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Featured researches published by Naofumi Doi.


JAMA | 2008

Low-dose aspirin for primary prevention of atherosclerotic events in patients with type 2 diabetes: A randomized controlled trial

Hisao Ogawa; Masafumi Nakayama; Takeshi Morimoto; Shiro Uemura; Masao Kanauchi; Naofumi Doi; Hideaki Jinnouchi; Seigo Sugiyama; Yoshihiko Saito

CONTEXT Previous trials have investigated the effects of low-dose aspirin on primary prevention of cardiovascular events, but not in patients with type 2 diabetes. OBJECTIVE To examine the efficacy of low-dose aspirin for the primary prevention of atherosclerotic events in patients with type 2 diabetes. DESIGN, SETTING, AND PARTICIPANTS Multicenter, prospective, randomized, open-label, blinded, end-point trial conducted from December 2002 through April 2008 at 163 institutions throughout Japan, which enrolled 2539 patients with type 2 diabetes without a history of atherosclerotic disease and had a median follow-up of 4.37 years. INTERVENTIONS Patients were assigned to the low-dose aspirin group (81 or 100 mg per day) or the nonaspirin group. MAIN OUTCOME MEASURES Primary end points were atherosclerotic events, including fatal or nonfatal ischemic heart disease, fatal or nonfatal stroke, and peripheral arterial disease. Secondary end points included each primary end point and combinations of primary end points as well as death from any cause. RESULTS A total of 154 atherosclerotic events occurred: 68 in the aspirin group (13.6 per 1000 person-years) and 86 in the nonaspirin group (17.0 per 1000 person-years) (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.58-1.10; log-rank test, P = .16). The combined end point of fatal coronary events and fatal cerebrovascular events occurred in 1 patient (stroke) in the aspirin group and 10 patients (5 fatal myocardial infarctions and 5 fatal strokes) in the nonaspirin group (HR, 0.10; 95% CI, 0.01-0.79; P = .0037). A total of 34 patients in the aspirin group and 38 patients in the nonaspirin group died from any cause (HR, 0.90; 95% CI, 0.57-1.14; log-rank test, P = .67). The composite of hemorrhagic stroke and significant gastrointestinal bleeding was not significantly different between the aspirin and nonaspirin groups. CONCLUSION In this study of patients with type 2 diabetes, low-dose aspirin as primary prevention did not reduce the risk of cardiovascular events. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00110448.


Critical Care Medicine | 1997

Increased plasma concentrations of adrenomedullin correlate with relaxation of vascular tone in patients with septic shock

Kenji Nishio; Yasuhiro Akai; Yoshinori Murao; Naofumi Doi; Shiro Ueda; Hisayuki Tabuse; Seiji Miyamoto; Kazuhiro Dohi; Naoto Minamino; Hiroki Shoji; Kazuo Kitamura; Kenji Kangawa; Hisayuki Matsuo

OBJECTIVE To investigate plasma concentrations of adrenomedullin in patients with septic shock and the potential association of these concentrations with relaxation of vascular tone. DESIGN Prospective, case series. SETTING Department of Emergency and Critical Care Medicine, Nara Medical University. PATIENTS Twelve patients who fulfilled the clinical criteria for severe sepsis or septic shock (as defined by the Members of the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference Committee) and 13 healthy volunteers. INTERVENTIONS Arterial blood samples were obtained via a 20-gauge cannula inserted into each patients radial artery. MEASUREMENTS AND MAIN RESULTS After extraction and purification, plasma adrenomedullin was measured by radioimmunoassay. Systemic vascular resistance index, pulmonary vascular resistance, cardiac index, and stroke volume index were determined with a thermodilution catheter. The mean plasma concentration of adrenomedullin was markedly higher in patients than in controls (226.1 +/- 66.4 [SEM] vs. 5.05 +/- 0.21 fmol/mL, p < .01). Moreover, these concentrations correlated significantly with cardiac index, stroke volume index, and heart rate values, and correlated significantly with decreases in diastolic blood pressure, systemic vascular resistance index, and pulmonary vascular resistance index values. CONCLUSIONS Enhanced production of adrenomedullin in patients with septic shock may contribute to reduced vascular tone, hypotension, or both. More data are needed to clarify the role of adrenomedullin in the regulation of vascular tone in this patient population.


