Comparing AMI mortality among hospitals in patients 65 years of age and older: evaluating methods of risk adjustment.

BACKGROUND: Interest in the reporting of risk-adjusted outcomes for patients with acute myocardial infarction is growing. A useful risk-adjustment model must balance parsimony and ease of data collection with predictive ability. METHODS AND RESULTS: From our analysis of 82 359 patients >/=65 years of age admitted with acute myocardial infarction to 2401 hospitals, we derived a parsimonious model that predicts 30-day mortality. The model was validated on a similar group of 78 699 patients from 2386 hospitals. Of the 73 candidate predictor variables examined, 7 variables describing patient characteristics on arrival were selected for inclusion in the final model: age, cardiac arrest, anterior or lateral location of myocardial infarction, systolic blood pressure, white blood cell count, serum creatinine, and congestive heart failure. The area under the receiver-operating characteristic curve for the final model was 0.77 in the derivation cohort and 0.77 in the validation cohort. The rankings of hospitals by performance (in deciles) with this model were most similar to a comprehensive 27-variable model based on medical chart review and least similar to models based on administrative billing codes. CONCLUSIONS: A simple 7-variable risk model performs as well as more complex models in comparing hospital outcomes for acute myocardial infarction. Although there is a continuing need to improve methods of risk adjustment, our results provide a basis for hospitals to develop a simple approach to compare outcomes.

Thrombolytic therapy in older patients.

OBJECTIVES: We compared outcomes following thrombolytic therapy and primary angioplasty with no reperfusion therapy in a population-based cohort of older patients presenting with acute myocardial infarction (AMI) and indications for acute reperfusion. BACKGROUND: Evidence supporting the efficacy of acute reperfusion (thrombolytic therapy or primary angioplasty) in the elderly with suspected AMI is not as strong as it is in younger groups. METHODS: From a national cohort of Medicare beneficiaries with AMI, we identified 37,983 patients age 65 or older who presented within 12 h of symptom onset with ST elevation or left bundle branch block. A total of 14,341 (37.8%) received thrombolytic therapy and 1,599 (4.2%) underwent primary angioplasty within 6 h of hospital arrival. RESULTS: After adjustment for demographic, clinical, hospital and physician factors, and co-interventions, thrombolytic therapy was not associated with a better 30-day survival (odds ratio [OR] 1.01; 95% confidence interval [CI]: 0.94 to 1.09) compared with no therapy, whereas primary angioplasty was (OR 0.79; 95% CI: 0.66 to 0.94). At one year, both thrombolytic therapy (OR 0.84; 95% CI: 0.79 to 0.89) and primary angioplasty (OR 0.71; 95% CI: 0.61 to 0.83) were associated with a survival benefit. CONCLUSIONS: In this national sample of older patients, those who received thrombolytic therapy or primary angioplasty had lower mortality at one year compared with those who did not receive a reperfusion strategy. However, only primary angioplasty was associated with better survival at 30 days. Our findings should heighten interest in further investigating the best approach to the treatment of older patients with suspected AMI and ST segment elevation or left bundle branch block.

Beta-blocker therapy for secondary prevention of myocardial infarction in elderly diabetic patients. Results from the National Cooperative Cardiovascular Project.

