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PubMed2001

Selection of clinical, patient-reported, and economic end points in acute exacerbation of chronic bronchitis.

BACKGROUND: Acute exacerbation of chronic bronchitis (AECB) places tremendous burden on patients, providers, employers, and health care systems. OBJECTIVE: The purpose of this paper is to (1) review the clinical, patient-reported, and economic measures used to evaluate disease burden and treatment effectiveness in AECB in clinical trials and (2) propose a guide for selecting study end points in AECB that will help capture all the relevant disease outcomes. METHODS: Two literature searches of the PubMed database were conducted to identify studies of clinical trials in bronchitis and evaluate the clinical, patient-reported, and economic end points used in these studies. RESULTS: Previous studies have focused primarily on clinician-assessed outcomes, which do not capture the full impact of AECB on patients' lives. Reporting mechanisms for most end points have been inconsistent, limiting the ability to compare information or interpret differences. Previous studies have given limited attention to patient-reported outcomes and the economic implications of AECB. Patient-reported outcomes such as speed of symptom relief and work productivity are important parameters for assessing treatment effectiveness and provide practical information for treatment evaluation. CONCLUSIONS: Additional research is needed to develop, examine, and validate patient-reported outcomes and the indirect costs of AECB. Measuring the relevant clinical, economic, and patient-reported outcomes in AECB patients using standardized methods may lead to a clearer understanding of the disease burden and the role, effectiveness, and cost-effectiveness of antibiotic treatment.

Acute Disease↗
PubMedDate not supplied

Managing attribute--value clinical trials data using the ACT/DB client-server database system.

ACT/DB is a client-server database application for storing clinical trials and outcomes data, which is currently undergoing initial pilot use. It stores most of its data in entity-attribute-value form. Such data are segregated according to data type to allow indexing by value when possible, and binary large object data are managed in the same way as other data. ACT/DB lets an investigator design a study rapidly by defining the parameters (or attributes) that are to be gathered, as well as their logical grouping for purposes of display and data entry. ACT/DB generates customizable data entry. The data can be viewed through several standard reports as well as exported as text to external analysis programs. ACT/DB is designed to encourage reuse of parameters across multiple studies and has facilities for dictionary search and maintenance. It uses a Microsoft Access client running on Windows 95 machines, which communicates with an Oracle server running on a UNIX platform. ACT/DB is being used to manage the data for seven studies in its initial deployment.

Clinical Trials as Topic↗
PubMed2002

High-dose versus conventional-dose chemotherapy as first-salvage treatment in patients with non-seminomatous germ-cell tumors: a matched-pair analysis.

BACKGROUND: The purpose of this study was to compare high-dose chemotherapy (HDCT) with conventional-dose chemotherapy (CDCT) as first-salvage treatment in patients with relapsed or refractory non-seminomatous germ-cell tumors (NSGCT). PATIENTS AND METHODS: One hundred and ninety-three patients with relapsed or refractory NSGCT, between 1981 and 1995, were identified from two large databases. In 74 of these, intensification of first-salvage treatment by HDCT was planned. Patients were matched based on primary tumor location, response to first-line treatment, duration of this response and serum levels of the tumor markers, human chorionic gonadotrophin (HCG) and alpha-fetoprotein (AFP). Multivariate analyses were performed using event-free survival and overall survival as primary endpoints. RESULTS: Full matches on all five factors were found for 38 pairs of patients; for a further 17 pairs, matches on at least four factors could be identified. Hazard ratios in favor of HDCT were obtained between 0.72 and 0.84 [confidence interval (CI) 0.59-1.01] for event-free survival and between 0.77 and 0.83 (CI 0.60-0.99) for overall survival, depending on the type of analysis. CONCLUSIONS: The current analysis suggests a benefit from HDCT, with an estimated absolute improvement in event-free survival of between 6 and 12% and in overall survival of between 9 and 11% at 2 years. This benefit is lower than expected from previous phase I/II studies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Outcome of follicular lymphoma grade 3: is anthracycline necessary as front-line therapy?