Diabetes Care | 2011

Low-Dose Aspirin Therapy in Patients With Type 2 Diabetes and Reduced Glomerular Filtration Rate Subanalysis from the JPAD trial

Yoshihiko Saito; Takeshi Morimoto; Hisao Ogawa; Masafumi Nakayama; Shiro Uemura; Naofumi Doi; Hideaki Jinnouchi; Masako Waki; Hirofumi Soejima; Seigo Sugiyama; Sadanori Okada; Yasuhiro Akai

OBJECTIVE Type 2 diabetes accompanied by renal damage is a strong risk factor for atherosclerotic events. The purpose of this study was to investigate the efficacy of low-dose aspirin therapy on primary prevention of atherosclerotic events in patients with type 2 diabetes and coexisting renal dysfunction. RESEARCH DESIGN AND METHODS The Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes (JPAD) trial was a prospective, randomized, open-label trial conducted throughout Japan that enrolled 2,539 type 2 diabetic patients without a history of atherosclerotic diseases. Patients were assigned to the aspirin group (81 mg/day or 100 mg/day) or the nonaspirin group and followed for a median of 4.37 years. The primary end points were atherosclerotic events of fatal and nonfatal ischemic heart disease, stroke, and peripheral arterial disease. RESULTS The analysis included 2,523 patients who had serum creatinine measured. In 1,373 patients with baseline estimated glomerular filtration rate (eGFR) 60–89 mL/min/1.73 m2, the incidence of primary end points was significantly lower in the aspirin group than in the nonaspirin group (aspirin, 30/661; nonaspirin, 55/712; hazard ratio 0.57 [95% CI 0.36–0.88]; P = 0.011). Low-dose aspirin therapy did not reduce primary end points in patients with eGFR ≥90 mL/min/1.73 m2 (aspirin, 9/248; nonaspirin, 11/270; 0.94 [0.38–2.3]) or those with eGFR <60 mL/min/1.73 m2 (aspirin, 29/342; nonaspirin, 19/290; 1.3 [0.76–2.4]). The Cox proportional hazard model demonstrated a significant interaction between mild renal dysfunction (eGFR 60–89 mL/min/1.73 m2) and aspirin (P = 0.02). CONCLUSIONS These results suggest a differential effect of low-dose aspirin therapy in diabetic patients with eGFR 60–89 mL/min/1.73 m2.


Circulation | 2017

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients With Type 2 Diabetes MellitusClinical Perspective: 10-Year Follow-Up of a Randomized Controlled Trial

Yoshihiko Saito; Sadanori Okada; Hisao Ogawa; Hirofumi Soejima; Mio Sakuma; Masafumi Nakayama; Naofumi Doi; Hideaki Jinnouchi; Masako Waki; Izuru Masuda; Takeshi Morimoto

Background: The long-term efficacy and safety of low-dose aspirin for primary prevention of cardiovascular events in patients with type 2 diabetes mellitus are still inconclusive. Methods: The JPAD trial (Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes) was a randomized, open-label, standard care–controlled trial examining whether low-dose aspirin affected cardiovascular events in 2539 Japanese patients with type 2 diabetes mellitus and without preexisting cardiovascular disease. Patients were randomly allocated to receive aspirin (81 or 100 mg daily; aspirin group) or no aspirin (no-aspirin group) in the JPAD trial. After that trial ended in 2008, we followed up with the patients until 2015, with no attempt to change the previously assigned therapy. Primary end points were cardiovascular events, including sudden death, fatal or nonfatal coronary artery disease, fatal or nonfatal stroke, and peripheral vascular disease. For the safety analysis, hemorrhagic events, consisting of gastrointestinal bleeding, hemorrhagic stroke, and bleeding from any other sites, were also analyzed. The primary analysis was conducted for cardiovascular events among patients who retained their original allocation (a per-protocol cohort). Analyses on an intention-to-treat cohort were conducted for hemorrhagic events and statistical sensitivity. Results: The median follow-up period was 10.3 years; 1621 patients (64%) were followed up throughout the study; and 2160 patients (85%) retained their original allocation. Low-dose aspirin did not reduce cardiovascular events in the per-protocol cohort (hazard ratio, 1.14; 95% confidence interval, 0.91–1.42). Multivariable Cox proportional hazard model adjusted for age, sex, glycemic control, kidney function, smoking status, hypertension, and dyslipidemia showed similar results (hazard ratio, 1.04; 95% confidence interval, 0.83–1.30), with no heterogeneity of efficacy in subgroup analyses stratified by each of these factors (all interaction P>0.05). Sensitivity analyses on the intention-to-treat cohort yielded consistent results (hazard ratio, 1.01; 95% confidence interval, 0.82–1.25). Gastrointestinal bleeding occurred in 25 patients (2%) in the aspirin group and 12 (0.9%) in the no-aspirin group (P=0.03), and the incidence of hemorrhagic stroke was not different between groups. Conclusions: Low-dose aspirin did not affect the risk for cardiovascular events but increased risk for gastrointestinal bleeding in patients with type 2 diabetes mellitus in a primary prevention setting. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00110448.


