Age-related differences in the utilization of therapies post acute myocardial infarction

Beta-blocker underuse in secondary prevention of myocardial infarction

OBJECTIVE

To review the clinical benefits of beta-blockers as secondary prevention following a myocardial infarction (MI) and to address the reasons that clinicians are reluctant to use beta-blockers in specific patient populations.

DATA SOURCES

MEDLINE was searched for articles published from January 1966 to October 2002. Relevant studies were identified by systematic searches of the literature for all reported studies of associations between beta-blocker underuse and secondary prevention of MI. Additional studies were identified by a hand search of references of original or review articles.

STUDY SELECTION AND DATA EXTRACTION

English-language human studies were selected and analyzed.

DATA SYNTHESIS

Associations were observed in studies of beta-blocker use as secondary prevention of MI. A lower rate of beta-blocker treatment occurred in older patients and in patients with comorbid conditions such as diabetes, heart failure, chronic obstructive pulmonary disease, asthma, and peripheral arterial disease. In addition, underuse was attributed to the perception of high rates of adverse events associated with beta-blockers. beta-Blocker use as secondary prevention of an MI can lead to a 19-48% decrease in mortality and up to a 28% decrease in reinfarction rates. Nonetheless, beta-blockers are significantly underused in many patient populations due to concomitant disease states. Due to their normal physiologic deterioration, the elderly are at an increased risk of low cardiac output and bradycardia when given a beta-blocker; therefore, they should be started on a low dose that is then slowly titrated. In diabetic patients, beta-blockers can impair glucose control leading to hypoglycemia; therefore, post-MI diabetic patients must routinely monitor their blood glucose levels. In patients with decompensated heart failure, beta-blocker use can lead to further cardiac depression, but lower oral starting doses with slow titration can reduce this risk. beta-Blockers can induce bronchospasm in patients with chronic obstructive pulmonary disease or asthma, but cardioselective beta-blockers and appropriate use of medications such as albuterol can minimize these effects. Finally, in patients with peripheral arterial disease, with the exception of hypertensive patients with Reynaud's phenomenon, beta-blockers can be used safely. The only absolute contraindications to beta-blockers are severe bradycardia, preexisting sick sinus syndrome, second- and third-degree atrioventricular block, severe left ventricular dysfunction, active peripheral vascular disease with rest ischemia, or reactive airway disease so severe that airway support is required.

CONCLUSIONS

Overall, the cardiovascular benefits of beta-blockers as secondary prevention of MI significantly outweigh the risks associated with their use.

Quality of care of nursing home residents hospitalized with heart failure

OBJECTIVES

To determine whether the quality of heart failure (HF) care of hospitalized nursing home (NH) residents is different from that of patients admitted from other locations.

DESIGN

Retrospective chart review.

SETTING

Nursing home residents discharged from hospitals.

PARTICIPANTS

Medicare beneficiaries aged 65 and older.

MEASUREMENTS

Subjects were discharged with a primary discharge diagnosis of HF in Alabama in 1994. They were categorized as having been admitted from a NH or other locations. Bivariate logistic regression analysis was used to estimate crude odds ratios (ORs) and 95% confidence intervals (CIs) for left ventricular function (LVF) evaluation and angiotensin-converting enzyme (ACE) inhibitor use for NH residents relative to nonresidents. Multivariate generalized linear models were developed to determine independence of associations.

RESULTS

Subjects (N = 1,067 years) had a mean age +/- standard deviation of 79 +/- 7.4, 60% were female, and 18% were African Americans. Fewer NH residents (n = 95) received LVF evaluation (39% vs 60%, P <.001) and ACE inhibitors (50% vs 72%, P =.111). NH residents had lower odds for LVF evaluation (OR = 0.42, 95% CI = 0.27-0.64). The odds for ACE inhibitor use, although of similar magnitude, did not reach statistical significance (OR = 0.40, 95% CI = 0.12-1.28). After adjustment of patient and care characteristics, admission from a NH was significantly associated with lower LVF evaluation (adjusted OR = 0.64, 95% CI = 0.49-0.82) but not with ACE inhibitor use (adjusted OR = 0.59, 95% CI = 0.16-2.14).

CONCLUSIONS

Quality of HF care received by hospitalized NH residents was lower than that received by others. Further studies are needed to determine reasons for the lack of appropriate evaluation and treatment of NH patients with HF who are admitted to hospitals.

