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PubMed2005

Prevention and treatment of postpartum hypertension.

BACKGROUND: Postpartum blood pressure (BP) is highest three to six days after birth when most women have been discharged home. A significant rise in BP may be dangerous (e.g., lead to stroke), but there is little information about how to prevent or treat postpartum hypertension. OBJECTIVES: To assess the relative benefits and risks of interventions to: (1) prevent postpartum hypertension, by assessing whether 'routine' postpartum administration of oral antihypertensive therapy is better than placebo/no treatment; and(2) treat postpartum hypertension, by assessing whether (i) oral antihypertensive therapy is better than placebo/no therapy for mild-moderate postpartum hypertension; and (ii) one antihypertensive agent offers advantages over another for mild-moderate or severe postpartum hypertension. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register (March 2004), MEDLINE (1966 to May 2003), EMBASE (1980 to January 2003), bibliographies of retrieved papers and personal files. SELECTION CRITERIA: For women with antenatal hypertension, trials comparing a medical intervention with placebo/no therapy. For women with postpartum hypertension, trials comparing one antihypertensive with either another or placebo/no therapy. DATA COLLECTION AND ANALYSIS: We extracted the data independently and were not blinded to trial characteristics or outcomes. We contacted authors for missing data when possible. MAIN RESULTS: Six trials are included. PREVENTION: Three trials (315 women; six comparisons) compared furosemide or nifedipine capsules with placebo/no therapy. There are insufficient data for conclusions about possible benefits and risks of these management strategies. Most outcomes included data from only one trial. No trial reported severe maternal hypertension or breastfeeding. TREATMENT: In two trials (106 women; three comparisons), oral timolol or hydralazine were compared with oral methyldopa for treatment of mild to moderate postpartum hypertension. In one trial (38 women; one comparison), oral hydralazine plus sublingual nifedipine were compared with sublingual nifedipine for treatment of severe postpartum hypertension. The need for additional antihypertensive therapy did not differ between groups (relative risk 4.24, 95% confidence interval 0.96 to 18.84; three trials, N = 144 women), but three antihypertensive drugs were studied. All were well tolerated. AUTHORS' CONCLUSIONS: There are no reliable data to guide management of women who are hypertensive postpartum or at increased risk of becoming so. If a clinician feels that hypertension is severe enough to treat, the agent used should be based on his/her familiarity with the drug. Future studies of prevention or treatment of postpartum hypertension should include information about use of postpartum analgesics and outcomes of severe maternal hypertension, breastfeeding, hospital length of stay, and maternal satisfaction with care.

Antihypertensive Agents↗
PubMedDate not supplied

Detecting social problems in cancer patients.

Diagnosis of and treatment for cancer may not only create physical and emotional difficulties for patients but may also have an impact on social aspects of patients' lives. Screening for social problems has not become part of routine oncology practice. This may be due to lack of a suitable questionnaire. This paper presents a psychometric analysis of the Problems Checklist with a view to assessing its usefulness as a screening tool for social problems in oncology. Evaluation was undertaken using data from an earlier study of 505 patients who completed the checklist. Frequency of endorsement, missing values, factor analysis and reliability and validity analysis of the summated scales were carried out. Missing data rates ranged from 4 to 18% over the 16 items. Fourteen items were well endorsed. Factor analysis produced a four-factor structure with components labelled daily living, relationships, economics and emotions. Reliability and validity tests endorsed the factor structure with the components on economics and emotions being particularly credible. Difficulties with relationships are harder to measure and results from the analysis suggest that this is an area that warrants further investigation. The checklist is a useful tool for highlighting problems. As a tool for screening for social problems it has some limitations.

Adaptation, Psychological↗
PubMed2005

Effectiveness of erythropoietin in the treatment of patients with malignancies: methods and preliminary results of a Cochrane review.

