Use of beta-blocker therapy in older patients after acute myocardial infarction in Ontario.

BACKGROUND: Despite its proven efficacy, beta-blocker therapy remains underused in elderly patients after myocardial infarction (MI). The objectives of this study were to identify undertreated groups of seniors and to determine whether older and frailer patients are being selectively dispensed low-dose beta-blocker therapy. METHODS: From a comprehensive hospital discharge database, all people aged 66 years or more in Ontario who survived an acute MI between April 1993 and March 1995 were identified and classified into those who did not receive beta-blocker therapy and those dispensed low, standard or high doses of this agent. Logistic regression models were used to study the effect of age, sex, comorbidity, potential contraindications to beta-blocker therapy and residence in a long-term-care facility on the odds of not being dispensed a beta-blocker. Among beta-blocker users, the odds of being dispensed low relative to standard or high doses of this agent were evaluated. RESULTS: Of the 15,542 patients, 7549 (48.6%) were not dispensed a beta-blocker. Patients 85 years of age or more were at greater risk of not receiving beta-blocker therapy (adjusted odds ratio [OR] 2.8, 95% confidence interval [CI] 2.5-3.2) than were those 66 to 74 years. Having a Charlson comorbidity index of 3 or greater was associated with an increased risk of not receiving beta-blocker therapy (adjusted OR 1.5, 95% CI 1.3-1.8) compared with having lower comorbidity scores. Patients who resided in a long-term-care facility were at increased risk of not being prescribed beta-blocker therapy (adjusted OR 2.6, 95% CI 2.0-3.4). Among the 5453 patients with no identifiable contraindication to beta-blocker therapy, women were significantly less likely than men to receive this agent (p = 0.005). Of the 6074 patients who received beta-blockers, 2248 (37.0%) were dispensed low-dose therapy. Patients aged 85 years or more had an increased risk of being dispensed low-dose therapy (adjusted OR 1.6, 95% CI 1.3-2.0) compared with those aged 66 to 74 years. Compared with those who had the lowest comorbidity scores, patients with the highest comorbidity scores were more likely to be dispensed low-dose beta-blocker therapy (adjusted OR 1.3, 95% CI 1.0-1.8). INTERPRETATION: Almost half of Ontario patients aged 66 or more who survived an MI, particularly those who were older or frailer, did not receive beta-blocker therapy. Among those dispensed beta-blocker therapy, older and frailer patients were more frequently dispensed low-dose therapy.     

Cytokines in chronic heart failure: possible interaction in the neurohormonal and the cytokine system at the cAMP level?

In recent years, the pathophysiological concept of chronic heart failure (CHF) has changed from an isolated hemodynamic view to a more complex concept involving neuroendocrine and inflammatory pathways. New therapeutic strategies, such as beta-blocker therapy, are based on these new concepts and provide clinical evidence for a clinical benefit in patients with CHF. The survival benefit of beta-blocker therapy in CHF has been related to neurohumoral regulation. Thus, evidence evolved showing that following beta-blocker therapy cytokine levels in CHF patients are altered. We have shown that the levels of soluble TNF receptor type 2 correlated well with cAMP in leukocytes. Data from clinical studies in adult and infant CHF patients have demonstrated that beta-blocker therapy is accompanied by altered cytokine, cytokine antagonist, and/or soluble cytokine receptor levels. These alterations may result from a dysregulated interaction of beta-adrenergic pathways and the cytokine system, and are possibly related to cAMP-dependent regulation of the release or shedding of these mediators.     

Tuberculosis chemoprophylaxis.

The incidence of tuberculosis in the United States, after decreasing for many years, has recently begun to climb at an alarming rate. This rise is due mainly to excess cases in high-risk groups including human immunodeficiency virus-infected patients, the elderly, the foreign born, and the homeless. In the United States tuberculosis has been associated with a 10% mortality despite adequate treatment. The tuberculin skin test is a safe and inexpensive test for detecting tuberculous infection. To improve its predictive value the diagnostic criteria for classifying a positive reaction have recently been revised. High-risk populations should be screened to identify those persons who would most benefit from preventive treatment. Isoniazid therapy taken for 6 to 12 months is a safe and highly effective means of preventing tuberculous infection from developing into active disease. The most worrisome toxicity of isoniazid, fatal hepatitis, is extremely rare; when patients are monitored closely the incidence of death from hepatotoxicity is less than 0.01%.     

