Akiko Kada

National Hospital Organization Nagoya Medical Center, Nagoya, Aichi, Japan

Are you Akiko Kada?

Claim your profile

Publications (29)105.14 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background:The geographic distribution of cardiovascular (CV) health-care services has not been assessed systematically.Methods and Results:Data of the Japanese Circulation Society (JCS) annual survey were provided to the JCS working group with the permission of the JCS Scientific Committee. The status of CV practice in 2010 was then assessed in 47 prefectures retrospectively, along with national census and gross domestic product (GDP) data. The surveyed indices included resources (hospitals, beds and cardiologists), burden (number of inpatients), and outcome (CV mortality and autopsy) in each prefecture, which correlated well with respective populations or GDP. Inequality of geographic distribution was evident for pediatrics among the 47 prefectures, according to Lorenz curve, Gini coefficient or the maximum/minimum ratio for each index. According to the Gini coefficients, only the number of inpatients (medical or acute myocardial infarction) and beds for the total number of general hospitals or the hospitals surveyed in the present JCS study were lower than expected with regard to GDP.Conclusions:Geographic disparity of CV resources or burden was larger in pediatrics than in CV medicine or surgery. Improvement of equality in CV practice with regard to appropriateness and quality are the coming challenges for the JCS.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aldosterone is one of the major factors to cause organ damage during an acute phase of heart failure (HF), and many reports have demonstrated that patients with acute decompensated HF (ADHF) have high blood aldosterone concentrations, and the high aldosterone concentrations predict poor prognosis in patients with HF. These findings suggest that eplerenone, an antagonist of aldosterone receptors may provide a new concept and strategy for the treatment of ADHF, protecting the heart and other organs during chronic phases, depending on the restoration of hemodynamic abnormalities. EARLIER is an event-driven clinical trial with an estimated enrolment of 300 patients hospitalized with ADHF with reduced left ventricular ejection fraction. ADHF includes ischemic or non-ischemic HF, and patients can be enrolled within 72 h after the visit to the hospital. We randomize the patients taking standard therapies for ADHF to the eplerenone and placebo groups. Eplerenone, either 25 or 50 mg, is administered for 6 months in the eplerenone group, and the corresponding placebo is administered in the placebo group on top of the standard care. We set the primary endpoint as the incidence of the composite endpoint (cardiac death or first re-hospitalization due to cardiac disease) 6 months after the enrollment, and also check the quality of life, i.e., exercise capacity and safety features of eplerenone. EARLIER is a clinical trial of eplerenone targeting ADHF and also the first multicenter investigator-initiated phase III trial in the cardiovascular field in Japan, funded by the Japanese government.
    Cardiovascular Drugs and Therapy 01/2015; 29(2). DOI:10.1007/s10557-014-6565-2 · 2.95 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In clinical investigator initiated clinical trials, we frequently encounter the situation where it is very difficult to estimate the effect size and the clinically meaningful difference between the treatment and control groups. In this paper we explore various two-phase, three-stage adaptive designs which can be applied to this situation. The first phase determines whether the trial should proceed or not. If the decision is to proceed, then the sample size is re-estimated. The second phase consists of two stages, but the sample size is not re-estimated. We introduce hybrid and alpha-split designs, adding to two existing adaptive designs: Bauer-Köhne design and Lehmacher-Wassmer design. Main findings are: 1) the differences in the overall powers and the average sample number (ASN)s among these designs are small, except for the design which includes O’Brien-Fleming boundaries and the alpha-split design, 2) the two-phase, three-stage design suffers a relative loss of power by 15% but the ASN is less than 50%, as compared to the single stage design under the optimal condition, 3) two-phase, three-stage design compares with the three-stage group sequential design. We conclude that the design can be a candidate when there is no useful information on the effect size.