A grading system (grades 1-3) for follicular lymphoma (FL) is used in the WHO classification for lymphoid malignancies based on the absolute number of centroblasts in the neoplastic follicles. Grade 3 FL is further subdivided into 3a and 3b depending on the presence or absence of centrocytes. A total of 231 patients with FL, referred from 1970 to 2001, were identified from our prospectively maintained database. Original diagnostic materials were available for review on 215 patients and these were reclassified according to the WHO grading system. Follicular lymphoma grades 1, 2 and 3 accounted for 92, 68 and 55 patients, respectively. No significant overall survival (OS) differences were observed among FL grades 1-3 (log rank P=0.25) or between grades 3a and 3b (log rank P=0.20). No significant failure-free survival (FFS) differences were observed among FL grades 1-3 (log rank P=0.72) or between grades 3a and 3b (log rank P=0.11). First-line anthracyclines did not influence OS or FFS (log rank P=0.86, P=0.58, respectively) in patients with FL grade 3. There are long-term survivors among patients with FL grade 3 with a continuing risk of relapse. Anthracyclines did not appear to influence survival or disease relapses when given as front-line therapy in our series. The role of anthracyclines should be further evaluated in large randomised studies.

Adolescent↗
PubMed2002

Must patients with advanced cancer choose between a Phase I trial and hospice?

BACKGROUND: Phase I oncology trials offer no meaningful chance for direct medical benefit and they may prevent patients with advanced cancer from receiving palliative care in a hospice program. However, it is not known whether dual enrollment in a Phase I trial and hospice is feasible. METHODS: Five hundred thirty-four Phase I trials were identified in a national online database, of which 179 (34%) accepted patients with a life expectancy of less than 6 months. Of these, 50 were selected randomly. Their principal investigators were surveyed by fax, with follow-up telephone calls and e-mails. Ninety-two hospices were selected randomly from a national database. Surveys were conducted by telephone with intake coordinators. Principal investigators were asked whether patients enrolled in hospice could also enroll in their trials if they were eligible in all other respects. Hospice intake coordinators were asked whether a patient with advanced cancer who met hospice eligibility criteria could also enroll in a Phase I trial. RESULTS: Surveys were completed by 45 of 50 principal investigators (90%) and by 89 of 92 hospices (97%). Although both groups were in favor of dual enrollment, principal investigators (41 of 45; 91%) were more likely to support dual enrollment than hospices (60 of 89; 67%; chi-square test, P = 0.004). Most hospices that did not support dual enrollment cited reasons that were based on concerns about payment or misunderstandings about the nature of Phase I trials. CONCLUSIONS: Most hospices and Phase I principal investigators believe that eligible patients should be allowed to enroll simultaneously in hospice and Phase I trials. These results suggest that the choice between hospice and a Phase I trial is a false dilemma and that greater collaboration in this area is needed.

Attitude of Health Personnel↗
PubMed2001

Twenty-two years of phase III trials for patients with advanced non-small-cell lung cancer: sobering results.

PURPOSE: To determine the changes in clinical trials and outcomes of patients with advanced-stage non-small-cell lung cancer (NSCLC) treated on phase III randomized trials initiated in North America from 1973 to 1994. PATIENTS AND METHODS: Phase III trials for patients with advanced-stage NSCLC were identified through a search of the National Cancer Institute's Cancer Therapy Evaluation Program database from 1973 to 1994, contact with Cooperative Groups, and by literature search of MEDLINE. Patients with advanced NSCLC treated during a similar time interval were also examined in the SEER database. Trends were tested in the number of trials, in the number and sex of patients entered on the trials, and in survival over time. RESULTS: Thirty-three phase III trials were initiated between 1973 and 1994. Twenty-four trials (73%) were initiated within the first half of this period (1973 to 1983) and accounted for 5,359 (64%) of the 8,434 eligible patients. The median number of patients treated per arm of the trials rose from 77 (1973 to 1983) to 121 (1984 to 1994) (P <.001). Five trials (15%) showed a statistically significant difference in survival between treatment arms, with a median prolongation of the median survival of 2 months (range, 0.7 to 2.7 months). CONCLUSION: Analysis of past trials in North America shows that the prolongation in median survival between two arms of a randomized study was rarely in excess of 2 months. Techniques for improved use of patient resources and appropriate trial design for phase III randomized therapeutic trials with patients with advanced NSCLC need to be developed.

