Biomedical subjects

Elisabeth M TenVergert

Publications and source records attributed to Elisabeth M TenVergert.

10 recordsLinked to original sources

PubMed2006

RAte Control Efficacy in permanent atrial fibrillation: a comparison between lenient versus strict rate control in patients with and without heart failure. Background, aims, and design of RACE II.

BACKGROUND: Recent studies demonstrated that rate control is an acceptable alternative for rhythm control in patients with persistent atrial fibrillation (AF). However, optimal heart rate during AF is still unknown. OBJECTIVE: To show that in patients with permanent AF, lenient rate control is not inferior to strict rate control in terms of cardiovascular mortality, morbidity, neurohormonal activation, New York Heart Association class for heart failure, left ventricular function, left atrial size, quality of life, and costs. METHODS: The RACE II study is a prospective multicenter trial in The Netherlands that will randomize 500 patients with permanent AF (< or = 12 months) to strict or lenient rate control. Strict rate control is defined as a mean resting heart rate < 80 beats per minute (bpm) and heart rate during minor exercise < 110 bpm. After reaching the target, a 24-hour Holter monitoring will be performed. If necessary, drug dose reduction and/or pacemaker implantation will be performed. Lenient rate control is defined as a resting heart rate < 110 bpm. Patients will be seen after 1, 2, and 3 months (for titration of rate control drugs) and yearly thereafter. We anticipate a 25% 2.5-year cardiovascular morbidity and mortality in both groups. RESULTS: Enrollment started in January 2005 in 29 centers in The Netherlands and is expected to be concluded in June 2006. Follow-up will be at least 2 years with a maximum of 3 years. CONCLUSION: This study should provide data how to treat patients with permanent AF.

Anti-Arrhythmia Agents↗

PubMed2006

Noninferiority testing in cost-minimization studies: Practical issues concerning power analysis.

OBJECTIVES: In cost-minimization studies, it is important to establish noninferiority in the clinical effect of the treatments under investigation. The relationship between the proportion of patients reaching the end point in a study, equivalence limit (delta), and power is investigated in the context of cost-minimization studies with dichotomous clinical end points. Two formulations of the null-hypothesis, absolute and relative formulations of delta, will be explored. METHODS: Sensitivity analysis was performed, in which the effect of the predicted proportions and delta on the power in a noninferiority setting was investigated. The patterns found are discussed in terms of the practical relevance within the cost-minimization framework. RESULTS: Sensitivity analyses show different patterns of results for both null-hypotheses. The differences in these results originate from the way delta is expressed. By expressing delta as absolute difference, power grows quite fast when sample proportions are smaller than expected. In the case of a proportional delta at small sample proportions, the power to establish noninferiority remains low. CONCLUSIONS: To obtain valid results from a cost-minimization study, care has to be taken to adapt the correct methodology for noninferiority testing in clinical outcomes. Defining delta in terms of absolute differences between treatments can lead to obscured results. Although conservative, the expression of delta as a proportion of the effectiveness of the treatment as usual is found to be closer to clinical practice. The inflated delta, resulting from smaller clinical effects than expected when absolute formulation is applied, thus can be avoided.

Cost Control↗

PubMed2005

Incomplete quality of life data in lung transplant research: comparing cross sectional, repeated measures ANOVA, and multi-level analysis.