    01/2015; 35(2):69-93. DOI:10.5691/jjb.35.69
  • [Show abstract] [Hide abstract]
    ABSTRACT: Poor outcomes have been reported for stroke patients admitted outside of regular working hours. However, few studies have adjusted for case severity. In this nationwide assessment, we examined relationships between hospital admission time and disabilities at discharge while considering case severity.
    Journal of the American Heart Association 10/2014; 3(5):e001059. DOI:10.1161/JAHA.114.001059 · 2.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The effectiveness of comprehensive stroke center (CSC) capabilities on stroke mortality remains uncertain. We performed a nationwide study to examine whether CSC capabilities influenced in-hospital mortality of patients with ischemic and hemorrhagic stroke. Of the 1,369 certified training institutions in Japan, 749 hospitals responded to a questionnaire survey regarding CSC capabilities that queried the availability of personnel, diagnostic techniques, specific expertise, infrastructure, and educational components recommended for CSCs. Among the institutions that responded, data on patients hospitalized for stroke between April 1, 2010 and March 31, 2011 were obtained from the Japanese Diagnosis Procedure Combination database. In-hospital mortality was analyzed using hierarchical logistic regression analysis adjusted for age, sex, level of consciousness on admission, comorbidities, and the number of fulfilled CSC items in each component and in total. Data from 265 institutions and 53,170 emergency-hospitalized patients were analyzed. Mortality rates were 7.8% for patients with ischemic stroke, 16.8% for patients with intracerebral hemorrhage (ICH), and 28.1% for patients with subarachnoid hemorrhage (SAH). Mortality adjusted for age, sex, and level of consciousness was significantly correlated with personnel, infrastructural, educational, and total CSC scores in patients with ischemic stroke. Mortality was significantly correlated with diagnostic, educational, and total CSC scores in patients with ICH and with specific expertise, infrastructural, educational, and total CSC scores in patients with SAH. CSC capabilities were associated with reduced in-hospital mortality rates, and relevant aspects of care were found to be dependent on stroke type.
    PLoS ONE 05/2014; 9(5):e96819. DOI:10.1371/journal.pone.0096819 · 3.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Burnout is common among physicians and affects the quality of care. We aimed to determine the prevalence of burnout among Japanese physicians working in stroke care and evaluate personal and professional characteristics associated with burnout. A cross-sectional design was used to develop and distribute a survey to 11 211 physicians. Physician burnout was assessed using the Maslach Burnout Inventory General Survey. The predictors of burnout and the relationships among them were identified by multivariable logistic regression analysis. A total of 2724 (25.3%) physicians returned the surveys. After excluding those who were not working in stroke care or did not complete the survey appropriately, 2564 surveys were analyzed. Analysis of the participants' scores revealed that 41.1% were burned out. Multivariable analysis indicated that number of hours worked per week is positively associated with burnout. Hours slept per night, day-offs per week, years of experience, as well as income, are inversely associated with burnout. Short Form 36 mental health subscale was also inversely associated with burnout. The primary risk factors for burnout are heavy workload, short sleep duration, relatively little experience, and low mental quality of life. Prospective research is required to confirm these findings and develop programs for preventing burnout.
    Circulation Cardiovascular Quality and Outcomes 05/2014; 7(3). DOI:10.1161/CIRCOUTCOMES.113.000159 · 5.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aims Diabetes is a major risk factor for heart failure (HF). We examined whether baseline HbA1c level predicts HF incidence independent of other HF risk factors, including baseline cardiac structural and functional abnormalities. Methods In patients with type 2 diabetes, multivariable Cox regression models were constructed to examine the independent association between baseline HbA1c and future HF hospitalization. Results In 608 subjects (mean age, 66.5 years; men, 68%; mean HbA1c, 9.1% (76 mmol/mol)), 92 were hospitalized for HF during a median follow-up of 6 years. For a 1% (11 mmol/mol) increase in baseline HbA1c, the hazard ratio for HF was 1.23 (95% confidence interval, 1.1–1.7, p < 0.001) with adjustment for age, sex, body mass index, blood pressure and plasma B-type natriuretic peptide (BNP) level. The effect of HbA1c on HF was independent of baseline left ventricular (LV) ejection fraction, the ratio of peak early to late diastolic filling velocity, and prevalent/incident coronary heart disease (CHD), and was more evident in patients with enlarged LV, decreased systolic function, prevalent CHD, or prevalent HF. Conclusion In patients with type 2 diabetes, HbA1c significantly predicts future HF hospitalization independent of baseline BNP level or echocardiographic parameters.
