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PubMed1996

[Large trials in the secondary prevention of stroke].

To date, no drug has been demonstrated as efficacious in the treatment of acute ischemic stroke. Therefore, primary and secondary prevention play a fundamental role. Besides adequate control of risk factors, trials and meta-analyses have demonstrated that both medical and surgical therapy are effective in secondary prevention of stroke. In patients with atherothrombotic transient ischemic attack (TIA) or minor stroke and carotid stenosis > 70%, surgical therapy (endarterectomy) is the treatment of choice, while antiplatelet drugs are the elective treatment in the case of stenosis < 70%. Acetylsalicylic acid is the first choice medical treatment, but the optimal dosage is still a matter of debate. Ticlopidine has an efficacy similar to that of aspirin, but shows a certain number of side effects; recently a European study has shown the efficacy of dipyridamole, and the superiority of the combination dipyridamole-aspirin vs low-dose aspirin. In the secondary prevention of cardioembolic stroke, oral anticoagulants have higher efficacy than antiplatelet drugs, at least in selected groups of patients.

Anticoagulants↗

PubMed1996

Renal protection and angiotensin converting enzyme inhibition in microalbuminuric type I and type II diabetic patients.

BACKGROUND: Many studies have emphasized the role of antihypertensive drugs and in particular angiotension converting enzyme (ACE) inhibitors in the retardation of diabetic nephropathy. Although these studies have focused predominantly on patients with overt proteinuria, more recently a number of investigators have explored the role of ACE inhibitors in both type I and type II diabetic patients with an earlier phase of diabetic renal disease known as microalbuminuria. These agents are now being considered as renoprotective agents not only in hypertensive patients but also in those with 'normal' blood pressure. Initially, studies in type I diabetic patients showed that ACE inhibition was effective in retarding the increase in albuminuria which was observed in placebo treated groups. More recently, several multi-centre placebo controlled studies have been performed suggesting that prolonged treatment not only reduced albuminuria but also preserved renal function. The role of ACE inhibition in microalbuminuric type II diabetic patients is less well characterised although several studies have recently described beneficial effects of ACE inhibition on albuminuria and possibly on renal function. REVIEW: Although ACE inhibitors have been clearly shown to reduce urinary albumin excretion in diabetic patients, the issue as to whether they confer a specific benefit over other classes of antihypertensive agents remains controversial. Several meta-analyses have suggested that ACE inhibitors are more potent at decreasing albuminuria or proteinuria than other antihypertensive agents, for a given reduction in blood pressure. The Melbourne Diabetic Nephropathy Study Group has instituted a study which is placebo-controlled and is confined to normotensive type I and type II diabetic patients. The ACE inhibitor perindopril has been compared not only with placebo but also with the dihydropyridine calcium channel blocker, nifedipine. Preliminary analysis reveals that after 12 and 24 months of treatment, perindopril is more effective in reducing albuminuria than placebo or nifedipine. CONCLUSION: ACE inhibitors are a promising class of antihypertensive agents in diabetic patients with microalbuminuria. These drugs should be considered as first line agents in such patients, even in the absence of systemic hypertension.

Albuminuria↗

PubMed1997

Health outcomes associated with antihypertensive therapies used as first-line agents. A systematic review and meta-analysis.

OBJECTIVE: To review the scientific evidence concerning the safety and efficacy of various antihypertensive therapies used as first-line agents and evaluated in terms of major disease end points. DATA SOURCES: MEDLINE searches and previous meta-analyses for 1980 to 1995. DATA SELECTION: We selected long-term studies that assessed major disease end points as an outcome. For the meta-analysis, we chose placebo-controlled randomized trials. For randomized trials using surrogate end points such as blood pressure, we selected the largest studies that evaluated multiple drugs. Where clinical trial evidence was lacking, we relied on information from observational studies. DATA SYNTHESIS: Diuretics and beta-blockers have been evaluated in 18 long-term randomized trials. Compared with placebo, beta-blocker therapy was effective in preventing stroke (relative risk [RR], 0.71; 95% confidence interval [CI], 0.59-0.86) and congestive heart failure (RR, 0.58; 95% CI, 0.40-0.84). The findings were similar for high-dose diuretic therapy (for stroke, RR, 0.49; 95% CI, 0.39-0.62; and for congestive heart failure, RR, 0.17; 95% CI, 0.07-0.41). Low-dose diuretic therapy prevented not only stroke (RR, 0.66; 95% CI, 0.55-0.78) and congestive heart failure (RR, 0.58; 95% CI, 0.44-0.76) but also coronary disease (RR, 0.72; 95% CI, 0.61-0.85) and total mortality (RR, 0.90; 95% CI, 0.81-0.99). Although calcium channel blockers and angiotensin-converting enzyme (ACE) inhibitors reduce blood pressure in hypertensive patients, the clinical trial evidence in terms of health outcomes is meager. For several short-acting dihydropyridine calcium channel blockers, the available evidence suggests the possibility of harm. Whether the long-acting formulations and the nondihydropyridine calcium channel blockers are safe and prevent major cardiovascular events in patients with hypertension remains untested and therefore unknown. CONCLUSION: Until the results of large long-term clinical trials evaluating the effects of calcium channel blockers and ACE inhibitors on cardiovascular disease incidence are completed, the available scientific evidence provides strong support for the current national guidelines, which recommend diuretics and beta-blockers as firstline agents and low-dose therapy for all antihypertensive agents.

