Secondary prevention after acute myocardial infarction

doi:10.1016/0002-9149(93)91058-P

The American Journal of Cardiology

Volume 72, Issue 11, 1 October 1993, Pages 759-762

https://doi.org/10.1016/0002-9149(93)91058-P Get rights and content

Abstract

The hypothesis that 6 months after acute myocardial infarction, adoption of secondary prevention activities would be higher, quality of life better, and blood cholesterol lower in patients randomly allocated to a mail-wit intervention program than in those receiving usual care was tested. Patients were aged <70 years, admitted to hospitals in and around Newcastle, Australia with a suspected heart attack and discharged alive from the hospital. Cluster randomization, based on the patient's family practitioner, was used to allocate consenting patients to an intervention or usual care group. A low-cost mail-out program was designed to help patients reduce dietary fat, obtain regular exercise by walking and (for smokers only) to quit smoking. Supplementary telephone contact was also used. In addition, a letter was sent to the family doctor regarding the benefit of aspirin and β blockers for secondary prevention. Of eligible patients, 71% participated, and 79% of the 213 intervention subjects and 87% of the 237 usual care ones returned a 6-month follow-up questionnaire. Self-reported fat intake was significantly lower, an “emotional” score obtained from a quality-of-life questionnaire was significantly higher in the intervention than in the usual care group, and “physical” and “social” scores for quality of life were slightly higher. Blood cholesterol level and other variables were not different between the groups at 6 months. Simple low-cost programs providing support and advice on lifestyle change may be beneficial, particularly in improving patients' perceived quality of life.

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Cited by (79)