Adult↗
PubMed2002

Panax ginseng: a systematic review of adverse effects and drug interactions.

Panax ginseng C. A. Meyer is a perennial herb native to Korea and China and has been used as an herbal remedy in eastern Asia for thousands of years. Modern therapeutic claims refer to vitality, immune function, cancer, cardiovascular diseases, improvement of cognitive and physical performance and sexual function. A recent systematic review of randomised controlled trials found that the efficacy of ginseng root extract could not be established beyond doubt for any of these indications. In order to obtain a balanced assessment of the therapeutic value of P. ginseng it is also necessary to consider the safety profile. In view of the extremely widespread use of P. ginseng it seems important to ask whether this herbal medicine involves health risks for the consumer. This review was conducted as a systematic attempt to document and evaluate all the available safety data on P. ginseng root extracts. Systematic searches were performed in five electronic databases and the reference lists of all papers located were checked for further relevant publications. All articles containing original data on adverse events and drug interactions with P. ginseng were included. Information was also requested from 12 manufacturers of ginseng preparations, the spontaneous reporting schemes of the WHO and national drug safety bodies. No language restrictions were imposed. Data from clinical trials suggest that the incidence of adverse events with ginseng monopreparations is similar to that with placebo. The most commonly experienced adverse events are headache, sleep and gastrointestinal disorders. The possibility of more serious adverse events is indicated in isolated case reports and data from spontaneous reporting schemes; however, causality is often difficult to determine from the evidence provided. Combination products containing ginseng as one of several constituents have been associated with serious adverse events and even fatalities. Interpretation of these cases is difficult as ingredients other than P. ginseng may have caused the problems. Possible drug interactions have been reported between P. ginseng and warfarin, phenelzine and alcohol. Collectively, these data suggest that P. ginseng monopreparations are rarely associated with adverse events or drug interactions. The ones that are documented are usually mild and transient. Combined preparations are more often associated with such events but causal attribution is usually not possible.

Clinical Trials as Topic↗
PubMed1992

Efficacy and safety of sotalol in patients with complex ventricular arrhythmias.

Sotalol is a unique beta-blocker that prolongs repolarization. Its use in 626 patients with complex ventricular ectopic activity, as reported in the literature, resulted in suppression of arrhythmia in 50 to 60% of treatment attempts. Detailed analysis of data on arrhythmias in 356 patients that were entered prospectively into a database revealed a median reduction in ventricular premature beats of 76%, compared to a median suppression of repetitive ventricular ectopic activity of 91% and of episodes of nonsustained ventricular tachycardia of 97% (p = 0.002 vs reduction of ventricular premature beats). This marked antiarrhythmic potency of sotalol in repetitive ventricular arrhythmias is thought to be due to its class III activity. Drug efficacy was independent of age, sex, the presence or absence of organic heart disease and the degree of sotalol-induced prolongation of corrected QT interval. Evaluation of left ventricular function in 215 patients treated with the drug demonstrated that depression of left ventricular ejection fraction occurred far less frequently than expected with conventional beta-blockers. Even patients with severely depressed pump function tolerated sotalol surprisingly well. There is a propensity of the drug to aggravate arrhythmia, which resulted in serious proarrhythmic events in 30 (3.5%) of 853 patients. These often consisted of torsades de pointes (9 of 30 patients). Proarrhythmia occurred primarily within the first 3 days of dosing, and exhibited a dose-dependence. In conclusion, sotalol is an effective and well-tolerated antiarrhythmic drug in patients with complex ventricular ectopic activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2002

[Anticaries effectiveness of fluoride toothpaste: a meta-analysis].