Diabetes Care | 2011

Differential Effect of Low-Dose Aspirin for Primary Prevention of Atherosclerotic Events in Diabetes Management: A subanalysis of the JPAD trial

Sadanori Okada; Takeshi Morimoto; Hisao Ogawa; Masao Kanauchi; Masafumi Nakayama; Shiro Uemura; Naofumi Doi; Hideaki Jinnouchi; Masako Waki; Hirofumi Soejima; Mio Sakuma; Yoshihiko Saito

OBJECTIVE Recent reports showed that low-dose aspirin was ineffective in the primary prevention of cardiovascular events in diabetic patients overall. We hypothesized that low-dose aspirin would be beneficial in patients receiving insulin therapy, as a high-risk group. RESEARCH DESIGN AND METHODS This study is a subanalysis of the Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes (JPAD) trial—a randomized, controlled, open-label trial. We randomly assigned 2,539 patients with type 2 diabetes and no previous cardiovascular disease to the low-dose aspirin group (81 or 100 mg daily) or to the no-aspirin group. The median follow-up period was 4.4 years. We investigated the effect of low-dose aspirin on preventing atherosclerotic events in groups receiving different diabetes management. RESULTS At baseline, 326 patients were treated with insulin, 1,750 with oral hypoglycemic agents (OHAs), and 463 with diet alone. The insulin group had the longest history of diabetes, the worst glycemic control, and the highest prevalence of diabetic microangiopathies. The diet-alone group had the opposite characteristics. The incidence of atherosclerotic events was 26.6, 14.6, and 10.4 cases per 1,000 person-years in the insulin, OHA, and diet-alone groups, respectively. In the insulin and OHA groups, low-dose aspirin did not affect atherosclerotic events (insulin: hazard ratio [HR] 1.19 [95% CI 0.60−2.40]; OHA: HR 0.84 [0.57−1.24]). In the diet-alone group, low-dose aspirin significantly reduced atherosclerotic events, despite the lowest event rates (HR 0.21 [0.05−0.64]). CONCLUSIONS Low-dose aspirin reduced atherosclerotic events predominantly in the diet-alone group and not in the insulin or OHA groups.


Journal of Cardiology | 2013

Aspirin possibly reduces cerebrovascular events in type 2 diabetic patients with higher C-reactive protein level: Subanalysis from the JPAD Trial

Hirofumi Soejima; Hisao Ogawa; Takeshi Morimoto; Masafumi Nakayama; Sadanori Okada; Mio Sakuma; Shiro Uemura; Masao Kanauchi; Naofumi Doi; Hideaki Jinnouchi; Seigo Sugiyama; Masako Waki; Yoshihiko Saito

BACKGROUND AND PURPOSE There are few data that demonstrate a significant effect of aspirin therapy for diabetic patients as primary prevention for cardiovascular events. A guideline recommends the use of aspirin as a primary prevention strategy in patients with diabetes who are at increased cardiovascular risk including those who have additional risk factors. To clarify the effect of primary prevention with aspirin therapy on diabetic patients, the relationship between C-reactive protein (CRP) and the incidence of atherosclerotic events was investigated in participants in the Japanese primary prevention of atherosclerosis with aspirin for diabetes (JPAD) trial. METHODS AND SUBJECTS We divided the JPAD participants according to the CRP level at enrollment; CRP ≥0.1mg/dl: high CRP group, CRP <0.1mg/dl: low CRP group. The high CRP group consisted of 1131 patients and the low CRP group consisted of 398 patients. ESSENTIAL RESULTS There was no significant difference in the incidence of primary atherosclerotic events between the high CRP group and the low CRP group. Of the atherosclerotic events, the incidence of cerebrovascular events, however, was significantly higher in the high CRP group than in the low CRP group. The incidence of cerebrovascular events was higher in the high CRP group than in the low CRP group in patients without aspirin therapy, although there was no significant difference in the incidence of the cerebrovascular events between the high CRP group and the low CRP group in patients undergoing aspirin therapy. PRINCIPAL CONCLUSIONS Aspirin therapy may reduce cerebrovascular events in diabetic patients with higher CRP. Aspirin therapy could be an additional strategy as primary prevention for diabetic patients with higher CRP.


