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T F Imperiale

Publications and source records attributed to T F Imperiale.

36 records · Page 2Linked to original sources

Primary prophylaxis of variceal bleeding in cirrhosis: a cost-effectiveness analysis.

BACKGROUND & AIMS: Prophylaxis against the first variceal bleeding has been proposed to reduce morbidity and mortality in cirrhotic patients. No previous information is available regarding the cost-effectiveness of prophylaxis. The aim of this study was to compare the cost-effectiveness of variceal bleeding prophylaxis with propranolol, sclerotherapy, and shunt surgery in cirrhotic patients stratified by bleeding risk. METHODS: A hypothetical cohort was stratified according to bleeding risk. The natural history of cirrhosis with esophageal varices was simulated using a Markov model. Transitional probabilities extracted from published studies and costs were obtained from our institution's billing department. Sensitivity analyses were performed for important variables. RESULTS: Propranolol results in cost savings ranging between $450 and $14,600 over a 5-year period. The extent of cost savings depended on the individual patient's bleeding risk. In addition, propranolol increased the quality-adjusted life expectancy by 0.1-0.4 years. Sclerotherapy was significantly less cost-effective than propranolol and had no advantage on quality of life. Shunt surgery was effective therapy for prevention of bleeding but decreased life expectancy and quality of life in some risk groups and was not cost-effective. CONCLUSIONS: Propranolol is the only cost-effective form of prophylactic therapy for preventing initial variceal bleeding in cirrhosis regardless of bleeding risk.

Cost-Benefit Analysis↗

A cost analysis of alternative treatments for duodenal ulcer.

OBJECTIVE: To compare the costs of alternative strategies for the treatment of duodenal ulcer. DESIGN: A cost comparison using decision analysis. METHODS: A decision model was used to compare the costs per cure of an endoscopically documented duodenal ulcer for three initial treatment strategies: 1) H2-receptor antagonist therapy for 8 weeks, 2) antibiotic therapy for Helicobacter pylori infection plus H2-receptor antagonist therapy, and 3) urease test-based treatment. For symptomatic recurrences, secondary treatment strategies included empiric retreatment with the same or other regimen, and treatment based on repeat endoscopy-guided urease test or biopsy, with an assumption of subsequent cure. The cohort modeled for this analysis consisted of patients at low risk for a malignant ulcer. Probability estimates were derived from published clinical trials, cohort studies, and expert opinion. Side effects from combination therapy with antibiotics and H2-receptor antagonists and resulting costs were included from the perspective of a group practice model health maintenance organization. RESULTS: For all secondary treatment strategies, initial therapy with antibiotics for H. pylori infection plus an H2-receptor antagonist resulted in the lowest average costs per symptomatic cure when the prevalence or likelihood of H. pylori infection exceeded 66% to 76%; the costs ranged from $284 for secondary (re)treatment with empiric antibiotic and H2-receptor antagonist therapy to $398 for endoscopy-guided secondary treatment. Initial treatment with an H2-receptor antagonist resulted in the highest costs, ranging from $372 for secondary treatment with empiric antibiotic and H2-receptor antagonist therapy to $679 for endoscopy-guided secondary treatment. The results were not sensitive to the rates of duodenal ulcer recurrence after either treatment, to the cost of either treatment, or to prevalence of H. pylori. CONCLUSIONS: This cost analysis indicates that, regardless of the secondary treatment used for ulcer recurrence, initial therapy with antibiotics for H. pylori infection plus an H2-receptor antagonist provides the lowest costs per symptomatic cure. These cost savings and the lower recurrence rates associated with this treatment favor eradication of H. pylori as part of the initial treatment of duodenal ulcer.

Anti-Bacterial Agents↗

A meta-analysis of somatostatin versus vasopressin in the management of acute esophageal variceal hemorrhage.

BACKGROUND & AIMS: Although sclerotherapy is the current standard therapy for bleeding esophageal varices, the best method for initial control is unclear. The aim of this meta-analysis was to compare the efficacy and toxicity of somatostatin and vasopressin in short-term treatment of hemorrhage from esophageal varices. METHODS: Using MEDLINE, all randomized trials comparing somatostatin with vasopressin in subjects with endoscopically documented acute esophageal variceal bleeding were identified. The quality of each study was critically and independently evaluated, and quantitative data for initial cessation of bleeding, sustained control of bleeding, and major adverse effects were abstracted. The relative risk (RR) and number needed to be treated were calculated. RESULTS: The RR or likelihood of achieving initial control of bleeding with somatostatin vs. vasopressin was 1.62 (95% confidence interval [CI], 1.37-1.93), and the number needed to be treated was 3.7, i.e., between 3 and 4 patients would have to be treated with somatostatin for 1 patient to derive additional benefit over vasopressin. For trials that measured sustained control of bleeding, somatostatin was superior to vasopressin (RR, 1.28 [95% CI, 1.00-1.65]; number needed to be treated, 8.8). The risk of adverse effects was greater for subjects given vasopressin (10% vs. 0%; P = 0.00007). CONCLUSIONS: This meta-analysis suggests that somatostatin is more efficacious in controlling acute hemorrhage from esophageal varices and has a lower risk of adverse effects than vasopressin.