Fatal myocardial infarction in the Scottish adjuvant tamoxifen trial. The Scottish Breast Cancer Committee.

OBJECTIVE--To investigate the incidence of fatal myocardial infarction in women in the two randomised arms of the Scottish adjuvant tamoxifen trial. DESIGN--Retrospective review of hospital notes to determine with the greatest possible certainty women who had died of an acute myocardial infarction. SETTING--Scottish Cancer Trials Office, the University of Edinburgh. PATIENTS--1070 postmenopausal women with operable breast cancer who were randomised to receive either adjuvant tamoxifen for five years or until relapse (539 patients) or tamoxifen for at least six weeks on the confirmation of first recurrence (531 patients). MAIN OUTCOME MEASURES--Incidence of fatal myocardial infarction in women with no known or suspected systemic cancer. RESULTS--Of the 200 women who died in the adjuvant tamoxifen arm of the trial, 44 were free of cancer at death and 10 of these died of myocardial infarction. In the observation arm 251 women died, of whom 61 showed no evidence of systemic cancer and 25 had a fatal myocardial infarction. The incidence of fatal myocardial infarction in the two groups was significantly different (chi 2 = 6.88, p = 0.0087). CONCLUSION--Tamoxifen given for at least five years as adjuvant therapy for breast cancer seems to have a cardioprotective oestrogen-like effect in postmenopausal women.     

Engineered recombinant peanut protein and heat-killed Listeria monocytogenes coadministration protects against peanut-induced anaphylaxis in a murine model

Peanut allergy (PNA) is the major cause of fatal and near-fatal anaphylactic reactions to foods. Traditional immunotherapy using peanut (PN) protein is not an option for PNA therapy because of the high incidence of adverse reactions. We investigated the effects of s.c. injections of engineered (modified) recombinant PN proteins and heat-killed Listeria monocytogenes (HKLM) as an adjuvant on anaphylactic reactions in a mouse model of PN allergy. PN-allergic C3H/HeJ mice were treated s.c. with a mixture of the three major PN allergens and HKLM (modified (m)Ara h 1-3 plus HKLM). The effects on anaphylactic reactions following PN challenge and the association with Ab levels and cytokine profiles were determined. Although all mice in the sham-treated groups exhibited anaphylactic symptoms with a median symptom score of 3, only 31% of mice in the mAra h 1-3 plus HKLM group developed mild anaphylaxis, with a low median symptom score of 0.5. Alterations in core body temperature, bronchial constriction, plasma histamine, and PN-specific IgE levels were all significantly reduced. This protective effect was markedly more potent than in the mAra h 1-3 protein alone-treated group. HKLM alone did not have any protective effect. Reduced IL-5 and IL-13, and increased IFN-gamma levels were observed only in splenocytes cultures from mAra h 1-3 plus HKLM-treated mice. These results show that immunotherapy with modified PN proteins and HKLM is effective for treating PN allergy in this model, and may be a potential approach for treating PNA.     

Pregnancy in women with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is increasingly being diagnosed in pregnant women. Women with HCM generally tolerate pregnancy well. The risk is however higher in women who are symptomatic before pregnancy or in those with severe left ventricular outflow tract obstruction. The incidence of arrhythmias does not appear to be increased during pregnancy and maternal mortality is low. Prior to conception, women with HCM should have a risk assessment as well as genetic counselling. During pregnancy beta-blockers should be continued and the judicious use of diuretics may be required to treat symptoms of dyspnoea. A vaginal delivery with regional anaesthesia is usually appropriate. Women should be managed by a specialist multidisciplinary team.     

