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In reply In his letter, Forwand requests more information on costs of cardiac care in an American compared with a Canadian institution. We performed an economic analysis but did not present it in the article1because of several limitations inherent to such an analysis. These limitations include incomplete information on all services required for the care of patients with myocardial infarction, lack of itemized cost accounting in Canada, and lack of a common cost unit between the two countries. To answer the letter, we include our calculations, realizing that they exhibit some of these limitations. We used charges obtained from Stanford's (Stanford University, Palo Alto, Calif) accounting department for 1989 to 1990 and applied them to the service volumes in both institutions. Our analysis shows that the average charge per patient for in-hospital treatment of acute myocardial infarction was US $18895 at Stanford and US $14 144 at McGill

Background Exercise treadmill testing (ETT) is frequently performed to screen for coronary artery disease (CAD) in asymptomatic individuals; however, its clinical value is questionable. Methods To evaluate the clinical value of ETT, we examined a cohort of asymptomatic individuals undergoing ETT at the Cleveland Clinic between September 1990 and December 1993. ETT was abnormal if it exhibited any of the following; a 1 mm ST-T elevation or depression, a drop in blood pressure ≥10 mmHg, chest pain or failure to reach a target heart rate. Any CAD was defined by at least 1 coronary segment with ≥50% stenosis. Severe CAD was defined by the following: 1) left main coronary artery with ≥50% stenosis, 2) 3 vessels with ≥70% stenosis or 3) proximal left anterior descending artery and 2 vessels with ≥70% stenosis. Results During this period, 4335 ETT's were performed in individuals with no cardiac symptoms. The average age was 53, 89% were male and 16% had at least one cardiac risk factor. Fifteen percent exhibited an abnormal ETT. Among those with an abnormal ETT, 14% underwent coronary angiography while among those with a negative ETT, 1% underwent angiography. Coronary angiography identified 56% as having any CAD and 15% as having severe CAD. In this asymptomatic population, 228 ETT's and 7 coronary angiograms were performed in order to identify 1 individual with severe CAD. Using Medicare reimbursement of $70 for ETT and $1500 for angiography, the cost of screening per case of severe CAD identified would be $26,460. Based on previously published data on survival with surgical and medical therapy in patients with severe CAD, we estimate a cost of $120,000 to $180,000 per year of life saved with this screening approach. Conclusion This low yield suggests that screening asymptomatic individuals with ETT may be costly and of little clinical value compared to other screening approaches.

Objective. —To determine the prevalence and risk factors for human immunodeficiency virus (HIV) and tuberculosis (TB) infection and investigate the relationship between these two infections in homeless adults. Design. —Cross-sectional study. Setting. —Inner-city shelters and free meal programs. Participants. —A representative sample of 1226 adults (≥18 years) were enrolled from community sites. Main Outcome Measures. —Serum HIV-1 antibody status and tuberculin skin test reactivity. Results. —Human immunodeficiency virus seroprevalence was 8.5% (95% confidence interval [CI], 7.0% to 10.1%) and the prevalence of TB infection was 32% (95% CI, 30% to 37%). Nineteen percent of the HIV-seropositive subjects had positive tuberculin skin tests. Independent risk factors for HIV infection included younger age, black race, male homosexual contact, injection drug use, use of injection drugs in shooting galleries, and selling sex. Tuberculosis infection was associated with the duration of homelessness and living in crowded shelters or single-room-occupancy hotels. Injection drug use, a risk factor for HIV, was also a risk factor for TB, with a particularly strong association in women. No evidence of an association between TB and HIV infection was found, even after accounting for anergy. Conclusions. —The homeless population in the United States should be considered a group at high risk for HIV infection and TB. Given the constellation of risk factors present, the high prevalence of infection, and lack of access to medical services, we anticipate that these communicable diseases in this population will represent a growing public health problem. (JAMA. 1994;272:455-461)

To compare practice patterns and clinical outcomes for a costly yet common condition, acute myocardial infarction.Retrospective cohort study in two university hospitals (Stanford [Calif] University and McGill University, Montreal, Quebec) and a patient survey.All consecutive patients (n = 518) treated for acute myocardial infarction in the coronary care unit of those two hospitals over 2 years.Rates of diagnostic and therapeutic procedures, mortality, reinfarction, and level of functional status (by chart review and patient survey).Demographic and clinical characteristics were similar for the two groups. Noninvasive tests were more common at McGill (exercise tests, 56% vs 20%; tests of left ventricular function, 86% vs 59%; P.0001 for both). In contrast, invasive procedures were more common at Stanford (angiography, 55% vs 34%; angioplasty, 30% vs 13%; and bypass surgery, 10% vs 4%; P.0001). At a median follow-up of 20 months, reinfarction and mortality rates were similar at Stanford and McGill (13% vs 8% and 28% vs 27%, respectively; P.05 for both). In contrast, the angina rate was slightly lower at Stanford (33% vs 40%; P = .15), and the functional status of Stanford patients was better than that of McGill patients (mean Duke Activity Status Index score, 28.8 and 22.9, respectively; P = .006). This functional status difference persisted after adjustment for differences in clinical factors, including coronary revascularization.The aggressive treatment of the American patients with myocardial infarction did not improve reinfarction and mortality rates compared with the conservative treatment of the Canadian patients. The superior functional status of the American patients merits further investigation.