OBJECTIVES: We sought to determine the use and association with one-year mortality of beta-blocker therapy for the treatment of acute myocardial infarction (AMI) in elderly diabetic patients and to examine whether beta-blocker therapy was associated with increased rates of hospital readmission for diabetic complications traditionally associated with beta-blockers. BACKGROUND: Although many randomized trials have demonstrated that beta-blockers are effective in reducing mortality after AMI, some experts are concerned about the use of beta-blockers in diabetic patients. Little is known about the effectiveness and complication rate of beta-blocker therapy after AMI for elderly diabetics in community practice settings. METHODS: We conducted a retrospective cohort study using the National Cooperative Cardiovascular Project, which contained data abstracted from hospital medical records of Medicare beneficiaries admitted with an AMI during 1994 and 1995. RESULTS: Out of 45,308 patients without contraindications to beta-blocker therapy, 7.4% were insulin-treated diabetics and 18.5% were non-insulin-treated diabetics. Beta-blockers were prescribed at discharge for 45% of insulin-treated diabetics, 48.1% of non-insulin-treated diabetics and 51% of nondiabetics (p < 0.001). After adjusting for demographic and clinical factors, diabetics continued to be less likely to receive beta-blockers at discharge compared with nondiabetics (odds ratio [OR] for insulin-treated diabetics 0.88, 95% confidence interval [CI] 0.82 to 0.96; OR for non-insulin-treated diabetics 0.93, 95% CI 0.88 to 0.98). After adjusting for potential confounders, beta-blockers were associated with lower one-year mortality for insulin-treated diabetics (hazard ratio [HR] = 0.87, 95% CI 0.72 to 1.07), non-insulin-treated diabetics (HR = 0.77, 95% CI 0.67 to 0.88) and nondiabetics (HR = 0.87, 95% CI 0.80 to 0.94). Beta-blocker therapy was not significantly associated with increased six-month readmission rates for diabetic complications among diabetics and nondiabetics. CONCLUSIONS: Beta-blockers are associated with a lower one-year mortality rate for elderly diabetic patients to a similar extent as for nondiabetics, without increased risk of readmission for diabetic complications. Increasing the use of beta-blockers in elderly diabetic patients represents an opportunity to improve the care and outcomes of these patients after AMI.

Acute myocardial infarction in the elderly: differences by age.

OBJECTIVES: We evaluated the clinical characteristics and outcomes of elderly patients hospitalized with acute myocardial infarction (AMI) to describe differences by age. BACKGROUND: Elderly patients with AMI are perceived as a homogeneous population, though the extent by which clinical characteristics vary among elderly patients has not been well described. METHODS: Data from 163,140 hospital admissions of Medicare beneficiaries age > or =65 years between 1994 and 1996 with AMI at U.S. hospitals were evaluated for differences in clinical characteristics and mortality across five age-based strata (in years): 65 to 69, 70 to 74, 75 to 79, 80 to 84 and > or =85. RESULTS: Older age was associated with a greater proportion of patients with functional limitations, heart failure, prior coronary disease and renal insufficiency and a lower proportion of male and diabetic patients. Of note, the proportion of patients presenting with chest pain within 6 h of symptom onset, and with ST-segment elevation, was lower in each successive age group. Thirty-day mortality rates were higher in older age groups (65 to 69: 10.9%, 70 to 74: 14.1%, 75 to 79: 18.5%, 80 to 84: 23.2%, > or =85: 31.2%, p = 0.001 for trend). The effect of age persisted but was attenuated after adjustment for differences in patient characteristics; similar trends were observed for one-year mortality. CONCLUSIONS: Our data indicate significant age-associated differences in clinical characteristics in elderly patients with AMI, which account for some of the age-associated differences in mortality. The practice of grouping older patients together as a single age group may obscure important age-associated differences.

Predicting one-year mortality among elderly survivors of hospitalization for an acute myocardial infarction: results from the Cooperative Cardiovascular Project.

OBJECTIVES: We sought to develop a model based on information available from the medical record that would accurately stratify elderly patients who survive hospitalization with an acute myocardial infarction (AMI) according to their risk of one-year mortality. BACKGROUND: Prediction of the risk of mortality among older survivors of an AMI has many uses, yet few studies have determined the prognostic importance of demographic, clinical and functional data that are available on discharge in a population-based sample. METHODS: In a cohort of patients aged > or = 65 years who survived hospitalization for a confirmed AMI from 1994 to 1995 at acute care, nongovernmental hospitals in the U.S., we developed a parsimonious model to stratify patients by their risk of one-year mortality. RESULTS: The study sample of 103,164 patients, with a mean age of 76.8 years, had a one-year mortality of 22%. The factors with the strongest association with mortality were older age, urinary incontinence, assisted mobility, presence of heart failure or cardiomegaly any time before discharge, presence of peripheral vascular disease, body mass index <20 kg/m2, renal dysfunction (defined as creatinine >2.5 mg/dl or blood urea nitrogen >40 mg/dl) and left ventricular dysfunction (left ventricular ejection fraction <40%). On the basis of the coefficients in the model, patients were stratified into risk groups ranging from 7% to 49%. CONCLUSIONS: We demonstrate that a simple risk model can stratify older patients well by their risk of death one year after discharge for AMI.

