in the control group was significantly higher in patients complicated with PAD and in those newly diagnosed with PAD than in patients without PAD (complicated: hazard ratio 1.97, P=0.039; newly diagnosed: hazard ratio 2.88, P=0.030). As for patients with PAD, the EPA group had a significantly lower MCE hazard ratio than the control group (hazard ratio 0.44, 95% confidence interval 0.19-0.97, P=0.041). Subanalysis of the JELIS trial demonstrated that in patients with PAD the incidence of CAD was higher than in controls, and that EPA markedly reduced the occurrence of CAD in those patients.
    Circulation Journal 07/2010; 74(7):1451-7. · 3.69 Impact Factor
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    ABSTRACT: We previously reported that obesity (defined as a body mass index (BMI) >or=25 kg/m(2)) was not an independent risk factor for coronary heart disease (CHD) in hypercholesterolemic patients without a history of CHD from the Japan Lipid Intervention Trial (J-LIT). In this study, the obese J-LIT subgroup was further analyzed to assess CHD risk. In the J-LIT study, patients received simvastatin treatment (usually at 5 mg/day) for 6 years. A total of 38,385 patients (mean age: 57.7+/-7.9, 12,111 men) without prior CHD and/or stroke were analyzed. In this cohort, 181 CHD (acute myocardial infarction or sudden cardiac death) were observed. Obesity (n=12,929) was not an independent risk factor for CHD (relative risk; 1.18, 95% confidence interval; 0.87?1.59) after adjustment for the major risk known factors, such as age, sex, hypertension, diabetes mellitus (DM), and smoking. However, blood pressure, triglycerides, and fasting plasma glucose all increased, while high-density lipoprotein-cholesterol decreased, with increased BMI. The percentage of patients having two or three risk factors (such as dyslipidemia, hypertension, and DM) also increased with increased BMI. Obesity was not an independent risk factor for CHD in hypercholesterolemic patients on statin therapy; however, it is important to control obesity, a condition in which CHD risks accumulate, in order to improve associated risk factors along with the treatment of each risk factor, thus further reducing the risk of CHD.
    Journal of atherosclerosis and thrombosis 03/2010; 17(3):270-7. · 2.93 Impact Factor
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    ABSTRACT: JELIS was a large-scale clinical trial that investigated the effects of eicosapentaenoic acid (EPA) on coronary artery disease (CAD). In this paper, the data of patients registered in JELIS were analysed to compare the incidence of CAD between patients with impaired glucose metabolism (IGM) and normoglycemic (NG) patients. The effect of EPA on the incidence of CAD in patients with IGM was also assessed. The 18,645 hypercholesterolemic patients registered in JELIS were divided into two groups. One group consisted of patients with IGM (n=4565), which included the patients who had diabetes mellitus and patients who had a fasting plasma glucose of 110mg/dL or higher, either at the time of registration or after 6 months. The other group consisted of NG patients (n=14,080). CAD incidence of the two groups over the average 4.6-year follow-up period was compared, and the effect of EPA was assessed. Compared to NG patients, IGM patients had a significantly higher CAD hazard ratio (1.71 in the non-EPA group and 1.63 in the EPA group). The treatment with EPA resulted in a 22% decrease in the CAD incidence (P=0.048) in IGM patients and an 18% decrease (P=0.062) in NG patients. It was found that the CAD risk in IGM patients is higher than in NG patients, and that highly purified EPA is very effective in decreasing the incidence of CAD among Japanese IGM patients, even though the intake of fish is high.
    Atherosclerosis 05/2009; 206(2):535-9. · 3.71 Impact Factor
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    ABSTRACT: Results from JELIS (Japan EPA Lipid Intervention Study) demonstrated the efficacy of pure eicosapentaenoic acid (EPA) in preventing coronary artery disease (CAD) in hypercholesterolemic patients under statin treatment. The present study examined in detail whether EPA is effective for the secondary prevention of CAD. Patients with established CAD and a total cholesterol level > or =250 mg/dl were observed with a mean follow-up of 4.6 years. They were randomly assigned to receive either 1,800 mg of EPA + statin (EPA group) or statin alone (control group). The incidence of major coronary events (MCE) were compared in the 2 groups. The incidence of MCE was significantly lower in the EPA group (8.7% vs 10.7%, adjusted hazard ratio =0.77, 95% confidence interval (CI) 0.63-0.96, P=0.017, number needed to treat (NNT) =49). Among 1,050 patients with prior myocardial infarction (MI), the incidence of MCE in the EPA group (15.0%) was significantly lower than that in the control group (20.1%, adjusted hazard ratio =0.73, 95%CI 0.54-0.98, P=0.033, NNT =19). EPA is effective for secondary prevention of CAD, especially in individuals with prior MI, and should be added to conventional treatment.