Adrenergic beta-Antagonists↗

PubMed1997

[Behavior and cognitive treatments for insomnia. An alternative to pharmacotherapy].

OBJECTIVE: To familiarize family physicians with cognitive and behavioural treatments for insomnia. DATA SOURCES: MEDLINE was searched from 1983 to 1995 and Psychlit from 1974 to 1995 using the key words "behaviour therapy," "cognitive therapy," "phototherapy," and "insomnia." STUDY SELECTION: We chose randomized trials and meta-analyses on the treatment of insomnia. Information was extracted on time-lag before sleep, frequency and duration of wakeful periods during the night, consumption of hynotics, and subjects' own assessment of their sleep before and after treatment. SYNTHESIS: The most effective interventions were relaxation training, sleep restriction, and stimulus control. Practising good sleeping habits was only somewhat effective and should always be used in conjunction with other interventions. CONCLUSION: Stimulus control for insomnia has been demonstrated to be effective when used by primary care physicians. Other nonpharmacologic treatments should be evaluated in a similar manner.

Behavior Therapy↗

PubMed1997

Cognitive-behavioral therapy for panic disorder: current status.

Controlled clinical trials evaluating cognitive-behavioral approaches for panic disorder are rapidly accumulating. In the aggregate, these studies suggest substantial efficacy for cognitive-behavioral approaches in both the short and long term. Summaries and meta-analyses of these results are briefly described, but new evidence is also presented indicating that, in this chronic condition, patients continue to experience some exacerbations and remissions over the long term. Current attempts to evaluate combination psychosocial and pharmacologic approaches are described as well as the beginnings of efforts to develop more powerful treatments for panic disorder with or without agoraphobia.

Alprazolam↗

PubMed1997

Updated results of the trials of screening mammography.

Most analysts agree that screening women for breast cancer can reduce the death rate by at least 25% to 30%. In 1993 the National Cancer Institute created a great deal of confusion among women and their physicians by withdrawing support for screening women aged 40 to 49 years. The controversy arose as a result of the inappropriate and scientifically insupportable analysis of data from the early results from the randomized controlled trials of screening. Despite that the trials were not designed to evaluate women aged 40 to 49 years as a separate subgroup and that they lacked the statistical power to permit legitimate analysis of this subgroup, women aged 40 to 49 years were analyzed separately, and erroneous conclusions were drawn. In an effort to justify these conclusions, other data have been analyzed improperly to try to suggest that significant screening parameters change at menopause or at the age of 50, whereas the facts do not support any abrupt change. There are no parameters such as breast density, cancer detection rate, or positive predictive value that change abruptly at age 50 or any other age. With longer follow-up of the screening trial data and the commensurately greater statistical power, the most recent meta-analyses provide statistically significant proof that screening can reduce the death rate from breast cancer for women aged 40 to 49 years by at least 24%.

Adult↗

PubMed1997

[Acute lumbar disk displacement with nerve root compression. Indications for peridural steroid injection].

The rationale and indication, but also the efficacy and limitation of lumbar epidural corticosteroid injection in patients suffering from acute lumbosacral radicular pain are explained. Epidural administration of corticosteroids with longterm effect and bupivacaine by a translumbar approach in patients suffering from acute low back pain and sciatica causes an immediate, persistent pain relief and a more prompt regression of nerve root compression compared to patients just treated by bed rest and analgesics. The state of the art is based on recent meta-analyses and the understanding of the pathophysiology of discal hernia which includes inflammation. Contemporary concepts and data from recent reviews are summarized to elucidate current recommendations and suggestions for the management of patients with acute sciatica. The postulate of an application performed by an experienced anaesthesiologist is stressed. Advantages of this invasive form of therapy include reduction of addictive analgesic drugs, decreased time of absolute immobilisation, respectively strict bed rest, and of hospitalisation.