The association between white blood cell count and acute myocardial infarction mortality in patients > or =65 years of age: findings from the cooperative cardiovascular project.

OBJECTIVES: The purpose of the study was to examine the association between white blood cell (WBC) count on admission and 30-day mortality in patients with acute myocardial infarction (AMI). BACKGROUND: Elevations in WBC count have been associated with the development of AMI and with long-term mortality in patients with coronary artery disease. However, the relationship between WBC count and prognosis following AMI is less clear. METHODS: Using the Cooperative Cardiovascular Project database, we evaluated 153,213 patients > or = 65 years of age admitted with AMI. RESULTS: An increasing WBC count is associated with a significantly higher risk of in-hospital events, in-hospital mortality and 30-day mortality. Relative to those patients in the lowest quintile, patients in the highest quintile were three times more likely to die at 30 days (10.3% vs. 32.3%; p < 0.001). After adjustment for confounding factors, WBC count was found to be a strong independent predictor of 30-day mortality (odds ratio = 2.37; 95% confidence interval 2.25 to 2.49, p = 0.0001 for the highest quintile of WBC count). CONCLUSIONS: White blood cell count within 24 h of admission for an AMI is a strong and independent predictor of in-hospital and 30-day mortality as well as in-hospital clinical events. Although the mechanism of the association remains speculative, the results of this study have important clinical implications for risk-stratifying patients with AMI.

Effectiveness of beta-blocker therapy after acute myocardial infarction in elderly patients with chronic obstructive pulmonary disease or asthma.

OBJECTIVES: We evaluated the use and effectiveness of beta-blocker therapy after acute myocardial infarction (AMI) for elderly patients with chronic obstructive pulmonary disease (COPD) or asthma. BACKGROUND: Because patients with COPD and asthma have largely been excluded from clinical trials of beta-blocker therapy for AMI, the extent to which these patients would benefit from beta-blocker therapy after AMI is not well defined. METHODS: Using data from the Cooperative Cardiovascular Project, we examined the relationship between discharge use of beta-blockers and one-year mortality in patients with COPD or asthma who were not using beta-agonists, patients with COPD or asthma who were concurrently using beta-agonists and patients with evidence of severe disease (use of prednisone or previous hospitalization for COPD or asthma) compared with patients without COPD or asthma. RESULTS: Of 54,962 patients without contraindications to beta-blockers, patients with COPD or asthma (20%) were significantly less likely to be prescribed beta-blockers at discharge after AMI. After adjusting for demographic and clinical factors, we found that beta-blockers were associated with lower one-year mortality in patients with COPD or asthma who were not on beta-agonist therapy (relative risk [RR] = 0.85, 95% confidence interval [CI] 0.73 to 1.00), similar to patients without COPD or asthma (RR = 0.86, 95% CI 0.81 to 0.92). A survival benefit for beta-blockers was not found among patients concurrently using beta-agonists or with severe COPD or asthma. CONCLUSIONS: Beta-blocker therapy after AMI may be beneficial for COPD or asthma patients with mild disease. A survival benefit was not found for elderly AMI patients with more severe pulmonary disease.

Selective dopamine-1 agonist therapy in severe hypertension: effects of intravenous fenoldopam.

To determine the effects of dopamine-1 agonist therapy in severe hypertension, blood pressure, heart rate, catecholamines and left ventricular function were studied in 18 patients (10 with renal disease) with diastolic blood pressure greater than 120 mm Hg (range 124 to 160) after intravenous fenoldopam therapy. Constant infusions of fenoldopam were titrated upward every 10 to 20 min from an initial dose of 0.1 microgram/kg per min to a maximal dose of 0.9 microgram/kg per min. The therapeutic goal of a supine diastolic blood pressure of less than 110 mm Hg was achieved in every patient within 1 h at an average dose of 0.34 +/- 0.22 microgram/kg per min. Blood pressure decreased from 214/134 +/- 33/10 mm Hg at baseline to 170/96 +/- 29/7 mm Hg (p less than 0.0001) at 3 h, whereas heart rate increased from 77 +/- 23 to 88 +/- 21 beats/min (p less than 0.01). Plasma norepinephrine increased during the fenoldopam infusion; epinephrine and dopamine levels did not change. Two indexes of left ventricular function (end-systolic dimension and isovolumic relaxation time) improved during the fenoldopam infusion, but mitral flow velocities during ventricular filling were unchanged. Side effects of intravenous fenoldopam were mild, transient and associated with the marked vasodilatory properties of the drug. Thus, fenoldopam is safe and effective as a parenteral monotherapy in patients with severe essential and renovascular hypertension. Preliminary data suggest that blood pressure reduction with selective dopamine-1 agonist therapy is accompanied by improved left ventricular function.