Cancer and cancer therapy-associated anemia may have an impact on tumor response and overall survival. Additionally, anemia represents an important economic factor. Therefore, therapeutic alternatives such as erythropoietin (EPO) and red blood cell transfusions have to be evaluated systematically. The effectiveness of recombinant human EPO to prevent or alleviate anemia in patients with malignant disease was determined. Randomized controlled trials comparing prophylaxis or treatment of anemia with EPO plus red blood cell transfusion (RBCT) or RBCT only in patients with malignant disease undergoing antineoplastic therapy were included. The endpoints needed for RBCT were hematological response (hemoglobin increase of 2g/dL or hematocrit increase of 6%), tumor response, and overall survival. Medical databases (Cochrane Library, MEDLINE, EMBASE) and conference proceedings were searched (1985-2001). Full-text and abstract publications were included as well as unpublished data. Data extraction and quality assessment were done in duplicate. All authors were contacted to obtain missing data. Out of 33 eligible studies, 27 trials with 3,287 randomized patients were included.

Anemia↗
PubMed1998

Correspondence analysis as a tool in fungal taxonomy.

The polyphasic approach to taxonomic problems has led to the creation of complex datasets that lend themselves to numerical analysis. The numerical study, however, has to deal with mathematical problems linked with the presence of mixed-type data originating from the investigations. Correspondence analysis (CA) is an ordination technique widely used in ecology and social sciences but only rarely applied to taxonomic problems. In CA corresponding variables and taxa ordination are obtained simultaneously, thus allowing to explore the taxonomic interrelationships between taxa and variables in a single analysis. CA can be used on large and small datasets, and can be applied to mixed-type data after appropriate coding. It is not sensitive to variation of class number and size and is useful to screen large unstructured datasets, to suggest which variables should be retained to discriminate samples, to detect outliers or erroneous data and to perform identification of unknown samples. It also has the advantage of handling missing data particularly well. On the other hand, CA is sensitive to outliers, which can cause a distortion of the geometric map of the points in the graphical display. Nevertheless, the sensitivity of correspondence analysis to outliers can be effectively used to verify data. Finally, based on symmetry of row and column analyses correspondence analysis can be applied to find out which characters can be used to construct identification keys and to selectively group variables by their importance for the discrimination of samples.

Cluster Analysis↗
PubMed2006

Validation of the Daily Living Tasks Dependent on Vision (DLTV) questionnaire in a U.S. population with age-related macular degeneration.

PURPOSE: The Daily Living Tasks Dependent on Vision questionnaire (DLTV) has been used to assess functional impairment among patients with age-related macular degeneration (AMD). This study evaluated the psychometric properties of the DLTV using patient-reported rates of use of services and devices in an outpatient population. METHODS: The DLTV was included in a survey mailed to members of an AMD advocacy organization. Included in the survey were questions about demographic and clinical characteristics as well as questions about use of low vision aids and care-giving. Respondents provided informed consent. Data were analyzed in SAS. RESULTS: Four respondents of 803 did not complete the DLTV; missing data were uncommon. Most (56%) respondents were male; the mean age was 73 years. Internal consistency reliability of the DLTV was 0.9699. Construct validity was demonstrated with moderate to high correlations between the DLTV and use of services and devices. The DLTV demonstrated discriminant validity and could distinguish between respondents with different levels of impairment, i.e., those who reported regular care-giving compared to those without regular care-giving. CONCLUSIONS: In this outpatient population, the DLTV demonstrated reliability and validity. This analysis complements existing research and supports the use of the DLTV in AMD patients.

Activities of Daily Living↗
PubMed1993

Analyzing individual status and change with hierarchical linear models: illustration with depression in college students.

A recently developed class of multilevel or hierarchical linear models (HLM) provides an intuitive and efficient way to estimate individual growth or change curves. The approach also models the between-subjects variation of the individual change curves with treatment factors and individual attributes. Unlike other repeated measures analysis methods common in the behavioral sciences, HLM allows the fit of data with unequal numbers of repeated observations for each subject, variable timing of observations, and missing data, features which are often characteristic of data from field studies. The application of HLM for the analysis of repeated psychological measures is discussed and illustrated here with depression data for college students. Strengths and limitations of the approach are discussed.

Adaptation, Psychological↗
PubMed1991

Descriptive study of prognostic factors influencing survival of compensated silicotic patients.

