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[Stroke--possibilities for prevention].

The practice of stroke medicine varies enormously. This is not just because of variable resources, access to services and preferences among patients, clinicians, medical centres, governments and societies, but also often because of poor evidence about the effectiveness and cost of many components of stroke care. Although the past 20 years have seen a huge increase in randomised controlled trials, the results have not always had much influence on clinical practice, perhaps because many trials used confusing outcome measures or were too small (limited statistical power) or because the findings could not easily be generalised. Our purpose is to review the best evidence for stroke treatment and prevention.

Clinical Trials as Topic↗

Therapeutic value of alpha-4 integrin blockade in inflammatory bowel disease:the role of natalizumab.

Lymphocyte infiltration into the intestinal tract in Crohn's disease is mediated by the interaction between alpha(4) integrin, expressed on lymphocytes, and its ligand mucosal vascular addressin cell-adhesion molecule-1 (MADCAM-1), expressed on the endothelial cells of the microvasculature in inflamed intestinal tract. Natalizumab, a recombinant, humanised monoclonal antibody against alpha(4) integrin was effective in Crohn's disease in a Phase II, randomised, controlled trial. The highest response rate and remission rates were 71 and 44% at 6 weeks, respectively, after two infusions of 3 mg of natalizumab administered 4 weeks apart. Natalizumab was well-tolerated in this study. The Phase III trial results are awaited.

Antibodies, Monoclonal↗

Safety evaluation of the drugs available to prevent malaria.

All drugs used for malaria prophylaxis have common adverse effects, in addition to rare and/or severe adverse effects. For many of the drugs in current use, the common adverse effects include neuropsychiatric harms. This property makes these drugs unpopular with tourists and business travellers, most of whom will be well at the start of chemoprophylaxis. Drugs available to prevent malaria have not been rigorously researched in terms of the phenomenology of their unwanted effects. Consequently, prescribers are not well placed to give useful information to travellers on the incidence, natural history and avoidability of the harms they may experience from malaria chemoprophylaxis. There is some evidence that the adverse effects of mefloquine may be a post-hepatic syndrome caused by drug-induced liver damage with, in some users, symptomatic thyroid disturbance. However, confusion in the interpretation of the scientific evidence has led to conflicting messages regarding the safety of mefloquine and other antimalaria drugs, and to incorrect self-therapy by individual travellers, sometimes with fatal outcomes. In this review, the existing knowledge base for the safety of drugs currently used to prevent malaria is described along with present designs for future studies that would allow a rigorous safety assessment of candidate chemoprophylactic agents and of new drugs introduced to prevent malaria. There is an urgent need for internationally-agreed, evidence-based malaria prevention guidelines. These guidelines should be explicitly linked to the best available research evidence (normally systematic reviews of trials and individual randomised trials) and should highlight gaps in the knowledge base as priority areas for research.

Adult↗

Side effects of using nitrates to treat angina.

Nitrates are very effective antianginal and anti-ischaemic agents. Provision of a long nitrate-free interval or low plasma nitrate levels prior to the morning dose prevents the loss of clinical efficacy by preventing the development of tolerance. However, side effects during nitrate therapy are common. Headache is the most common side effect of nitrates; often dose-related and reported by up to 82% of patients in placebo-controlled trials. Nearly 10% of patients are unable to tolerate nitrates due to disabling headaches or dizziness. In others, headaches are mild-to-moderate in severity and either resolve or diminish in intensity with continued nitrate therapy. Nitrate-induced hypotension is common, but often asymptomatic. In rare instances, nitrate-induced hypotension is severe and accompanied by marked slowing of the heart rate and syncope. Use of nitrates in patients who experience syncope after administration of nitrates is contraindicated. Nitrates rarely cause coronary steal and myocardial ischaemia. Nitrate rebound may occur and patients may experience nocturnal anginal episodes during intermittent therapy with nitroglycerin patches. Administration of nitrates is contraindicated with concomitant use of phosphodiesterase-5 inhibitors used for the treatment of erectile dysfunction, as combination therapy may lead to profound hypotension and even death. There are disturbing observational reports in the literature that continuous, prolonged use of nitrates may lead to increased mortality and recurrent myocardial infarctions. Large, randomised, placebo-controlled studies are needed to confirm or refute these reports; until then, the use of nitrates to treat angina is here to stay.

