Search PubMed⌕ Search

Biomedical subjects

D B Mark

Publications and source records attributed to D B Mark.

At least 37 records · Page 2Linked to original sources
PubMed2000

Quality of life after coronary revascularization in the United States and Canada.

Cardiac procedures are performed less frequently in Canada than in the United States (US), yet rates of cardiac death and myocardial infarction are similar. We therefore sought to compare long-term symptoms and quality of life in Canadian and American patients undergoing initial coronary revascularization. The 161 patients enrolled in the Bypass Angioplasty Revascularization Investigation at the Montreal Heart Institute were compared with 934 patients enrolled at 7 US sites. Patients' outcomes were documented for 5 years after random assignment to percutaneous transluminal coronary angioplasty or coronary artery bypass graft surgery. Functional status was assessed using the Duke Activity Status Index. Canadian patients were significantly younger and had more angina at study entry. Death and nonfatal myocardial infarction were not significantly different between Canadian and US patients after adjustment for baseline risk. Canadian patients had significantly greater improvements in functional status at 1-year follow-up (Duke Activity Status Index score + 13.5 vs. + 6.0, p = 0.002), but this difference progressively narrowed over 5 years. Angina was equally prevalent in Canadian and US patients at 1 year (16% vs. 19%), but significantly more prevalent in Canadian patients at 5 years (36% vs. 16%, p = 0.001). Repeat revascularization procedures were performed less often over 5 years among Canadian patients (26% vs. 34%, p = 0.08), especially coronary artery bypass graft surgery after initial percutaneous transluminal coronary angioplasty (18% vs. 32%, p = 0.03). These results suggest more anginal symptoms are required in Canada before coronary revascularization, but as a result Canadians receive greater improvements in quality of life after the procedure.

Angina Pectoris↗
PubMed2000

Cost-effectiveness of platelet glycoprotein IIb/IIIa inhibition with eptifibatide in patients with non-ST-elevation acute coronary syndromes.

BACKGROUND: In the PURSUIT trial, eptifibatide significantly reduced the 30-day incidence of death and myocardial infarction relative to placebo in 9461 patients with an acute coronary syndrome (unstable angina or non-Q-wave myocardial infarction). METHODS AND RESULTS: We conducted a 2-part prospective economic substudy of the 3522 US patients enrolled in PURSUIT: (1) an empirical intention-to-treat comparison of medical costs (hospital plus physician) up to 6 months after hospitalization and (2) a lifetime cost-effectiveness analysis. The base-case cost-effectiveness ratio was expressed as the 1996 US dollars required to add 1 life-year with eptifibatide therapy. The 2 treatment arms had equivalent resource consumption and medical costs (exclusive of the cost of the eptifibatide regimen) during the index (enrollment) hospitalization (P=0.78) and up to 6 months afterward (P=0.60). The average wholesale price of the eptifibatide regimen was $1217, but a typical hospital discounted price was $1014. The estimated life expectancy from randomization in the US patients was 15.96 years for eptifibatide and 15.85 years for placebo, an incremental difference of 0.111. The incremental cost-effectiveness ratio for eptifibatide therapy in US PURSUIT patients was $16 491 per year of life saved. This result was robust through a wide range of sensitivity analyses. The cost-utility ratio for eptifibatide (using time trade-off defined utilities) was $19 693 per added quality-adjusted life-year. CONCLUSIONS: Based on the results observed in the US PURSUIT patients, the routine addition of eptifibatide to standard care for non-ST-elevation acute coronary syndrome patients is economically attractive by conventional standards.

Angina, Unstable↗
PubMed2000

Social support and quality of life in patients with coronary artery disease.