The objective of this study was to assess survival and the prognostic influencing survival of compensated silicotic patients. All workers compensated for silicosis in the Province of Quebec from 1938 to 1985 (n = 1,165) were included. Clinical data were those collected during the exam that led to a compensation decision. Due to missing data, a subcohort of 961 patients was used for multivariate analysis of clinical prognostic factors with the Cox proportional hazards model. The following factors made an independent contribution to survival: age at compensation, smoking, dyspnea, expectoration, abnormal breath sounds, radiographic appearance, and vital capacity. On the basis of the model, patients with small opacities alone on their chest radiograph and who did not have dyspnea, expectoration, or abnormal breath sounds had a survival similar to the average Quebec man; other patients had a poorer survival. We conclude that it is possible to identify at the time of compensation, silicotic patients who are likely to have a life expectancy similar to that of the general population. Symptoms and physical signs as well as radiographic and lung function abnormalities appear to be useful prognostic indicators in compensated silicotic patients.

Dyspnea↗
PubMedDate not supplied

Development of an in vitro test battery for the estimation of acute human systemic toxicity: An outline of the EDIT project. Evaluation-guided Development of New In Vitro Test Batteries.

The aim of the Evaluation-guided Development of new In Vitro Test Batteries (EDIT) multicentre programme is to establish and validate in vitro tests relevant to toxicokinetics and for organ-specific toxicity, to be incorporated into optimal test batteries for the estimation of human acute systemic toxicity. The scientific basis of EDIT is the good prediction of human acute toxicity obtained with three human cell line tests (R(2) = 0.77), in the Multicentre Evaluation of In Vitro Cytotoxicity (MEIC) programme. However, the results from the MEIC study indicated that at least two other types of in vitro test ought to be added to the existing test battery to improve the prediction of human acute systemic toxicity - to determine key kinetic events (such as biotransformation and passage through biological barriers), and to predict crucial organ-specific mechanisms not covered by the tests in the MEIC battery. The EDIT programme will be a case-by-case project, but the establishment and validation of new tests will be carried through by a common, step-wise procedure. The Scientific Committee of the EDIT programme defines the need for a specific set of toxicity or toxicokinetic data. Laboratories are then invited to perform the defined tests in order to provide the "missing" data for the EDIT reference chemicals. The results obtained will be evaluated against the MEMO (the MEIC Monograph programme) database, i.e. against human acute systemic lethal and toxicity data. The aim of the round-table discussions at the 19th Scandinavian Society for Cell Toxicology (SSCT) workshop, held in Ringsted, Denmark on 6-9 September 2001, was to identify which tests are the most important for inclusion in the MEIC battery, i.e. which types of tests the EDIT programme should focus on. It was proposed that it is important to include in vitro methods for various kinetic events, such as biotransformation, absorption in the gut, passage across the blood-brain barrier, distribution volumes, protein binding, and renal clearance/accumulation. Models for target organ toxicity were also discussed. Because several of the outlier chemicals (paracetamol, digoxin, malathion, nicotine, paraquat, atropine and potassium cyanide) in the MEIC in vivo-in vitro evaluation have a neurotoxic potential, it was proposed that the development within the EDIT target organ programme should initially be focused on the nervous system.

Biotransformation↗
PubMed2004

Integration challenges of clinical information systems developed without a shared data dictionary.

Legacy systems have proven to be long-term integration challenges for Intermountain Health Care (IHC) despite commitment and attention to share clinical information across settings and among clinicians. This study measures the extent of the disparity of data elements across three independent data systems in current use. A sample of relevant data elements was selected across systems covering prenatal, labor and delivery, and newborn intensive care units (NICU). The findings revealed only 17% of these sample data elements had compatible structure across all three systems. The implications from differences in granularity, missing data, and duplicate data entry, include diminished data quality, greater risk for medical error, increased costs of integration and inefficient use of clinician time. Retrospective guidelines for managing conceptual context and granularity are given to assist in designing an integrated longitudinal patient electronic medical record.

Delivery of Health Care, Integrated↗
PubMed2004

The Kola Birth Registry and perinatal mortality in Moncegorsk, Russia.