End-of-life decision making: a qualitative study of elderly individuals

OBJECTIVE

To identify the desired features of end-of-life medical decision making from the perspective of elderly individuals.

DESIGN

Qualitative study using in-depth interviews and analysis from a phenomenologic perspective.

SETTING

A senior center and a multilevel retirement community in Los Angeles.

PARTICIPANTS

Twenty-one elderly informants (mean age 83 years) representing a spectrum of functional status and prior experiences with end-of-life decision making.

MAIN RESULTS

Informants were concerned primarily with the outcomes of serious illness rather than the medical interventions that might be used, and defined treatments as desirable to the extent they could return the patient to his or her valued life activities. Advanced age was a relevant consideration in decision making, guided by concerns about personal losses and the meaning of having lived a "full life." Decision-making authority was granted both to physicians (for their technical expertise) and family members (for their concern for the patient's interests), and shifted from physician to family as the patient's prognosis for functional recovery became grim. Expressions of care, both by patients and family members, were often important contributors to end-of-life treatment decisions.

CONCLUSIONS

These findings suggest that advance directives and physician-patient discussions that focus on acceptable health states and valued life activities may be better suited to patients' end-of-life care goals than those that focus on specific medical interventions, such as cardiopulmonary resuscitation. We propose a model of collaborative surrogate decision making by families and physicians that encourages physicians to assume responsibility for recommending treatment plans, including the provision or withholding of specific life-sustaining treatments, when such recommendations are consistent with patients' and families' goals for care.

Comparison of acute myocardial infarct size to two-year mortality in patients <65 to those > or =65 years of age

Older patients have higher in-hospital and longer term mortality after myocardial infarction. To determine if larger infarct size correlates with this observation, myocardium at risk was measured on arrival to the hospital in 347 patients with acute myocardial infarction, and final infarct size was measured at hospital discharge in a subset of 274 of these patients. Myocardium at risk and final infarct size were quantified by tomographic technetium-99m sestamibi imaging. Statistical analyses examined the associations between age, myocardium at risk, final infarct size, and both in-hospital and postdischarge mortality. Median value for age was 64 years, and myocardium at risk was 24% and final infarct size was 12% of the left ventricle. There was no correlation between age and myocardium at risk (r = 0.04, p = NS) or final infarct size (r = 0.06, p = NS). In-hospital mortality was 4% overall and was 2% for patients <65 years old versus 6% for those > or =65 years old (chi-square 11.3, p<0.001). In-hospital mortality was not associated with myocardium at risk (chi square <1, p = NS). For the subset of 274 patients in whom final infarct size was measured, the subsequent 2-year mortality rate was 3% and was independently associated with both age (chi-square 15.6, p<0.001) and final infarct size (chi-square 9.7, p = 0.002). Survival was excellent for patients who were either <65 years old (2-year mortality 1%) or had an infarct size <12% (2-year mortality 0%). For patients > or =65 years old with infarct size > or =12%, 2-year mortality was 13%. These results demonstrate that older patients do not have larger infarcts. Advanced age is associated with higher in-hospital and postdischarge mortality, independent of infarct size.

Management and outcome of acute myocardial infarction in older patients in the thrombolytic era

OBJECTIVE

Acute myocardial infarction (AMI) is an important cause of mortality and morbidity in older patients. The aim of this study was to determine the proportion of unselected admissions with AMI that is older than 75 years and to examine management and outcomes in this group.

DESIGN

An historical cohort study of consecutive unselected admissions with AMI identified using the Hospital In Patient Enquiry (HIPE) database and validated according to MONICA criteria for definite or probable AMI.

SETTING

An acute cardiac unit in a university teaching hospital/cardiac tertiary referral center.

RESULTS

Of 1059 patients, 606 (57%) were older than 65 years and 309 (29.2%) were older than 75 years. Mean age in this group was 80.5 years. Hospital mortality was almost twice as high as in patients younger than 75 years (28% vs 15%, P < .001), and age was an independent predictor of short- and long-term mortality following AMI. Women constituted a significantly higher proportion of older patients. Family history of AMI and cigarette smoking were less prevalent in older patients. Mean cholesterol was lower and comorbidities were higher. Other baseline characteristics, including previous AMI, did not differ. However older patients were less likely to receive thrombolysis (13% vs 36%, P < .001), aspirin (76% vs 86%, P < .01), or beta-blockers (25% vs 51%, P < .001) and were less likely to undergo cardiac catheterization or revascularization. Only 53% were admitted to coronary care.