The relationship between perceived social support and domain-specific health-related quality of life (HRQOL) was examined in a sample of cardiac catheterization patients after considering age, gender, race, education, and coronary artery disease (CAD) severity. Data was collected on 4,278 cardiac catheterization patients (63% males) and included 1,215 patients with non-significant CAD and 3,063 patients who had significant CAD ( > or = 75% stenosis of at least one major coronary artery). Among the patients with significant CAD, 2,721 were classified as low disease severity and 342 were considered high disease severity. Regression models indicated that a lack of social support was associated with significantly lower levels of HRQOL across all eight SF-36 HRQOL domains after considering disease severity and other demographic factors. The models also indicated that social support and other relevant variables interacted across various HRQOL domains. Physical function and physical role function were lower with age, whereas mental health, emotional role function, and vitality were higher with age. Females reported lower HRQOL than males across all domains. Minority patients reported lower levels of HRQOL than white patients across four domains. Increased disease severity was related to lower levels among four of the eight HRQOL domains. The observed interactions of social support with minority status, disease severity, and education suggest that a subset of individuals may suffer lower levels of HRQOL. These individuals may subsequently require the greatest degree of care and potentially benefit most from intervention.

Adult↗
PubMed2000

Evaluating the potential 'economic attractiveness' of new therapies in patients with non-ST elevation acute coronary syndrome.

OBJECTIVE: To evaluate the relationship between how much a new cardiovascular therapy improves clinical outcomes over current therapies and how much more it can cost while still remaining 'economically attractive'. DESIGN: We developed a decision model to predict the 6-month cumulative cost savings and increased life expectancy that could be associated with new therapies for patients with non-ST elevation acute coronary syndrome. SETTING: This modelling study used outcome and cost data from US sources. METHODS: Event probabilities at 30 days and 6 months were estimated from US patients with non-ST elevation in the Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes (GUSTO) IIb trial; cost estimates were derived from patients enrolled in the Economics and Quality of Life substudy of this trial. Patient life expectancy estimates were calculated using survival estimates for similar patients treated at Duke University Medical Center. RESULTS: We found that new therapies costing up to $US2000 per episode that reduce 6-month mortality by 0.5%, death and nonfatal myocardial infarction (MI) by 1%, or death, nonfatal MI and revascularisation by 3%, may be cost effective by current standards. When new therapies costing up to $US1000 per episode reduce the absolute rate of death, nonfatal MI and revascularisation at 6 months by 6.5% or more, they may be cost saving. CONCLUSION: Our analysis suggests that economic constraints should not inhibit the development of effective new therapies.

Acute Disease↗
PubMed2000

Coronary catherization patient and wife's perceptions of social support: effects due to characteristics of recipient, provider, and their interaction.

This investigation explored relationships between coronary catherization patient and wife's characteristics and their perceptions of social support. Participants were 124 male patients undergoing diagnostic catherization to detect coronary artery disease (CAD) and their wives. Patients and wives' mean ages were fifty-nine and fifty-six years, respectively. While visiting the hospital both patient and wife independently completed a brief questionnaire that assessed psychological and physical health characteristics and perceptions of social support. Congruent with the interdependent and overlapping contexts, and reciprocal relationships assumptions of Revenson's (1994) ecological/contextual framework, results suggested characteristics of patients and wives (e.g., age, mental health, social functioning, hostility, depression, general perceived health) to interactively moderate their perceptions of social support. Overall, perceptions of social support were found to be influenced by characteristics of the perceiver, the support provider, and their interaction. Concerns for supportive and helpful caregiving are discussed.

Adult↗
PubMed2000

Temporal evolution in the management of acute ST elevation myocardial infarction: the seven-year GUSTO experience from canada and the united states. The North American GUSTO-I and GUSTO-III investigators.

BACKGROUND: Temporal changes in baseline characteristics, treatment and clinical outcomes of patients presenting with acute ST elevation myocardial infarction in Canada and the United States have not been examined comprehensively over time. OBJECTIVES: To evaluate baseline characteristics, process of care and clinical outcomes. Also, to explore whether earlier process-of-care differences between Canada and the United States had changed and, if so, whether they influenced clinical outcomes. PATIENTS AND METHODS: A total of 13, 888 American and 3011 Canadian patients enrolled in 184 American and 38 Canadian hospitals that participated in both the Global Utilization of Streptokinase and Tissue Plasminogen Activator (alteplase) for Occluded Coronary Arteries (GUSTO-I) trial (1990 to 1993) and the Global Utilization of Strategies to Open Occluded Coronary Arteries (GUSTO-III) trial (1995 to 1997) were studied. Logistic regression was used to identify significant prognostic factors, to assess illness severity at hospital presentation and to classify trends between Canada and the United States. RESULTS: In both countries, illness severity on admission increased, door-to-needle time for thrombolysis was reduced, intensive care unit stay was shortened and hospital stay decreased from GUSTO-I to GUSTO-III. Whereas the administration of oral nitrates, calcium blockers and beta-blockers at discharge converged over time between countries, the disparity in the use of angiography and revascularization widened; the rise in American revascularization rate was most evident in patients without in-hospital ischemia. The 30-day and one-year mortality rates were comparable and declined nonsignificantly in both countries. CONCLUSIONS: Despite increased illness severity and varying medication and procedure rates, there was no increase over time in 30-day or one-year mortality; this remained comparable between countries throughout the seven-year observation period.

