Impact of cardiac rehabilitation participation on patient-reported lifestyle changes one year after myocardial infarction

In the 2016 European guidelines on cardiovascular disease prevention, the participation in a cardiovascular rehabilitation (CR) programme after an acute coronary event is recommended with a class IA recommendation to improve patient outcomes.1 Comprehensive CR programs with optimisation of cardiovascular medication and risk factors reduce all-cause mortality and morbidity.2,3 However, recent data suggest that beneficial effects reached during CR diminish over time.4 The aim of this study was to analyse lifestyle changes one year after a ST-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) according to CR participation. We analysed patient data from the Acute Myocardial Infarction in Switzerland registry (AMIS Plus) from 2013 to 2017. The AMIS Plus Registry is a Swiss nationwide cohort study collecting data on hospital admissions for acute myocardial infarction (AMI) since 1997. Detailed study methods for AMIS Plus have been published previously.2,5 Patients are additionally contacted by phone one year after AMI for a follow-up if they gave their informed consent. Self-reported information on CR participation, lifestyle and risk factor management were obtained during the telephone follow-up one year after AMI. Components of CR in Switzerland are defined by the Swiss Working Group for Cardiovascular Prevention, Rehabilitation and Sports Cardiology (SCPRS) and include a defined number of exercise sessions, psychological, dietary and smoking counselling (see www.SCPRS.ch). Categorical variables are presented as frequencies and percentages, and the Fisher’s exact test was used for the comparison of the baseline characteristics between patients who participated in CR versus those who did not. Continuous variables are presented as mean (standard deviation) and the T-Test was used for group comparison. Logistic regression was used for univariable and multivariable analyses of the impact of CR on lifestyle changes. From 4122 patients, 830 (20.1%) refused to participate in follow-up and 298 (9%) were lost to follow-up (5.7% not reachable, 3.3% death). A total of 2157 patients participated in CR and 749 did not attend CR (Table 1). CR patients were younger (62.4 y vs 69.8 y), more often male and smokers, and had more STEMI than non-CR counterparts. Less CR patients had hypertension and diabetes at baseline, while no difference in dyslipidaemia and overweight/obesity was observed. Patient characteristics during hospitalisation according to rehabilitation participation. P2Y12 inhibitors: clopidogrel, prasugrel or ticagrelor; ACEI: angiotensin-converting enzyme inhibitor; ARB: angiotensin II receptor antagonist; ASA: acetylsalicylic acid; PCI: percutaneous coronary intervention; SD: standard deviation; BMI: body mass index; STEMI: ST-elevation myocardial infarction. Patient characteristics during hospitalisation according to rehabilitation participation. P2Y12 inhibitors: clopidogrel, prasugrel or ticagrelor; ACEI: angiotensin-converting enzyme inhibitor; ARB: angiotensin II receptor antagonist; ASA: acetylsalicylic acid; PCI: percutaneous coronary intervention; SD: standard deviation; BMI: body mass index; STEMI: ST-elevation myocardial infarction. A total of 49% of CR patients reported an increase in physical activity compared to 20.6% without CR, while physical activity decreased after one year in 13.9% CR patients and 23.9% of patients without CR (all p < 0.001) (Table 2). After correction for age (per additional year) and gender, CR was an independent predictor for increased physical activity, even after adjustment for comorbidities (Charlson comorbidity index > 1) (odds ratio (OR) 3.078; 95% confidence interval (CI) 2.50–3.79). Unadjusted impact of CR on lifestyle changes one year after myocardial infarction. MI: myocardial infarction; AMI: acute myocardial infarction; OR: odds ratio; CI: confidence interval; BMI: body mass index. Unadjusted impact of CR on lifestyle changes one year after myocardial infarction. MI: myocardial infarction; AMI: acute myocardial infarction; OR: odds ratio; CI: confidence interval; BMI: body mass index. More CR patients reported having stopped smoking after one year (57.7 vs 37.3%; p < 0.001) (Table 2). Participation in CR was the strongest predictor for successful smoking stop with an OR of 2.279 (95% CI 1.69–3.08; p < 0.001), while age and gender had no impact. After correction for age, gender and CR, there was a high impact of smoking cessation on increase in physical activity, with an OR of 1.834 (95% CI 1.42–2.37; p < 0.001). Persistent dietary changes were reported in 53% of CR patients, and in 28.2% of patients without CR (p < 0.001). In the group of patients with a body mass index (BMI) > 30 at hospitalisation, dietary changes were reported in 61.6% vs 35.9% (CR vs no CR, p < 0.001) (Table 2). A total of 32.5% of CR patients lost weight (25.3% without CR; p < 0.001), while weight increased in 19.2% of CR patients (vs 14% without CR; p = 0.002). Weight gain was predominant in patients who successfully quit smoking (42% vs 15.8%; p < 0.001). In addition, weight loss after one year was reported in 28.2% of persistent smokers compared to 20.6% of patients who stopped smoking. Reported stress level decreased in 34.9% of CR patients compared to 22.6% without CR (p < 0.001). Our AMIS Plus registry analysis shows that following CR participation, significantly more patients reported increased physical activity, smoke stop, dietary changes, weight loss and reduced stress at one year after an acute coronary syndrome. Maintenance of lifestyle changes is of utmost importance in secondary prevention after an acute coronary syndrome. A recent analysis of the Myocardial Ischaemia National Audit Project concluded that the adoption of optimal lifestyle care opportunities in high-risk NSTEMI patients were associated with a 25% long-term survival improvement at eight years.6 This finding is in line with our previous study, where we reported a significant reduction of crude one-year mortality in patients with CR.2 Increased physical activity was reported in 49% of CR patients compared to 20.6% without CR, while a reduction of physical activity after one year was present in significantly less CR patients than no-CR patients. The positive impact of CR persisted even after correction for age, gender and comorbidities, and confirms data from the OMEGA study.7 In the STABILITY study, 46% of subjects reported decreased physical activity after their first heart problem.8 Not attending a CR program was independently associated with lower physical activity after coronary artery disease diagnosis. In our study, CR was associated with a three-fold increase in physical activity, while age and female gender were negatively associated with increased physical activity one year after an acute coronary syndrome (ACS). Since physical activity is a cornerstone of healthy lifestyle in coronary artery disease patients, elderly women in particular should be in the focus during follow-up after an ACS. Significantly more CR patients reported having stopped smoking. After an ACS, a systematic and proactive strategy offering intensive smoking cessation interventions as in CR programs significantly increases the uptake of smoking cessation counselling and might increase smoking abstinence.9 Data about smoking cessation are available from the recent EUROASPIRE IV survey.10 The overall quit rate after a follow-up of 1.4 years was 51%, ranging from 29 to 73%. In our study population, smoking cessation was associated with increased physical activity after one year, independent of age, gender and CR participation. A total of 53% of all patients with CR participation reported healthy dietary changes after one year, while only 28.2% without CR did so. Dietary changes were even higher in patients with a BMI>30 (61.6% vs 35.9%). While weight loss was more present in CR participants, there was still an increase in body weight in 19.2% of CR patients. Interestingly, weight gain was predominant in patients who successfully quit smoking (42% vs 15.8%; p < 0.001). The strong interaction of weight gain and smoking cessation is a well-documented phenomenon. According to our data, there is the need for particular support and counselling of quitters with weight gain and to consider the referral of these patients to weight reduction programs. Therefore, our study demonstrates that participation in a comprehensive CR program after AMI in Switzerland results in beneficial lifestyle changes, such as increased physical activity and healthy eating, and a reduction of smoking, stress and body weight after a follow-up of one year.