Trends in the quality of care for Medicare beneficiaries admitted to the hospital with unstable angina.

OBJECTIVES: We sought to 1) determine the proportion of appropriate elderly patients admitted to the hospital with unstable angina who are treated with aspirin and heparin; 2) identify patient factors associated with the Agency for Health Care Policy and Research (AHCPR) guideline-based use of aspirin and heparin; and 3) compare practice patterns and patient outcomes before and after publication of the AHCPR guidelines. BACKGROUND: Improving the care of patients with unstable angina may provide immediate opportunities to mitigate the adverse consequences of unstable angina. However, despite the importance of this diagnosis, there is a paucity of information on the patterns of treatment and outcomes across diverse sites and recent trends in practice that have occurred, especially since the publication of the AHCPR practice guidelines. METHOD: We performed a retrospective cohort study using data created from medical charts and administrative files. The sample included 300 consecutive patients admitted to one of three Connecticut hospitals in the period 1993 to 1994 and 150 consecutive patients admitted in 1995 with a principal discharge diagnosis of unstable angina or chest pain. RESULTS: Of the 384 patients > or =65 years old who had no contraindications to aspirin on hospital admission, 276 (72%) received it. Of the 369 patients > or =65 years old who had no contraindications to heparin on admission, 88 (24%) received it. Among the 321 patients > or =65 years old who had no contraindications to aspirin at hospital discharge, 208 (65%) were prescribed it. When 1995 was compared with 1993 to 1994, the use of aspirin (odds ratio [OR] 2.3, 95% confidence interval [CI] 1.3 to 4.0) and heparin (OR 2.8, 95% CI 1.6 to 4.9) on hospital admission significantly increased, and the use of aspirin at discharge (OR 1.4, 95% CI 0.8 to 2.4) increased. Concomitantly, there was a significant reduction in 30-day readmission (OR 0.52, 95% CI 0.27 to 0.99). CONCLUSIONS: Our results indicate an improvement in the care and outcomes of elderly patients with unstable angina, but there remain opportunities for further improvement.

Use and effectiveness of intravenous heparin therapy for treatment of acute myocardial infarction in the elderly.

OBJECTIVES: We sought to determine the use and association with 30-day mortality of intravenous heparin for the treatment of acute myocardial infarction in elderly patients not treated with a reperfusion strategy and without contraindications to anticoagulation. BACKGROUND: The benefit of using full-dose intravenous heparin for the treatment of acute myocardial infarction in the elderly is not known. METHODS: We conducted a retrospective cohort study using hospital medical records of all Medicare beneficiaries admitted to the hospital with an acute myocardial infarction in Alabama, Connecticut, Iowa and Wisconsin from June 1992 through February 1993. RESULTS: Among the 6,935 patients > or = 65 years old who had no absolute chart-documented contraindications to heparin, 3,227 (47%) received early full-dose intravenous heparin therapy. After adjustment for baseline differences in demographic, clinical and treatment factors between patients with and without heparin, the use of heparin (odds ratio 1.02, 95% confidence interval 0.87 to 1.18) was not associated with a significantly better 30-day mortality rate. CONCLUSIONS: Although intravenous heparin was commonly used for treatment of acute myocardial infarction in the elderly, it was not associated with an improved 30-day mortality rate. Although the findings of this observational study must be interpreted with care, they lead us to question whether the prevalent use of intravenous heparin has therapeutic effectiveness in this population.