Aged↗
PubMed1999

Outcomes at 1 year and economic implications of platelet glycoprotein IIb/IIIa blockade in patients undergoing coronary stenting: results from a multicentre randomised trial. EPISTENT Investigators. Evaluation of Platelet IIb/IIIa Inhibitor for Stenting.

BACKGROUND: We assessed in a randomised trial the long-term outcomes for potent adjunctive antiplatelet therapy given at the time of coronary stenting. METHODS: In 63 hospitals in the USA and Canada, 2399 patients were randomly assigned stenting with abciximab, stenting with placebo, or balloon angioplasty with abciximab. Standard adjunctive therapy with aspirin, ticlopidine, and heparin was used. The major outcomes of death and myocardial infarction were assessed at 1-year follow-up by intention to treat. We also investigated the 1-year cost-effectiveness of combined stenting and abciximab therapy. FINDINGS: At 1-year follow-up, eight (1.0%) of 794 patients in the stent plus abciximab group had died, compared with 19 (2.4%) of 809 in the stent plus placebo group (hazard ratio 0.43 [95% CI 0.19-0.97], p=0.037). The combined endpoint of death or large myocardial infarction occurred in 42 (5.3%) and 89 (11.0%), respectively (0.46 [0.32-0.67], p<0.001). By multivariate modelling, the factors independently associated with improved survival were assignment to stenting with abciximab (p=0.027) and greater preprocedural stenosis (p=0.002); those associated with worse survival were age greater than 70 years (p<0.001), previous heart failure (p=0.001), diabetes treated with insulin (p=0.02), and postprocedural occlusion (p<0.001). Relative to stenting plus placebo and balloon angioplasty plus abciximab, the incremental 1-year costs of stenting plus abciximab were US$581 and $932. The corresponding cost-effectiveness ratios were US$5291 and $6213 per added life-year. INTERPRETATION: Coronary stenting with abciximab, compared with stenting alone or balloon angioplasty with abciximab, is associated with improved survival and is an economically attractive therapy by conventional standards.

Abciximab↗
PubMed1999

Cost estimates for treatment of cardiac ischemia (from the Asymptomatic Cardiac Ischemia Pilot [ACIP] study).

Costs for management of myocardial ischemia are enormous, yet comparison cost and outcome data for various ischemia treatment strategies from randomized trials are lacking and will require cost and resource utilization data from a large prospective trial. The Asymptomatic Cardiac Ischemia Pilot provided feasibility data for planning such a trial and an opportunity to estimate the long-term costs of different treatment strategies. Economic implications for ischemia management were compared in 558 patients with stable coronary artery disease and myocardial ischemia during both stress testing and daily life. Participants were randomized to 3 different initial treatment strategies and followed for 2 years. Based on cost trends over follow-up, costs for subsequent care were estimated. As expected, due to initial procedural costs, at 3 months, estimated costs for revascularization were approximately 10 times greater than costs for a medical care strategy. Extrapolated costs for anticipated resource consumption for care beyond 2 years, however, were approximately 2 times greater for an initial medical care strategy than for initial revascularization. This was due to increased need for drugs and hospitalizations for both late revascularizations and other ischemia-related events. Estimated costs for anticipated care in the medical strategies reached the anticipated cost of the revascularization strategy within 10 years. Because this cost-equal time period is well within the median life expectancy for such a patient population, these findings could have important public health implications and require testing in a full-scale prognosis trial. We anticipate that over the patients' life expectancy, early revascularization is likely to become either cost-neutral or cost-effective.