    Circulation Journal 05/2009; 73(7):1283-90. · 3.69 Impact Factor
  • Atherosclerosis 05/2009; 204(1):233-233. · 3.71 Impact Factor
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    ABSTRACT: A 43-year-old woman and her 47-year-old brother were studied because of corneal opacity. They showed a marked decrease in plasma high density lipoproteins (HDL) and a decrease in the ester ratio of plasma total cholesterol. Discoidal particles were found in the HDL2 fraction (d 1.063–1.125). A marked heterogeneity of low density lipoproteins was disclosed in both patients by electron microscopy. Apoprotein analysis revealed an increase in apo E and a decrease in apo A-I and A-II in both patients. These abnormalites were similar to the data reported in other cases with hereditary lecithin: cholesterol acyltransferase (LCAT) deficiency. However, several interesting dissimilarities have been disclosed as compared with the previously reported cases. Neither patient had proteinuria, and their kidney functions were within the normal limits. The ester ratios of plasma cholesterol of both patients were the highest among the cases reported thus far. Their plasma LCAT activities were 14.4 and 15% of the normal mean values determined by Glomset-Wright's common-substrate method. The enzyme activities determined by Stokke-Norum's self-substrate method were 40.2 and 29%, respectively. These results may indicate that this inherited disorder is not characterized by absence of plasma LCAT or presence of inhibitory factors in plasma, but by the presence of partially inactive LCAT in the patients' plasma.
    Journal of Internal Medicine 04/2009; 212(4):225 - 232. · 5.79 Impact Factor
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    ABSTRACT: Inhibition of renin, the first rate-limiting enzyme in the renin-angiotensin system, has long been a therapeutic goal for treatment of hypertension. Aliskiren, the first in a new class of oral direct renin inhibitors, has been shown to reduce blood pressure (BP) in several short-term studies. In this 52-week, open-label, multicenter, parallel-group study, the long-term safety, tolerability, and efficacy of aliskiren-based therapy were assessed in Japanese patients (N=345) with mild-to-moderate essential hypertension. The study had two periods: (i) an 8-week, dose-titration period and (ii) a 44-week, fixed-dose period with an optional addition of a diuretic or a calcium channel blocker (CCB). Safety was assessed by monitoring all adverse events (AEs), serious AEs (SAEs), vital signs, laboratory parameters, ECGs, and physical examinations. Efficacy was assessed by trough mean sitting BP and responder rate. Aliskiren alone or in combination with a diuretic or a CCB was well tolerated. No deaths were reported during this study. Nine SAEs were reported, and for three of these, a possible relation to the study drug could not be excluded. The overall incidence of AEs was 85.2%, and most of these were mild-to-moderate events such as nasopharyngitis. The incidence of suspected study drug-related AEs was 25.3%. A clinically meaningful reduction of 17.6/12.8 mm Hg from baseline was achieved in the mean sitting BP at the end point with aliskiren, irrespective of the dose and additional treatments. The overall responder rate was 73.3% at the end point. In conclusion, this first long-term study in Japanese patients showed the safety and efficacy of aliskiren-based therapy in mild-to-moderate essential hypertension.
