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G Oster

Publications and source records attributed to G Oster.

At least 19 recordsLinked to original sources
PubMed1992

A model for evaluating the cost-effectiveness of cholesterol-lowering treatment.

We describe and illustrate the use of a generalizable model for evaluating the cost-effectiveness of alternative cholesterol-lowering treatments. We combine standard incidence-based techniques for measuring the cost of illness with logistic risk functions from the Framingham Heart Study to project, for persons with known coronary risk characteristics, the likelihood of developing coronary heart disease (CHD) over a lifetime as well as a number of related outcomes, including the expected loss of years of life due to CHD, the expected lifetime direct and indirect costs of CHD, and the changes in these outcomes that would result from cholesterol-lowering treatment.

Adult↗
PubMed1992

Outcomes of cefazolin versus ceftriaxone therapy in treating lower respiratory tract infections in adults.

OBJECTIVE: To determine whether choice of a first- versus third-generation cephalosporin as initial therapy for lower respiratory tract infections in hospitalized adults affects the course and duration of care, both of which may influence antimicrobial treatment cost. DESIGN: Retrospective analysis of discharge abstracts and hospital pharmacy records. SETTING: Forty-eight US acute-care hospitals. PATIENTS: One thousand ninety-two hospitalized adults (aged > 17 y) with principal diagnoses of lower respiratory tract infections (DRGs 79-80, 89-90). INTERVENTIONS: Cefazolin or ceftriaxone, given as sole antimicrobial therapy for at least one day. MAIN OUTCOME MEASURES: (1) The number of patients who received another parenteral antibiotic anytime prior to hospital discharge; (2) the number of days during which patients received any parenteral antibiotic while in the hospital; and (3) the number of days patients remained hospitalized following the start of antibiotic therapy. RESULTS: Patients treated with cefazolin (n = 763) were more likely to receive another parenteral antibiotic while in the hospital (30.3 vs. 20.7 percent; p < 0.001) and received more total days of therapy (7.2 vs. 6.7 d; p < 0.05) than those treated with ceftriaxone (n = 329). Although the time to hospital discharge did not differ in the full sample (9.2 d for both groups), it was greater among those receiving cefazolin (8.6 vs. 8.0 d; p < 0.05) when patients with lengths of stay exceeding 24 days were excluded from both groups. CONCLUSIONS: In addition to acquisition cost, differences in course and duration of care should be considered when determining the most cost-effective choice for antimicrobial therapy.

Adolescent↗
PubMed1991

[Compensation claim forms in cases of occupational disability].

Confronted with the contents and questions of the Application Forms, presently in use for disability claims, it appears necessary to revise these forms in several details. Rulings by the Supreme Court to be considered and the existing great variety of definitions in the field of private and legal disability insurance--under the aspects of Social Law in general--call for a critical review, especially with regard to the details to be filled in by the police holder in support of his claim. The author is presenting 2 drafts of revised forms (Application Form for Disability Claims/Medical Report in the Case of Disability), which, in his opinion, should meet the requirements more effectively. On the other hand the author does not claim, that the presented drafts be the ultimate version.

Disability Evaluation↗
PubMed1991

Health-related quality of life among patients undergoing percutaneous transluminal coronary angioplasty.

A randomized clinical trial was recently conducted to investigate whether a new antiplatelet agent could prevent restenosis in patients who had undergone percutaneous transluminal coronary artery angioplasty (PTCA). Approximately 1,200 patients were enrolled at 13 separate clinical sites. To assess the impact of this intervention on health-related quality of life, a patient questionnaire for telephone administration was developed. This questionnaire focused attention on several specific dimensions likely to be important in this patient population: physical well-being, perceived health, emotional well-being, home management, work, recreation, and social and sexual functioning. This paper describes the instrument that was used in this trial and reports on its psychometric [corrected] properties based on completed interviews with approximately 500 patients at study entry and 1 month after PTCA.

Activities of Daily Living↗
PubMed1991

Notochord morphogenesis in Xenopus laevis: simulation of cell behavior underlying tissue convergence and extension.