A method is presented for estimating the treatment effect in a meta-analysis when some of the studies are comparative studies, and the rest are noncomparative, historical control studies. A random-effects model is used in which the baseline effect in each study is random, but the treatment effect is constant. With this model the appropriate contribution of the historical studies can be determined. Extensions of the model are developed to accommodate preliminary tests for bias, and for the possibility that the treatment effect is heterogeneous.

IN THIS JOURNAL Hermans et al. [l] have performed a retrospective analysis in order to compare alternative therapeutic approaches to the treatment of acute nonlymphocytic leukemia in young adults. They studied the relative efficacy of bone marrow transplantation (BMT) and conventional chemotherapy for patients in first complete remission, using registry information from the European Cooperative Group for Bone Marrow Transplantation, and data from two trials conducted by the European Organization for Research and Treatment ofcancer as controls. They used disease-free survival (DFS) from complete remission (CR) as the primary endpoint. Their analysis involves an adjustment to correct for the bias that is caused by the fact that many patients who might have received transplants are automatically excluded from the BMT series by virtue of an early relapse prior to transplantation. For this purpose they employed the Mantel-Byar procedure [2]. The analysis demonstrates significant superiority for allogeneic BMT over conventional chemotherapy (P = O.Ol), with the results of autologous BMT lying between those of the other two groups. Further analyses using Cox regression with time-dependent covariates demonstrate that the superiority ofallogeneic BMT over conventional therapy is primarily in longer-term disease-free survival, the short-term results being very similar. Less

Objectives The aim of this study was to determine whether the use of amiodarone in patients with atrial fibrillation (AF) increases the risk of bradyarrhythmia requiring a permanent pacemaker. Background Reports of severe bradyarrhythmia during amiodarone therapy are infrequent and limited to studies assessing the therapy’s use in the management of patients with ventricular arrhythmias. Methods A study cohort of 8,770 patients age ≥65 years with a new diagnosis of AF was identified from a provincewide database of Quebec residents with a myocardial infarction (MI) between 1991 and 1999. Using a nested case-control design, 477 cases of bradyarrhythmia requiring a permanent pacemaker were matched (1:4) to 1,908 controls. Multivariable logistic regression was used to estimate the odds ratio (OR) of pacemaker insertion associated with amiodarone use, controlling for baseline risk factors and exposure to sotalol, Class I antiarrhythmic agents, beta-blockers, calcium channel blockers, and digoxin. Results Amiodarone use was associated with an increased risk of pacemaker insertion (OR: 2.14, 95% confidence interval [CI]: 1.30 to 3.54). This effect was modified by gender, with a greater risk in women versus men (OR: 3.86, 95% CI: 1.70 to 8.75 vs. OR: 1.52, 95% CI: 0.80 to 2.89). Digoxin was the only other medication associated with an increased risk of pacemaker insertion (OR: 1.78, 95% CI: 1.37 to 2.31). Conclusions This study suggests that the use of amiodarone in elderly patients with AF and a previous MI increases the risk of bradyarrhythmia requiring a permanent pacemaker. The finding of an augmented risk of pacemaker insertion in elderly women receiving amiodarone requires further investigation.

The measurement of left ventricular ejection fraction (LVEF) plays a key role in many strategies for managing patients after acute myocardial infarction. We tested the hypothesis that exercise capacity 1 month after myocardial infarction provides additional information in patients with a low LVEF and therefore assists in risk stratification. One hundred fifteen patients, with documented myocardial infarction and LVEF less than 35% by gated radionuclide scan 1 month after acute myocardial infarction, were followed up for 2 months to 7 years. Exercise capacity was estimated from a treadmill test 1 month after infarction. Using the Cox proportional hazards model, exercise capacity was a significant predictor of death or reinfarction. The relative risk of death, based on a comparison between the lowermost quintile (less than 4 METS) and uppermost quintile (greater than 7 METS), was 3.5 (95% confidence interval, 1.1-9.7); the relative risk in the fourth, third, and second quintile was 2.7, 2.1, and 1.6, respectively. In a multivariate analysis, the observed effect of a good exercise capacity was independent of LVEF. These data indicate that in patients with a low LVEF after myocardial infarction, useful prognostic information can be obtained from exercise testing.