Late divergence of survival curves in cancer immunotherapy trials: interpretation and implications

Late divergence of survival curves of treated patients and controls is commonly seen in successful cancer immunotherapy trials. Although late survival curve divergence may be caused by a delayed action of therapy, it may also be related to early effects of the treatment. We suggest that late survival divergence most often reflects a specific benefit of therapy for patients who suffer from a comparatively slow progression of disease. The occurrence of delayed survival curve divergence has important implications for the statistical analysis of immunotherapy trials. Thus, it leads to non-proportional hazard ratios that make commonly used statistical tests, e.g., the logrank test, suboptimal. It is therefore suggested that the statistical analysis of immunotherapy trials primarily should be based on a test that compares the survival curves at or after a prespecified, fixed, late time point.     

ANTIBIOTIC ANAPHYLAXIS

Anaphylactic reactions following the injection of penicillin or other antibiotics have increased greatly during the past several years. These untoward reactions to penicillin were infrequent during the first nine years of penicillin therapy and there can be no doubt that hypersensitivity to these drugs is developing in many people. Therefore promiscuous use of them is to be condemned. It is safer not to use antibiotics parenterally in patients with allergic conditions such as bronchial asthma. The further use of a particular antibiotic should be avoided if the patient has previously shown any hypersensitivity to that drug.A questionnaire was answered by more than 1,000 California physicians who reported that over 300 patients had severe anaphylactic reactions from parenteral penicillin and streptomycin. There were seven deaths.Since the antibiotics should still be used when needed, prevention of anaphylaxis is of fundamental importance. The frequency of these reactions can be greatly reduced by the use of antihistaminic solutions combined with the antibiotics. Treatment of these shock-like reactions demands the prompt administration of epinephrine intramuscularly, antihistaminic solutions intravenously and oxygen.     

Ultra-short acting beta-blockers: a proposal for the treatment of the critically ill patient

Beta-blockade is of proven value in the therapy of acute myocardial infarction but, unfortunately, may produce cardiac failure by removal of needed sympathetic support. The long duration of action of available blockers (hours) makes reversal of failure a complicated problem and precludes rapid modification of therapy to match changing autonomic conditions. To improve the safety and efficacy of beta-blockade in this setting we have developed the concept of ultra-short beta-blockade and have identified a novel beta-blocker (ASL-8052) which possesses a duration of action less than 15 minutes. This compound is cardioselective and possesses efficacy in an animal model of acute myocardial infarction. It, therefore, appears to be suitable for rapid attainment of controlled levels of beta-blockade via intravenous infusion and rapid recovery from beta-blockade if required by the clinical situation. The compound should, therefore, be useful for safe therapy in critically ill cardiac patients.     

Immunotherapy using algal‐produced Ara h 1 core domain suppresses peanut allergy in mice

Peanut allergy is an IgE‐mediated adverse reaction to a subset of proteins found in peanuts. Immunotherapy aims to desensitize allergic patients through repeated and escalating exposures for several months to years using extracts or flours. The complex mix of proteins and variability between preparations complicates immunotherapy studies. Moreover, peanut immunotherapy is associated with frequent negative side effects and patients are often at risk of allergic reactions once immunotherapy is discontinued. Allergen‐specific approaches using recombinant proteins are an attractive alternative because they allow more precise dosing and the opportunity to engineer proteins with improved safety profiles. We tested whether Ara h 1 and Ara h 2, two major peanut allergens, could be produced using chloroplast of the unicellular eukaryotic alga, Chlamydomonas reinhardtii. C. reinhardtii is novel host for producing allergens that is genetically tractable, inexpensive and easy to grow, and is able to produce more complex proteins than bacterial hosts. Compared to the native proteins, algal‐produced Ara h 1 core domain and Ara h 2 have a reduced affinity for IgE from peanut‐allergic patients. We further found that immunotherapy using algal‐produced Ara h 1 core domain confers protection from peanut‐induced anaphylaxis in a murine model of peanut allergy.     