Cell intercalation and cell shape changes drive notochord morphogenesis in the African frog, Xenopus laevis. Experimental observations show that cells elongate mediolaterally and intercalate between one another, causing the notochord to lengthen and narrow. Descriptive observations provide few clues as to the mechanisms that coordinate and drive these cell movements. It is possible that a few rules governing cell behavior could orchestrate the shaping of the entire tissue. We test this hypothesis by constructing a computer model of the tissue to investigate how rules governing cell motility and cell-cell interactions can account for the major features of notochord morphogenesis. These rules are drawn from the literature on in vitro cell studies and experimental observations of notochord cell behavior. The following types of motility rules are investigated: (1) refractory tissue boundaries that inhibit cell motility, (2) statistical persistence of motion, (3) contact inhibition of protrusion between cells, and (4) polarized and nonpolarized protrusive activity. We show that only the combination of refractory boundaries, contact inhibition and polarized protrusive activity reproduces normal notochord development. Guided by these rules, cells spontaneously align into a parallel array of elongating cells. Self alignment optimizes the geometric conditions for polarized protrusive activity by progressively minimizing contact inhibition between cells. Cell polarization, initiated at refractory tissue boundaries, spreads along successive cell rows into the tissue interior as cells restrict and constrain their neighbors' directional bias. The model demonstrates that several experimentally observed intrinsic cell behaviors, operating simultaneously, may underlie the generation of coordinated cell movements within the developing notochord.

Animals↗
PubMed1990

The risks and benefits of an Rx-to-OTC switch. The case of over-the-counter H2-blockers.

In recent years, many new over-the-counter (OTC) medications have resulted from the granting of OTC status by the U.S. Food and Drug Administration to drug entities that previously were available only by prescription (Rx). While the benefits to consumers of Rx-to-OTC switches may be substantial, they also involve some degree of risk, as usage typically expands and physician supervision diminishes. This study explores the potential utility of techniques of decision analysis in evaluating the balance of these benefits and risks. Histamine H2 receptor antagonists (H2-blockers), which are currently available only by prescription, are presented as a case study and were examined to determine how OTC availability of these agents would alter the patterns, effectiveness, and risks of self-treatment for acid-peptic disorders. Currently, about 5.7 million persons experience an episode of dyspepsia during any given quarter, of whom 3.5 million self-medicate with antacids. Study results indicate that OTC availability of H2-blockers would: 1) increase the proportion of persons with dyspepsia who self-medicate from 61.8% currently to 64.1%; 2) increase the proportion of persons who experience complete relief of their symptoms while self-medicating from 37.9% currently to 43.2%; 3) result in 14 additional cases of serious hematologic disorders and an additional 22,000 instances of minor side effects per quarter, but cause the overall rate of side effects among persons who self-medicate to decline; 4) cause an additional 300 persons per quarter with gastric cancer to self-medicate before seeking professional care, but cause no change in the median time between onset of symptoms and the decision to seek such care; and 5) decrease by 277,000 the number of persons per quarter who seek professional care for dyspepsia. On balance, results suggest that OTC H2-blockers may be a relatively safe and effective means of self-care for acid-peptic disorders, and may substantially reduce the number of patient encounters with the medical care system for minor gastrointestinal complaints. This study also illustrates the potential utility of the techniques of decision analysis to the formulation of drug regulatory policy.

Aged↗
PubMed1990

The mechanical basis of cell rearrangement. I. Epithelial morphogenesis during Fundulus epiboly.

Many morphogenetic processes are accomplished by coordinated cell rearrangements. These rearrangements are accompanied by substantial shifts in the neighbor relationships between cells. Here we propose a model for studying morphogenesis in epithelial sheets by directed cell neighbor change. Our model describes cell rearrangements by accounting for the balance of forces between neighboring cells within an epithelium. Cell rearrangement and cell shape changes occur when these forces are not in mechanical equilibrium. We will show that cell rearrangement within the epidermal enveloping layer (EVL) of the teleost fish Fundulus during epiboly can be explained solely in terms of the balance of forces generated among constituent epithelial cells. Within a cell, we account for circumferential elastic forces and the force generated by hydrostatic and osmotic pressure. The model treats epithelial cells as two-dimensional polygons where the mechanical forces are applied to the polygonal nodes. A cell node protrudes or contracts when the nodal forces are not in mechanical equilibrium. In an epithelial sheet, adjacent cells share common boundary nodes; in this way, mechanical force is transmitted from cell to cell, mimicking junctional coupling. These junctional nodes can slide, and nodes may appear or disappear, so that the number of polygonal sides is variable. Computer graphics allows us to compare numerical simulations of the model with time-lapse cinemicroscopy of cell rearrangements in the living embryo, and data obtained from fixed and silver stained embryos. By manipulating the mechanical properties of the model cells we can study the conditions necessary to reproduce normal cell behavior during Fundulus epiboly. We find that simple stress relaxation is sufficient to account for cell rearrangements among interior cells of the EVL when they are isotropically contractile. Experimental observations show that the number of EVL marginal cells continuously decreases throughout epiboly. In order for the simulation to reproduce this behavior, cells at the EVL boundary must generate protrusive forces rather than contractile tension forces. Therefore, the simulation results suggest that the mechanical properties of EVL marginal cells at their leading edge must be quite different from EVL interior cells.

