Robert F. DeBusk

Smoking Cessation after Acute Myocardial Infarction: Effects of a Nurse-Managed Intervention

STUDY OBJECTIVE To determine the effect of a nurse-managed intervention for smoking cessation in patients who have had a myocardial infarction. DESIGN Randomized, with a 6-month treatment period and a 6-month follow-up. SETTING Kaiser Foundation hospitals in Redwood City, Santa Clara, Hayward, and San Jose, California. PATIENTS Sequential sample of 173 patients, 70 years of age or younger, who were smoking before hospitalization for acute myocardial infarction. Eighty-six patients were randomly assigned to the intervention and 87 to usual care; 130 patients (75%) completed the study and were available for follow-up. INTERVENTION Nurse-managed and focused on preventing relapse to smoking, the intervention was initiated in the hospital and maintained thereafter primarily through telephone contact. Patients were given an 18-page manual that emphasized how to identify and cope with high-risk situations for smoking relapse. MEASUREMENTS AND MAIN RESULTS One year after myocardial infarction, the smoking cessation rate, verified biochemically, was 71% in the intervention group compared with 45% in the usual care group, a 26% difference (95% CI, 9.5% to 42.6%). Assuming that all surviving patients lost to follow-up were smoking, the 12-month smoking cessation rate was 61% in the intervention group compared with 32% in the usual care group, a 29% difference (95% CI, 14.5% to 43.5%). Patients who either resumed smoking within 3 weeks after infarction or expressed little intention of stopping in the hospital were unlikely to have stopped by 12 months. CONCLUSIONS A nurse-managed smoking cessation intervention largely conducted by telephone, initiated in the hospital, and focused on relapse prevention can significantly reduce smoking rates at 12 months in patients who have had a myocardial infarction.

Influence of regular aerobic exercise on psychological health: a randomized, controlled trial of healthy middle-aged adults

Although a variety of psychological benefits have been attributed to regular exercise, few experimentally controlled studies of healthy individuals currently exist. One hundred twenty healthy, sedentary, middle-aged men and women were randomly assigned to either a 6-month home-based aerobic exercise training program or to an assessment-only control condition. Adherence across the 6-month period was found by both self-report and heart rate microprocessor methods to exceed 75% in both sexes. To assess changes in a variety of psychological variables over time, a 14-item Likert rating scale was completed and returned on a biweekly basis throughout the 6-month period. Slope analyses conducted on the 11 items attaining acceptable test-retest reliability coefficients showed significant between-groups differences on the 3 items most closely associated with the actual physical changes that occurred with exercise (all ps less than .004). Implications in relation to repeated measurement of psychological changes in nonclinical populations and the determination of the relevant population-, activity-, and program-specific parameters involved are discussed.

Strategies for increasing early adherence to and long-term maintenance of home-based exercise training in healthy middle-aged men and women

Two studies were undertaken to compare strategies for the adoption and maintenance of moderate-intensity, home-based exercise training. In the study of adoption, 52 men and women who had served for 6 months as controls for a study of moderate-intensity, home-based exercise training received 30 minutes of baseline instruction. They were then randomized to receive continuing instruction and support through 10 staff-initiated telephone contacts of 5 minutes each every 2 weeks, or to receive no telephone contacts. In subjects receiving telephone contacts, peak oxygen uptake increased significantly after 6 months, whereas no increase was observed in subjects receiving no staff support (p less than 0.05). In the maintenance study, 51 men and women who had significantly increased their peak oxygen uptake by 6 months of moderate-intensity, home-based exercise training were randomized to undergo daily self-monitoring and receive adherence instructions, or undergo weekly self-monitoring only, during a second 6-month period of training. Subjects performing daily self-monitoring reported completing significantly more exercise training sessions during the 6 months of training than subjects performing weekly self-monitoring; functional capacity in both groups remained higher than before training (p less than 0.05). Taken together, these studies suggest that brief baseline instruction followed by continuing telephone contact with staff can be used to help people adopt a moderate-intensity, home-based exercise training program that can be maintained by simple self-monitoring strategies.

Medically directed at-home rehabilitation soon after clinically uncomplicated acute myocardial infarction: A new model for patient care

Medically directed at-home rehabilitation was compared with group rehabilitation which began 3 weeks after clinically uncomplicated acute myocardial infarction (AMI) in 127 men, mean age 53 +/- 7 years. Between 3 and 26 weeks after AMI, adherence to individually prescribed exercise was equally high (at least 71%), the increase in functional capacity equally large (1.8 +/- 1.0 METs) and nonfatal reinfarction and dropout rates equally low (both 3% or less) in the 66 men randomized to home training and the 61 men randomized to group training. No training-related complications occurred in either group. The low rate of reinfarction and death (5% and 1%, respectively) in the study as a whole, which included 34 patients with no training and 37 control patients, reflected a stepwise process of clinical evaluation, exercise testing at 3 weeks and frequent telephone surveillance of patients who underwent exercise training. Medically directed at-home rehabilitation has the potential to increase the availability and to decrease the cost of rehabilitating low-risk survivors of AMI.

Report of the National Heart, Lung, and Blood Institute Working Group on Outcomes Research in Cardiovascular Disease

The National Heart, Lung, and Blood Institute convened a working group on outcomes research in cardiovascular disease (CVD). The working group sought to provide guidance on research priorities in outcomes research related to CVD. For the purposes of this document, “outcomes research” is defined as investigative endeavors that generate knowledge to improve clinical decision making and healthcare delivery to optimize patient outcomes. The working group identified the following priority areas: (1) national surveillance projects for high-prevalence CV conditions; (2) patient-centered care; (3) translation of the best science into clinical practice; and (4) studies that place the cost of interventions in the context of their real-world effectiveness. Within each of these topics, the working group described examples of initiatives that could serve the Institute and the public. In addition, the group identified the following areas that are important to the field: (1) promotion of the use of existing data; (2) facilitation of collaborations with other federal agencies; (3) investigations into the basic science of outcomes research, with an emphasis on methodological advances; (4) strengthening of appropriate study sections with individuals who have expertise in outcomes research; and (5) expansion of opportunities to train new outcomes research investigators. The working group concluded that a dedicated investment in CV outcomes research could directly improve the care delivered in the United States.