    Hypertension Research 04/2009; 32(3):169-75. · 2.94 Impact Factor
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    ABSTRACT: Japan EPA Lipid Intervention Study (JELIS) was a large-scale clinical trial examining the effects of eicosapentaenoic acid (EPA) on coronary artery disease (CAD) in hypercholesterolemic patients. Herein, we focused on risk factors other than low-density lipoprotein cholesterol (LDL-C) to investigate the effects of EPA on CAD among JELIS primary prevention cases. Hypercholesterolemic patients on statin therapy but without evidence of CAD (n=14,981) were randomly assigned to an EPA group (n=7503) or a control group (n=7478). The relationships between incident CAD, the number of CAD risk factors (hypercholesterolemia; obesity; high triglyceride (TG) or low high-density lipoprotein cholesterol (HDL-C); diabetes; and hypertension) and EPA treatment were investigated. For the control and EPA groups combined, a higher number of risk factors was directly associated with an increased incidence of CAD. Incidence was lower for the EPA group than for the control group regardless of the numbers of risk factors. Compared to patients with normal serum TG and HDL-C levels, those with abnormal levels (TG >or=150 mg/dL; HDL-C <40 mg/dL) had significantly higher CAD hazard ratio (HR: 1.71; 95% CI: 1.11-2.64; P=0.014). In this higher risk group, EPA treatment suppressed the risk of CAD by 53% (HR: 0.47; 95% CI: 0.23-0.98; P=0.043). Multiple risk factors besides cholesterol are associated with markedly increased incidence of CAD. High TG with low HDL-C represents a particularly potent risk factor. EPA was effective in reducing the incidence of CAD events for patients with this dyslipidemic pattern, suggesting that EPA may be especially beneficial in patients who with abnormal TG and HDL-C levels.
    Atherosclerosis 10/2008; 200(1):135-40. · 3.71 Impact Factor
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    ABSTRACT: The JELIS trial examined the preventive effect of eicosapentaenoic acid (EPA) against coronary artery diseases. Hypercholesterolemic patients received statin only (no EPA group: n=9319) or statin with EPA (EPA group: n=9326) for around 5 years. EPA significantly suppressed the incidence of coronary events in previous analysis. Herein, we investigated the effects of EPA on the primary and secondary prevention of stroke. We conducted a subanalysis of JELIS with respect to stroke incidence in the primary and secondary prevention subgroups defined as those without and with a prior history of stroke using Cox proportional hazard ratios, adjusted for baseline risk factor levels. As for primary prevention of stroke, this occurred in 114 (1.3%) of 8862 no EPA group and in 133 (1.5%) of 8841 EPA group. No statistically significant difference in total stroke incidence (Hazard Ratio, 1.08; 95% confidence interval, 0.95 to 1.22) was observed between the no EPA and the EPA groups. In the secondary prevention subgroup, stroke occurred in 48 (10.5%) of 457 no EPA group and in 33 (6.8%) of 485 EPA group, showing a 20% relative reduction in recurrent stroke in the EPA group (Hazard Ratio, 0.80; 95% confidence interval, 0.64 to 0.997). Administration of highly purified EPA appeared to reduce the risk of recurrent stroke in a Japanese population of hypercholesterolemic patients receiving low-dose statin therapy. Further research is needed to determine whether similar benefits are found in other populations with lower levels of fish intake. The trial is registered at ClinicalTrials.gov (number NCT00231738).
    Stroke 08/2008; 39(7):2052-8. · 6.02 Impact Factor
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    ABSTRACT: Because many Japanese patients with hypercholesterolemia have received statin therapy for nearly a decade, there was a need to investigate the benefit of long-term treatment. The Japan Lipid Intervention Trial (J-LIT) Extension 10 study was planned to continue the original J-LIT study for a total of 10 years. All 51,321 patients (including 19,905 who agreed to continue the study) were analyzed. Low-dose treatment with simvastatin (mainly 5 mg/day) was continued throughout the study period and serum lipid levels were well controlled over 10 years. Incidence of adverse drug reactions during the 4-year extension period was lower than previously. Serum total cholesterol, low-density lipoprotein-cholesterol (LDL-C), and triglyceride levels showed a positive correlation with the risk of coronary events, whereas high-density lipoprotein-cholesterol showed an inverse correlation. Patients with an LDL-C level>or=140 mg/dl had a far higher risk of coronary events than those with a level<100 mg/dl. Long-term, low-dose simvastatin therapy was safe and effective in Japanese patients with hypercholesterolemia. Serum LDL-C levels should be <140 mg/dl to decrease coronary risk and a low cholesterol level should be maintained for as long as possible.