BACKGROUND: A population-based birth registry has been set up for the Arctic town of Moncegorsk in north-western Russia. In this investigation, the quality and the content of the registry are assessed and the perinatal mortality (PM) rates in the period 1973-97 estimated. MATERIAL AND METHOD: Enrollment in the Kola Birth Registry (KBR) involved the retrospective inclusion of all births with at least 28 weeks of gestation in Moncegorsk in the period 1973-97. The data in the registry were assessed for data entry errors, completeness of data and population coverage. The annual PM rates were estimated for live- and stillborns with at least 28 weeks of gestation. RESULTS: The KBR contains detailed information about the newborn, delivery, pregnancy and mother for 21 214 births by women from Moncegorsk, covering at least 96% of all the births by the population in the period studied. No records were missing data for gender and birth date of the newborn, and more than 99.9% of the records contained data about gestational age and birthweight. Data concerning the mothers' employment were missing in 0.4% of the records. The annual PM rate fell from more than 20 to less than 10 deaths per 1000 births during this period. CONCLUSION: The KBR provides an extensive data source useful for case-control and register-based prospective studies, and constitutes the first such compilation in Russia. The homogeneity of the population in Moncegorsk makes it advantageous for epidemiological investigations. The PM rate in Moncegorsk was lower than the overall rate in Russia.

Female↗
PubMed1999

National birthweight percentiles by gestational age for twins born in Australia.

OBJECTIVE: To develop national charts of birthweight percentiles by gestational age and infant sex for liveborn twins born in Australia. METHODOLOGY: National data on live twin births to non-Indigenous Australian-born mothers during 1991-94 were derived from perinatal data collected by midwives in each State and Territory. RESULTS: During 1991-4 there were 20,075 liveborn twin infants. Of these births, missing data included: birthweight 36 (0.2%) births, gestational age 95 (0.5%) births, and sex (missing or indeterminate) 13 (0.06%) births. These births were excluded from the study. An additional 0.6% births were excluded because the recorded birthweights were extreme outliers for the recorded gestational ages. Forty-seven per cent of live twin births were preterm (< 37 weeks). At all gestational ages, the median birthweight of male twins was higher than that of female twins. At model gestational age of 38 weeks, the difference in the median birthweight was 130 g. CONCLUSIONS: The charts produced as a result of the study provide birthweight percentiles by gestational age for twins based on national data in Australia. They provide current population norms for the use of Australian clinicians and researchers.

Adult↗
PubMedDate not supplied

Inference methods for saturated models in longitudinal clinical trials with incomplete binary data.

In the longitudinal studies with binary response, it is often of interest to estimate the percentage of positive responses at each time point and the percentage of having at least one positive response by each time point. When missing data exist, the conventional method based on observed percentages could result in erroneous estimates. This study demonstrates two methods of using expectation-maximization (EM) and data augmentation (DA) algorithms in the estimation of the marginal and cumulative probabilities for incomplete longitudinal binary response data. Both methods provide unbiased estimates when the missingness mechanism is missing at random (MAR) assumption. Sensitivity analyses have been performed for cases when the MAR assumption is in question.

Algorithms↗
PubMedDate not supplied

Gestational age reporting and preterm delivery.

This study examines recent trends in the reporting completeness and quality of gestational age estimates derived from the date of the last normal menses (DLNM) as reported in South Carolina vital records from 1974 to 1985. Noteworthy improvements in the completeness of reporting emerged during this period with a decline from 31.1 percent missing information in 1974 to 6.6 percent missing in 1985. Completeness of reporting and strategies for imputing values for missing data were analyzed for their impact on the calculation of the percentage of preterm live births. The results indicate that the underreporting of gestational age can lead to marked underestimation of the preterm percentage in a population and to misinterpretation of trends in these percentages. Based on the results of this analysis, it is recommended that preterm percentages be based on cases with DLNM gestational age values between 20 and 50 weeks. Since cases with missing or implausible gestational age data have a greater risk of a poor pregnancy outcome, these findings emphasize the importance of identifying both the completeness of data reporting and the use of imputation and deletion strategies when employing population-based DLNM data to calculate gestational age related indicators.

Adolescent↗
PubMed1997

Comparative calibration without a gold standard.