Breast reconstruction with postmastectomy radiation therapy: current issues

Two recent trials have demonstrated superior locoregional control, disease-free survival, and overall survival in node-positive breast cancer patients with the addition of postmastectomy radiation therapy to mastectomy and chemotherapy. Based on these results, there has been an increased use of postmastectomy in patients with early-stage breast cancer. The inability to determine which patients will require postmastectomy radiation therapy has increased the complexity of planning for immediate breast reconstruction. There are two potential problems with performing an immediate breast reconstruction in a patient who will require postmastectomy radiation therapy. One problem is that postmastectomy radiation therapy can adversely affect the aesthetic outcome of an immediate breast reconstruction. Several studies have evaluated the outcomes of breast reconstructions that were performed before radiation therapy and have revealed a high incidence of complications and poor aesthetic outcomes. Furthermore, these studies have found that often an additional flap is required to restore breast shape and symmetry. The other potential problem is that an immediate breast reconstruction can interfere with the delivery of postmastectomy radiation therapy. During planning for immediate breast reconstruction, it is imperative to carefully review the stage of disease and the likelihood the patient will require postmastectomy radiation therapy. Unfortunately, the ability to detect and predict the presence or extent of axillary lymph node involvement is limited, and the need for postmastectomy radiation therapy is usually not known until after mastectomy. In all cases of decision making regarding possible postoperative radiation therapy and whether or not to perform immediate breast reconstruction, the situation should be discussed at a multidisciplinary conference or addressed among the various medical, surgical, and radiation teams, with active participation by the patient. Immediate breast reconstruction probably should be avoided in patients known to require postmastectomy radiation therapy and delayed until it is certain the therapy will be needed in patients who may require the therapy.     

Immunotherapy in the treatment of lymphoma

Relapsed or refractory non-Hodgkin's lymphomas, especially diffuse large B-cell lymphoma as well as relapsed or refractory Hodgkin lymphomas are hard-to-treat diseases. Patients who do not respond to initial therapy or experience relapse are treated with salvage regimens, and if eligible for aggressive therapy, treatment is continued with high-dose chemotherapy and autologous stem cell transplantation. Current therapy options can cure substantial numbers of patients, however for some it is still an uncurable disease. Numerous new drugs and cell therapies are being investigated for the treatment of relapsed or refractory lymphomas. Different types of immunotherapy options have shown promising results, and some have already become the standard of care. Here, we review immunotherapy options for the treatment of lymphoma and discuss the results, positions, practical aspects, and future directions of different drugs and cellular therapies for the treatment of this disease.     

The effect of thymic substances on T circulating cells of patients treated for Hodgkin's disease

Forty-one patients with Hodgkin's disease staged as IA(4), IIA/B(4/6) IIIA/B(6/9) and IVA/B(3/9) who had had radiotherapy (subtotal nodal irradiation (STNI) or total nodal irradiation (TNI), or combined one (STNI/TNI plus chemotherapy MOPP or MOPP/ABVD) have been enrolled consequently and randomized to receive thymic hormone (17 patients) or pentapeptide treatment (14 patients) for 3-6 months at the end of the therapeutic regimens. In all patients severe immunodeficiency evaluated either as leukopenia (WBC less than 4000/mm3) or lymphocytopenia (lymphocytes less than 1500/mm3) or CD3 and CD2 cell reduction, or imbalance of helper/suppressor (H/S) ratio have been documented before starting thymic therapy. Different results by immunorestorative therapy have been registered according to the entity of immunodeficiency. In fact in the group of 15 patients with severe lymphopenia (lymphocytes less than 1000/mm3) either the thymic hormone or the synthetic drug produced a significant increase of all subsets examined: CD3-CD2-CD4-CD8 without or with minimal influence on H/S ratio, due to the increase of absolute lymphocytes count. In the remaining patients with mild or no lymphopenia the two drugs resulted ineffective on T cells. Comparing the overall group of patients who received thymic therapy with a control group of patients who did not, an advantage in terms of recruitment of T cell compartment has been observed in the former group when mean values are compared. According to the clinical impact of the immunotherapy with thymic substances on these patients, a significant decrease in incidence of herpes virus infection (HVI) has been observed in patients who had had thymic therapy compared with the incidence of HVI in the control group (18% versus 53.8%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Treatment of Acute Lymphoblastic Leukaemia: PRELIMINARY REPORT BY THE LEUKAEMIA COMMITTEE AND THE WORKING PARTY ON LEUKAEMIA IN CHILDHOOD