BACKGROUND: In longitudinal studies on Health Related Quality of Life (HRQL) it frequently occurs that patients have one or more missing forms, which may cause bias, and reduce the sample size. Aims of the present study were to address the problem of missing data in the field of lung transplantation (LgTX) and HRQL, to compare results obtained with different methods of analysis, and to show the value of each type of statistical method used to summarize data. METHODS: Results from cross-sectional analysis, repeated measures on complete cases (ANOVA), and a multi-level analysis were compared. The scores on the dimension 'energy' of the Nottingham Health Profile (NHP) after transplantation were used to illustrate the differences between methods. RESULTS: Compared to repeated measures ANOVA, the cross-sectional and multi-level analysis included more patients, and allowed for a longer period of follow-up. In contrast to the cross sectional analyses, in the complete case analysis, and the multi-level analysis, the correlation between different time points was taken into account. Patterns over time of the three methods were comparable. In general, results from repeated measures ANOVA showed the most favorable energy scores, and results from the multi-level analysis the least favorable. Due to the separate subgroups per time point in the cross-sectional analysis, and the relatively small number of patients in the repeated measures ANOVA, inclusion of predictors was only possible in the multi-level analysis. CONCLUSION: Results obtained with the various methods of analysis differed, indicating some reduction of bias took place. Multi-level analysis is a useful approach to study changes over time in a data set where missing data, to reduce bias, make efficient use of available data, and to include predictors, in studies concerning the effects of LgTX on HRQL.

Adult↗

PubMed2005

The effect of HLA mismatches, shared cross-reactive antigen groups, and shared HLA-DR antigens on the outcome after pediatric liver transplantation.

The aim of this study was to analyze the effect of human leukocyte antigen (HLA) class I and HLA-DR mismatching, sharing cross-reactive antigen groups (CREGs), and sharing HLA-DR antigens on the outcome after pediatric liver transplantation. Outcome parameters were graft survival, acute rejection, and portal fibrosis. A distinction was made between full-size (FSLTx) and technical-variant liver transplantation (TVLTx). A total of 136 primary transplants were analyzed. The effect of HLA on the outcome parameters was analyzed by adjusted multivariate logistic and Cox regression analysis. HLA mismatches, shared CREGs, and shared HLA-DR antigens affected neither overall graft survival nor survival after FSLTx. Survival after TVLTx was superior in case of 2 mismatches at the HLA-DR locus compared to 0 or 1 mismatch (P = 0.01) and in case of no shared HLA-DR antigen compared to 1 shared HLA-DR antigen (P = 0.004). The incidence of acute rejection was not influenced by HLA. The incidence of portal fibrosis could be analyzed in 62 1-yr biopsies and was higher after TVLTx than FSLTx (P = 0.04). The incidence of portal fibrosis after TVLTx with 0 or 1 mismatch at the HLA-DR locus was 100% compared to 43% with 2 mismatches (P = 0.004). After multivariate analysis, matching for HLA-DR and matching for TVLTx were independent risk factors for portal fibrosis. In conclusion, an overall beneficial effect of HLA matching, sharing CREGs, or sharing HLA-DR antigens was not observed. A negative effect was present for HLA-DR matching and sharing HLA-DR antigens on survival after TVLTx. HLA-DR matching might be associated with portal fibrosis in these grafts.

Adolescent↗

PubMed2004

Improved quality of life after lung transplantation in individuals with cystic fibrosis.

The aim of the present study was to assess the effect of lung transplantation (LgTX) on health-related quality of life (HRQL) in a group of patients with cystic fibrosis (CF), compared to patients with other diagnoses (non-CF). HRQL was assessed before transplantation in a group of 32 CF patients and 183 non-CF patients. After LgTX, we conducted a prospective longitudinal study among 10 CF patients and 35 non-CF patients who survived at least 31 months after LgTX. Measures were the Nottingham Health Profile (NHP), the State-Trait Anxiety Inventory (STAI), the Self-Rating Depression Scale (ZUNG), the Index of Well-Being (IWB), and the Karnofsky Performance Index. Patients in the CF group were younger, spent more days on the waiting list, and were more likely to be working or going to school than patients with other indications. Before transplantation, CF patients and non-CF patients experienced restrictions on almost all HRQL measures, compared to the general population. On the NHP dimensions of mobility and energy, CF patients had significantly better scores than non-CF patients. Between 1-4 months after transplantation, scores on the NHP, ZUNG, and Karnofsky performance indices improved, and STAI and IWB scores even occurred within the reference value in both groups. Significantly better scores in the CF group compared to the non-CF group were found on the NHP dimension of mobility 4 months after transplantation, and on the dimension of sleep 7 and 13 months after transplantation. Scores remained more or less stable over time in both groups. It may be concluded that patients in both groups experience major restrictions in HRQL before transplantation. However, pretransplant non-CF patients experience more restrictions than CF patients. After LgTX, both groups of patients showed substantial improvement in HRQL, and this improvement was maintained until 31 months after LgTX.