Exercise-Based Cardiac Rehabilitation for Coronary Heart Disease Cochrane Systematic Review and Meta-Analysis
2016, Journal of the American College of Cardiology
Citation Excerpt :
Exercise-based CR programs were typically delivered in a supervised hospital/center-based setting, either exclusively or in combination with some maintenance home exercise sessions. Fifteen studies were conducted in an exclusively home-based setting (22–36). Whereas the primary mode of exercise training across all studies was aerobic, the overall or average duration, frequency, and intensity of sessions varied considerably across studies.
Although recommended in guidelines for the management of coronary heart disease (CHD), concerns have been raised about the applicability of evidence from existing meta-analyses of exercise-based cardiac rehabilitation (CR).
The goal of this study is to update the Cochrane systematic review and meta-analysis of exercise-based CR for CHD.
The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, and Science Citation Index Expanded were searched to July 2014. Retrieved papers, systematic reviews, and trial registries were hand-searched. We included randomized controlled trials with at least 6 months of follow-up, comparing CR to no-exercise controls following myocardial infarction or revascularization, or with a diagnosis of angina pectoris or CHD defined by angiography. Two authors screened titles for inclusion, extracted data, and assessed risk of bias. Studies were pooled using random effects meta-analysis, and stratified analyses were undertaken to examine potential treatment effect modifiers.
A total of 63 studies with 14,486 participants with median follow-up of 12 months were included. Overall, CR led to a reduction in cardiovascular mortality (relative risk: 0.74; 95% confidence interval: 0.64 to 0.86) and the risk of hospital admissions (relative risk: 0.82; 95% confidence interval: 0.70 to 0.96). There was no significant effect on total mortality, myocardial infarction, or revascularization. The majority of studies (14 of 20) showed higher levels of health-related quality of life in 1 or more domains following exercise-based CR compared with control subjects.
This study confirms that exercise-based CR reduces cardiovascular mortality and provides important data showing reductions in hospital admissions and improvements in quality of life. These benefits appear to be consistent across patients and intervention types and were independent of study quality, setting, and publication date.
Efficacy of exercise-based cardiac rehabilitation post-myocardial infarction: A systematic review and meta-analysis of randomized controlled trials
2011, American Heart Journal
Citation Excerpt :
In sensitivity analyses, we first repeated our primary analyses excluding RCTs with no events in both arms and then repeated analyses excluding RCTs with no events in 1 arm to examine the effect of zero-event RCTs. In addition, because 1 RCT10 did not specify what criteria were used for MI diagnosis, we excluded this RCT in additional sensitivity analyses. Because one of the largest RCTs was published in 1979,11 we excluded this RCT in a sensitivity analysis.
Exercise-based cardiac rehabilitation (CR) remains an underused tool for secondary prevention post–myocardial infarction (MI). In part, this arises from uncertainty regarding the efficacy of CR, particularly with respect to reinfarction, where previous studies have failed to show consistent benefit. We therefore undertook a meta-analysis of randomized controlled trials (RCTs) to (1) estimate the effect of CR on cardiovascular outcomes and (2) examine the effect of CR program characteristics on the magnitude of CR benefits.
We systematically searched MEDLINE as well as relevant bibliographies to identify all English-language RCTs examining the effects of exercise-based CR among post-MI patients. Data were aggregated using random-effects models. Stratified analyses were conducted to examine the impact of RCT-level characteristics on treatment benefits.
We identified 34 RCTs (N = 6,111). Overall, patients randomized to exercise-based CR had a lower risk of reinfarction (odds ratio [OR] 0.53, 95% CI 0.38-0.76), cardiac mortality (OR 0.64, 95% CI 0.46-0.88), and all-cause mortality (OR 0.74, 95% CI 0.58-0.95). In stratified analyses, treatment effects were consistent regardless of study periods, duration of CR, or time beyond the active intervention. Exercise-based CR had favorable effects on cardiovascular risk factors, including smoking, blood pressure, body weight, and lipid profile.
Exercise-based CR is associated with reductions in mortality and reinfarction post-MI. Our secondary analyses suggest that even shorter CR programs may translate into improved long-term outcomes, although these results need to be confirmed in an RCT.
Meta-analysis of interventions to increase physical activity among cardiac subjects
2009, International Journal of Cardiology
Extensive primary research has tested interventions to increase physical activity (PA) among adults with cardiovascular disease. This meta-analysis integrates the extant research about how to increase PA in cardiac samples.
Extensive literature searching located published and unpublished intervention studies that measured PA outcomes. Results were coded from primary studies. Fixed- and random-effects meta-analytic procedures included moderator analyses.
Data were synthesized across 11,877 subjects from 79 eligible research reports. The overall mean PA effect size for 2-group comparisons was 0.35 (higher mean for treatment than control), which is consistent with a difference of 1984 kcal/week for treatment subjects versus 1615 for control subjects. The fitness effect size for 2-group comparisons was .17. Other statistically significantly positive 2-group effect sizes were .24 for quality of life and .23 for subsequent cardiac events. Effect sizes for anthropometric measures and blood pressure did not differ significantly from 0. Exploratory moderator analyses found large effect sizes for PA among studies that had (1) an exclusive focus on PA versus diverse health behaviors, (2) more contact between interventionists and subjects, (3) supervised exercise sessions, (4) fitness testing, (5) face-to-face encounters versus mediated intervention delivery, and (6) more minutes of activity per week. Effect sizes were unrelated to funding status, dissemination vehicle, gender distribution, or attrition rate.