Quality of medical care and excess mortality in older patients with mental disorders.

BACKGROUND: This study investigated whether differences in quality of medical care might explain a portion of the excess mortality associated with mental disorders in the year after myocardial infarction. METHODS: This study examined a national cohort of 88 241 Medicare patients 65 years and older who were hospitalized for clinically confirmed acute myocardial infarction. Proportional hazard models compared the association between mental disorders and mortality before and after adjusting 5 established quality indicators: reperfusion, aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and smoking cessation counseling. All models adjusted for eligibility for each procedure, demographic characteristics, cardiac risk factors and history, admission characteristics, left ventricular function, hospital characteristics, and regional factors. RESULTS: After adjusting for the potential confounding factors, presence of any mental disorder was associated with a 19% increase in 1-year risk of mortality (hazard ratios [HR], 1.19; 95% confidence interval [CI], 1.04-1.36). After adding the 5 quality measures to the model, the association was no longer significant (HR, 1.10; 95% CI, 0.96-1.26). Similarly, while schizophrenia (HR, 1.34; 95% CI, 1.01-1.67) and major affective disorders (HR, 1.11; 95% CI, 1.02-1.20) were each initially associated with increased mortality, after adding the quality variables, neither schizophrenia (HR, 1.23; 95% CI, 0.86-1.60) nor major affective disorder (HR, 1.05; 95% CI, 0.87-1.23) remained a significant predictor. CONCLUSIONS: Deficits in quality of medical care seemed to explain a substantial portion of the excess mortality experienced by patients with mental disorders after myocardial infarction. The study suggests the potential importance of improving these patients' medical care as a step toward reducing their excess mortality.

Aspirin and angiotensin-converting enzyme inhibitors among elderly survivors of hospitalization for an acute myocardial infarction.

BACKGROUND: Aspirin and angiotensin-converting enzyme (ACE) inhibitors are recommended for secondary prevention after acute myocardial infarction (AMI), but several studies have suggested that the combination of these medications may produce a negative interaction. OBJECTIVE: To evaluate the effect and interaction of aspirin and ACE inhibitors on mortality among elderly patients who survived a hospitalization for AMI. METHODS: We evaluated the effect and interaction of aspirin and ACE inhibitors on mortality in patients aged 65 years and older who survived hospitalization with a confirmed AMI who were ideal candidates for the therapies. RESULTS: Among the 14 129 patients, 26% received aspirin only, 20% received ACE inhibitors only, 38% received both, and 16% received neither at discharge. In the multivariate analysis, patients who received both aspirin and ACE inhibitors alone had a significantly lower 1-year mortality (adjusted risk ratio [ARR], 0.86 [95% confidence interval (CI), 0.78-0.95] vs 0.85 [95% CI, 0.77-0.93], respectively) compared with patients who received neither aspirin nor ACE inhibitors at discharge. Prescribing both aspirin and ACE inhibitors was associated with a slightly lower risk of mortality (ARR, 0.81; 95% CI, 0.74-0.88) than that seen in aspirin-only or ACE inhibitor-only groups, but the difference was not significantly different from the use of either medication alone. CONCLUSIONS: The benefit of ACE inhibitors and aspirin is consistent with what would be expected from overall results of randomized trials; prescribed together, the effect is slightly greater than with either one alone, but not significantly or substantially so.

Aspirin and the treatment of heart failure in the elderly.

OBJECTIVES: We sought (1) to determine how often aspirin is prescribed as a discharge medication among patients 65 years or older and hospitalized with both heart failure and coronary artery disease; (2) to identify patient characteristics associated with the decision to prescribe aspirin; and (3) to evaluate the association between aspirin prescription at discharge and 1-year survival. METHODS: We performed a retrospective cohort study of consecutive Medicare beneficiary survivors of a hospitalization for heart failure at 18 Connecticut hospitals (up to 200 hospitalizations per hospital) from 1994 to 1995. RESULTS: Among the 1110 patients in the study sample who did not have a contraindication to aspirin, aspirin therapy was prescribed for 456 (41%) at discharge. Patients who were prescribed aspirin at discharge had a lower 1-year mortality after discharge than patients who were not prescribed aspirin (odds ratio, 0.71; 95% confidence interval, 0.54-0.94), even after adjustment for baseline differences in demographic, clinical, and treatment characteristics between the 2 groups. CONCLUSIONS: This study has identified a strong association between the use of aspirin and lower mortality in older patients with both heart failure and coronary artery disease. The benefit of aspirin is consistent with that expected from randomized trials of other groups of patients with vascular disease.