Journal of Electrocardiology | 1998

Does increased QT dispersion in the acute phase of anterior myocardial infarction predict recovery of left ventricular wall motion

Talnio Nakajima; Shinichi Fujimoto; Shiro Uemura; Atsuhiko Kawamoto; Naofumi Doi; Toshio Hashimoto; Kazuhiro Dohi

QT dispersion has been recognized as an undesirable marker because of its association with arrhythmogenicity in patients with myocardial infarction, but the relation between QT interval dispersion and wall motion abnormalities has not been clarified. After the introduction of reperfusion therapy, it was recognized that T waves were inverted twice in the course of myocardial infarction. An investigation was made of the clinical significance of QT dispersion in relation to the presence of inverted T waves and left ventricular wall motion abnormalities in 34 patients (mean age, 59 years) with acute anterior myocardial infarction who underwent successful reperfusion therapy. The amplitude of the deepest inverted T waves occurring within the first 3 days (T1) and after 3 days (T2) of myocardial infarction were measured in electrocardiographic (ECG) lead V3. On the ECGs on which T1 and T2 were recorded, QT dispersion was calculated (QTd1, QTd2), and T1 and T2 were correlated with QTd1 (r = .65) and QTd2 (r = .47), respectively. The difference between the extent of asynergy in the acute phase and the chronic phase, which was evaluated by the centerline method, was correlated with T1 (r = .63) and QTd1 (r = .67). Patients with a QTd1 of 0.1 second or longer showed a greater change in the extent of asynergy (23.4 +/- 13.1% vs 4.9 +/- 9.8%, P < .01) and less asynergy in the chronic phase (19.9 +/- 15.6% vs 46.5 +/- 14.0%, P < .01) than patients with a QTd1 of less than 0.1 second. Thus, QT dispersion in the acute phase of anterior myocardial infarction indicates recovery of left ventricular wall motion. Prolongation of the local action potential duration of the myocardium that recovers from severe ischemia may be a contributor to the increased QT dispersion that results in inversion of T waves in the acute phase of myocardial infarction.


Journal of Cardiology | 2017

Indications and outcomes of excimer laser coronary atherectomy: Efficacy and safety for thrombotic lesions—The ULTRAMAN registry

Masami Nishino; Naoki Mori; Shin Takiuchi; Daisuke Shishikura; Naofumi Doi; Toru Kataoka; Takayuki Ishihara; Noriyuki Kinoshita

BACKGROUND Excimer laser coronary atherectomy (ELCA) recently became available in Japan, but ELCAs effectiveness and safety are not clear. METHODS AND RESULTS We enrolled consecutive patients who underwent ELCA and were registered in the Utility of Laser for Transcatheter Atherectomy-Multicenter Analysis around Naniwa (ULTRAMAN) registry comprising six Japanese medical centers around Naniwa in Japan with patients registered from April 2006 to June 2015. We evaluated the catheter sizes used and compared the success rate, thrombolysis in myocardial infarction (TIMI) flow, blush score, and complications between the rich-thrombus (RT) group [acute coronary syndrome (ACS) and saphenous vein graft (SVG)] and the poor-thrombus (PT) group [in-stent restenosis (ISR), chronic total occlusion (CTO), calcification, and long or bifurcation (L&B) lesions]. Of the 328 patients, 6 (1.8%) were treated for an SVG, 175 (53.4%) were treated for ACS, 18 (5.5%) for CTO, 106 (32.4%) for ISR, 8 (2.4%) for calcification, and 15 for L&B lesions (4.6%). A 1.7-mm (concentric)-diameter ELCA catheter was used most frequently (59.4%). High success rates were achieved in both the RT and PT groups, but the TIMI flow grade and blush score were significantly lower and the complications rate was significantly higher in the RT group (n=181). CONCLUSIONS In Japan, the major indications for ELCA have been ACS and ISR. ELCA can provide a safe and effective treatment even for RT lesions.