Angina Pectoris↗

[The justification for laparoscopic appendectomy].

Laparoscopic appendicectomy (LA), in contrast to open appendicectomy (OA), is not generally accepted as the treatment of choice for suspected appendicitis because it is technically difficult, not readily available everywhere, takes longer to perform, is expensive, and is associated with an increased incidence of intra-abdominal abscesses. However, LA has shown a superior outcome compared to an OA in terms of less postoperative pain, earlier hospital discharge, quicker return to normal activity and work and decreased incidence of wound infection. Furthermore, a diagnostic laparoscopy is valuable in case of an equivocal diagnosis of appendicitis especially in premenopausal women and obese individuals because it allows a thorough examination of the whole abdomen under direct vision. It, therefore, permits accurate diagnosis and hence reduces the negative appendectomy rate. Nevertheless, before endorsing routine and widespread use of LA, it is essential that this technique is critically evaluated in well designed, controlled, randomised, prospective trials clearly showing major benefits to the patient in terms of quicker hospital discharge, reduced postoperative pain, decreased wound infection and early return to full activities.

Appendectomy↗

Sleep and breathing.

This paper reviews some of the recent advances in the sleep apnoea/hypopnoea syndrome. Sleep apnoea has recently been shown to be familial and in some of these patients this is due to retroposition of the maxilla and mandible. There is now good evidence that individuals with sleep apnoea have an increased risk of road accidents and increasing, although not yet 100% robust, evidence that they have an increased frequency of systemic hypertension. The last few years have seen a large number of randomised controlled trials of CPAP therapy which have shown clear evidence that CPAP improves symptoms, subjective sleepiness, objective sleepiness, cognitive function, IQ, mood, quality of life and driving ability. Evidence that CPAP influences cardiovascular and cerebrovascular outcomes is awaited.

Humans↗

Randomised controlled trials in nursing and midwifery: an interview with Maralyn Foureur. Interview by Pamela J. Wood.

Randomised controlled trials are considered to be one of the best research designs for determining effective care in the clinical setting. Relatively few randomised controlled trials, however, have been carried out in nursing or midwifery practice, so few examples of the practical realities of this research methodology are readily accessible. This is the sixth article in a series based on interviews with nursing and midwifery researchers, designed to offer the beginning researcher a first-hand account of the experience of using particular methodologies. This article focuses on the randomised controlled trial as experienced by Maralyn Foureur (RGON, RM, BA, Grad Dip Clin Epidem, PhD) who used this methodology to demonstrate the effectiveness of a continuity of care model in midwifery practice.

Continuity of Patient Care↗

The challenge of evaluating surgical procedures.

All new interventions and procedures must be properly assessed in comparison to the currently accepted method(s). It is unethical not to do so. The optimum method is by Randomised Controlled Trial (RCT). This is ideally suited to the testing of drugs because the trial can usually be double blind and placebo controlled. RCTs are less commonly used for the evaluation of new surgical techniques. There are valid and invalid reasons for this and these are discussed.

Clinical Trials as Topic↗

[Interactions between radiation and hormonal therapy in breast cancer: simultaneous or sequential treatment].