One hundred and ninety-one cases of acute lymphoblastic leukaemia were entered in a trial in which, for five months, all received cytotoxic therapy with prednisolone, vincristine, mercaptopurine, L-asparaginase, and methotrexate (the latter in high dosage followed by folinic acid). Patients were then randomized to receive immunotherapy (B.C.G.), twice-weekly methotrexate, or no further treatment.One hundred and seventy-seven patients (93%) achieved full remission and at the time of analysis, 26 months from the beginning of the trial, 143 were still alive, including 70 in their first remission. Median “post-intensive” remission lengths were 17 weeks (no treatment), 27 weeks (B.C.G.), and 52 weeks (methotrexate). The prolongation of remission by methotrexate was most evident in those patients with low initial white cell counts. B.C.G. seemed to cause lymphocytosis but was without other conspicuous effect. The incidence of toxic reactions is reported, including an unusually low rate of anaphylaxis with L-asparaginase.These preliminary results are discussed and compared with those of similar trials.     

双特异性抗体构建在肿瘤临床治疗中的应用

双特异性抗体(Bispecific antibody,BsAb)是具有两个不同抗原结合位点的抗体,可分为含Fc段和不含Fc段的BsAb,不同结构的BsAb具有不同的特点和应用领域.相比于传统的单克隆抗体,BsAb的灵敏度和特异性更高.更重要的是,BsAb具有募集免疫细胞、双重阻断信号通路等功能,在免疫诊断和治疗中扮演重...     

胃癌的过继性免疫治疗研究进展

胃癌是目前世界上发病率及致死率较高的恶性肿瘤之一,在东亚地区尤其显著。针对胃癌的治疗手段仍是传统的手术联合化疗、放疗为主,尽管靶向药物治疗提供了新的选择,但其对晚期胃癌的疗效仍然有限。胃癌的免疫治疗作为独特的治疗手段,在近十多年发展较为活跃,特别是过继性免疫治疗手段不断有创新。过继性免疫治疗主要依赖回输具有抗肿瘤活性的细胞,目前回输的细胞由具有非特异性抗肿瘤作用向具有特异性抗肿瘤作用演变,特别是嵌合性抗原T细胞治疗的出现,为进展期胃癌患者提供了有一种潜在的选择。本文对胃癌过继性免疫治疗中采用的不同免疫活性细胞的作用机制、临床应用等进行总结,并针对其不足提出利用基因工程技术增强治疗靶向性、降低免疫逃逸的研究方向。     

Fatal isoniazid-induced hepatitis. Its risk during chemoprophylaxis.

Isoniazid chemoprophylaxis has long been known to be a highly effective means of preventing silent tuberculous infections from spreading to active disease. There has been much controversy, however, about the risk it carries for fatal hepatotoxicity. In this article I review the rate of fatal isoniazid-induced hepatitis during chemoprophylaxis that is done according to current monitoring guidelines. Information was obtained from a MEDLINE literature search and a survey of tuberculosis control officers in large metropolitan areas throughout the country. Data were included of patients who were monitored according to the American Thoracic Society''s guidelines or who were treated after 1983 when the guidelines were published. The pooled results of the published studies showed no hepatotoxic deaths in 20,212 patients in whom prophylaxis was started. The unpublished data showed 2 deaths in 182,285 patients, for a combined rate of 0.001% (2 of 202,497). The death rate for those older than 35 years was estimated to be 0.002% (1 of 43,334). This rate is significantly lower than was previously estimated and should be used to reevaluate the benefit of preventive therapy for tuberculin-reactive patients older than 35. The risk of fatal isoniazid-induced hepatitis is negligible for all ages when patients are routinely monitored for liver toxicity.     