Angioplasty, Balloon, Coronary↗
PubMed1999

Effects of stroke on medical resource use and costs in acute myocardial infarction. GUSTO I Investigators. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries Study.

BACKGROUND: Stroke occurs concurrently with myocardial infarction (MI) in approximately 30 000 US patients each year. This number is expected to rise with the increasing use of thrombolytic therapy for MI. However, no data exist for the economic effect of stroke in the setting of acute MI (AMI). The purpose of this prospective study was to assess the effect of stroke on medical resource use and costs in AMI patients in the United States. METHODS AND RESULTS: Medical resource use and cost data were prospectively collected for 2566 randomly selected US GUSTO I patients (from 23 105 patients) and for the 321 US GUSTO I patients who developed non-bypass surgery-related stroke during the baseline hospitalization. Follow-up was for 1 year. All costs are expressed in 1993 US dollars. During the baseline hospitalization, stroke was associated with a reduction in cardiac procedure rates and an increase in length of stay, despite a hospital mortality rate of 37%. Together with stroke-related procedural costs of $2220 per patient, the baseline medical costs increased by 44% ($29 242 versus $20 301, P<0.0001). Follow-up medical costs were substantially higher for stroke survivors ($22 400 versus $5282, P<0.0001), dominated by the cost of institutional care. The main determinant for institutional care was discharge disability status. The cumulative 1-year medical costs for stroke patients were $15 092 higher than for no-stroke patients. Hemorrhagic stroke patients had a much higher hospital mortality rate than non-hemorrhagic stroke patients (53% versus 15%, P<0.001), which was associated with approximately $7200 lower mean baseline hospitalization cost. At discharge, hemorrhagic stroke patients were more likely to be disabled (68% versus 46%, P=0.002). CONCLUSIONS: In this first large prospective economic study of stroke in AMI patients, we found that strokes were associated with a 60% ($15 092) increase in cumulative 1-year medical costs. Baseline hospitalization costs were 44% higher because of longer mean lengths of stay. Stroke type was a key determinant of baseline cost. Follow-up costs were more than quadrupled for stroke survivors because of the need for institutional care. Disability level was the main determinant of institutional care and thus of follow-up costs.

Activities of Daily Living↗
PubMed1999

Clinical correlates of the initial and long-term cost of coronary bypass surgery and coronary angioplasty.

BACKGROUND: Medical costs vary substantially among patients. Understanding the baseline factors that predict subsequent cost may allow better selection of therapy for individual patients. Understanding the postprocedure events that increase cost should help to improve efficiency and effectiveness of coronary revascularization. METHODS: Data on 4-year costs were collected from patients randomly assigned to coronary angioplasty or bypass surgery as part of the BARI (Bypass Angioplasty Revascularization Investigation) trial. Regression models first examined factors known at the time of randomization that prospectively predicted initial procedure cost and long-term cost. Subsequent models tested the value of postrandomization events as explanatory variables for cost. RESULTS: The independent baseline predictors of higher initial percutaneous transluminal coronary angioplasty cost included 3-vessel disease (+12%) and acute presentations (+22%), whereas the independent predictors of higher initial coronary artery bypass grafting cost included the number of comorbid conditions (+5% per condition) and female sex (+7%). The independent baseline predictors of 4-year cost included heart failure (+26%), diabetes (+22%), comorbidity (+10%), and angioplasty assignment in patients with 2-vessel disease (-15%). Postrandomization models showed higher initial and long-term costs were strongly correlated with the number of repeat revascularization procedures (+30% to +128%) and the occurrence of clinical complications (+8% to +131%). CONCLUSIONS: Two-vessel disease identifies patients likely to have lower costs after angioplasty, whereas heart failure, comorbid conditions, and diabetes identify patients likely to accrue higher costs after either angioplasty or bypass surgery. Long-term costs can be potentially reduced by interventions that decrease procedural complications or reduce the need for repeat revascularization.

Aged↗
PubMed1999

Acute and long-term cost implications of coronary stenting.