    Diabetes research and clinical practice 05/2014; 104(2). DOI:10.1016/j.diabres.2014.02.009 · 2.54 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The association between comprehensive stroke care capacity and hospital volume of stroke interventions remains uncertain. We performed a nationwide survey in Japan to examine the impact of comprehensive stroke care capacity on the hospital volume of stroke interventions. A questionnaire on hospital characteristics, having tissue plasminogen activator (t-PA) protocols, and 25 items regarding personnel, diagnostic, specific expertise, infrastructure, and educational components recommended for comprehensive stroke centers (CSCs) was sent to 1369 professional training institutions. We examined the effect of hospital characteristics, having a t-PA protocol, and the number of fulfilled CSC items (total CSC score) on the hospital volume of t-PA infusion, removal of intracerebral hemorrhage, and coiling and clipping of intracranial aneurysms performed in 2009. Approximately 55% of hospitals responded to the survey. Facilities with t-PA protocols (85%) had a significantly higher likelihood of having 23 CSC items, for example, personnel (eg, neurosurgeons: 97.3% versus 66.1% and neurologists: 51.3% versus 27.7%), diagnostic (eg, digital cerebral angiography: 87.4% versus 43.2%), specific expertise (eg, clipping and coiling: 97.2% and 54% versus 58.9% and 14.3%, respectively), infrastructure (eg, intensive care unit: 63.9% versus 33.9%), and education (eg, professional education: 65.2% versus 20.7%). On multivariate analysis adjusted for hospital characteristics, total CSC score, but not having a t-PA protocol, was associated with the volume of all types of interventions with a clear increasing trend (P for trend < .001). We demonstrated a significant association between comprehensive stroke care capacity and the hospital volume of stroke interventions in Japan.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 10/2013; 23(5). DOI:10.1016/j.jstrokecerebrovasdis.2013.08.016 · 1.99 Impact Factor
  • Journal of Cardiac Failure 10/2013; 19(10):S162. DOI:10.1016/j.cardfail.2013.08.428 · 3.07 Impact Factor
  • Akiko Kada, Zhihong Cai, Manabu Kuroki
    [Show abstract] [Hide abstract]
    ABSTRACT: Evaluating the performance of a medical diagnostic test is an important issue in disease diagnosis. Youden [Index for rating diagnostic tests, Cancer 3 (1950), pp. 32–35] stated that the ideal measure of performance is to ensure that the control group resembles the diseased group as closely as possible in all respects except for the presence of the disease. To achieve this aim, this paper introduces the potential test result approach and proposes a new measure to evaluate the performance of medical diagnostic tests. This proposed measure, denoted as , can be interpreted as a probability that a test result T would respond to a disease status D (D∈{D 0, D 1}) for a given threshold T, and therefore evaluates both the sufficiency and necessity of the performance of a medical diagnostic test. This new measure provides a total different interpretation for the Youden index and thus helps us to better understand the essence of the Youden index and its properties. We further propose non-parametric bounds on the proposed measure based on a variety of assumptions and illustrate our results with an example from the neonatal audiology study.
