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Dive into the research topics where Lawrence S. Friedman is active.

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Featured researches published by Lawrence S. Friedman.


The New England Journal of Medicine | 1991

Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial.

Debra S. Echt; Philip R. Liebson; L. Brent Mitchell; Robert W. Peters; Dulce Obias-Manno; Allan H. Barker; Daniel Arensberg; Andrea Baker; Lawrence S. Friedman; H. Leon Greene; Melissa Huther; David W. Richardson

BACKGROUND AND METHODS In the Cardiac Arrhythmia Suppression Trial, designed to test the hypothesis that suppression of ventricular ectopy after a myocardial infarction reduces the incidence of sudden death, patients in whom ventricular ectopy could be suppressed with encainide, flecainide, or moricizine were randomly assigned to receive either active drug or placebo. The use of encainide and flecainide was discontinued because of excess mortality. We examined the mortality and morbidity after randomization to encainide or flecainide or their respective placebo. RESULTS Of 1498 patients, 857 were assigned to receive encainide or its placebo (432 to active drug and 425 to placebo) and 641 were assigned to receive flecainide or its placebo (323 to active drug and 318 to placebo). After a mean follow-up of 10 months, 89 patients had died: 59 of arrhythmia (43 receiving drug vs. 16 receiving placebo; P = 0.0004), 22 of nonarrhythmic cardiac causes (17 receiving drug vs. 5 receiving placebo; P = 0.01), and 8 of noncardiac causes (3 receiving drug vs. 5 receiving placebo). Almost all cardiac deaths not due to arrhythmia were attributed to acute myocardial infarction with shock (11 patients receiving drug and 3 receiving placebo) or to chronic congestive heart failure (4 receiving drug and 2 receiving placebo). There were no differences between the patients receiving active drug and those receiving placebo in the incidence of nonlethal disqualifying ventricular tachycardia, proarrhythmia, syncope, need for a permanent pacemaker, congestive heart failure, recurrent myocardial infarction, angina, or need for coronary-artery bypass grafting or angioplasty. CONCLUSIONS There was an excess of deaths due to arrhythmia and deaths due to shock after acute recurrent myocardial infarction in patients treated with encainide or flecainide. Nonlethal events, however, were equally distributed between the active-drug and placebo groups. The mechanisms underlying the excess mortality during treatment with encainide or flecainide remain unknown.


Journal of the American College of Cardiology | 1986

Fifteen Year Mortality in Coronary Drug Project Patients: Long-Term Benefit With Niacin

Paul L. Canner; Kenneth G. Berge; Nanette K. Wenger; Jeremiah Stamler; Lawrence S. Friedman; Ronald J. Prineas; William T. Friedewald

The Coronary Drug Project was conducted between 1966 and 1975 to assess the long-term efficacy and safety of five lipid-influencing drugs in 8,341 men aged 30 to 64 years with electrocardiogram-documented previous myocardial infarction. The two estrogen regimens and dextrothyroxine were discontinued early because of adverse effects. No evidence of efficacy was found for the clofibrate treatment. Niacin treatment showed modest benefit in decreasing definite nonfatal recurrent myocardial infarction but did not decrease total mortality. With a mean follow-up of 15 years, nearly 9 years after termination of the trial, mortality from all causes in each of the drug groups, except for niacin, was similar to that in the placebo group. Mortality in the niacin group was 11% lower than in the placebo group (52.0 versus 58.2%; p = 0.0004). This late benefit of niacin, occurring after discontinuation of the drug, may be a result of a translation into a mortality benefit over subsequent years of the early favorable effect of niacin in decreasing nonfatal reinfarction or a result of the cholesterol-lowering effect of niacin, or both.


Annals of Internal Medicine | 1997

Effect of Antihypertensive Drug Treatment on Cardiovascular Outcomes in Women and Men: A Meta-Analysis of Individual Patient Data from Randomized, Controlled Trials

François Gueyffier; Florent Boutitie; Jean-Pierre Boissel; Stuart J. Pocock; John Coope; Jeffrey A. Cutler; Tord Ekbom; Robert Fagard; Lawrence S. Friedman; Mitchell Perry; Ronald J. Prineas; Eleanor Schron