Acute Disease↗

PubMed1996

Clinical studies of effects of nitrogen oxides in healthy and asthmatic subjects.

Traffic and cooking and heating using unventilated gas appliances are the major sources for environmental exposures to nitrogen oxides. The nitrogen oxides of importance for health effects are nitrogen dioxide (NO2), and maybe the two derivatives nitric and nitrous acid (HNO3 and HNO2). Due to this, human exposure studies on NO2 have been performed intensively during the last decades. Nitric oxide (NO) is quantitatively the major pollutant, but is not very toxic and may even be used in treatment of certain conditions of respiratory insufficience. Major lung function effects shown in humans are a decrease in the forced expiratory volume in the first second (FEV1), increased specific airway resistance (SRaw), and increased responsiveness in bronchial provocation tests. Studies have been performed primarily on healthy and asthmatic subjects, but only asthmatic subjects show these reactions at levels relevant to exposures found in indoor and outdoor environments. Other effects found in animal studies and epidemiological studies like decreased mucociliary function, increased susceptibility to infections have not been proven in humans and are therefore still on debate. Human studies have furthermore shown that antioxidants like vitamin C and E may prevent effects of NO2, which is explained by that the mechanism of NO2-action is the oxidation of airway phospholipids. A large inconsistency in the results of the studies makes it very difficult to conclude about dose-response relationships and about no observed effect levels (NOEL). Single study observations and results of meta-analyses have indicated a biphasic dose-response relationship. However, such a relationship is hard to explain and need to be investigated further. Several other explanations, e.g. the limited statistical power of the studies, may exist and will be discussed.

Asthma↗

PubMedDate not supplied

[Nifedipine and coronary insufficiency: reasons for controversy].

Meta-analyses of Furberg's original data (after correction of two minor errors) were performed using six different methods. Only three of them gave significant results at p < 0.05. The sensitivity analysis showed that taking into account some of the criticisms applied to the original meta-analysis did not change the results. When all the criticisms were considered together, the 95 per cent confidence interval of the odds ratio for mortality was [0.96; 1.31] instead of [1.06; 1.37] originally (p = 0.14 and p = 0.03 respectively), and the dose excess mortality relationship stressed by Furberg disappeared. When the selection of the studies to be entered in a meta-analysis is not straightforward, a sensitivity analysis should be performed.

Angina Pectoris↗

PubMedDate not supplied

Paradise regained: insights into coronary heart disease prevention from recent clinical trials and basic research.

Many of the uncertainties regarding the place of lipid lowering in the prevention of coronary heart disease have recently been resolved. Some of the newer findings are reviewed, and the scope for a revised clinical approach examined. The results of trials of lipid lowering, based on clinical end-points and particularly on angiographic end-points, and their meta-analyses are discussed. The close relation between coronary-angiographic and clinical outcomes is reviewed in relation to recent advances in understanding of the underlying arterial pathology, and possible underlying mechanisms are proposed. The variables predictive of progression of coronary artery disease, including nutrient intake, are examined. The management of hyperlipidaemia requires that treatment and therapeutic goals are consonant with the patient's cardiovascular risk; for this purpose, clinical and biochemical assessment of risk may be enhanced by angiographic and non-invasive methods to detect potentially-infarctogenic atherosclerotic lesions.

Anticholesteremic Agents↗

PubMed1997

The drug trials that have influenced our clinical practice in acute ischaemic stroke.

With the possible exception of aspirin, there are still no drug treatments which have been found to be so effective in randomised controlled trials, and meta-analyses of such trials, that they should be used routinely in acute ischaemic stroke. The evidence on thrombolysis is tantalising but with only about 3500 randomised patients in all the trials put together it is too early to say how, and for whom, this promising treatment should be used, particularly bearing in mind the risk of intracranial haemorrhage; the evidence so far is enough to persuade us to enter our patients into further large trials of thrombolysis but it is not enough to justify this treatment in our routine clinical practice.

Fibrinolytic Agents↗

PubMed1997

Reductase inhibitor monotherapy and stroke prevention.