    Journal of Applied Statistics 08/2013; 40(8). DOI:10.1080/02664763.2013.789832 · 0.45 Impact Factor
  • Japanese Journal of Neurosurgery 01/2013; 22(9):678-687. DOI:10.7887/jcns.22.678
  • [Show abstract] [Hide abstract]
    ABSTRACT: AIM: It has been uncertain whether patients with acute heart failure syndromes (AHFSs) benefit from a lower heart rate (HR) itself or from treatment for heart failure (HF) that reduces sympathetic tone with consequent HR reduction (HRR). The present study investigated the influence of HRR during hospitalization on the prognosis of AHFS patients. METHODS AND RESULTS: In 421 AHFS patients, we analyzed the relationship between HRR during hospitalization and the prognosis after discharge. During a mean follow-up period of 1.9years, 76 and 55 patients died or were re-hospitalized for HF, respectively. Although HR at discharge did not influence cardiac events (hazard ratio [HR]: 1.00 [95% CI; 0.99-1.02], p=0.22), the extent of HRR was a predictor of cardiac events (HR: 0.89 [0.84-0.96], p<0.001). Kaplan-Meier analysis revealed that the cardiac event rate of the HRR-positive group (≥27bpm reduction of HR from 114±24at admission to 65±11bpm at discharge) was significantly lower than that of the HRR-negative group (≤26bpm (=median value) reduction of HR from 74±14 to 71±14bpm). In the HRR-positive group, the cardiac event rate was significantly lower in patients receiving beta-blockers. Furthermore, the extent of HR change was an important predictor of cardiac events among other markers, compared with the change in systolic blood pressure or B-type natriuretic peptide. CONCLUSION: The HR itself at discharge was not associated with the prognosis, but the extent of HRR achieved by treatment of HF with beta-blockers was a strong predictor for the clinical outcome in AHFS patients.
    Journal of Cardiology 11/2012; 61(1-2). DOI:10.1016/j.jjcc.2012.08.014 · 2.57 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: No prospective studies have examined the association between blood pressure (BP) and atrial fibrillation (AFib) incidence in Asian general populations. We assessed the association between BP and incident AFib in a Japanese urban population. Methods: In total, 6,693 initially AFib-free participants (mean age 55.7 years at the baseline survey) in the Suita Study were prospectively followed for incident AFib. Participants were diagnosed with AFib if either AFib or atrial flutter was present on an electrocardiogram or if present illness or medical records indicated AFib. Health check-up examinations were conducted every 2 years. BP categories were defined by the ESH/ESC 2007 criteria. BPs were taken as the average of the second and third measurements by sphygmomanometers. Cox proportional hazard model for incident AFib were fit for BP categories and estimated hazard ratios (HRs) and 95% confidence intervals (CIs). Results: During 12.3 years of mean follow-up, 207 incident atrial fibrillation events occurred (3.73 and 1.60 per 1,000 person-years for men and women, respectively). Compared with systolic BP (SBP) <120 mmHg, diastolic BP (DBP) <80 mmHg, and optimal BP subjects, the adjusted HRs (95% CIs) for incident AFib were 1.70 (1.15-2.53) in SBP >140 mmHg, 1.36 (0.98-1.90) in DBP >90 mmHg, and 1.51 (1.02-2.24) in hypertension (SBP>140 mmHg, DBP>90 mmHg, and/or antihypertensive drug users), respectively. The adjusted HRs (95% CIs) for AFib were 1.24 (1.11-1.42) with 20 mm Hg increases in SBP and 1.10 (0.98-1.24) with 10 mm Hg increases in DBP. Conclusion: Systolic hypertensions were identified as important risk factors for incident AFib in Asia.