Home versus group exercise training for increasing functional capacity after myocardial infarction.

To evaluate the efficacy of exercise training for increasing functional capacity in the 6 months after clinically uncomplicated myocardial infarction, 198 men 52 +/- 9 years of age participated in a training study. They were randomly assigned to one of four exercise protocols: 8 to 26 weeks of training at home (group 1, n = 66) or in a group program (group 2, n = 61) following treadmill testing performed 3 weeks after infarction, treadmill testing at 3 weeks without subsequent training (group 3, n = 34), and treadmill testing for the first time at 26 weeks (control, n = 37). At 26 weeks functional capacity was significantly higher in patients training at home or in a group program than that in patients without training or in control patients: 8.1 +/- 1.5, 8.5 +/- 1.3, 7.5 +/- 1.8, and 7.0 +/- 1.7 METs, respectively (p less than .05 and p less than .001). No significant differences in functional capacity were noted between patients training at home and those in a group program. No training-related complications occurred. Home and group training are equally effective in increasing functional capacity of low-risk patients after myocardial infarction.

The prognostic significance of serial exercise testing after myocardial infarction.

Serial treadmill exercise testing (mean 5.5 tests/patient) was used to evaluate the prognosis of 200 males (mean age 53 years) without clinical heart failure or unstable angina pectoris 3 weeks after acute myocardial infarction (MI). Exercise-induced ischemic ST-segment depression greater than or equal to 0.2 mV 3 weeks after MI was significantly more prevalent in patients with subsequent cardiac arrest (100%) or coronary artery bypass graft surgery (64%) than in patients without subsequent events within 2 years of infarction (35%) (p less than 0.05). Exercise-induced ventricular arrhythmia on multiple tests 5-52 weeks after MI was more prevalent in patients with recurrent myocardial infarction (90%) than in patients without subsequent events (47%) (p less than 0.001). By contrast, exercise-induced ventricular arrhythmia on a single test at 3 weeks was a less powerful predictor of subsequent cardiac events. Exercise-induced ischemia 3 weeks after MI predicted early fatal events, while ventricular arrhythmia on serial testing predicted later nonfatal events.

Exercise training soon after myocardial infarction

Abstract To assess the cardiovascular effects of exercise training soon after clinically uncomplicated myocardial infarction, 70 men (mean age 54 years) underwent gymnasium training (no. = 28), home training (no. = 12) or no training (no. = 30) 3 to 11 weeks after the acute event. During this 8 week interval functional capacity increased significantly ( P P

Stepwise risk stratification soon after acute myocardial infarction.

A stepwise rise stratification procedure sequentially combining historical and clinical characteristics and treadmill exercise test results was applied to 702 consecutive men aged less than or equal to 70 years who were alive 21 days after acute myocardial infarction (MI). Historical characteristics alone (prior MI and prior angina or recurrence of pain in the coronary care unit) identified 10% of patients with the highest rate of reinfarction and death within 6 months (18%). Clinical contraindications to exercise testing identified another 40% of patients with an intermediate rate of cardiac events (6.4%). In the 50% of patients who underwent treadmill testing 3 weeks after MI, the rate of cardiac events within 6 months was 4.4%: 3.9% in patients with a negative test and 9.7% in patients with a positive test (ischemic ST-segment depression greater than or equal to 0.2 mV and a peak heart rate less than or equal to 135 beats/min). Patients with negative treadmill tests, who comprised 46% of patients less than or equal to 70 years and 53% of patients less than or equal to 60 years, had a cardiac death rate of less than 2% in the 6 months after MI. The stepwise classification procedure correctly classified 72% of patients with hard medical events within 6 months. Thus, most patients who experience subsequent cardiac events are correctly classified on the basis of historical and clinical risk characteristics. In patients without these risk characteristics, early treadmill testing is useful for further discriminating high-risk from very low risk patients.

A new method for evaluating antiarrhythmic drug efficacy.

To develop standards for distinguishing antiarrhythmic drug effect from spontaneous variability of premature ventricular complexes (PVCs), 21 males (mean age 56 ± 8 years) with chronic ischemic heart disease and PVCs underwent symptom-limited treadmill exercise testing and 24-hour ambulatory monitoring before and after 2 weeks of placebo medication. Linear regression analysis was used to describe the relationship between baseline and placebo PVC frequency for various indexes of ventricular ectopic activity and to establish 95% and 99% one-tailed confidence intervals for this relationship within the group of 21 patients. The lower limit of baseline PVC frequency for which the procedure could distinguish a placebo from a true drug response, termed the “sensitivity threshold,” was an average frequency of 2.2 PVCs/hour for ambulatory electrocardiographic monitoring and 1.2 PVCs/min for treadmill exercise testing. All patients exceeded the sensitivity threshold on baseline ambulatory ECGs, but only 38% of patients did so on baseline treadmill exercise tests. To establish antiarrhythmic efficacy with 95% confidence, the minimal percent reduction of PVCs between baseline and placebo visits was 68% for treadmill exercise testing and 65% for ambulatory electrocardiography. Although these standards were developed in patients with chronic ischemic heart disease, the model can be used to establish antiarrhythmmic drug efficacy in any patient group.