To evaluate the effectiveness of practice guidelines for return to work after acute myocardial infarction when disseminated from a university-based setting to a practice-based setting.Randomized clinical trial.A total of 187 patients with uncomplicated acute myocardial infarction.Patients were randomly assigned to the intervention (n = 95) or to usual care (n = 92). The intervention consisted of a treadmill test, a counseling session based on the test results, and a consultation letter from a cardiologist to the primary care physician. Individualized recommendations for the timing of return to work, contained in the consultation letter, were based on the patient's risk for recurrent cardiac events.Questionnaire, chart review, and a phone interview documented the timing of return to work and the rates of cardiac death, coronary angioplasty, coronary artery surgery, and recurrent myocardial infarction.Median intervals between acute myocardial infarction and return to work were similar in both groups (intervention, 54 days; usual care, 67 days; P greater than 0.2). Among patients without myocardial ischemia, however, the interval was shorter in the intervention group than in the usual care group (38 days compared with 65 days, respectively, P = 0.008). Among patients with myocardial ischemia, intervals were similar in both groups (80 days compared with 76 days, respectively, P greater than 0.2).Practice guidelines developed in a university-based setting were not as successful in hastening return to work after uncomplicated acute myocardial infarction when tested in a practice-based setting. Physicians' reluctance to follow guidelines for patients with myocardial ischemia reflected their concern with prognosis even though medical outcome was good.

Background Previous studies have compared the treatment and outcome of patients with acute myocardial infarction (AMI) admitted at sites with and without availability of angiography. Although mortality rates do not differ, it is unknown if quality of life (QOL) and functional status differ. Methods We measured QOL and functional status in patients with AMI treated within Quebec at 5 sites with (n = 253) and 5 sites without (n = 334) angiography. Results At admission, clinical characteristics, complication rates, and baseline measures of QOL and functional status were similar at sites with and without angiography. During hospitalization, patients treated at sites with angiography were more likely to undergo an invasive cardiac procedure than patients admitted at sites without angiography (angiography, 63% vs 26%; percutaneous transluminal coronary angioplasty, 33% vs 13%; and coronary artery bypass graft, 12% vs 5%). At 30 days and 6 months after AMI, QOL was slightly superior at sites with angiography, but by 1 year, most measures of QOL were back to baseline at both types of sites and were similar between the 2 groups. At 6 months, most standard health-related QOL components were similar; only physical and emotional role limitations were higher at sites with angiography. Return to work occurred earlier (at 30 days, 23% vs 12%), and a lower proportion of patients was readmitted for angina (within 1 year after AMI, 12% vs 18%) at sites with angiography. Conclusions In the early post-AMI period, the QOL of patients admitted at sites with angiography was higher than that of patients admitted at sites without angiography. However, by 1 year, the QOL and functional status of patients was similar in both groups. Differences in QOL were greatest when differences in treatment were greatest, lending support to a positive albeit small association between an early invasive approach to post-AMI care and improved QOL.

Previous U.S. studies suggest that the incremental ("marginal") use of the aggressive approach to care for acute myocardial infarction (AMI) in patients differing only in their distance to hospitals offering aggressive care may be associated with small mortality benefits. We hypothesized that the marginal benefits should be larger in Canada, as the country is operating on a lower margin because the approach to care is more conservative overall.This retrospective study used administrative data of hospital admissions and health services for all patients admitted for a first AMI in Quebec in 1988 (n = 8,674). We used differential distances to hospitals offering aggressive care as instrumental variables when measuring mortality up to four years after AMI.Of the 4,422 subjects who wereor = 65 years old, 11 percent received cardiac catheterization within 90 days after admission. In a previous study that applied similar methodology to the 1987 U.S. Medicare population, 23 percent of subjects received catheterization within 90 days. As in the U.S. study, we found that subjects living closer to hospitals offering aggressive care were more likely to receive aggressive care than subjects living further away (26 percent versus 19 percent received cardiac catheterization within 90 days; 95 percent CI: 5 percent to 9 percent). Unlike the U.S. study, we found no differences in mortality across the "close" versus "far" differential distance groups (unadjusted differences at one year: 1 percent; 95 percent CI: -1 percent to 3 percent). This absence of association held in elderly (or = 65 years) and younger age groups. Adjusted results also showed no differences between subjects receiving aggressive versus conservative care (at one year: 4 percent; 95 percent CI: -11 percent to 20 percent).Contrary to our hypothesis, but consistent with results from numerous randomized trials and observational studies, we cannot confirm that, on the margin, the aggressive approach to post-AMI care is associated with mortality benefits in Canada.

Warfarin is an effective agent in the prevention of stroke in patients with atrial fibrillation (AF), yet it requires close monitoring. Rural patients often have decreased access to health care, and may be good candidates for new oral anticoagulants that require less monitoring. However, it is

Previous trials examining the use of bupropion as a smoking cessation therapy in post-acute myocardial infarction (AMI) patients have been inconclusive. These findings may be explained, in part, by adherence to study medication. We used data from a placebo-controlled, randomized trial of bupropion

Acute coronary syndrome (ACS) in premenopausal women (PW) is a rare occurrence and limited data is available regarding their risk factors (RF) and angiographic characteristics. GENESIS PRAXY is an international registry of ACS patients younger than 55 years of age across 26 centres. Clinical