The effectiveness of antihypertensive drug treatment is well established and has been quantified in terms of overall reduction in the relative risk for stroke and other cardiovascular disease events [1, 2]. Risk for cardiovascular events (especially myocardial infarction) differs greatly between men and women, and these differences are not explained by other risk factors [3]. It remains unclear, however, whether the effect of antihypertensive treatment in reducing cardiovascular risk is dependent on sex. In a 1986 review, MacMahon and colleagues [4] stated that event rates, particularly those for fatal events and nonfatal myocardial infarction, were substantially lower in women than in men. The striking benefits of study treatments for the risk of fatal and non-fatal stroke were evident for both men and women. A reduction in total mortality could not be demonstrated for women, but the treatment effect for women was not significantly different from that in men, among whom there was an important and statistically significant reduction in mortality. This comment was based on the results of two trials: the Hypertension Detection and Follow-up Program (HDFP) [5] and the Medical Research Council trial of treatment of mild hypertension (MRC35-64) [6]. In their 1991 analysis of data from these trials plus data from the European Working Party on High Blood Pressure in the Elderly (EWPHE) trial [7] and the Australian therapeutic trial in mild hypertension [8], Anastos and colleagues [9] concluded that the few data that do exist suggest that gender, like race and age, significantly influences the natural course of hypertension and the response to treatment . The data regarding aggressive treatment of white women are equivocal; there is concern that such treatment may actually be harmful. Since these reviews were published, reports of three additional trials of antihypertensive treatment in older hypertensive men and women have appeared in print: the Medical Research Council trial of treatment of hypertension in older adults (MRC 65-74) [10], the Systolic Hypertension in the Elderly Program (SHEP) [11], and the Swedish Trial in Old Patients with Hypertension (STOP) [12]. More recently, other reviewers have stated that antihypertensive medications do not appear to be as effective in women as in men [13] and that when treated, women often achieve less benefit than do men [14]. The INDANA (INdividual Data ANalysis of Antihypertensive intervention trials) project [15] offers the opportunity to provide more evidence on the effects of antihypertensive treatment in women; results are based on individual patient data from all of the randomized, controlled trials mentioned in the preceding paragraphs. The two main objectives of the current study are to quantify the average treatment effect in each sex separately and to determine whether treatment effect differs significantly between women and men. Methods The INDANA project (whose rationale, objectives, and methods are described in detail elsewhere [15]) is a collaboration of representatives from most of the large randomized, controlled trials of antihypertensive drug treatment. Its results are derived from centralized files of the baseline and follow-up data available for all patients enrolled in the trials. The Trials Our report is based on seven trials [5-710-12, 16] (Table 1) in which both men and women were enrolled. The inclusion criteria for the trials in the INDANA project are discussed elsewhere [15]. In summary, the steering group of the project made the following decisions: The data from the Australian trial [8] were not included in the analysis because separate outcomes are not available without censoring bias; the EWPHE trial [7] data were included only for the analysis of mortality end points (separate nonfatal outcomes are not available without censoring bias); and the data from HDFP [5] were considered in a sensitivity analysis (analysis was done with and without these data because of the originality of the trial design, which compared specific antihypertensive care systems with usual care). The data from the Veterans Administration and National Heart, Lung, and Blood Institute feasibility trial [17] are available in the INDANA database but have not yet been submitted to control and extraction procedures. Thus, these data were not used in our analysis. Because this trial has only a small weight in terms of patient-years and observed events, its exclusion is unlikely to change the results presented here. Table 1. Main Characteristics of the Seven Antihypertensive Drug Trials That Enrolled Men and Women* Outcomes According to the INDANA protocol, seven outcomes were analyzed: 1) fatal strokes; 2) fatal and nonfatal strokes, excluding transient ischemic attacks; 3) fatal coronary events [including sudden death, which was defined as unexpected and unexplained death occurring within a maximal interval of 24 hours after symptom onset]; 4) fatal and nonfatal major coronary events (using criteria for major coronary heart disease obtained from patient histories in HDFP) [1]; 5) cardiovascular-related mortality, including death from pulmonary thromboembolism; 6) major cardiovascular events [combining the second, fourth, and fifth outcomes and excluding such minor cardiovascular events as angina pectoris, intermittent claudication, or nonfatal congestive heart failure]; and 7) total mortality. Statistical Analysis Summarized data (number of patients and number of events) were extracted from the INDANA database by sex and by trial according to the intention-to-treat principle. For the group assigned to receive active treatment, the odds ratio compared with controls was estimated by sex for each outcome according to the Peto method [18]. The odds ratio in women was compared with the odds ratio in men by determining whether the ratio was different from 1. This interaction between sex and treatment effect was checked after adjustment for the main baseline risk factors (age, baseline smoking habits, systolic blood pressure, serum cholesterol level, presence of diabetes, and history of stroke or myocardial infarction) in a multivariate logistic model [19] fitted by outcome. For HDFP [5], we censored data at the date of the end of the trial intervention. Two deaths in the trial by Coope and Warrender [16] that were caused by pulmonary embolism were included with cardiovascular-related mortality in our analysis; one early cancer-related death in this trial was included in the analyses of total mortality because of the intention-to-treat principle. To illustrate the difference in the treatment effect between men and women, we applied two graphical approaches to the second and fourth outcomes (all strokes and all coronary events). First, each trial was represented by sex in a treatment-effect graph [20] in which the x-axis is the risk observed in the control group (Rc) and the y-axis is the risk observed in the treated group (Rt) (Figure 1). The odds ratio line, with a slope equal to the odds ratio and a null intercept, indicates the treatment effect by sex. The principal diagonal of the plane Rt x Rc represents the absence of treatment effect (Rt = Rc; odds ratio, 1). The vertical distance between the odds ratio line and the principal diagonal indicates the absolute risk reduction for a given untreated risk. Second, the absolute risk reduction attributable to treatment and its CI were computed by tertiles of individually predicted risk for each sex and were plotted against the average predicted risk in each tertile (Figure 2). The predicted risk was derived from individual scoring built on the results of a multivariate logistic model, including the major risk factors mentioned above. Tertiles were computed to contain similar numbers of events. Figure 1. Effect of antihypertensive treatment on absolute risk for fatal and nonfatal stroke (left) and fatal and nonfatal coronary events (right). Figure 2. Absolute risk reduction of fatal and nonfatal stroke (left) and fatal and nonfatal coronary events (right) by untreated risk level and sex. Meta-analysis computations were done using Easy-MA software [21]; data management and logistic regression were done using SAS software [22]. Results The key features of the seven trials are presented in Table 1. Five of the trials addressed hypertension in older persons, and two studied mild to moderate hypertension in younger persons. The drugs used in the trials were primarily thiazide diuretics, -blockers, or both. The data for these seven trials contained in the INDANA database represent 97.5% of all existing data from all applicable trials in terms of patient-years of follow-up during the active phase of the trials. The combined trial data on risk factors by sex (Table 2) show that, on average, women were older; had a higher baseline cholesterol level, a higher systolic blood pressure, and a lower smoking rate; and less frequently had a history of myocardial infarction. Because these baseline characteristics were similar for the active treatment and control groups, these groups are combined in Table 2. Table 2. Main Cardiovascular Risk Factors by Sex* For each of the seven outcomes, Table 3 and Table 5 shows the number of events in the active treatment and control groups that occurred in men and women, both within each trial and in all trials combined. Table 3. Events by Trial and Sex* Table 5. Table 3. Continued The exclusion of the HDFP data from the analysis changes neither the direction nor the magnitude of the odds ratio for either sex and does not affect the differences between men and women. These data are therefore included in the results presented. In Table 4, the combined odds ratios for all trials are shown separately for men and women; these odds ratios were estimated using a fixed-effects method. In women, odds ratios favoring treatment were statistically significant for strokes (both fatal and either fatal or nonfatal) and major car