Acute Disease↗

Are cytotoxic agents beneficial in idiopathic membranous nephropathy? A meta-analysis of the controlled trials.

The use of cytotoxic agents for the treatment of idiopathic membranous nephropathy is controversial. Although several controlled trials have been published, both the comparison groups and the study findings have varied, resulting in clinical uncertainty. To explore this uncertainty, a meta-analysis of controlled trials of treatment with cyclophosphamide or chlorambucil was performed in patients with idiopathic membranous nephropathy and nephrotic-range proteinuria. Patients in the control groups received only symptomatic treatment or corticosteroids. Descriptive and quantitative data from each trial were abstracted independently. Outcomes included effects of treatment on renal function and proteinuria, with a complete remission (CR) or partial remission (PR) defined as the complete or partial resolution of proteinuria without deterioration of renal function. For patients having either any response (CR or PR) or only a CR, both the relative risk (RR) and the number needed to be treated were calculated. The five trials that satisfied criteria for inclusion in the analysis were clinically and statistically homogeneous. There were no placebo-controlled trials that met the criteria for inclusion. Among the 228 patients in these studies, the RR of achieving any response with cytotoxic agents was 2.3 (95% confidence interval, 1.7 to 3.2) and the RR for a CR was 4.6 (95% confidence interval, 2.2 to 9.3), with respective numbers needed to be treated of 2.9 and 4.7, meaning that between three and five patients would need to be treated with cytotoxic agents to achieve one response. Exclusion of the only nonrandomized trial had no significant effect on the results. Both chlorambucil and cyclophosphamide showed similar beneficial effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Chlorambucil↗

A meta-analysis of methods to prevent venous thromboembolism following total hip replacement.

OBJECTIVE: While several methods of prophylaxis have been shown to reduce the risk of venous thromboembolism following total hip replacement, the safest and most effective agent is unclear. To clarify this issue, we performed a meta-analysis of the randomized trials of methods used to prevent venous thromboembolism following total hip replacement. DATA SOURCE: English-language human studies articles from 1966 through 1993 were obtained from a MEDLINE database search with indexing terms including thromboembolism, hip replacement or hip prosthesis, and randomized controlled trials. Additional references were obtained from study bibliographies. STUDY SELECTION: The following criteria were used to select studies for inclusion: study design--randomized clinical trial; study population--patients undergoing elective total hip replacement; interventions--aspirin, warfarin, dextran, heparin, low-molecular-weight heparin, compression stockings; and outcomes--venous thromboembolism, major hemorrhage. DATA EXTRACTION: Methodological and descriptive data from each study were abstracted by one author who was blinded to quantitative outcomes data. DATA SYNTHESIS: Ninety-one treatment groups and 25 control groups were identified from 56 trials. Four treatment groups were excluded because of rarely used combinations. Trial populations were clinically homogeneous. When compared with the control arm, all treatments except aspirin reduced the risk of all deep venous thromboses (risk differences range, 0.18 to 0.31; all P values < .05). All treatments except aspirin reduced the risk of proximal venous thrombosis (risk differences range, 0.09 to 0.18; all P values < .05). Only low-molecular-weight heparin and stockings reduced the risk of pulmonary embolism, both with risk differences equal to 0.02. The crude risks of clinically important bleeding as defined by the individual trials were 0% for stockings, 0.3% for controls, and 1.8% for low-molecular-weight heparin. CONCLUSIONS: The results suggest that low-molecular-weight heparin and compression stockings have the greatest relative efficacy in preventing venous thromboembolism following total hip replacement. Low-molecular-weight heparin may be more effective, though at a small risk of clinically important bleeding.

Aspirin↗

Use of the alveolar-arterial oxygen gradient in the diagnosis of pulmonary embolism.