OBJECTIVE: To carry out a meta-analysis on the effectiveness of fluoride toothpaste for reducing dental caries to calculate the effect size of different hypothesis. METHODS: MEDLINE and LILACS databases were studied in the period from 1980 to 1998. To evaluate the quality of the studies, methodological rigor criteria proposed by Kay & Locker (1996) were applied after the criteria were submitted to an expert committee of CNPq (National Scientific Council of Brazil) senior researchers. Of 43 papers selected, 22 met the proposed criteria. The effect size of intervention was calculated from differences among the groups and the overall effect of five groups of hypothesis. RESULTS: The high concentration of fluoride in the toothpaste is associated with a larger effect (overall effect = -0.17 CI 95% -0.22/-0.12). The largest caries reductions were observed when comparing fluoride toothpastes and no fluoride toothpastes (overall effect = -0.29 IC 95% -0.34/-0.24). The addiction of antimicrobial agents (overall effect = -0.03 IC 95% -0.07/+0.02), differences in abrasive systems (overall effect = -0.02 IC 95% -0.09/+0.04) and active components do not increase the effectiveness of fluoride toothpastes (overall effect = -0.04 IC 95% -0.10/+0.01). CONCLUSIONS: The highest caries reductions were seen in studies where there was supervised tooth brushing. This review reinforced the importance of tooth brushing with fluoride toothpastes for controlling dental caries. However it showed the emphasis put on medical approaches for disease control rather than specific educational actions. The heterogeneity of the results shows the need to consider issues such as the scenario for implementing preventive methods in the evaluation process.

Cariostatic Agents↗
PubMed2000

Evaluation of an antihypertensive therapy utilising meta-analysis of a clinical trial database.

The emphasis on evidence-based medicine and the use of safe, cost-effective therapeutic strategies demands that management decisions be based upon evidence derived from clinical studies. Whilst prospective double blind clinical trials are regarded as the gold standard, there is no doubt that meta-analysis has proved valuable in defining the benefits of antihypertensive therapy. The antihypertensive efficacy of lacidipine has been assessed in a retrospective meta-analysis of a series of clinical studies in which the drug was compared with placebo and all the major classes of antihypertensive agent. All of the studies entered into the meta-analysis were parallel group double blind trials. Efficacy was based upon the reduction in both systolic and diastolic blood pressure and the effect on heart rate at trough immediately prior to dosing during maintenance therapy. In placebo controlled trials a clear dose response relationship was apparent with blood pressure reductions that were significantly greater than that observed with placebo at doses of 2 mg lacidipine and above. In active control trials, diastolic blood pressure reductions of 10-15 mmHg were observed at the end of the monotreatment phases (> 6-8 weeks) with a final reduction of 15-20 mmHg with the efficacy of lacidipine being equivalent to that of the comparator drug. Comparable results were also achieved for the response rates to therapy which varied between 70 and 85% at the end of the monotreatment phase and 82-98 when combination with other antihypertensive agents was permitted. There was no evidence of cardio-acceleration in any of the trials where significant blood pressure reduction was detected. This retrospective analysis in a large population base confirms the documented antihypertensive efficacy of lacidipine and demonstrates the suitability of the drug as a first line antihypertensive agent.

Adrenergic beta-Antagonists↗
PubMed1996

Cancer risk factors for selecting cohorts for large-scale chemoprevention trials.