OBJECTIVES: We compared the acute and one year medical costs and outcomes of coronary stenting with those for balloon angioplasty (percutaneous transluminal coronary angioplasty) in contemporary clinical practice. BACKGROUND: While coronary stent implantation reduces the need for repeat revascularization, it has been associated with significantly higher acute costs compared with coronary angioplasty. METHODS: We studied patients treated at Duke University between September 1995 and June 1996 who received either coronary stent (n = 384) or coronary angioplasty (n = 159) and met eligibility criteria. Detailed cost data were collected initially and up to one year following the procedure. Our primary analyses compared six and 12 month cumulative costs for coronary angioplasty- and stent-treated cohorts. We also compared treatment costs after excluding nontarget vessel interventions; after limiting analysis to those without prior revascularization; and after risk-adjusting cumulative cost estimates. RESULTS: Baseline clinical characteristics were generally similar between the two treatment groups. The mean in-hospital cost for stent patients was $3,268 higher than for those receiving coronary angioplasty ($14,802 vs. $11,534, p < 0.001). However, stent patients were less likely to be rehospitalized (22% vs. 34%, p = 0.002) or to undergo repeat revascularization (9% vs. 26%, p = 0.001) than coronary angioplasty patients within six months of the procedure. As such, mean cumulative costs at 6 months ($19,598 vs. $19,820, p = 0.18) and one year ($22,140 vs. $22,571, p = 0.26) were similar for the two treatments. Adjusting for baseline predictors of cost and selectively examining target vessel revascularization, or those without prior coronary intervention yielded similar conclusions. CONCLUSIONS: In contemporary practice, coronary stenting provides equivalent or better one-year patient outcomes without increasing cumulative health care costs.

Aged↗
PubMed1999

A comparison of U.S. and Canadian cardiac catheterization practices in detecting severe coronary artery disease after myocardial infarction: efficiency, yield and long-term implications.

OBJECTIVES: We sought to compare U.S. and Canada's post-myocardial infarction (MI) cardiac catheterization practices in the detection of severe coronary artery disease (CAD). BACKGROUND: Little is known about the efficiency with which the aggressive post-MI catheterization strategy observed in the U.S. detects severe CAD compared with the more conservative strategy observed in Canada. METHODS: From the U.S. and Canadian patients who had participated in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Arteries trial (n = 22,280, 11.5% Canadian), we examined the frequency of in-hospital cardiac catheterization, the prevalence of severe CAD observed at catheterization (diagnostic efficiency) and the total number of MI patients with severe CAD identified (diagnostic yield). RESULTS: The rate of catheterization in the U.S. was more than 2.5 times that in Canada (71% vs. 27%, respectively, p < 0.001). With identical prevalences of severe CAD at catheterization (17%) in the two countries, the higher frequency of catheterization in the U.S. resulted in the identification of more than two and a half times as many cases of severe CAD compared with Canada (12 severe CAD cases identified per 100 post-MI patients in the U.S., vs. 4.6 per 100 in Canada). If considered in isolation, we estimated that these differences in severe disease detection might effect a small long-term survival advantage in favor of the U.S. strategy (estimated 5.0 lives saved per 1,000 MI patients). CONCLUSIONS: Canada's more restrictive post-MI cardiac catheterization strategy is no more efficient in identifying severe CAD than the aggressive U.S. strategy, and may fail to identify a substantial number of post-MI patients with high risk coronary anatomy. The long-term impact of these differences in practice patterns requires further evaluation.

Canada↗
PubMed1999

Perception of cognitive function in older adults following coronary artery bypass surgery.

This study examined the effects of coronary artery bypass grafting (CABG) on objective and subjective measures of neurocognitive functioning. Participants were 170 older patients (127 men and 43 women; mean age = 61 years) undergoing CABG. Measures of neurocognitive function, depression, anxiety, and perceived cognitive abilities were administered immediately prior to and 6 weeks following surgery. Although objective measures of impaired cognitive performance following CABG were not related to perceived cognitive difficulties, the presence of anxiety and depression was related to the perception of cognitive functioning. Patients who reported high levels of anxiety and depression 6 weeks after surgery perceived themselves as having poorer cognitive function. Interventions designed to reduce emotional distress could improve patient's perceived cognitive abilities following CABG.

Aged↗