    Journal of Hypertension 01/2012; 30:e9-e10. DOI:10.1097/01.hjh.0000419856.44529.e3 · 4.22 Impact Factor
  • Scientific Sessions of High Blood Pressure Research; 11/2011
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Acute ischaemic stroke patients sometimes receive heparin for treatment and/or prophylaxis of thromboembolic complications. This study was designed to elucidate the incidence and clinical features of heparin-induced thrombocytopenia (HIT) in acute stroke patients treated with heparin. We conducted a prospective multicentre cohort study of 267 patients who were admitted to three stroke centres within 7 d after stroke onset. We examined clinical data until discharge and collected blood samples on days 1 and 14 of hospitalization to test anti-platelet factor 4/heparin antibodies (anti-PF4/H Abs) using an enzyme-linked immunosorbent assay (ELISA); platelet-activating antibodies were identified by serotonin-release assay (SRA). Patients with a 4Ts score ≥4 points, positive-ELISA, and positive-SRA were diagnosed as definite HIT. Heparin was administered to 172 patients (64·4%: heparin group). Anti-PF4/H Abs were detected by ELISA in 22 cases (12·8%) in the heparin group. Seven patients had 4Ts ≥ 4 points. Among them, three patients (1·7% overall) were also positive by both ELISA and SRA. National Institutes of Health Stroke Scale score on admission was high (range, 16-23) and in-hospital mortality was very high (66·7%) in definite HIT patients. In this study, the incidence of definite HIT in acute ischaemic stroke patients treated with heparin was 1·7% (95% confidence interval: 0·4-5·0). The clinical severity and outcome of definite HIT were unfavourable.
    British Journal of Haematology 06/2011; 154(3):378-86. DOI:10.1111/j.1365-2141.2011.08775.x · 4.96 Impact Factor
  • Journal of the American College of Cardiology 04/2011; 57(14). DOI:10.1016/S0735-1097(11)61035-8 · 15.34 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Nifekalant hydrochloride (NIF) is an intravenous class-III antiarrhythmic agent that purely blocks the K(+)-channel without inhibiting β-adrenergic receptors. The present study was designed to investigate the feasibility of NIF as a life-saving therapy for out-of-hospital ventricular fibrillation (VF). The Japanese Population-based Utstein-style study with basic and advanced Life Support Education study was a multi-center registry study with 4 participating institutes located at the northern urban area of Osaka, Japan. Eligible patients were those treated with NIF because of out-of-hospital VF refractory to 3 or more precordial shocks and intravenous epinephrine. Between February 2006 and February 2007, 17 patients were enrolled for the study. The time from a call for emergency medical service to the first shock was 12(6-26)min. The time from the first shock to the NIF administration was 25.5(9-264)min and the usage dose of NIF was 25(15-210)mg. When excluding 3 patients in whom percutaneous extracorporeal membrane oxygenation was applied before NIF administration, the rate of return of spontaneous circulation was 86% and the rate of admission alive to the hospital was 79%. One patient developed torsade de pointes. Intravenous administration of NIF seems to be feasible as a potential therapy for advanced cardiac life-support in patients with out-of-hospital VF, and therefore further study is warranted.
    Circulation Journal 09/2010; 74(11):2308-13. DOI:10.1253/circj.CJ-09-0759 · 3.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Fontan-type procedure has undergone 2 major modifications, including intra-atrial baffling and extracardiac conduit. To clarify the effect of these modifications on arrhythmia propensity, we analyzed chronologic changes in P-wave characteristics after atriopulmonary connection, intra-atrial baffling, or extracardiac conduit. A retrospective analysis was conducted on electrocardiographic data from 40 patients with tricuspid atresia who underwent the Fontan-type procedure and follow-up for greater than 5 years: 18 had atriopulmonary connection, 13 had intra-atrial baffling, and 9 had extracardiac conduit. The mean follow-up period in years was 19.8 for atriopulmonary connection, 13.3 for intra-atrial baffling, and 8.0 for extracardiac conduit. We analyzed chronologic changes in P-wave duration, dispersion, and amplitude and prevalence of sinus node dysfunction. Atrial tachyarrhythmia was documented in 9 patients with atriopulmonary connection but not in any patients with extracardiac conduit or intra-atrial baffling. Both P-wave maximum duration and dispersion decreased slightly over time with extracardiac conduit but increased progressively in the intra-atrial baffling and atriopulmonary connection groups. Intra-atrial baffling resulted in significantly shorter P-wave duration than atriopulmonary connection, whereas extracardiac conduit had significantly shorter P-wave duration and smaller dispersion than atriopulmonary connection and intra-atrial baffling. P-wave amplitude decreased markedly immediately after surgical intervention with intra-atrial baffling and extracardiac conduit but remained unchanged in patients undergoing atriopulmonary connection. Sinus node dysfunction was found commonly in all 3 groups. After intra-atrial baffling, patients increasingly had prolonged P-wave duration and larger dispersion associated with sinus node dysfunction, suggesting a propensity to arrhythmia, although less progressive than seen in those undergoing atriopulmonary connection. In contrast, despite an equal prevalence of sinus node dysfunction after extracardiac conduit, the lack of important changes in P-wave characteristics over time suggests that the extracardiac conduit procedure is the preferred option for optimal rhythm prognosis.