Adolescent↗

PubMed2004

Rate control is more cost-effective than rhythm control for patients with persistent atrial fibrillation--results from the RAte Control versus Electrical cardioversion (RACE) study.

Aims To evaluate costs between a rate and rhythm control strategy in persistent atrial fibrillation. Methods and results In a prospective substudy of RACE (Rate control versus electrical cardioversion for persistent atrial fibrillation) in 428 of the total 522 patients (206 rate control and 222 rhythm control), a cost-minimisation and cost-effectiveness analysis was performed to assess cost-effectiveness of the treatment strategies. After a mean follow-up of 2.3+/-0.6 years, the primary endpoint (cardiovascular morbidity and mortality) occurred in 17.5% (36/202) of the rate control patients and in 21.2% (47/222) of the rhythm control patients. Mean costs per patient under rate control were euro 7386 and euro 8284 under rhythm control. Cost-effectiveness analysis showed that per avoided endpoint under rate control, the cost savings were euro 24944. Under rhythm control, more costs were generated due to electrical cardioversions, hospital admissions and anti-arrhythmic medication. Costs were higher in older patients, patients with underlying heart disease, those who reached a primary endpoint and women. Heart rhythm at the end of study, did not influence costs. Conclusions Rate control is more cost-effective than rhythm control for treatment of persistent atrial fibrillation. Underlying heart disease but not heart rhythm largely accounts for costs.

Aged↗

PubMed2004

The effect of bronchiolitis obliterans syndrome on health related quality of life.

Bronchiolitis obliterans syndrome (BOS) is the most important factor limiting long-term survival after lung transplantation, and has a substantial impact on patients' daily life in terms of disability and morbidity. Aim of our study was to examine the effects of BOS on health related quality of life (HRQL) in lung transplantation patients. Data on HRQL from 29 patients who developed BOS at least 18 months earlier were studied longitudinally. HRQL measures were: the Nottingham Health Profile (NHP), the State Trait Anxiety Inventory (STAI), the Self-rating Depression Scale (ZUNG), and the Index of Well Being (IWB). Furthermore questions concerning activities of daily life and dyspnea were asked. The majority of the patients were male, and the most common diagnosis was emphysema. After the onset of BOS, significantly more restrictions were reported on the dimensions energy and mobility of the NHP. These restrictions appeared to increase over time. After the onset of BOS, STAI scores remained more or less stable and close to the value of the general population. ZUNG scores were significantly higher after the onset of BOS, and patients experienced a lower level of well being than the general population. The percentage of patients that reported to be able to perform activities of daily life without effort declined dramatically after the onset of BOS. Furthermore, the percentage of patients complaining of dyspnea increased after the onset of BOS. In conclusion, our study showed that HRQL was negatively affected by the onset of BOS. However, in spite of these less favorable long-term results, even patients who develop BOS may at least temporarily benefit from a lung transplantation.

Activities of Daily Living↗

PubMed2003

High-dose chemotherapy with hematopoietic stem-cell rescue for high-risk breast cancer.