Effect of Beta-Blocker Therapy on the Risk of Infections and Death after Acute Stroke – A Historical Cohort Study

BackgroundInfections are a frequent cause for prolonged hospitalization and increased mortality after stroke. Recent studies revealed a stroke-induced depression of the peripheral immune system associated with an increased susceptibility for infections. In a mice model for stroke, this immunosuppressive effect was reversible after beta-blocker administration. The aim of our study was to investigate the effect of beta-blocker therapy on the risk of infections and death after stroke in humans.Methods625 consecutive patients with ischemic or hemorrhagic stroke, admitted to a university hospital stroke unit, were included in this historical cohort study. The effect of beta-blocker therapy on post-stroke pneumonia, urinary tract infections and death was investigated using multivariable Poisson and Cox regression models.Results553 (88.3%) patients were admitted with ischemic stroke, the remaining 72 (11.7%) had a hemorrhagic stroke. Median baseline NIHSS was 8 (IQR 5–16) points. 301 (48.2%) patients received beta-blocker therapy. There was no difference in the risk of post-stroke pneumonia between patients with and without beta-blocker therapy (Rate Ratio = 1.00, 95%CI 0.77–1.30, p = 0.995). Patients with beta-blocker therapy showed a decreased risk for urinary tract infections (RR = 0.65, 95%CI 0.43–0.98, p = 0.040). 7-days mortality did not differ between groups (Hazard Ratio = 1.36, 95%CI 0.65–2.77, p = 0.425), while patients with beta-blocker therapy showed a higher 30-days mortality (HR = 1.93, 95%CI 1.20–3.10, p = 0.006).ConclusionsBeta-blocker therapy did not reduce the risk for post-stroke pneumonia, but significantly reduced the risk for urinary tract infections. Different immune mechanisms underlying both diseases might explain these findings that need to be confirmed in future studies.     

Perforated Peptic Ulcer

Because no large series of perforated peptic ulcers has been reported from Canada, 402 cases from the Ottawa Civic Hospital were reviewed to study this dramatic disorder.The incidence was 15 per 100,000 population annually, or one in every 1000 hospital admissions.The incidence in females and the elderly in this series was higher than reported elsewhere. The risk of perforation increased with age, being greatest after 55; this was not due to an excess of chronic ulcers in older patients, indicating that ageing is an etiological factor.As the mortality of perforated peptic ulcer—20%—had remained unchanged over the years, fatal cases were studied to see if changes should be made in the management of this condition. The mortality for patients undergoing operation was 7.5%. Patients treated conservatively because their general condition was poor, died. Fifteen patients, in whom an incorrect diagnosis was made, died. More aggressive therapy and greater efforts at diagnosis might have saved some of these patients.     

Statin-induced myositis: a commonly encountered or rare side effect?

PURPOSE OF REVIEW: Statins are well established as first-line agents for cholesterol lowering in cardiovascular disease, with accumulating evidence supporting their initiation and guidelines recommending treatment to lower LDL levels. Although generally well tolerated with few side effects, including headaches and gastrointestinal symptoms, concerns are raised regarding myopathy, which may lead to fatal rhabdomyolysis. This review examines current evidence on statin interactions, mechanism of injury and toxicity. RECENT FINDINGS: Significant myopathy is rare with an incidence of less than 0.5% of patients. Statin side effects may be dose-related, associated with other drug interactions that interfere with statin metabolic pathways through cytochrome p450 pathways or glucuronidation, or related to co-morbidities. Several theories have suggested that statin myotoxicity may be due to intracellular cholesterol depletion, or interference with oxidative phosphorylation pathways. Exact mechanisms are yet to be fully defined. Individuals with mixed dyslipidaemia may require combination therapy to achieve target lipid levels. No large-scale randomized trials have yet reported on the safety of combination therapy, although more recent studies may shed some light when they report. CONCLUSION: As most individuals on statins are 'high-risk' patients, they tend to be on multiple agents for cardiovascular disease which may interact with their statin. Progression of myalgia or myositis to rhabdomyolysis is rare (one in 30-100,000 patient-years of exposure), but if progressive muscle symptoms are ignored then fatalities can occur. When prescribing statins, physicians should be alert to potential risks and educate patients to report any potentially significant symptoms.