BACKGROUND: Combining radiation and hormone therapy (administration of selective estrogen receptor modulators) has become common clinical practice in recent years for receptor positive breast cancer. Little is known about a possible interaction of both treatment modalities if they are given simultaneously. Tamoxifen (antiestrogen molecule, triphenylethylene derivative) may theoretically render cancer cells less responsive to radiotherapy arresting hormone-receptor-positive cells in G0/G1 phase and increase the risk of breast and lung fibrosis stimulating the secretion of transforming growth factor beta in human fibroblasts. PURPOSE: This article reviews the published data to assess the impact of sequencing of hormonal and radiation therapy on outcomes in breast cancer. METHODS: Computerised searches for publications debating the sequencing of hormonal therapy relative to radiation therapy were done using MEDLINE data. RESULTS: Results of tamoxifen experiments with cell culture regarding radioprotection of tumour clonogens are conflicting. In contrast to in vitro results, in animal studies no protective effect of tamoxifen was observed. In one in vitro study, letrozole (non-steroid selective aromatase inhibitor) had a radiosensitizing effect on breast-cancer lines. No randomised clinical trials to date have studied sequencing of tamoxifen or other selective estrogen receptor modulators and radiotherapy. Results from retrospective clinical studies which included treatment arms with and without tamoxifen showed reduction in tumour recurrence with tamoxifen. Some of these studies have noted increased risk of lung and breast fibrosis with tamoxifen with radiotherapy. Results of three articles examined the effect of tamoxifen sequence showed no adverse effect on local control or survival in sequential versus concurrent tamoxifen and radiation patients. One of the three studies also assessed the risk of complications with respect to the timing of tamoxifen with radiotherapy. There was no difference in the rates of complications between the two groups. The association of radiation and selective aromatase inhibitors or aromatase inactivators has not been addressed in clinical studies. CONCLUSIONS: Combined application of tamoxifen and radiotherapy improves survival and local control in breast cancer. Available clinical studies do not indicate that the simultaneous application of tamoxifen and radiotherapy is disadvantageous, as was suggested by some of the in vitro studies. The risk of subcutaneous breast and lung fibrosis might be slightly increased if tamoxifen is given simultaneously with radiotherapy. Both treatment modalities should be started early after surgery. There is no sufficient evidence to withhold tamoxifen administration during irradiation of breast cancer. The issue of optimal sequencing of hormonal and radiotherapy should be addressed in randomised clinical trials.

Animals↗

[Hormonal supplements for postmenopausal women: no evidence of protection against cardiovascular disease].

Atherothrombotic cardiovascular disease is a leading cause of death in women, especially in the postmenopause. It is controversial whether postmenopausal hormone replacement therapy is protective with regard to cardiovascular disease. On the one hand, observational studies consistently show that the risk of cardiovascular disease is 35 to 50% lower among users of hormonal replacement than among non-users. In addition, hormonal replacement is associated with an improvement of the lipid profile and several other potentially beneficial effects. On the other hand, two recent placebo-controlled randomised trials did not find evidence in favour of cardiovascular protection by hormonal replacement. This discrepancy may be explained by insufficient adjustment for lifestyle factors in observational studies and insufficient consideration of methodological flaws in experimental studies, both of which lead to an overestimation of the protective effect of hormonal replacement. Hormonal replacement may affect the pathophysiology of atherothrombosis in several ways, both positive and negative. Progress in this field requires the isolation of the positive effects.

Aged↗

Field efficacy of a 10 per cent pyriproxyfen spot-on for the prevention of flea infestations on cats.

The clinical application of a new method for using the insect growth regulator, pyriproxyfen, for controlling flea populations in cat-owning homes is evaluated for the first time. In a multicentric, controlled and randomised trial, 107 flea-infested cats were treated with a minimum dose of 10 mg/kg bodyweight pyriproxyfen as a 10 per cent spot-on application on two occasions, with a three-month interval between doses. For comparison, 99 cats received lufenuron suspension orally, once a month, for six months. Flea counts decreased significantly over time in each group and were significantly lower in the pyriproxyfen group than in cats treated with the reference product. The percentage of 'zero-flea' cats increased from 49 per cent on day 30 to 88 per cent on day 180 in the pyriproxyfen group and from 30 to 71 per cent in the lufenuron group at the same time points (P<0.05). Appropriately timed topical applications of pyriproxyfen, therefore, offer a method of flea control in the domestic environment.