Quality of care for elderly patients hospitalized with heart failure.

BACKGROUND: There is increasing interest in the development of explicit criteria to evaluate the quality of care for patients with heart failure. However, despite this interest, there is a paucity of information about the care of these patients in actual clinical practice across diverse sites. METHODS: We conducted a retrospective medical record review across 9 acute care hospitals in Connecticut. We selected 200 random admissions from each hospital with a principal discharge diagnosis of heart failure in 1994. Hospitals with fewer than 200 cases had 100% of cases selected. Patients with heart failure secondary to severe aortic stenosis, mitral stenosis, or medical illness were excluded. We evaluated the percentage of patients receiving appropriate treatments and interventions as defined by quality-of-care indicators derived from the Agency for Health Care Policy and Research Clinical Practice Guidelines. RESULTS: Data were abstracted from 1623 hospitalizations and the presence of heart failure was validated by chart review in 1535 (95%). In cohorts of ideal candidates for specific interventions, 832 (75%) of 1110 had a left ventricular ejection fraction documented or measured; 346 (86%) of 401 received angiotensin-converting enzyme inhibitors; 38 (14%) of 271 received target doses of angiotensin-converting enzyme inhibitors; 1359 (97%) of 1400 had counseling about medications documented; 90 (6%) of 1400 had counseling about weight documented; 980 (70%) of 1400 had counseling about diet documented; 856 (61%) of 1400 had counseling about exercise and activity documented; and 14 (11%) of 128 smokers had counseling about cessation documented. CONCLUSIONS: These data demonstrate that the documentation of left ventricular systolic function and counseling for diet, weight, activity, and smoking may provide the best opportunities to improve the hospital care of elderly patients with heart failure. The use of angiotensin-converting enzyme inhibitors in appropriate patients is relatively high, indicating successful translation of trial results into clinical practice at these hospitals.

Are beta-blockers effective in elderly patients who undergo coronary revascularization after acute myocardial infarction?

BACKGROUND: Although randomized clinical trials have demonstrated that beta-blocker therapy is effective in reducing mortality after acute myocardial infarction (AMI), many of these studies excluded patients who undergo coronary revascularization. However, the clinical practice guidelines established by the American College of Cardiology and the American Heart Association recommend that beta-blocker therapy be considered for patients who underwent successful revascularization after AMI. METHODS: Using data from the Cooperative Cardiovascular Project, we compared the initiation of beta-blocker therapy at discharge in patients aged 65 years or older who underwent coronary artery bypass surgery (CABG) or percutaneous transluminal coronary angioplasty (PTCA) during their hospitalization for AMI with that of patients who did not undergo revascularization. We then examined whether beta-blocker therapy was associated with lower 1-year mortality between revascularized and nonrevascularized groups. RESULTS: After excluding patients with contraindications to beta-blocker therapy, 84 457 patients remained in the study sample. Of these, 8482 patients underwent CABG, and 13 997 patients underwent PTCA. After adjusting for demographic and clinical factors, we found that these patients were less likely to initiate beta-blocker therapy after CABG (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.41-0.47) or PTCA (OR, 0.89; 95% CI, 0.85-0.93) relative to the nonrevascularized group. After adjusting for potential confounders, beta-blockers were significantly associated with lower 1-year mortality in patients who underwent CABG (hazard ratio [HR], 0.70; 95% CI, 0.55-0.89) or PTCA (HR, 0.86; 95% CI, 0.74-1.00), similar to that of the non-revascularized group (HR, 0.83; 95% CI, 0.80-0.87). CONCLUSIONS: Therapy after AMI with beta-blockers appears to be as effective in reducing 1-year mortality for elderly patients who have undergone CABG or PTCA as for a nonrevascularized group. Our findings suggest that routine use of beta-blockers should be considered for patients who undergo revascularization after AMI.