Stroke | 1997

Effect of Antihypertensive Treatment in Patients Having Already Suffered From Stroke: Gathering the Evidence

François Gueyffier; Jean-Pierre Boissel; Florent Boutitie; Stuart J. Pocock; John Coope; Jeffrey A. Cutler; Tord Ekbom; Robert Fagard; Lawrence S. Friedman; Karla Kerlikowske; Mitchell Perry; Ronald J. Prineas; Eleanor Schron

BACKGROUND AND PURPOSE Drug treatment of high blood pressure has been shown to reduce the associated cardiovascular risk. Stroke represents the type of event more strongly linked with high blood pressure, responsible for a high rate of death or invalidity, and with the highest proportion of events that can be avoided by treatment. Hypertensive patients with a history of cerebrovascular accident are at particularly high risk of recurrence. Specific trials of blood pressure lowering drugs in stroke survivors showed inconclusive results in the past. METHODS We performed a meta-analysis using all available randomized controlled clinical trials assessing the effect of blood pressure lowering drugs on clinical outcomes (recurrence of stroke, coronary events, cause-specific, and overall mortality) in patients with prior stroke or transient ischemic attack. RESULTS We identified 9 trials, including a total of 6752 patients: 2 trials included 551 hypertensive stroke survivors; 6 trials of hypertensive patients included a small proportion of stroke survivors (536 patients); 1 trial included stroke survivors, whether hypertensive or not (5665 patients). The recurrence of stroke, fatal and nonfatal, was significantly reduced in active groups compared with control groups consistently across the different sources of data (relative risk of 0.72, 95% confidence interval: 0.61 to 0.85). There was no evidence that this intervention induced serious adverse effect. CONCLUSIONS Blood pressure lowering drug interventions reduced the risk of stroke recurrence in stroke survivors. Available data did not allow to verify whether such benefit depends on initial blood pressure level. More data are needed before considering antihypertensive therapy in normotensive patients at high cerebrovascular risk.