CONCLUSION

Patients more than age 75 comprise almost one-third of patients with AMI and have a poor prognosis. Although age is an independent predictor of mortality following AMI, suboptimal management may contribute to the high mortality in these patients.

Differences in discharge medication after acute myocardial infarction in patients with HMO and fee-for-service medical insurance

OBJECTIVE

To assess the impact of fee-for-service (FFS) versus HMO medical insurance coverage on receipt of aspirin, beta-blockers, and calcium channel blockers at the time of hospital discharge following an acute myocardial infarction.

DESIGN

Prospective, population-based study.

SETTING

All 16 community and tertiary care hospitals in the metropolitan area of Worcester, Massachusetts.

PATIENTS

The study population consisted of patients under 65 years of age hospitalized with a validated acute myocardial infarction in all hospitals in the Worcester (Massachusetts) Standard Metropolitan Statistical Area (1990 census estimate, 437,000) during 1986, 1988, 1990, 1991, and 1993.

MEASUREMENTS AND MAIN RESULTS

After adjustment for demographic and clinical variables as well as study year, the odds ratios for receipt of each medication for patients with HMO insurance compared with FFS were 1.05 (95% confidence interval [CI] 0.77, 1.44) for aspirin, 1.32 (95% CI 0.98, 1.76) for beta-blockers, and 0.72 (95% CI 0.54, 0.96) for calcium channel blockers. Examination of temporal trends in utilization of these agents suggests that observed decreases in use of calcium channel blockers and increases in use of beta-blockers over the period under study occurred more rapidly for HMO than for FFS patients.

CONCLUSIONS

Overall, use of aspirin and beta-blockers was comparable among HMO and FFS patients and use of calcium channel blockers (deemed less effective or ineffective for secondary prevention) was lower among HMO patients. Differential adoption, over time, of evidence-based prescribing practices for medications between HMO and FFS patients who have had a myocardial infarction warrants further study.

Complications of acute myocardial infarction in patients > or = 90 years of age

Forty consecutive 90-year-old persons with an acute myocardial infarction were studied to describe the noncardiac complications of their care. Common negative consequences of hospitalization of these patients included delirium, pressure ulcers, and poor ambulatory status at discharge.

Coronary angioplasty for elderly patients with "high risk" unstable angina: short-term outcomes and long-term survival

OBJECTIVES

We sought to compare the short- and long-term mortality rates in patients > or = 70 years old with unstable angina undergoing percutaneous transluminal coronary angioplasty (PTCA) with predicted coronary artery bypass graft surgery (CABG) short-term and U.S. census long-term mortality rates.

BACKGROUND

Coronary angioplasty is an alternative revascularization strategy for patients with medically refractory rest angina and a high risk of adverse outcomes with CABG. Patients > or = 70 years old are a specific high risk subset.

METHODS

A total of 131 consecutive patients aged > or = 70 years with unstable angina underwent PTCA; 82 (62%) of 131 had been refused CABG. Mortality over time was obtained from the Veterans Affairs Beneficiary Index Records Locator Subsystem. Predicted 30-day CABG-associated mortality was obtained from the Veterans Affairs Cardiac Risk Assessment Model. Mortality over time was expressed with Kaplan-Meier curves.

RESULTS

The observed 30-day angioplasty survival rate was 87% compared with the predicted surgical 30-day survival rate of 85.5%. In those patients who survived 6 months after angioplasty (84%), their subsequent 1-, 2-, 3-, 4- and 5-year survival rates were comparable to age-matched subjects in the U.S. census. Mortality in certain subsets known to be at very high risk for CABG-for example, patients who had a previous CABG-was not high in this cohort of elderly subjects. The extremely high risk subsets identified in this PTCA cohort (shock, heart failure, pressors required, balloon pump required) were relatively infrequent subsets.

CONCLUSIONS

For selected elderly patients with unstable angina deemed to be at "high risk" or even "prohibitive risk" for CABG, PTCA is an alternative revascularization strategy. The long-term mortality of successfully treated elderly patients is comparable to age-matched subjects. A prospective, multicenter, randomized trial of CABG versus PTCA, which includes patients > or = 70 years old, is being conducted (Veterans Affairs Cooperative Study 385: AWESOME).