Administration, Cutaneous↗

[Chemoradiotherapy and anal canal cancer].

Local control and sphincter preservation are the two challenges of anal canal cancer treatment. These tumors are radio- and chemo-sensitive and treatment moved from surgical approach, with abdominoperineal resection, to definitive radiation therapy with or without concurrent chemotherapy. Randomised trials proved the benefit of combined modality with chemoradiotherapy and of mitomycine C (MMC) compared with radiotherapy alone, with a toxic death rate of about 2%. Indications of chemoradiotherapy are locally advanced tumor T2 > or = 4 cm, T3-4 or N1-3 but the best modalities of combined treatment are still under debate. Standard chemotherapy is 5 flurouracile (5FU) + MMC, but cisplatinum (CDDP) is an effective and well tolerated substitute for MMC. Favourable results with CDDP-containing regimen in term of toxicity and carcinologic control have been reported in phase II and retrospective studies. Total radiation dose, overall duration of radiation therapy, duration of the gap and indications of additional boost are not clear, but it is demonstrated that overall duration of treatment should be as short as possible to improve the therapeutic radio. Phase II and III studies are ongoing, to evaluate the best chemotherapy regimen between 5FU+MMC and 5FU+CDDP, the benefit of neoadjuvant or maintenance chemotherapy and the interest of increased total dose. Next future could be the utilisation of oral 5FU. This article is a review of past randomised trials, phases II and retrospective study on radiochemotherapy of anal canal carcinoma.

Antineoplastic Combined Chemotherapy Protocols↗

New strategies in anaemia management: ACORD (Anaemia CORrection in Diabetes) trial.

Anaemia is a key component of diabetic nephropathy, but its importance has only recently been recognised. Recombinant human erythropoietin (epoetin) is an established treatment for renal anaemia, and may help to reduce complications associated with diabetic nephropathy, such as cardiovascular disease. The limited experience with the use of epoetin in this patient group prompts the urgent need for clinical data on anaemia correction in early diabetic nephropathy, particularly with regard to benefits on cardiovascular risk reduction. The Anaemia CORrection in Diabetes (ACORD) study will investigate the effects of anaemia correction on cardiac structure and function in patients with early diabetic nephropathy. This 15-month multicentre study will recruit 160 adult patients with diabetes, mild or moderate chronic kidney disease (with creatinine clearance >or=30 ml/min at screening) and moderate anaemia (haemoglobin [Hb], 10.5-13.0 g/dl). Patients will be randomised to one of two groups: the early treatment group will receive subcutaneous epoetin beta (NeoRecormon) at study entry to maintain target Hb levels of 13-15 g/dl, while the control group will reflect current practice and will not receive epoetin therapy until Hb levels decline below 10.5 g/dl. The primary efficacy variable, change in left ventricular mass index, will be evaluated at 15 months following randomisation; secondary efficacy variables will include changes in cardiac structure and function over the study period. The ACORD study should provide valuable information on the benefits of anaemia correction in patients with early diabetic nephropathy. The study will also increase awareness of the importance of treating anaemia associated with diabetes.

Anemia↗

[Calcaneal fractures--the most frequent tarsal fractures].

Operative treatment of intra-articular calcaneal fractures with anatomical reduction and early mobilisation has lead to a considerable improvement of the functional results of these severe injuries over the recent two decades. New tendencies like modified approaches tailored according to the vascular anatomy, arthroscopic control of joint reduction in conjunction with open or percutaneous procedures, early flap coverage for severe open fractures or closed fractures with full thickness skin necrosis, the use of interlocking plates that further minimises the need of bone grafting and subtalar arthrolysis at the time of hardware removal for fibrous overgrowth have the potential for further improvement of the outcome. The observation from several comparative studies that operative treatment leads to superior results in displaced intra-articular calcaneal fractures has been qualified in a recent prospective, randomised multicentre trial. This paper presents and the authors' experience with the demanding operative treatment of these fractures together with new developments aiming at improving the clinical results.