Clinics in Liver Disease | 2002

The liver in heart failure

Cosmas Giallourakis; Peter M Rosenberg; Lawrence S. Friedman

Severe congestive heart failure is associated with two distinct forms of liver dysfunction: jaundice that is related to passive congestion and acute hepatocellular necrosis that is caused by impaired perfusion. Cardiac cirrhosis (fibrosis) may result from prolonged recurrent congestive heart failure. Ischemic hepatitis (shock liver) usually manifests as asymptomatic elevation of the serum aminotransferase levels after an episode of hypotension, although the clinical presentation may mimic that of acute viral hepatitis. In most cases, ischemic hepatitis is of little clinical consequence and is self-limited. Acute liver failure may occur in patients with preexisting cirrhosis, severe chronic heart failure, or sustained hepatic ischemia.


Neurology | 1990

Autonomic function and human immunodeficiency virus infection

Roy Freeman; Mark S. Roberts; Lawrence S. Friedman; Christopher Broadbridge

We compared autonomic function in 26 patients infected by the human immunodeficiency virus (HIV) (18 AIDS and 8 ARC) to 22 controls. A significant decline in autonomic function was present across groups. Autonomic dysfunction correlated strongly with signs of HIV-associated nervous system disease. We observed significant differences across groups in tests of heart rate variation (expiratory-inspiratory ratio, maximum minus minimum heart rate difference, and mean square successive difference), the mean arterial blood pressure fall to tilting, and the blood pressure response to isometric exercise. A trend of declining autonomic function from controls to AIDS was present in the 30:15 ratio, the Valsalva ratio, the systolic blood pressure fall to standing and tilt, and the cold pressor test. We did not observe any correlation between autonomic dysfunction and individual neurologic signs, prior therapeutic agents, and concurrent HIV-associated inflammatory or neoplastic processes. This study provides support for the presence of autonomic dysfunction in association with HIV infection. Autonomie dysfunction occurs more frequently and with greater severity in patients with AIDS; however, it may be present in the early stages of HIV infection and appears to progress during the illness.


Digestive Diseases | 1999

Adenocarcinoma of the Esophagogastric Junction

Timothy D. Jenkins; Lawrence S. Friedman

Adenocarcinoma of the esophagogastric junction (EGJ) has increased rapidly in incidence in the latter half of the twentieth century. The increase in incidence has affected white men between the ages of 40 and 60 disproportionately. Understanding the etiology and improving treatment requires careful classification of EGJ tumors. A recent consensus conference recognized three types of EGJ adenocarcinomas: distal esophageal, cardia, and subcardia gastric. Distal esophageal adenocarcinomas are associated with Barrett’s esophagus. Heilcobacter pylori infection may play a role in some adenocarcinomas of the subcardia, but the association is unproven. Therapy for all types of EGJ tumors is surgical, but multimodal forms of treatment are commonly used because of the advanced stage at which these tumors often present. Several endoscopic options exist for primary therapy of early-stage tumors and for palliation.


The New England Journal of Medicine | 1993

Irritable Bowel Syndrome

Richard B. Lynn; Lawrence S. Friedman

Irritable bowel syndrome is one of a group of disorders that includes chest pain of unexplained origin, nonulcer dyspepsia, and biliary dyskinesia. These chronic disorders are frequently considered...


The New England Journal of Medicine | 1983

Ranitidine: A new H2-receptor antagonist

Jerome B. Zeldis; Lawrence S. Friedman; Kurt J. Isselbacher

OVER the past six years the treatment of peptic-ulcer disease has been dramatically altered by the introduction and use of cimetidine. This substituted imidazole compound is an effective H2-recepto...


Alimentary Pharmacology & Therapeutics | 2005

Review article: the management of lower gastrointestinal bleeding

James J. Farrell; Lawrence S. Friedman

Several recent advances have been made in the evaluation and management of acute lower gastrointestinal bleeding. This review focuses on the management of lower gastrointestinal bleeding, especially acute severe bleeding.

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Mark Feldman

Presbyterian Hospital of Dallas

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Karen Finlay

Hamilton Health Sciences

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Santiago J. Munoz

Monell Chemical Senses Center

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Carol L. Sipan

San Diego State University

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Norma J. Kelley

San Diego State University

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