Comparative calibration is the broad statistical methodology used to assess the calibration of a set of p instruments, each designed to measure the same characteristic, on a common group of individuals. Different from the usual calibration problem, the true underlying quantity measured is unobservable. Many authors have shown that this problem, in general, does not have a unique solution. Most commonly used assumptions to obtain a unique solution are (i) one instrument is the gold standard (that is, unbiased) and (ii) the measurement errors of the p instruments are independent. Such constraints, however, may not be valid for many clinical applications, for example, the universal standardization project for dual X-ray absorptiometry (DXA) scanners. In this paper, we propose a new approach to resolve the comparative calibration problem when a gold standard is unavailable. Instead of the usual assumptions, we use external information in addition to data from the p instruments, to solve the problem. We address statistical estimation, hypothesis testing and missing data problems. We apply the new method specifically to the universal standardization project data where a group of individuals have been measured for bone mineral density (BMD) by three DXA scanners. We compare the results of the new method to currently used methods and show that they have better statistical properties.

Absorptiometry, Photon↗
PubMed2002

Recombinant human insulin-like growth factor I (rhIGF-I) for amyotrophic lateral sclerosis/motor neuron disease.

BACKGROUND: Trophic factors, including recombinant human insulin-like growth factor I have been postulated as possible disease modifying therapies for amyotrophic lateral sclerosis. Randomised clinical trials of recombinant human insulin-like growth factor I in amyotrophic lateral sclerosis to date have yielded conflicting results. OBJECTIVES: The main objective of this review was to examine the efficacy of recombinant human insulin-like growth factor I in amyotrophic lateral sclerosis. Occurrence of adverse events has also been reviewed. SEARCH STRATEGY: A search was carried out using the Cochrane Neuromuscular Disease Group register for randomised clinical trials of recombinant human insulin-like growth factor I in amyotrophic lateral sclerosis. Enquiries were also made of authors of randomised clinical trials as well as the manufacturers of recombinant human insulin-like growth factor I regarding any other randomised clinical trials which had not yet been published. SELECTION CRITERIA: Types of studies: all randomised controlled clinical trials involving recombinant human insulin-like growth factor I treatment of amyotrophic lateral sclerosis. TYPES OF PARTICIPANTS: Adults with a clinical diagnosis of definite or probable amyotrophic lateral sclerosis according to the El Escorial Criteria. Types of interventions: Treatment with recombinant human insulin-like growth factor I or placebo. Types of outcome measures: Primary: Change in Appel Amyotrophic Lateral Sclerosis Rating Scale (AALSRS) total score with 0.1mg/kg/day of recombinant human insulin-like growth factor I after nine months treatment. Secondary: Change in AALSRS with recombinant human insulin like growth factor I 0.1mg/kg/day and 0.05mg/kg/day at 1, 2, 3, 4, 5, 6, 7, 8, 9 months, change in quality of life (Sickness Impact Profile scale), survival and adverse events. DATA COLLECTION AND ANALYSIS: We identified two randomised clinical trials. Each reviewer graded them for methodological quality. Data were extracted and entered by the lead reviewer and checked by the other two. Some missing data had to be regenerated by calculations based on ruler measurements of data presented in published graphs. MAIN RESULTS: The primary outcome measure was change in disease progression as determined by the Appel ALS Rating Scale total score with 0.1 mg/kg/day of recombinant human insulin-like growth factor I subcutaneously after nine months treatment. The level of significance was lower in the European trial which compared 59 patients on placebo with 124 on insulin-like growth factor I 0.1 mg/kg/day (weighted mean difference -3.30, 95%CI -8.68 to 2.08) than in the North American trial which compared 90 patients on placebo with 89 on recombinant human insulin-like growth factor I 0.05 mg/kg/day 89 patients and 87 patients on 0.1mg/kg/day (weighted mean difference -6.00, 95%CI -10.99 to -1.01). The combined analysis from both randomised clinical trials showed a weighted mean difference of -4.75 (95% CI -8.41 to -1.09) favouring the treated group. The secondary outcome measures showed similar trends favouring recombinant human insulin-like growth factor I but these did not reach significance at the five per cent level. Similarly the data with the 0.05mg/kg/day dose showed trends favouring recombinant human insulin-like growth factor I at all time points but did not reach significance at the five per cent level at any point. Evaluation of adverse events showed an increased risk of injection site reactions/inflammation with recombinant human insulin-like growth factor I (relative risk 2.53, 95% CI 1.40 to 4.59). The drug was otherwise safe and well tolerated. REVIEWER'S CONCLUSIONS: Recombinant human insulin-like growth factor I may be modestly effective but the evidence currently available is insufficient for a definitive assessment. Further randomised clinical trials need to be done.