Animals↗
PubMed1990

Benzodiazepine tranquilizers and the risk of accidental injury.

To determine whether benzodiazepine tranquilizers increase the risk of accidental injury requiring medical attention, we used pharmacy claims submitted to a large third-party payer to identify 4,554 persons who had been prescribed these agents and a matched control group of 13,662 persons who had been prescribed drugs other than benzodiazepines. We then used diagnoses recorded on claims submitted by medical care providers to identify all accident-related care received by these persons during three months before their first-observed prescription for a benzodiazepine or nonbenzodiazepine agent, respectively, and six months subsequently. We found accident-related care was more likely among persons who had been prescribed benzodiazepines; among these persons, the probability of an accident-related medical encounter was higher during months in which a prescription for a benzodiazepine had recently been filled compared to other months; and persons who had filled three or more prescriptions for these agents in the six months following initiation of therapy had a significantly higher risk of an accident-related medical event than those who had filled only one such prescription. Approximately two-fold risks of accident-related care were found, after controlling for age, sex, and prior utilization.

Accidents↗
PubMed1989

The economic costs of non-insulin-dependent diabetes mellitus.

Persons with diabetes experience elevated risks of a variety of other illnesses-- including circulatory, visual, neurological, renal, and skin disorders--relative to their nondiabetic peers. Previous estimates of the economic burden of diabetes, however, have not taken full account of this related morbidity and mortality and have therefore understated the cost to the nation due to this disease. Accordingly, we estimated the economic costs of type II, or non-insulin-dependent, diabetes mellitus, reflecting its contribution to the total burden of disease in the United States. In 1986, non-insulin-dependent diabetes mellitus was responsible for $11.6 billion in health care expenditures, including $6.8 billion for diabetic care and $4.8 billion attributable to an excess prevalence of related (principally cardiovascular) conditions. The human toll of non-insulin-dependent diabetes mellitus included 144,000 deaths -- about 6.8% of total US mortality -- and the total disability of 951,000 persons. The total economic burden of non-insulin-dependent diabetes mellitus in 1986, including health care expenditures and productivity forgone due to disability and premature mortality, was $19.8 billion.

Aged↗
PubMed1989

The cost-effectiveness of counseling smokers to quit.

Cigarette smoking is the most important preventable cause of death in the United States. Surveys of patients, however, suggest that many physicians do not routinely counsel smokers to quit. Because physicians may not consider counseling against smoking to be as worthwhile as other medical practices, we examined its cost-effectiveness. We based our estimates of the effectiveness of physician counseling on published reports of randomized trials and our estimates of its cost on average charges for physician office visits. Our results indicate that the cost-effectiveness of brief advice during routine office visits ranges from $705 to $988 per year of life saved for men and from $1204 to $2058 for women. Follow-up visits about smoking appear to be similarly cost-effective. Physician counseling against smoking, therefore, is at least as cost-effective as several other preventive medical practices and should be a routine part of health care for patients who smoke.

Adult↗
PubMed1989

Cimetidine and adverse reactions: a meta-analysis of randomized clinical trials of short-term therapy.

PURPOSE: We pooled data from randomized, double-blind, placebo-controlled trials to determine the frequency of adverse reactions among patients treated with cimetidine for acute acid-peptic disorders. METHODS: Meta-analysis was used to analyze data obtained from a search of English language reports of trials of cimetidine in the ambulatory treatment of acute acid-peptic disorders that were published between January 1982 and April 1987. RESULTS: Of 161 trials of cimetidine that we identified, 84 provided complete reporting of data on adverse reactions and, of these, 24 employed a randomized, double-blind, placebo-controlled design. Across these 24 trials, the overall rate of reported adverse reactions among 622 patients randomly assigned to receive cimetidine was 10.9%; the corresponding rate among 516 patients randomly assigned to receive placebo was 10.1%. This difference was not statistically significant (p greater than 0.10), nor were any significant differences noted in the frequencies of reported central nervous system or gastrointestinal adverse reactions (p greater than 0.10). Rates of adverse reactions also did not differ by dosage or trial duration. The overall rate of adverse reactions reported in the 60 trials that did not utilize a randomized, double-blind, placebo-controlled design was similar to the rate reported in those that did. CONCLUSIONS: Our findings suggest that the frequency of adverse reactions among patients receiving cimetidine for acute acid-peptic disorders is not significantly different from that of patients receiving placebo.

Acute Disease↗
PubMed1989

An assessment of the role of 123I-N-isopropyl-p-iodoamphetamine with single-photon emission computed tomography in the diagnosis of stroke and Alzheimer's disease.