BACKGROUND: The use of high-dose adjuvant chemotherapy for high-risk primary breast cancer is controversial. We studied its efficacy in patients with 4 to 9 or 10 or more tumor-positive axillary lymph nodes. METHODS: Patients younger than 56 years of age who had undergone surgery for breast cancer and who had no distant metastases were eligible if they had at least four tumor-positive axillary lymph nodes. Patients in the conventional-dose group received fluorouracil, epirubicin, and cyclophosphamide (FEC) every three weeks for five courses, followed by radiotherapy and tamoxifen. The high-dose treatment was identical, except that high-dose chemotherapy (6 g of cyclophosphamide per square meter of body-surface area, 480 mg of thiotepa per square meter, and 1600 mg of carboplatin per square meter) with autologous peripheral-blood hematopoietic progenitor-cell transplantation replaced the fifth course of FEC. RESULTS: Of the 885 patients, 442 were assigned to the high-dose group and 443 to the conventional-dose group. After a median follow-up of 57 months, the actuarial 5-year relapse-free survival rates were 59 percent in the conventional-dose group and 65 percent in the high-dose group (hazard ratio for relapse in the high-dose group, 0.83; 95 percent confidence interval, 0.66 to 1.03; P=0.09). In the group with 10 or more positive nodes, the relapse-free survival rates were 51 percent in the conventional-dose group and 61 percent in the high-dose group (P=0.05 by the log-rank test; hazard ratio for relapse, 0.71; 95 percent confidence interval, 0.50 to 1.00). CONCLUSIONS: High-dose alkylating therapy improves relapse-free survival among patients with stage II or III breast cancer and 10 or more positive axillary lymph nodes. This benefit may be confined to patients with HER-2/neu-negative tumors.

Adult↗

PubMed2002

Graft loss after pediatric liver transplantation.

OBJECTIVE: To describe the epidemiology and causes of graft loss after pediatric liver transplantation and to identify risk factors. SUMMARY BACKGROUND DATA: Graft failure after transplantation remains an important problem. It results in patient death or retransplantation, resulting in lower survival rates. METHODS: A series of 157 transplantations in 120 children was analyzed. Graft loss was categorized as early (within 1 month) and late (after 1 month). Risk factors were identified by analyzing recipient, donor, and transplantation variables. RESULTS: Kaplan-Meier 1-month and 1-, 3-, and 5-year patient survival rates were 85%, 82%, 77%, and 71%, respectively. Graft survival rates were 71%, 64%, 59%, and 53%, respectively. Seventy-one of 157 grafts (45%) were lost: 18 (25%) by death of patients with functioning grafts and 53 (75%) by graft-related complications. Forty-five grafts (63%) were lost early after transplantation. Main causes of early loss were vascular complications, primary nonfunction, and patient death. Main cause of late graft loss was fibrosis/cirrhosis, mainly as a result of biliary complications or unknown causes. Child-Pugh score, anhepatic phase, and urgent transplantation were risk factors for early loss. Donor age, donor/recipient weight ratio, blood loss, and technical-variant liver grafts were risk factors for late loss. CONCLUSIONS: To prevent graft loss after pediatric liver transplantation, potential recipients should be referred early so they can be transplanted in an earlier phase of their disease. Technical-variant liver grafts are risk factors for graft survival. The logistics of the operation need to be optimized to minimize the length of the anhepatic phase.

Adolescent↗

PubMedDate not supplied

Long-term quality of life in patients surviving at least 55 months after lung transplantation.

The aim of this study was to examine the long-term effect of lung transplantation on Health Related Quality of Life by studying 28 patients who survived at least 55 months after lung transplantation. Measures included the Nottingham Health Profile, questions concerning lung-specific problems, the State-Trait Anxiety Inventory, the Self-rating Depression Scale, the Index of Well-Being, the Karnofsky performance index, and questions concerning activities of daily life. Furthermore, comorbid conditions were measured. Before transplantation patients reported restrictions on almost all quality of life measures. Until approximately 43 months after transplantation there were significant improvements on most dimensions of the Nottingham Health Profile and more patients could walk without dyspnea. Significant improvements occurred with regard to the levels of anxiety, depression, and well being, and the scores on the Karnofsky performance index improved. Activities of daily life could be performed without help by most patients. After approximately 43 months patients experienced more dyspnea, anxiety, depression, and a lower level of well being. The number of patients suffering from a decrease of kidney function, drug treated hyperlipidemia, insulin dependent diabetes mellitus and bronchiolitis obliterans syndrome increased. It may be concluded that patients experience a stable and better overall quality of life after transplantation. Long-term after lung transplantation patients experience a decline on several dimensions of quality of life, which may be explained by an increase of comorbid conditions and Bronchiolitis Obliterans Syndrome.

Activities of Daily Living↗