Circulation | 2016

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients with Type 2 Diabetes: 10-year Follow-up of a Randomized Controlled Trial

Yoshihiko Saito; Sadanori Okada; Hisao Ogawa; Hirofumi Soejima; Mio Sakuma; Masafumi Nakayama; Naofumi Doi; Hideaki Jinnouchi; Masako Waki; Izuru Masuda; Takeshi Morimoto

Background: The long-term efficacy and safety of low-dose aspirin for primary prevention of cardiovascular events in patients with type 2 diabetes mellitus are still inconclusive. Methods: The JPAD trial (Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes) was a randomized, open-label, standard care–controlled trial examining whether low-dose aspirin affected cardiovascular events in 2539 Japanese patients with type 2 diabetes mellitus and without preexisting cardiovascular disease. Patients were randomly allocated to receive aspirin (81 or 100 mg daily; aspirin group) or no aspirin (no-aspirin group) in the JPAD trial. After that trial ended in 2008, we followed up with the patients until 2015, with no attempt to change the previously assigned therapy. Primary end points were cardiovascular events, including sudden death, fatal or nonfatal coronary artery disease, fatal or nonfatal stroke, and peripheral vascular disease. For the safety analysis, hemorrhagic events, consisting of gastrointestinal bleeding, hemorrhagic stroke, and bleeding from any other sites, were also analyzed. The primary analysis was conducted for cardiovascular events among patients who retained their original allocation (a per-protocol cohort). Analyses on an intention-to-treat cohort were conducted for hemorrhagic events and statistical sensitivity. Results: The median follow-up period was 10.3 years; 1621 patients (64%) were followed up throughout the study; and 2160 patients (85%) retained their original allocation. Low-dose aspirin did not reduce cardiovascular events in the per-protocol cohort (hazard ratio, 1.14; 95% confidence interval, 0.91–1.42). Multivariable Cox proportional hazard model adjusted for age, sex, glycemic control, kidney function, smoking status, hypertension, and dyslipidemia showed similar results (hazard ratio, 1.04; 95% confidence interval, 0.83–1.30), with no heterogeneity of efficacy in subgroup analyses stratified by each of these factors (all interaction P>0.05). Sensitivity analyses on the intention-to-treat cohort yielded consistent results (hazard ratio, 1.01; 95% confidence interval, 0.82–1.25). Gastrointestinal bleeding occurred in 25 patients (2%) in the aspirin group and 12 (0.9%) in the no-aspirin group (P=0.03), and the incidence of hemorrhagic stroke was not different between groups. Conclusions: Low-dose aspirin did not affect the risk for cardiovascular events but increased risk for gastrointestinal bleeding in patients with type 2 diabetes mellitus in a primary prevention setting. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00110448.


Diabetes Care | 2018

Effect of Aspirin on Cancer Chemoprevention in Japanese Patients With Type 2 Diabetes: 10-Year Observational Follow-up of a Randomized Controlled Trial

Sadanori Okada; Takeshi Morimoto; Hisao Ogawa; Mio Sakuma; Chisa Matsumoto; Hirofumi Soejima; Masafumi Nakayama; Naofumi Doi; Hideaki Jinnouchi; Masako Waki; Izuru Masuda; Yoshihiko Saito

OBJECTIVE This study analyzed the efficacy of low-dose aspirin in cancer chemoprevention in patients with diabetes. RESEARCH DESIGN AND METHODS This study was a posttrial follow-up of the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD) trial. Participants in the JPAD trial (2,536 Japanese patients with type 2 diabetes and without preexisting cardiovascular disease) were randomly allocated to receive aspirin (81 or 100 mg daily) or no aspirin. After that trial ended in 2008, we followed up with the participants until 2015, with no attempt to change the previously assigned therapy. The primary end point was total cancer incidence. We investigated the effect of low-dose aspirin on cancer incidence. RESULTS During the median follow-up period of 10.7 years, a total of 318 cancers occurred. The cancer incidence was not significantly different between the aspirin and no-aspirin groups (log-rank, P = 0.4; hazard ratio [HR], 0.92; 95% CI, 0.73–1.14; P = 0.4). In subgroup analyses, aspirin did not affect cancer incidence in men, women, or participants aged ≥65 years. However, it decreased cancer incidence in participants aged <65 years (log-rank, P = 0.05; HR, 0.67; 95% CI, 0.44–0.99; P = 0.048). After adjusting for sex, hemoglobin A1c, smoking status, and administration of metformin and statins, aspirin significantly reduced cancer incidence in participants aged <65 years (adjusted HR, 0.66; 95% CI, 0.43–0.99; P = 0.04). CONCLUSIONS Low-dose aspirin did not reduce cancer incidence in Japanese patients with type 2 diabetes.

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Shiro Uemura

Nara Medical University

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Mio Sakuma

Hyogo College of Medicine

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