    Circulation Journal 08/2008; 72(8):1218-24. · 3.69 Impact Factor
  • Folia Pharmacologica Japonica 05/2008; 131(4):259-67.
  • Circulation Journal - CIRC J. 01/2008; 72(8):1218-1224.
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    ABSTRACT: The aim of this study is to analyze the effect of apolipoprotein E (apo E) and methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms on serum lipid and homocysteine levels in the general Japanese population. We analyzed the polymorphisms in individuals randomly selected from among participants of Serum Lipid Survey 2000. The frequency of the epsilon2, epsilon3, and epsilon4 alleles of APOE was 4.2, 85.3, and 10.5%, respectively. Individuals with the genotype epsilon4/epsilon4 had the highest total and low-density lipoprotein (LDL) cholesterol levels, while those with epsilon2/epsilon2 had the lowest. Individuals with the epsilon2/epsilon2 and epsilon2/epsilon4 genotypes had higher remnant-like particles (RLP)-cholesterol levels than those with epsilon2epsilon3, epsilon3epsilon3, and epsilon3epsilon4. There was a trend for individuals with the epsilon2/epsilon4 and epsilon2/epsilon2 genotypes to have higher triglyceride levels, although the difference was not significant. The presence of the T allele in a MTHFR polymorphism (C667T) was associated with higher homocysteine levels, which is more prominent in men than in women. Thus in our large-scale analysis we have shown that RLP-cholesterol is better associated with, APOE genotype than triglyceride and the effect of the T allele on MTHFR polymorphism (C667T) homocysteine levels is more prominent in men than in women among Japanese.
    Journal of atherosclerosis and thrombosis 09/2007; 14(4):167-71. · 2.77 Impact Factor

Publication Stats

5k Citations
713.25 Total Impact Points

Institutions

  • 2008–2010
    • Chiba University
      Tiba, Chiba, Japan
    • Toyama University
      Тояма, Toyama, Japan
  • 2001–2010
    • Ibaraki University
      Mito-shi, Ibaraki, Japan
  • 2007–2009
    • Nippon Medical School
      • • Department of Medicine
      • • Nippon Medical School Hospital
      Tokyo, Tokyo-to, Japan
    • Kobe University
      Kōbe, Hyōgo, Japan
  • 2002–2009
    • Yamaguchi University
      • Department of Clinical Neuroscience
      Yamaguti, Yamaguchi, Japan
    • Kanazawa University
      Kanazawa, Ishikawa, Japan
    • National Institute of Infectious Diseases, Tokyo
      Edo, Tōkyō, Japan
  • 1978–2009
    • The University of Tokyo
      • • Division of Internal Medicine
      • • Department of Internal Medicine
      • • Research Center for Advanced Science and Technology
      Tokyo, Tokyo-to, Japan
  • 2005–2007
    • Kyoto University
      • Department of Geriatric Medicine
      Kyoto, Kyoto-fu, Japan
    • Sapporo Medical University
      Sapporo, Hokkaidō, Japan
  • 2000–2005
    • National Defense Medical College
      • Department of Internal Medicine
      Tokorozawa, Saitama-ken, Japan
    • Teikyo University Hospital
      Edo, Tōkyō, Japan
  • 2001–2004
    • Numazu City Hospital
      Sizuoka, Shizuoka, Japan
  • 1987–2004
    • National Institute of Health and Nutrition
      Edo, Tōkyō, Japan
  • 2003
    • Osaka City University
      • Graduate School of Medicine
      Ōsaka, Ōsaka, Japan
  • 2002–2003
    • Ochanomizu University
      • Department of Nutrition and Food Science
      Tōkyō, Japan
  • 1999
    • Daiwa House Central Research Laboratory
      Edo, Tōkyō, Japan
  • 1995
    • Korea Research Institute of Bioscience and Biotechnology KRIBB
      Anzan, Gyeonggi Province, South Korea
  • 1993
    • Osaka University of Pharmaceutical Sciences
      • Faculty of Pharmaceutical Sciences
      Ōsaka, Ōsaka, Japan