Amyotrophic Lateral Sclerosis↗
PubMed2002

Nutrition support for bone marrow transplant patients.

BACKGROUND: Bone marrow transplantation involves the administration of toxic chemotherapy and infusion of marrow cells. After treatment, patients can develop a poor appetite, mucositis and gastrointestinal failure, leading to malnutrition. To prevent this, parenteral nutrition (PN) support is the first choice but is associated with an increased risk of infection. Enteral nutrition (EN) is an alternative, as is the addition of substrates e.g. glutamine to enteral and parenteral solutions. However, the relative effectiveness of these treatments is not clear. OBJECTIVES: To determine the efficacy of EN or PN support for patients receiving a bone marrow transplant. SEARCH STRATEGY: Trials were identified by searching the Cochrane Library (Issue 4, 2000 ), MEDLINE (1966-2000), EMBASE (1988-2000) and CINAHL (1982-2000 ). Reference lists of identified trials and conference proceedings were searched for relevant reports. Date of the most recent search: 2000. SELECTION CRITERIA: RCTs that compared one form of nutrition support with another, or control, for bone marrow transplant patients were included. DATA COLLECTION AND ANALYSIS: Thirty five reports were identified, 11 were excluded. Two reviewers extracted data from 24 studies; 16 were allocated to four interventions: oral glutamine versus placebo; PN and glutamine versus standard PN; PN versus IV hydration; PN versus EN. Eight studies were other interventions. Data were collected on participants' characteristics; adverse effects; neutropaenia; % change in body weight; graft versus host disease; and survival. Trialists were contacted for unreported data. MAIN RESULTS: Two studies (82 subjects) found that glutamine mouthwash reduced days of neutropaenia (6.82 days, 95% CI (1.67-11.98) p=0.009) compared with placebo. Three studies (103 subjects) showed that patients receiving PN with glutamine had a reduced hospital stay, 6.62 d (95% CI 3.47, 9.77, P=0.00004) compared with patients receiving standard PN. Two studies (73 subjects) indicated that patients receiving PN plus glutamine had a reduced incidence of positive blood cultures (OR 0.23, 95% CI 0.08-0.65, p=0.006) compared to those receiving standard PN. One study, (25 subjects) showed patients receiving PN had a higher incidence of line infections (odds ratio 21.23, 95% CI 4.15,108.73, P=0.0002) compared to those receiving standard IV fluids. There were no evaluable data to compare PN with EN. REVIEWER'S CONCLUSIONS: Lack of evaluable data means that the relative effectiveness of EN versus PN cannot be evaluated. Further studies and missing data from completed trials need to be retrieved. Studies comparing PN with glutamine versus standard PN suggest that patients leave hospital earlier, and experience a reduced incidence of positive blood cultures, than those receiving standard PN. Patients with gastrointestinal failure should consider PN with the addition of glutamine if enteral feeding is not possible.

Bone Marrow Transplantation↗
PubMed2003

Percutaneous transluminal rotational atherectomy for coronary artery disease.