BACKGROUND: Arterial blood gas (ABG) values and the alveolar-arterial oxygen (A-a) gradient are sensitive indicators of pulmonary pathology. Alone, they are not diagnostic of pulmonary embolism (PE), but they may be useful in excluding the diagnosis of PE if their values fall within the normal range. The purpose of this study was to determine the diagnostic value of a normal A-a gradient in ruling out PE. PATIENTS AND METHODS: The Derivation Set came from the records of all patients at Cleveland MetroHealth Medical Center who received a ventilation/perfusion (V/Q) scan for suspected PE in 1988 or 1989. Demographic and clinical data were obtained that included risk factors, symptoms, signs, and laboratory tests. A-a gradients were calculated using a standard equation; a normal gradient was defined as less than or equal to (age/4 + 4). The A-a gradient was examined before and after controlling for PE risk factors. The Validation Set was comprised of patients who had V/Q scans in 1987 and 1990. RESULTS: Among the 873 patients in the Derivation Set, 540 had simultaneous room air ABG determinations. Of these patients, 109 (20%) had a discharge diagnosis of PE. Only 1 of 57 (1.8%; 95% confidence interval [CI]: 0.9%-10.7%) patients without a history of PE or deep venous thrombosis (DVT) and with a normal A-a gradient had PE. Among the 805 V/Q patients in the Validation Set, 489 had simultaneous room air/ABG determinations. Of these, 75 (15%) had PE. Only 1 of 54 (1.9%; 95% CI: 0.1%-11.2%) patients without a history of PE or DVT and with a normal A-a gradient had PE. CONCLUSIONS: A normal A-a gradient among patients without a history of PE or DVT makes the diagnosis of PE unlikely. Further diagnostic evaluation may be unnecessary in this subgroup of patients.

Adult↗

An overview of the efficacy and safety of fenfluramine and mazindol in the treatment of obesity.

OBJECTIVE: To assess the validity of the perceptions that appetite-suppressant drugs are ineffective, potentially addictive, and fraught with side effects, we reviewed the effectiveness and safety of two such drugs with purported low abuse potential in the treatment of obesity: mazindol and fenfluramine hydrochloride. DATA SOURCES: Relevant studies in English published before September 1991 were identified using MEDLINE, accompanied by a cross-referenced manual search. STUDY SELECTION: All randomized clinical trials conducted with adults for at least 6 weeks' duration with weight change as an outcome. DATA EXTRACTION: Data extracted from each report included key study characteristics, clinical information, co-interventions, and outcomes, including dropouts due to either adverse drug effects or perceived lack of effect. DATA SYNTHESIS: Of 36 acceptable trials, 35 were double-blinded, 32 were placebo-controlled, and 13 were cross-over. Median duration of drug therapy was 12 weeks. In studies reporting such data, mean patient age was 41 years, and mean baseline weight was 84 kg (143% of ideal body weight). Among 1163 patients receiving drug therapy and 866 patients receiving placebo, mean weight loss across all trials was 5.2 and 1.9 kg, respectively (P < .001). Among 32 direct comparisons between drug and placebo, the mean weight loss by sample size was 3.0 kg greater in the treatment group (P < .001), and did not vary in subgroup analyses of trial type, drug, or dose. Similar proportions of treatment and placebo groups dropped out (20% vs 22%; P = .34); however, overall dropout rates were higher in parallel trials (25% vs 9% for crossover trials). Dropouts due to adverse drug effects were more common in the treatment group (7% vs 2%; P < .001), while those due to perceived lack of effect were more common in the placebo group (6% vs 2%; P < .001). Mazindol resulted in fewer dropouts due to adverse drug effects (4% vs 9%; P < .001) and a perceived lack of effect (1% v 3%; P = .04). No drug addiction or adverse drug effects requiring medical intervention were reported. CONCLUSION: The apparent short-term efficacy of these appetite-suppressant drugs and the lack of severe adverse drug effects or addiction suggest that they may be useful in the treatment of obesity. Further study of these agents with attention to long-term efficacy, safety, and health consequences is warranted.

Adult↗

A meta-analysis of low-dose aspirin for the prevention of pregnancy-induced hypertensive disease.