Many anticipate that application of findings in molecular genetics will help to achieve greater precision in defining high-risk populations that may benefit from chemopreventive interventions. We must recognize, however, that genetic susceptibility, environmental factors, and complex gene-environment interactions are all likely to be risk determinants for most cancers. Cohort studies of twins and cancer indicate that having "identical" genes is generally not a very accurate predictor of cancer incidence. Data from twin studies support the suggestion that environmental factors such as tobacco use significantly influence cancer risk. The complexities of the genetic contribution to disease risk are exemplified by the development of Duchenne muscular dystrophy in only one of monozygotic twin girls, hypothesized to be the result of X chromosome inactivation, with the distribution patterns of the X chromosome being skewed to the female X in the manifesting twin and to the male X in the normal twin. Evidence from transgenic and genetic-environmental studies in animals support the possibility of genetic-environmental interactions. Calorie restriction modifies tumor expression in p53 knockout mice; a high-fat, low-calcium, low-vitamin D diet increases prepolyp hyperplasia formation in Apc-mutated mice; and calorie restriction early in life influences development of obesity in the genetically obese Zucker rat (fafa). Such environmental modulation of gene expression suggests that chemoprevention has the potential to reduce risk for both environmentally and genetically determined cancers. In view of the growing research efforts in chemoprevention, the NCI has developed a Prevention Trials Decision Network (PTDN) to formalize the evaluation and approval process for large-scale chemoprevention trials. The PTDN addresses large trial prioritization and the associated issues of minority recruitment and retention; identification and validation of biomarkers as intermediate endpoints for cancer; and chemopreventive agent selection and development. A comprehensive database is being established to support the PTDN's decision-making process and will help to determine which agents investigated in preclinical and early phase clinical trials should move to large-scale testing. Cohorts for large-scale chemoprevention trials include individuals who are determined to be at high risk as a result of genetic predisposition, carcinogenic exposure, or the presence of biomarkers indicative of increased risk. Current large-scale trials in well-defined, high-risk populations include the Breast Cancer Prevention Trial (tamoxifen), the Prostate Cancer Prevention Trial (finasteride), and the N-(4-hydroxyphenyl) retinamide (4-HPR) breast cancer prevention study being conducted in Milan. Biomarker studies will provide valuable information for refining the design and facilitating the implementation of future large-scale trials. For example, potential biomarkers are being assessed at biopsy in women with ductal carcinoma in situ (DCIS). The women are then randomized to either placebo, tamoxifen, 4-HPR, or tamoxifen plus 4-HPR for 2-4 weeks, at which time surgery is performed and the biomarkers reassessed to determine biomarker modulation by the interventions. For prostate cancer, modulation of prostatic intraepithelial neoplasia (PIN) by 4-HPR and difluoromethylornithine is being investigated; similar studies are being planned for oltipraz, dehydroepiandrosterone, and vitamin E plus selenomethionine. The validation of biomarkers as surrogate endpoints for cancer incidence in high-risk cohorts will allow more agents to be evaluated in shorter studies that use fewer subjects to achieve the desired statistical power.

Animals↗
PubMed2002

Antithrombotic therapy is associated with better survival in patients with severe heart failure and left ventricular systolic dysfunction (EPICAL study).

BACKGROUND: In patients with congestive heart failure (CHF), clinical trials have demonstrated the benefit of a number of drugs on morbidity and mortality. Nevertheless so far, there is no published controlled study of long-term antithrombotic therapy in patients with CHF. The aim of this work was to identify the relationship between cardiovascular drug use, especially antithrombotic therapy, and survival of CHF patients in current clinical practice, using an observational, population-based database. METHODS: The EPICAL study (Epidémiologie de l'Insuffisance Cardiaque Avancée en Lorraine) has identified prospectively all patients with severe CHF in the community of Lorraine. Inclusion criteria were age 20-80 years in 1994, at least one hospitalisation for cardiac decompensation, NYHA III/IV HF, ventricular ejection fraction < or =30% or cardiothoracic index > or =60% and arterial hypotension or peripheral and/or pulmonary oedema. A total of 417 consecutive patients surviving at hospital discharge were included in the database. The average follow-up period was 5 years. Univariate Cox models were used to test the relationship of baseline biological and clinical factors to survival. Cardiovascular drug prescriptions were tested in a multivariate Cox model adjusted by other known predictive factors. RESULTS: Duration of disease >1 year, renal failure, serum sodium > or =138 mmol/l, old age, serious comorbidity, previous decompensation, high doses of furosemide and vasodilators use were independently associated with poor prognosis at 1 and 5 years. Oral anticoagulants, aspirin, lipid lowering drugs and beta-blockers use were associated with better survival. There was no interaction between aspirin and angiotensin converting enzyme inhibitor use on survival. CONCLUSION: Antithrombotic therapy was associated with a better long-term survival in our study population of severe CHF. These results together with other previously published circumstantial evidence urge for a prospective, controlled and randomised trial specifically designed to evaluate optimal oral anticoagulants and aspirin in patients with congestive heart failure.