Readmission after hospitalization for congestive heart failure among Medicare beneficiaries.

BACKGROUND: Congestive heart failure is the most common discharge diagnosis for Medicare beneficiaries. While several single-center studies have suggested that these patients are particularly vulnerable to readmission, no recent study, to our knowledge, has reported the readmission rates for a large number of elderly patients with congestive heart failure across a diverse spectrum of hospitals. OBJECTIVES: To define the readmission rate for elderly patients discharged after an episode of congestive heart failure. To determine the spectrum of diagnoses that are responsible for readmissions among patients with congestive heart failure. To identify patient and hospital characteristics associated with a higher likelihood of readmission. METHODS: This observational study, using Medicare administrative files, evaluated readmission and death among all survivors of a hospitalization in Connecticut for congestive heart failure from fiscal year 1991 through fiscal year 1994. RESULTS: There were 17448 survivors of a hospitalization for congestive heart failure during the study period. In the 6 months following the index admission, 7596 patients (44%) were readmitted to a hospital at least once. Congestive heart failure was the most frequent reason for readmission among study patients, accounting for 18% of all readmissions. In the multivariable analysis, significant predictors of readmission included male sex (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.05-1.20), at least 1 prior admission within 6 months of the index admission (OR, 1.64; 95% CI, 1.53-1.77), Deyo comorbidity score of more than 1 (OR, 1.56; 95% CI, 1.45-1.68), and length of stay in the index hospitalization of more than 7 days (OR, 1.32; 95% CI, 1.24-1.41). While age was not a significant predictor of readmission, it became significant in a model with the combined outcome of readmission or death as the dependent variable. CONCLUSION: Readmission after a hospitalization for congestive heart failure is common among Medicare beneficiaries, with almost half of the patients readmitted within 6 months. This striking rate of readmission in a common diagnosis demands efforts to further clarify the determinants of readmission and develop strategies to prevent this adverse outcome.

Sex differences in mortality after myocardial infarction: evidence for a sex-age interaction.

BACKGROUND: Studies of sex differences in mortality after myocardial infarction (MI) have shown conflicting results. OBJECTIVES: To test the hypothesis that sex differences in mortality after MI vary according to patients' age, with younger women, but not older women, having a higher mortality compared with men. METHODS: We performed a retrospective cohort study of 1025 consecutive patients who met accepted criteria for MI in 1992 and 1993 in 15 Connecticut hospitals. Data for the study were abstracted from medical records. RESULTS: Women had a 40% higher hospital mortality rate than men. Simple age adjustment eliminated the sex difference in mortality rate (odds ratio, 0.99; 95% confidence interval, 0.66-1.48). However, when the sample was subdivided into 2 age groups, women younger than 75 years showed twice as high a mortality rate as men in the same age group, while among older patients no difference in mortality was found. In multivariate analyses the interaction of sex with age was highly significant, even after adjusting for comorbid conditions, clinical severity, process of care, and hospital characteristics. In the fully adjusted model, this interaction indicated that among patients younger than 75 years women had 49% higher odds of hospital death than men, while in the age group 75 years or older women had 46% lower odds of death compared with men. CONCLUSIONS: A higher mortality of women compared with men after MI is confined to the younger age groups. The sex-age interaction should be considered when examining sex differences in mortality after MI.

Prevalence and quality of warfarin use for patients with atrial fibrillation in the long-term care setting.