The role of 123I-N-isopropyl-p-iodoamphetamine (123I-IMP), a new agent used in brain imaging with single-photon emission computed tomography (SPECT), has been assessed in the early diagnosis of acute infarctive stroke and Alzheimer's disease (AD). The diagnosis of these conditions in their early stages has remained problematic, principally due to limitations of existing technologies. To more formally assess this new technology, we estimated the sensitivity and specificity of 123I-IMP SPECT scanning in the diagnosis of stroke and AD. We based our assessment on a review of all published studies that reported on 123I-IMP SPECT scans and which included three or more patients. The results from three major studies indicate that 123I-IMP SPECT scanning has a higher sensitivity (92% to 100%) than computerized tomography (55% to 86%) in the early diagnosis of acute cerebral infarction. Preliminary findings from studies using 123I-IMP SPECT in the diagnosis of early AD are promising and show a sensitivity of at least 69%. Furthermore, 123I-IMP SPECT scanning clearly discriminates patients with advanced AD from normals: sensitivity has ranged from 50% to 100%, while specificity has ranged from 97% to 100%. Studies also suggest that it can discriminate AD patients from those with multi-infarct dementia. Our review indicates that 123I-IMP SPECT may have an important future role in the early diagnosis and management of patients with acute infarctive stroke and AD.

Alzheimer Disease↗
PubMed1989

Cell rearrangement and segmentation in Xenopus: direct observation of cultured explants.

We make use of a novel system of explant culture and high resolution video-film recording to analyse for the first time the cell behaviour underlying convergent extension and segmentation in the somitic mesoderm of Xenopus. We find that a sequence of activities sweeps through the somitic mesoderm from anterior to posterior during gastrulation and neurulation, beginning with radial cell intercalation or thinning, continuing with mediolateral intercalation and cell elongation, and culminating in segmentation and somite rotation. Radial intercalation at the posterior tip lengthens the tissue, while mediolateral intercalation farther anterior converges it toward the midline. This extension of the somitic mesoderm helps to elongate the dorsal side of intact neurulae. By separating tissues, we demonstrate that cell rearrangement is independent of the notochord, but radial intercalation - and thus the bulk of extension - requires the presence of an epithelium, either endodermal or ectodermal. Segmentation, on the other hand, can proceed in somitic mesoderm isolated at the end of gastrulation. Finally, we discuss the relationship between cell rearrangement and segmentation.

Animals↗
PubMed1988

Economic aspects of clinical decision making: applications in patient care.

An overview of the techniques of cost-effectiveness analysis as they apply to clinical decision making is presented, and ways that the techniques can assist decision makers in a limited-resource environment are identified. Most applications of cost-effectiveness analysis concern a problem in which a choice must be made between different ways of accomplishing a given clinical goal, such as treating a particular illness. As such, these applications involve comparisons between competing and mutually exclusive strategies and attempt to identify those strategies that provide the greatest benefit for a given set of resource constraints. The need for these analyses continues to increase as a consequence of the growing importance of rate-based and capitated (as opposed to cost-based) methods of paying for patient care. Despite this growing need, most decision makers will not want or be able to conduct such analyses on a regular basis; they may nonetheless benefit from formal studies of clinical problems conducted and reported by others. The validity and quality of these reports, however, need to be carefully assessed before decisions can be based on such information. Properly done, cost-effectiveness analyses can be powerful tools in clinical decision making, particularly as the concern with providing quality care in a cost-constrained environment continues to grow.

Cost-Benefit Analysis↗
PubMed1987

Cost-effectiveness of antihyperlipemic therapy in the prevention of coronary heart disease. The case of cholestyramine.

Using cholestyramine as a model, we considered the cost-effectiveness of antihyperlipemic therapy in the primary prevention of coronary heart disease among men between 35 and 74 years of age with elevated levels of total plasma cholesterol. Our findings indicate that the cost-effectiveness of treatment varies substantially, ranging from about $36,000 to over $1 million per year of life saved. Cost-effectiveness was highest for younger patients, for those with additional coronary risk factors (eg, smoking or hypertension), and for those whose course of therapy is of less-than-lifelong duration. Conversely, it is lowest for older patients, for those with no additional coronary risk factors, and for those who are treated for a lifetime. Our results suggest that pharmacologic therapy may not be cost-effective for all patients with elevated cholesterol levels, especially those over 65 years of age. For many younger patients, however--those with additional coronary risk factors and more severe elevations in cholesterol levels--the cost-effectiveness of therapy may be comparable with other accepted medical practices.

Adult↗