BACKGROUND: --Pregnancy-induced hypertension (PIH), defined as either isolated hypertension after the 20th week of gestation or hypertension with proteinuria (preeclampsia), occurs in 5% to 15% of pregnancies and is associated with maternal and neonatal morbidity. Previous clinical trials with small numbers of patients have suggested that aspirin in doses of 60 to 150 mg/d during the second and third trimesters reduces the risk of PIH and improves maternal and neonatal outcomes. OBJECTIVE: --We performed a meta-analysis of the six published controlled trials to estimate more precisely (1) the magnitude of protection of aspirin from PIH; (2) the effect of aspirin on severe low-birth-weight infants, cesarean section, and perinatal mortality; and (3) the risk of adverse effects. METHODS: --We critically and independently evaluated study methods, assigned a quality score to each trial, and abstracted quantitative outcomes data. For each outcome, both relative risk (RR) and the number needed to be treated were calculated. RESULTS: --Among 394 subjects from six trials, the RR of PIH among women who took aspirin was 0.35 (95% confidence interval [CI], 0.22 to 0.55) and the number needed to be treated was 4.4, meaning that between four and five high-risk women would need to be treated with aspirin to prevent one case of PIH. Aspirin reduced the risk of severe low birth weight among newborns by 44% (RR = 0.56; 95% CI, 0.36 to 0.88) and reduced the risk of cesarean section by 66% overall (RR = 0.34; 95% CI, 0.25 to 0.48), although the specific indications for cesarean section were generally not described. There was no effect on fetal and neonatal death (RR = 0.88; 95% CI, 0.32 to 2.46), and there were no maternal or neonatal adverse effects associated with taking aspirin. CONCLUSION: --This meta-analysis suggests that low-dose aspirin reduces the risks of PIH and severe low birth weight, with no observed risk of maternal or neonatal adverse effects.

Aspirin↗

Do corticosteroids reduce mortality from alcoholic hepatitis? A meta-analysis of the randomized trials.

PURPOSE: To determine whether corticosteroids affect short-term mortality from alcoholic hepatitis. DATA IDENTIFICATION: Studies published from 1966 to 1989 were identified through a MEDLINE computer search and an extensive manual search of the bibliographies of identified articles. STUDY SELECTION: We found 11 randomized studies (10 of which were placebo controlled) that assessed mortality in hospitalized patients diagnosed with acute alcoholic hepatitis and treated with corticosteroids. DATA EXTRACTION: Two critical appraisers independently evaluated trial quality and abstracted quantitative data on clinical characteristics of the populations, interventions, and all-cause mortality. RESULTS OF DATA SYNTHESIS: Overall, the protective efficacy (or percent reduction in mortality) of corticosteroids was 37% (95% CI, 20% to 50%). Protective efficacy was higher among trials with higher quality scores and trials that excluded subjects with active gastrointestinal bleeding. In subjects with hepatic encephalopathy, protective efficacy was 34% overall (CI, 15% to 48%). It was also higher among trials with higher quality scores and trials excluding subjects with acute gastrointestinal bleeding, but was not present among trials with lower quality scores or trials that did not exclude subjects with acute gastrointestinal bleeding. In subjects without hepatic encephalopathy, corticosteroids had no protective effect, and this lack of efficacy was consistent across all trial subgroups. CONCLUSIONS: These results suggest that corticosteroids reduce short-term mortality in patients with acute alcoholic hepatitis who have hepatic encephalopathy, that the protective effect depends on the exclusion criterion of acute gastrointestinal bleeding and is influenced by trial quality, and that corticosteroids are of no benefit in patients without hepatic encephalopathy.

Acute Disease↗

Does prophylaxis prevent postdental infective endocarditis? A controlled evaluation of protective efficacy.

PURPOSE: Despite the American Heart Association's (AHA) recommendations for antibiotic prophylaxis to prevent infective endocarditis, no controlled clinical evidence exists for the effectiveness of this intervention. The purpose of this case-control study was to determine whether antibiotic prophylaxis for a dental procedure reduces the risk of infective endocarditis in persons with high-risk cardiac lesions. PATIENTS AND METHODS: Cases consisted of eight subjects with high-risk lesions (six mitral, one aortic, one uncorrected tetralogy) whose first-time, native-valve infective endocarditis occurred within 12 weeks of a dental procedure and was diagnosed between 1980 and 1986. For each case subject, three control subjects were chosen from patients who underwent echocardiographic evaluation between 1980 and 1986, and who were matched for the specific high-risk lesion and age. Use of antibiotic prophylaxis, which was determined by interviews with patients and supplemented by the dentists, was defined as antibiotic taken both before and after the dental procedure. RESULTS: Antibiotic prophylaxis was used by only one of eight (13%) case subjects compared with 15 of 24 (63%) control subjects, for an odds ratio of 0.09, which is clinically impressive (indicating 91% protective efficacy) and statistically significant (p = 0.025). CONCLUSION: Although this report does not specifically assess the value of antibiotic prophylaxis for the current AHA recommendations, the use of antibiotic prophylaxis in persons with high-risk cardiac lesions is supported by the magnitude of protective efficacy observed in this study.