BACKGROUND: Epidemiologic evidence and meta-analyses of data from early clinical trials suggest that lowering the levels of cholesterol does not reduce the events of stroke. These analyses have not included more recent clinical trials using reductase inhibitors. OBJECTIVE: To conduct a meta-analysis of the effect of reducing cholesterol levels on stroke in all reported clinical trials of primary (n = 4) and secondary (n = 8) prevention of coronary heart disease that used reductase inhibitor monotherapy and provided information on incident stroke. RESULTS: Analysis of combined data from primary and secondary prevention trials showed a highly statistically significant reduction of stroke associated with the use of reductase inhibitor monotherapy (27% reduction in stroke; P = .001). Analysis of secondary prevention trials alone disclosed a similar statistically significant effect (32% reduction in stroke; P = .001). A smaller nonsignificant reduction in stroke was noted in the primary prevention trials (15% reduction in stroke; P = .48). CONCLUSIONS: Reductase inhibitors now in use for lowering cholesterol levels are more potent and have fewer side effects than the cholesterol-lowering agents previously available. They appear to reduce stroke, most notably in patients with prevalent coronary artery disease, which may be partly due to the effects of lowering the levels of cholesterol on the progression and plaque stability of extracranial carotid atherosclerosis or the marked reduction of incident coronary heart disease associated with treatment.

Adult↗

PubMed1996

[Chemotherapy for non-small cell lung cancer].

The combination of cisplatin and either a vinca alkaloid or etoposide is one of the most effective chemotherapeutic regimens for non-small cell lung cancer. Meta-analyses of clinical trials in which cisplatin-based combination chemotherapy was compared with supportive care in patients with non-resectable non-small cell lung cancer showed that the chemotherapy reduced mortality. In the last decade, new agents, including vinorelbine, edatrexate, paclitaxel, docetaxel, irinotecan, topotecan and gemcitabine, have shown promise in the treatment of non-small cell lung cancer, and new agents combined with platinum compounds have reached the level of phase III testing. Randomized studies in which radiotherapy alone was compared with radiotherapy and cisplatin-based combination chemotherapy in patients with stage III disease showed that combined treatment can prolong survival and improve long-term outcome in patients with locally advanced non-small cell lung cancer. Recently, new agents combined with radiotherapy have been tested. Regimens in which platinum compounds are combined with new agents hold promise for more successful treatment of this disease.

Antineoplastic Agents, Phytogenic↗

PubMed1997

Diagnosis and treatment of gastrointestinal bleeding secondary to portal hypertension. American College of Gastroenterology Practice Parameters Committee.

UNLABELLED: Guidelines for clinical practice are intended to suggest preferable approaches to particular medical problems as established by interpretation and collation of scientifically valid research, derived from extensive review of published literature. When data are not available that will withstand objective scrutiny, a recommendation may be made based on a consensus of experts. Guidelines are intended to apply to the clinical situation for all physicians without regard to specialty. Guidelines are intended to be flexible, not necessarily indicating the only acceptable approach, and should be distinguished from standards of care, which are inflexible and rarely violated. Given the wide range of choices in any health care problem, the physician should select the course best suited to the individual patient and the clinical situation presented. These guidelines are developed under the auspices of the American College of Gastroenterology and its practice parameters committee. These guidelines are also approved by the governing boards of American College of Gastroenterology and Practice Parameters Committee. Expert opinion is solicited from the outset for the document. Guidelines are reviewed in depth by the committee, with participation from experienced clinicians and others in related fields. The final recommendations are based on the data available at the time of the production of the document and may be updated with pertinent scientific developments at a later time. The following guidelines are intended for adults and not for pediatric patients. OBJECTIVE: To develop practice guidelines for the management of gastrointestinal bleeding in adult patients with cirrhosis and portal hypertension. METHOD: Randomized controlled trials published through October of 1993 were evaluated by members of the American College of Gastroenterology Practice Parameters Committee. Each paper was reviewed by three members of the committee and rated for quality of design by predetermined criteria. Meta-analysis of the studies for each treatment were evaluated for both outcome and quality of design and formed the basis for recommendations for treatment. Randomized controlled trials published between October of 1993 and August of 1995 have been added to update and modify the recommendations. The reader is referred to an excellent article by D'Amico et al. (The treatment of portal hypertension: A meta-analytic review. Hepatology 1995;22:332-354), which presents most of the meta-analyses reviewed by this committee. CONCLUSIONS: Once esophageal varices have been established by endoscopy as the site of bleeding, either sclerotherapy or endoscopic variceal ligation should be performed to control the bleeding episodes. Concomitant use of vasoactive drugs lowers portal pressure, potentially offers the endoscopist a clearer field in which to work, and is the only noninvasive treatment for nonesophagogastric variceal sites of bleeding related to portal hypertension. For patients failing medical therapy, the transjugular intrahepatic portasystemic shunt procedure is a reasonable alternative to an emergency surgically created shunt. Nonselective beta-adrenergic blockers are the only proven therapy for prevention of first variceal hemorrhage. Both nonselective beta-adrenergic blockers and endoscopic variceal ligation (which has replaced sclerotherapy for this indication) are effective in reducing the risk of recurrent variceal bleeding. For patients failing these approaches, selective or total shunts or, in selected patients, liver transplantation are appropriate rescue procedures.