BACKGROUND: Percutaneous transluminal coronary rotational atherectomy (PTCRA) debulks atherosclerotic plaque from coronary arteries using an abrasive burr. On rotation, the burr selectively removes hard tissue. OBJECTIVES: To assess the effects of PTCRA for coronary artery disease in patients with non-complex and complex lesions (e.g., ostial, long, or diffuse lesions or those arising from in-stent restenosis) of the coronary arteries. SEARCH STRATEGY: We searched the Heart Group specialised register, the Cochrane Library to Issue 2, 2001, and MEDLINE, CINAHL, EMBASE and Current Contents to December 2002 and reviewed reference lists for relevant articles. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials of PTCRA compared with placebo, no treatment or another intervention and excluded cross-over trials. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two authors. We asked authors of trials to provide information when missing data was encountered. Statistical summaries used risk ratios (RR) and weighted mean differences. MAIN RESULTS: We included 9 trials enrolling 3,066 patients. There was no evidence of the effectiveness of PTCRA in non-complex lesions. In complex lesions, there were no statistically significant differences in restenosis rates at 6 months (relative risk 1.00; 95% confidence interval 0.83 to 1.20) and 1 year (relative risk 1.21; 95% confidence interval =0.95 to 1.55) in those receiving PTCRA with adjunctive PTCA (PTCRA/PTCA) compared to those receiving PTCA alone. Morphological characteristics distinguishing complex lesions have not been examined in parallel-arm randomised controlled trials. There is equivocal evidence of the effectiveness of PTCRA in in-stent restenosis. Compared to angioplasty alone, PTCRA/PTCA did not result in a statistically significant increase in the risk of major adverse cardiac events (myocardial infarction, emergency cardiac surgery or death) during the in-hospital period (relative risk 1.19; 95% confidence interval =0.78 to 1.83). Compared to angioplasty, PTCRA was associated with 9 times the risk of an angiographically-detectable vascular spasm (relative risk 9.23; 95% confidence interval 4.61 to 18.47), 4 times the risk of perforation (relative risk 3.87; 95% confidence interval 0.82 to 18.21) and about 2 times the risk of transient vessel occlusions (relative risk 2.28; 95% confidence interval 1.00, 5.19) while angiographic dissections (relative risk 0.49; 95% confidence interval 0.33 to 0.75) and stents used as a bailout procedure (relative risk 0.38; 95% confidence interval 0.22 to 0.65) were less common. REVIEWER'S CONCLUSIONS: When conventional PTCA is feasible, PTCRA appears to confer no additional benefits. There is limited published evidence and no long-term data to support the routine use of PTCRA in in-stent restenosis. In certain circumstances (e.g., patients ineligible for cardiac surgery, those with architecturally complex lesions, or those with lesions that fail PTCA), PTCRA may achieve satisfactory revascularisation in subsequent procedures.

Angioplasty, Balloon, Coronary↗
PubMed2002

Pulmonary rehabilitation for chronic obstructive pulmonary disease.

BACKGROUND: The widespread application pulmonary rehabilitation in chronic obstructive pulmonary disease (COPD) should be preceded by demonstrable improvements in function attributable to the programs. This review updates that reported by Lacasse et al Lancet 1996; 748:1115-1119. OBJECTIVES: To determine the impact of rehabilitation on health-related quality of life (QoL) and exercise capacity in patients with COPD. SEARCH STRATEGY: The 14 randomized controlled trials (RCTs) included in the original meta-analysis were included. Additional RCTs were identified from the Cochrane Airways Group's registry of COPD RCTs using the strategy: [exp, lung diseases, obstructive] and [exp, rehabilitation or exp, exercise therapy] and [research design or longitudinal studies or evaluation study or randomized controlled trial]. Abstracts presented at American Thoracic Society 1980-2000, American College of Chest Physicians 1980-2000 and European Respiratory Society 1987-2000 were also searched. SELECTION CRITERIA: RCTs of rehabilitation in patients with COPD in which quality of life (QoL) and/or functional (FEC) or maximal (MEC) exercise capacity were measured. Rehabilitation was defined as exercise training for at least 4 weeks with or without education and/or psychological support. Control groups received conventional community care without rehabilitation. DATA COLLECTION AND ANALYSIS: Weighted mean differences (WMD) were calculated using a random-effects model. Missing data from the primary study reports were requested from the authors. MAIN RESULTS: 23 RCTs met the inclusion criteria. Statistically significant improvements were found for all the outcomes. In three important domains of QoL (Chronic Respiratory Questionnaire scores for Dyspnea, Fatigue and Mastery), the effect was larger than the minimal clinically important difference of 0.5 units using this instrument. For example Dyspnoea score: WMD 0.98 units, 95% Confidence Interval (95% CI) 0.74 - 1.22 units; n=9 trials. For FEC and MEC, the effect was small and a little below the threshold of clinical significance for the 6- minute walking distance: WMD 49 m, 95% CI: 26 - 72 m; n=10 trials. REVIEWER'S CONCLUSIONS: Rehabilitation relieves dyspnea and fatigue and enhances patients' sense of control over their condition. These improvements are moderately large and clinically significant. The average improvement in exercise capacity was modest. Rehabilitation forms an important component of the management of COPD.

Dyspnea↗