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Chikuma Hamada

Publications and source records attributed to Chikuma Hamada.

22 records · Page 2Linked to original sources

Longitudinal changes in airflow limitation and airway hyperresponsiveness in patients with stable asthma.

BACKGROUND: There are few long-term studies of the effects of treatment on the natural course of asthma. OBJECTIVE: To investigate the longitudinal changes in airflow limitation and airway hyperresponsiveness (AHR) in asthma. METHODS: We recruited 81 outpatients (never smokers) with stable asthma from the Kyoto University Hospital. They were evaluated for pulmonary function and AHR, expressed by forced expiratory volume in 1 second (FEV1) and the provocation dose that caused a 20% fall in FEV1 (PD20-FEV1), respectively, at entry and every 6 months over 3 years. We used random effects models to estimate the slopes of these changes, and then evaluated the relationship between these changes and their predictive factors. RESULTS: Using random effects models, the percentage of the predicted FEV1 (%FEV1) declined significantly but slightly at a mean rate of 0.5%/year (P = 0.002; 95% confidence interval, 0.3 to 0.8). The mean decline rate of FEV1 was 34 mL/year. However, Log(PD20-FEV1) showed significant improvement at a mean rate of 0.088 cumulative units/year (P < 0.001; 95% confidence interval, 0.053 to 0.122). Multiple regression analysis showed that the baseline values of %FEV1 and Log(PD20-FEV1) were the most significant predictive factors for their subsequent changes, respectively. CONCLUSIONS: In stable asthmatic patients treated according to international guidelines, airflow limitation progressed at a nearly normal rate over 3 years. However, AHR continued to improve despite its ceiling effects. Multiple regression analysis revealed a significant negative relationship between the initial values and the subsequent changes in airflow limitation and AHR, respectively.

Adult↗

Double-blind placebo-controlled trial of aprindine and digoxin for the prevention of symptomatic atrial fibrillation.

A multicenter, placebo-controlled, randomized, double-blind trial compared the preventive effect of aprindine and digoxin on the recurrence of atrial fibrillation (AF) with placebo, and also compare the effectiveness of these 2 drugs in the prevention of AF. Patients with symptomatic paroxysmal or persistent AF who had converted to sinus rhythm (SR) were randomly assigned aprindine (40 mg/day), digoxin (0.25 mg/day) or placebo and followed up on an outpatient basis every 2 weeks for 6 months. Of the 141 patients from 36 participating centers, 47 were given aprindine, 47 digoxin, and 47 were on placebo. After the 6-month follow-up, the Kaplan-Meier estimates of the percentage of patients remaining free of recurrent symptomatic AF on aprindine, digoxin and placebo were 33.3%, 29.2% and 21.5%, respectively. In patients remaining in SR for 15 days after from the start of follow-up, freedom from recurrence was significantly more prevalent in the aprindine group than in the placebo group (p=0.0414), but there was no significant difference between the digoxin and placebo groups. The rate of adverse events was similar in the 3 groups. In conclusion, neither aprindine nor digoxin had a significant effect on preventing relapse of symptomatic AF; however, recurrence of AF occurred later with aprindine than with placebo or digoxin.

Aged↗

Comparison of losartan with ACE inhibitors and dihydropyridine calcium channel antagonists: a pilot study of prescription-event monitoring in Japan.

INTRODUCTION: Two pilot studies for prescription-event monitoring in Japan (J-PEM) were launched in 1997 and 1998. Here we present data regarding adverse events that were reported in the second pilot J-PEM study where losartan was compared with ACE inhibitors and dihydropyridine calcium channel antagonists. STUDY DESIGN: We conducted a cohort study with a concurrent control. METHODS/PATIENT GROUP: Study subjects prescribed losartan, an ACE inhibitor or a calcium channel antagonist were identified from prescriptions in hospital or community pharmacies. Events and other information were collected from doctors and pharmacists by mailed questionnaires. Events were coded and analysed using the Medical Dictionary for Regulatory Activities (MedDRA) terminology. Crude event rates were calculated and compared between patients treated with losartan and those receiving control drugs. When the difference was statistically significant, the event was further examined in several ways, including follow-up studies and by comparison with the data of the UK PEM study on losartan. RESULTS: Pharmacists were sent 4344 questionnaires and returned 3591 (83%), while doctors were sent 3517 questionnaires and returned 1380 (39%). In the doctors' data, the adverse event rate for losartan treatment was greater than that for ACE inhibitors and/or calcium channel antagonists for the following seven events: headache, palpitations, anaemia, insomnia, feeling abnormal, increased blood pressure and asthma. Most of these are known adverse drug reactions (ADRs) of losartan except for two events: increased blood pressure and asthma. In pharmacists' data, the event rate for losartan was significantly greater than that for control drugs for the following ten events: hot flushes, abnormal hepatic function, oedema, peripheral swelling, decreased blood pressure, increased blood pressure, rhinitis, contact dermatitis, dry skin and heat rash. The first five events were known ADRs of losartan but the other five were not. When the two sets of data were combined, the rate of an additional event, increased blood creatinine phosphokinase, which is a known ADR of losartan, was significantly greater than that for the control drugs. The six events that were not documented as ADRs for losartan were not judged to be ADRs based on the results of follow-up studies and comparison with the UK PEM study on losartan. The crude rate of cough with losartan treatment was similar to that with calcium channel antagonists, but was significantly less than that with ACE inhibitors. CONCLUSION: No novel safety problems were found in this observational cohort study on losartan. The rates of some known ADRs differed significantly between patients treated with losartan and those in the control groups.

Aged↗

Projection of creutzfeldt-jakob disease frequency based on cadaveric dura transplantation in Japan.

BACKGROUND: Projections of the size of the Creutzfeldt-Jakob disease (CJD) epidemic are of great importance for future health care and understanding of the natural history of this disease. OBJECTIVE: We have estimated the incubation period and have projected the number of patients with iatrogenic CJD in Japan, using 75 patients who were transplanted with cadaveric dura mater grafts between 1979 and 1991 and developed CJD by the end of 2000. METHODS: Several plausible scenarios, combinations of incubation period distribution forms, competing risks and exposure distributions were evaluated for the projections using data from the Japanese Ministry of Health, Labor and Welfare. RESULTS: The range of median incubation periods from the time of dura mater transplantation to the onset of the disease was 10.8-34.3 years, and the range of the number of new CJD patients between 2001 and 2020 was 21-84. CONCLUSIONS: Since the potential incubation period was estimated to be considerably long, as few as 21 and as many as 84 new patients may develop CJD by 2020.

Adult↗