Arthroscopy↗

[MUSTIC trial].

The atrio-bi-ventricular pacing has been used for hemodynamic improvement since 1994, and the MUSTIC trial is the first controlled study assessing this concept. It collected 67 patients with severe and stable heart failure with optimised medical therapy, with sinus rhythm and without any traditional indication for pacing. After two periods of three months with blinded randomisation and cross-over, the bi-ventricular pacing mode showed its superiority to the inactive mode concerning all study endpoints, for example with an improvement of the functional capacity of 23% assessed by the 6-minutes-walk test. Thus the MUSTIC trial opens up the way for morbidity and mortality studies.

Aged↗

One-year angiotensin-converting enzyme inhibition plus mycophenolate mofetil immunosuppression in the course of early IgA nephropathy: a multicenter, randomised, controlled study.

Angiotensin converting-enzyme inhibition (ACEI) is a widely accepted treatment during established renal diseases and beneficial effects have also been reported in IgA nephropathy (IgAN). Immunosuppression with myco-phenolate mofetil (MMF) has recently been introduced in the treatment of immune-mediated renal diseases showing promising results. Preliminary clinical reports are also suggestive that MMF is effective in severe forms of IgAN. We propose a randomised prospective trial aimed to compare long-term renal survival of early IgAN in the course of ACEI therapy with or without MMF immunosuppression.

Adolescent↗

Treatment of Langerhans cell histiocytosis--evolution and current approaches.

Optimal treatment of Langerhans cell histiocytosis remains problematic. The absence of controlled studies and the lack of standard diagnostic and evaluation criteria have impeded therapeutic progress even though knowledge of basic aspects of LCH have advanced. Historical analysis of outcome suggests little improvement until very recently, but marked differences in outcome according to extent of disease. Consequently, major and now successful efforts have been made to stratify LCH patients into different 'risk groups'. Recent findings suggest that combination chemotherapy for multisystem disease is beneficial and that VP-16 is a useful new agent for treating LCH, despite controversies regarding its side effects. The first randomised international treatment study, LCH-1, being conducted by the Histiocyte Society, should resolve some of these controversies. Other experimental therapies may be considered for children with severe, unresponsive LCH.

Biological Factors↗

Prognostic and predictive relevance of microsatellite instability in colorectal cancer.

Microsatellite instability (MSI) is the phenotypic hallmark of a deficient DNA mismatch-repair system, observed in 10-20% of sporadic colorectal cancers (CRC). Since the prognostic and predictive value of this genetic alteration has been assessed mainly in non-randomised, uncontrolled studies, we investigated the potential of MSI to predict patient survival and response to adjuvant chemotherapy in tumour specimens from a randomised trial of the Swiss Group for Clinical Cancer Research (SAKK) that tested the value of 5-fluorouracil/mitomycin adjuvant chemotherapy. MSI status was determined in matched normal and tumour tissue samples from 160 patients using a panel of 9 microsatellite markers. There was no correlation between high frequency MSI (MSI-H) and overall (OS) or disease-free survival (DFS) in the untreated control group of patients (HR=1.13, p=0.80; and HR=0.89, p=0.81, respectively). Furthermore, MSI-H phenotype did not predict for a larger benefit of adjuvant chemotherapy on OS or DFS (HR=0.49, p=0.41; HR=0.49, p=0.41, respectively), making a potential value of this molecular marker as a predictive factor in CRC unlikely. Our data do not confirm the prognostic relevance of MSI-H status in colorectal cancer patients found in some other studies. In addition, microsatellite instability did not correlate with the extent of chemotherapy benefit, although we observed a statistically non-significant favourable impact of 5-FU-based treatment in the MSI-H group compared to MSI-L/MSS patients. Larger prospective randomised trials are required to conclusively establish a potential clinical significance of MSI in colorectal cancer.

Antineoplastic Combined Chemotherapy Protocols↗