Adrenergic beta-Antagonists↗
PubMed2002

Problems with indexing and citation of articles with group authorship.

CONTEXT: It is not known whether articles with group authorship (ie, with a research group name listed as the author) are difficult to identify or whether use of group authorship may lead to problems with citation. METHODS: To examine ways in which reports of controlled trials with group authorship are indexed and citations counted in bibliographic databases, we conducted a cross-sectional study in January 2000. We identified 47 controlled trials funded by the National Eye Institute and 285 associated articles. Between January and August 2000, we searched PubMed and Science Citation Index (SCI) and recorded the citation practices for these articles. Our main outcome measures were ways in which trial reports were listed in PubMed and SCI and number of citations to each report by type of authorship. RESULTS: Of the 285 published reports identified, 126 (44%) had group authorship, 109 (38%) had modified group authorship (listing individual names plus the name of the research group), and 50 (18%) had named authors only. In PubMed, no group authors were listed in the author field (per MEDLINE rules); in SCI, group-authored reports generally were incorrectly attributed (first name on investigator list [35.3%], first name on writing committee [25.5%], contact name [16.7%], anonymous [16.7%], and other [5.9%]). Using the SCI general search, we identified citations to 16.7% of group-authored reports, compared with citations to 96.9% of reports with modified group authorship and 93.9% of citations to reports with named authors only. Other systematic search methods found that more than 98% of group-authored reports actually had been cited and that group-authored reports were cited more than other reports. CONCLUSIONS: Indexing systems are not optimally adapted to group authorship. We recommend that indexing services change their practices to include group authors in the author field to help correct the problem.

Abstracting and Indexing↗
PubMed2002

Electrical stimulation as an adjunct to spinal fusion: a meta-analysis of controlled clinical trials.

This study was a meta-analysis to examine whether electrical stimulation has a specific effect on spinal fusion. Little evidence exists on the efficacy of electrical stimulation for improving fusion rate of spinal fusion surgery. Using MEDLINE (1966-2000) and EMBASE (1985-1999), a search for articles was carried out using the Medical Subject Headings: (1) electric stimulation or electromagnetic fields, (2) spinal fusion, (3) controlled or clinical trial, and (4) human. Data were extracted from all the hit articles and additionally collected from appropriate journal lists. A total of five randomized controlled trials (RCT) on bones assessing healing of spinal fusion were identified and scored on methodological quality. All the identified studies reported positive findings, but the quality score of each trial showed wide flaws. Because of relatively homogenous subjects who had spine fusion and radiographic assessment from these studies, pooling of the data was able to be performed. Excluding one trial with the lowest score, the combined results of four trials, whose major endpoints were the success rate of the fusion, revealed a statistically significant effect of electrical stimulation with various techniques, but the selected trials still showed wide variation in view of stimulation modalities and treatment protocol. The pooled result of the studies in this review revealed the efficacy of electrical stimulation based on proved methodological quality. As problems on therapeutic modality and protocol remain, there is a further need for improvement in design to constitute acceptable proof and to establish treatment programs that better demonstrate electrical stimulation effects on spinal fusion.

Combined Modality Therapy↗
PubMedDate not supplied

The European acamprosate trials: conclusions for research and therapy.

In an excellent methodological approach, the European acamprosate study project showed that acamprosate increases sobriety times. In one randomized prospective study (n = 260) comparing acamprosate and placebo, with a 1-year treatment phase and 1-year follow-up phase, the authors found that acamprosate is effective only in Lesch type I and type II patients. To investigate the possible influence of diagnostic subgrouping, we applied the Lesch typology in a co-work with the main researchers of the UK study. The UK results concerning acamprosate's effects in the types do not mirror the Vienna results, but the numbers of type I and type II patients, retrospectively found as included in the UK centers, were too small for any conclusions. The distribution of the types points to the fact that too many type III and IV patients had been included to give acamprosate the chance to be effective. Following our typology and also these studies, we developed special treatment approaches. For relapse prevention studies, the cumulative abstinence duration together with the Lesch typology seems to be promising.

Acamprosate↗