These findings document that interventions can be effective in increasing PA among patients with cardiovascular diseases. Primary research should compare interventions in randomized trials to confirm causal relationships.
Meta-analysis of patient education interventions to increase physical activity among chronically ill adults
2008, Patient Education and Counseling
This meta-analysis integrates primary research testing the effect of patient education to increase physical activity (PA) on behavior outcomes among adults with diverse chronic illnesses.
Extensive literature searching strategies located published and unpublished intervention studies that measured PA behavior outcomes. Primary study results were coded. Fixed- and random-effects meta-analytic procedures included moderator analyses.
Data were synthesized across 22,527 subjects from 213 samples in 163 reports. The overall mean weighted effect size for two-group comparisons was 0.45 (higher mean for treatment than control). This effect size is consistent with a difference of 48 min of PA per week or 945 steps per day. Preliminary moderator analyses suggest interventions were most effective when they targeted only PA behavior, used behavioral strategies (versus cognitive strategies), and encouraged PA self-monitoring. Differences among chronic illnesses were documented. Individual strategies unrelated to PA outcomes included supervised exercise sessions, exercise prescription, fitness testing, goal setting, contracting, problem solving, barriers management, and stimulus/cues. PA outcomes were unrelated to gender, age, ethnicity, or socioeconomic distribution among samples.
These findings suggest that some patient education interventions to increase PA are effective, despite considerable heterogeneity in the magnitude of intervention effect.
Moderator analyses are preliminary and provide suggestive evidence for further testing of interventions to inform practice.
Home-based cardiac rehabilitation compared with centre-based rehabilitation and usual care: A systematic review and meta-analysis
2006, International Journal of Cardiology
To determine the effectiveness of home-based cardiac rehabilitation programmes compared with (i) usual care and (ii) supervised centre-based cardiac rehabilitation on mortality, health related quality of life and modifiable cardiac risk factors of patients with coronary heart disease.
Systematic review and meta-analysis of randomised controlled trials. Main outcome measures: mortality, smoking cessation, exercise capacity, systolic blood pressure, total cholesterol, psychological status, and health related quality of life.
Eighteen included trials for home versus usual rehabilitation and six trials of home versus supervised centre-based rehabilitation were identified. The home-based interventions were clinically heterogeneous, trials often small, with quality poorly reported. Compared with usual care, home-based cardiac rehabilitation had a 4 mm Hg (95% CI 6.5, 1.5) greater reduction in systolic blood pressure, and a reduced relative risk of being a smoker at follow-up (RR 0.71, 95% CI 0.51, 1.00). Differences in exercise capacity, total cholesterol, anxiety and depression were all in favour of the home-based group. In patients post-myocardial infarction exercise capacity was significantly improved in the home rehabilitation group by 1.1 METS (95% CI 0.2, 2.1) compared to usual care. The comparison of home-based with supervised centre-based cardiac rehabilitation revealed no significant differences in exercise capacity, systolic blood pressure and total cholesterol.
Current evidence does not show home-based cardiac rehabilitation to be significantly inferior to centre-based rehabilitation for low-risk cardiac patients. However, the numbers of patients included are less than 750 and ongoing trials will contribute to the debate on the acceptability, effectiveness and cost-effectiveness of home-based cardiac rehabilitation.
A meta-analysis of randomized control trials of home-based secondary prevention programs for coronary artery disease
2010, European Journal of Cardiovascular Prevention and Rehabilitation
A variety of different types of secondary prevention programs for coronary heart disease (CHD) exist. Home-based programs have become more common and may be more accessible or preferable to some patients. This review compared the benefits and costs of home-based programs with usual care and cardiac rehabilitation.
A meta-analysis following a systematic search of 19 databases, existing reviews, and references was designed. Studies evaluated home-based interventions that addressed more than one main CHD risk factor using a randomized trial with a usual care or cardiac rehabilitation comparison group with data extractable for CHD patients only and reported in English as a full article or thesis.
Thirty-nine articles reporting 36 trials were reviewed. Compared with usual care, home-based interventions significantly improved quality of life [weighted mean difference: 0.23; 95% confidence interval (95% CI): 0.02–0.45], systolic blood pressure (weighted mean difference: -4.36 mmHg; 95% CI: -6.50 to -2.22), smoking cessation (difference in proportion: 14%; 95% CI: 0.02–0.26), total cholesterol (standardized mean difference: -0.33; 95% CI: -0.57 to -0.08), and depression (standardized mean difference: -0.33; 95% CI: -0.59 to -0.07). Effect sizes were small to moderate and trials were of low-to-moderate quality. Comparisons with cardiac rehabilitation could not be made because of the small number of trials and high levels of heterogeneity.
Home-based secondary prevention programs for CHD are an effective and relatively low-cost complement to hospital-based cardiac rehabilitation and should be considered for stable patients less likely to access or adhere to hospital-based services.

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^☆: This work was supported by a grant from the National Health and Medical Research Council of Australia.

View full text

Secondary prevention after acute myocardial infarction☆

Abstract

J Clin Epidemiol

Aust J Public Health

Am J Cardiol

Methodological issues in interpreting trends in MONICA event rates

Rev Epidemiol Sante Publigue

The value of lowering cholesterol after myocardial infarction

N Engl J Med

Cardiac rehabilitation after myocardial infarction: combined experience of randomised clinical trials

JAMA