    The Journal of thoracic and cardiovascular surgery 07/2010; 140(1):137-43. DOI:10.1016/j.jtcvs.2010.03.014 · 3.99 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The long-term outcome of pediatric coronary artery bypass for patients with severe inflammatory coronary sequelae secondary to Kawasaki disease is unknown. One hundred fourteen children and adolescents ranging in age from 1 to 19 (median, 10) years at operation were followed up for as long as 25 years with a median of 19 years. The number of distal anastomoses was 1.7+/-0.8 per patient, and the internal thoracic artery was used in all but 3, most frequently for left anterior descending artery lesions. Saphenous vein grafts were used in 24 patients, mostly for non-left anterior descending artery lesions. Patients underwent multiple angiograms to evaluate their coronary and graft status. There was no operative or hospital mortality. Both 20- and 25-year survival rates were 95% (95% confidence interval [CI], 88 to 98). Five deaths occurred, all cardiac in origin. Cardiac event-free rates at 20 and 25 years were 67% and 60% (95% CI, 46 to 72), respectively. Percutaneous coronary intervention and reoperation were the most common events. Overall, the 20-year graft patency rate was 87% (95% CI, 78 to 93) for internal thoracic artery grafts (n=154) and 44% (95% CI, 26 to 61) for saphenous vein grafts (n=30) (P<0.001), and the rate for non-left anterior descending artery lesions was also significantly better for arterial grafts (87% [95% CI, 73 to 94]; n=59) than for saphenous vein grafts (42% [95% CI, 23 to 60]; n=27) (P=0.002). Eighty-eight patients (77%) remain on medications, but all 109 survivors are presently symptom free in their daily activities. Although the 25-year survival was excellent after pediatric coronary bypass for Kawasaki disease, the event-free rate declined progressively. This reality mandated continued follow-up. Reinterventions successfully managed most cardiac events. An internal thoracic artery graft was the most favorable for children.
    Circulation 06/2009; 120(1):60-8. DOI:10.1161/CIRCULATIONAHA.108.840603 · 14.95 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The prevalence of methamphetamine use and human immunodeficiency virus (HIV) incidence are high in lowland Thai society. Despite increasing social and cultural mixing among residents of highland and lowland Thai societies, however, little is known about methamphetamine use among ethnic minority villagers in the highlands. A cross-sectional survey examined Karen villagers from a developed and a less-developed village on February 24 and March 26, 2003 to evaluate the prevalence and social correlates of methamphetamine use in northern Thailand. Data were collected in face-to-face interviews using a structured questionnaire. The response rate was 79.3% (n = 548). In all, 9.9% (males 17.6%, females 1.7%) of villagers reported methamphetamine use in the previous year. Methamphetamine was used mostly by males and was significantly related to primary or lower education; to ever having worked in town; to having used opium, marijuana, or heroin in the past year; and to ever having been diagnosed with a sexually transmitted infection (STI). Since labor migration to towns is increasingly common among ethnic minorities, the prevention of methamphetamine use and of HIV/STI infection among methamphetamine users should be prioritized to prevent HIV in this minority population in Thailand.
    BMC International Health and Human Rights 06/2009; 9:11. DOI:10.1186/1472-698X-9-11 · 1.44 Impact Factor