Adult↗

Scientific standards and the design of case-control research.

A new controversy has emerged over the results of a case-control study alleging a causal relationship between certain non-steroidal anti-inflammatory agents (NSAIAs) and the risks of agranulocytosis and aplastic anemia. After describing the methods and results of the International Agranulocytosis and Aplastic Anemia (IAAA) study, we review the distinctive methodologic challenges of this study and the requirements for avoiding bias, and then reconcile the study results with the principles of case-control design. As a result of our analysis, we believe that the IAAA study's most important and reliable finding is its documentation of the infrequent occurrences of aplastic anemia and agranulocytosis with analgesic use. In contrast, a causal association between NSAIAs and blood dyscrasias has not been suitably established, and may well have resulted from several distinctive sources of bias. These include the effects of diagnostic-suspicion bias in case determination, of exclusion bias in choosing controls, of recall bias in determining exposure, and of publicity bias in both case selection and ascertainment of exposure. These problems could have been avoided and a more valid result obtained with closer attention to the experimental paradigm for case-control research.

Agranulocytosis↗

Preadmission screening of Medicare patients. The clinical impact of reimbursement disapproval.

The clinical impact of a statewide Medicare preadmission certification program was assessed with a retrospective survey of Connecticut physicians. In a three-month period, only 100 (0.37%) of 28,450 Medicare admission requests were disapproved for reimbursement. Following disapproval, 22 patients were admitted immediately, 44 received outpatient care, and eight additional outpatients were not evaluated or treated. The remaining 26 patients subsequently were admitted with preadmission approval due to changed clinical condition or failed outpatient plan. Although some patients had minor problems that their physicians believed would have been avoided by immediate admission, no severe morbidity resulted from admission delay. Many physicians expressed concern about preadmission certification program-related patient anxiety and inconvenience. Although this limited survey provides preliminary evidence that preadmission certification programs can be implemented without major deleterious short-term medical effects, continued monitoring of physicians and patients involved in disapproved admissions is necessary to evaluate potential medical and psychosocial problems.

Adult↗

Aortic stenosis, idiopathic gastrointestinal bleeding, and angiodysplasia: is there an association? A methodologic critique of the literature.

To assess the reported association between colonic angiodysplasia and aortic stenosis, we performed a quantitative and methodologic analysis of the literature. In four controlled studies that support an association between aortic stenosis and idiopathic gastrointestinal bleeding there are major methodologic deficiencies including the following: nonblinded data collection, noncomparable diagnostic examination, nonblinded ascertainment of exposure, and noncomparable demographic susceptibility. None of the studies directly assesses angiodysplasia. Additional case reports about aortic valve replacement used to treat bleeding from angiodysplasia are limited in number and in duration of follow-up. We conclude that the existing literature does not demonstrate an association between aortic stenosis and angiodysplasia. Further controlled evaluation of this topic would be useful.

Aortic Valve Stenosis↗

The acute effect of phenylpropanolamine and brompheniramine on blood pressure in controlled hypertension: a randomized double-blind crossover trial.

STUDY OBJECTIVE: To determine the acute effect of phenylpropanolamine, 75 mg, and brompheniramine, 12 mg, in combination (PPA/B) on blood pressure in patients with controlled hypertension, using ambulatory blood pressure monitoring (ABPM). DESIGN: Randomized double-blind crossover trial. SETTING: Outpatient clinic at one medical center. PARTICIPANTS: 13 healthy volunteers aged 36 to 64 years, receiving medication for hypertension. INTERVENTIONS: Following 24-hour baseline ABPM, participants were randomized to receive either placebo or PPA/B every 12 hours for three doses, while ABPM continued. After a 24-hour washout period, all participants received the crossover regimen. MEASUREMENTS AND MAIN RESULTS: No clinically important or statistically significant difference was noted for mean systolic and diastolic blood pressures during the baseline (125/75), PPA/B (127/72), and placebo (126/73) phases of the study. Within the first four hours of treatment, the mean change in systolic blood pressure from baseline between PPA/B and placebo phases was 1.7 mm Hg (95% CI -5.3 to 8.7), and mean change in diastolic blood pressure was 0.9 mm Hg (95% CI -1.6 to 3.5), excluding a first-dose pressor effect. CONCLUSION: When used as recommended, PPA/B, a commonly used over-the-counter cold medication, has no significant acute effect on blood pressure in patients with controlled hypertension.

Blood Pressure↗