BACKGROUND: Evidence-based clinical practice guidelines recommend the use of warfarin sodium for stroke prevention in most patients with atrial fibrillation (AF) who do not have risk factors for hemorrhagic complications, irrespective of age. METHODS: The medical records of all residents of a convenience sample of long-term care facilities in Connecticut (n = 21) were reviewed. The percentages of all patients with AF (AF patients) and ideal candidates for warfarin therapy (ie, AF patients with no risk factors for hemorrhage) who received warfarin were determined; for patients receiving warfarin, the percentage of days spent in the therapeutic range of international normalized ratio (INR) values (2.0-3.0) was also assessed. The relationship between receipt of warfarin and the presence of stroke and bleeding risk factors was assessed in multivariate models. RESULTS: Atrial fibrillation was present in 429 (17%) of the 2587 long-term care residents. Overall, 42% of AF patients were receiving warfarin. However, only 44 (53%) of 83 ideal candidates were receiving this therapy. In residents who received warfarin therapy, the therapeutic range of INR values was maintained only 51% of the time. The odds of receiving warfarin in the study sample decreased with increasing number of risk factors for bleeding and increased (nonsignificant trend) with increasing number of stroke risk factors present. CONCLUSIONS: Atrial fibrillation is very common among residents of long-term care facilities. Even among apparently ideal candidates, warfarin therapy is underused for stroke prevention in patients with AF. Prescribing decisions and monitoring related to warfarin therapy in the long-term care setting warrant improvement.

Effect of aminophylline on coronary reactive and functional hyperaemic response in conscious dogs.

This study was undertaken to determine whether adenosine release from myocardial cells plays a role in coronary reactive and functional vasomotion. Reactive hyperaemic blood flow responses to 10 s complete occlusions and 400 ms diastolic occlusions of the left circumflex coronary artery and to the vasomotor responses to the increased cardiac demand following ventricular extra-activation were examined in a chronic, heart-blocked dog preparation during a control period and following intravenous bolus administration of aminophylline (5 mg X kg-1). Aminophylline administration resulted in a 19% decrease in the blood flow debt repayment ratio of 10 s reactive hyperaemic responses compared with the control period. However, administration of aminophylline had no effect on the coronary vascular response to 400 ms diastolic occlusions or to ventricular extra-activations. These observations indicate that adenosine may play a role in the coronary vascular response to prolonged interventions but that other factors, as yet unidentified, may be implicated in the beat-to-beat regulation of coronary vascular resistance.

Care and outcomes of elderly patients with acute myocardial infarction by physician specialty: the effects of comorbidity and functional limitations.

PURPOSE: Whether patients with acute myocardial infarction who are treated by cardiologists have better outcomes than patients treated by generalist physicians is controversial. Because some of the survival benefit associated with cardiology care may be due to baseline differences in patient characteristics, we evaluated how differences in case-mix of comorbid illness and functional limitations may explain the association between specialty care and survival. MATERIALS AND METHODS: We examined the records of 109,243 Medicare beneficiaries hospitalized for myocardial infarction from 1994 to 1995 from the national Cooperative Cardiovascular Project to evaluate the association of physician specialty with 30-day and 1-year mortality. We assessed the extent to which this relation was mediated by differences in the use of guideline-supported therapies (aspirin, beta-blockers, reperfusion, angiotensin-converting enzyme inhibitors) or differences in the clinical characteristics of the patients. RESULTS: Patients who had board-certified cardiologists as attending physicians had the least number of comorbid conditions, whereas patients who had general practitioners or internal medicine subspecialists as attending physicians usually had the most comorbidities. Cardiologists had the greatest use of most guideline-supported therapies, and general practitioners had the lowest use. After adjustment for severity of myocardial infarction, clinical presentation, and hospital characteristics, patients treated by cardiologists were less likely to die within 1 year (relative risk [RR] = 0.92, 95%, confidence interval [CI]: 0.89 to 0. 95), and patients cared for by other general practitioners were more likely to die within 1 year (RR = 1.09, 95% CI: 1.03 to 1.14), than patients cared for by general internists. After adjusting for additional measures of comorbid illness and functional limitations, the 1-year survival benefit associated with cardiology care was attenuated relative to internists (RR = 0.97, 95% CI: 0.94 to 1.0), and the excess mortality associated with general practitioners decreased (RR = 1.05, 95% CI: 1.00 to 1.11). After further adjustment for the use of guideline-supported therapies, both differences in 1-year survival between patients treated by cardiologists or general practitioners were not significantly different from those of patients treated by internists. CONCLUSION: Studies comparing outcomes by physician specialties that do not adjust adequately for differences in patient characteristics may attribute more benefit than is appropriate to specialists who treat patients who have fewer comorbid conditions. Some of the remaining benefit-at least among patients with myocardial infarction-may be attributable to greater use of recommended therapies.