Acute Disease↗

PubMed1997

Update on hepatic intra-arterial chemotherapy.

The use of hepatic intra-arterial (HIA) chemotherapy is based on the pharmacologic principle that the regional administration of certain drugs can lead to higher drug concentrations at the site of a tumor. This has been studied most extensively in patients with liver-only colorectal metastases. Four large randomized studies have failed to demonstrate a survival advantage of regional treatment over systemic chemotherapy, although two meta-analyses confirmed an improvement in response rate and suggest a trend toward improvement in survival. Two randomized studies have shown improved survival in patients treated with HIA chemotherapy, as compared with those given supportive care, and quality of life also appears to be superior in HIA chemotherapy recipients. The treatment employed in all of the randomized studies was hindered by substantial hepatobiliary toxicity and many surgical complications. Improved surgical techniques and newer chemotherapy combinations appear to have improved phase II results with HIA therapy, leading to a randomized trial now being conducted by the Cancer and Leukemia Group B (CALGB). The role of HIA chemotherapy in adjuvant settings and in other diseases has not been as well-studied, and such uses remain appropriate only for very selected patients. Ultimately, the regional advantage gained by the HIA route may prove to be most advantageous for the delivery of newer biologic agents.

Antineoplastic Agents↗

PubMedDate not supplied

Adverse drug reactions of DMARDs and DC-ARTs in rheumatoid arthritis.

Comprehensive meta-analyses have revealed that survival on DMARD therapy in rheumatoid arthritis can be classified according to several factors: the number of adverse drug reactions, the percentage of drop-outs, and the duration of usage, which is clearly linked to both drug efficacy and drug toxicity. When taking into account of all of these issues, the impact of each DMARD can be scored differently, but certainly the length of time on a given DMARD gives us a conclusive, clinically important overview of its overall efficacy and safety. On these grounds, studies lasting two years or more have demonstrated that, while sulphasalazine can be employed for a median length of 12 months, methotrexate treatment can be maintained for more than 5 consecutive years. Severe and life-threatening complications have been observed with all conventional DMARDs.

Antirheumatic Agents↗

PubMed1997

[Practical clinical implications of megastudies for primary prevention].

The results of different meta-analyses conducted in primary prevention have shown an insignificant difference in total mortality or coronary heart disease (CHD) mortality; and only two studies have shown differences in the incidence of CHD. The WOS study, the first study in primary prevention done with statines, observed a 20% reduction in the total cholesterol, a relative risk reduction of 31%, an absolute risk reduction of 2.4% and the number of patients who needed to be treated, to prevent coronary disease during a five year period, was 42. Subgroup analyses showed a greater benefit for high risk patients: smokers and those with peripheral vascular disease. This is why the utilization of a cardiovascular risk estimation, instead of isolated cholesterol levels or other risk factors, is currently recommended. However, it is important to bear in mind that the results of the WOS study cannot be easily extrapolated to Spain because the rates of CHD are much lower here than the ones observed in Scotland. Promotion of treatment of high risk patients with statines must be accompained by a promotion of a healthy lifestyle at both the individual and the community level.

Coronary Disease↗

PubMed1997

[Role of adjuvant chemotherapy in the treatment of soft tissue sarcoma].

Important improvements in local control with increasing function-sparing treatment have been achieved in adult soft tissue sarcomas (STS). However, the global prognosis of these diseases remains poor and 40% of patients with STS currently die of metastases within 5 years. In fact, the impact of chemotherapy remains debated, particularly in the adjuvant setting. Thirteen randomized clinical trials with no-treatment control arms have been published to assess adjuvant chemotherapy. A benefit has been demonstrated in 2 studies for overall survival, and in 5 studies when considering disease-free survival (DFS). Globally, despite large differences between studies (patient selection and treatment modalities), overall survival, DFS and local control of the chemotherapy arm were always better than those of the observed arm. These effects were also confirmed in 3 meta-analyses on published data. However, according to the preliminary results of a meta-analysis on individual patient data, overall survival does not appear to be significantly affected. Therefore, adjuvant chemotherapy for STS remains investigational. Randomized studies have to be pursued on the basis of previously performed trials in order to assess which patient group really benefits from adjuvant chemotherapy.

Actuarial Analysis↗