An evaluation of the role of the exercise training dose for changes in exercise capacity following a standard cardiac rehabilitation program.

BACKGROUND: To retrospectively characterize and compare the dose of exercise training (ET) within a large cohort of patients demonstrating different levels of improvement in exercise capacity following a cardiac rehabilitation (CR) program. METHODS: A total of 2310 patients who completed a 12-week, center-based, guidelines-informed CR program between January 2018 and December 2019 were included in the analysis. Peak metabolic equivalents (METpeak) were determined pre- and post-CR during which total duration (ET time) and intensity [percent of heart rate peak (%HRpeak)] of supervised ET were also obtained. Training responsiveness was quantified on the basis of changes in METpeak from pre- to post-CR. A cluster analysis was performed to identity clusters demonstrating discrete levels of responsiveness (i.e., negative, low, moderate, high, and very-high). These were compared for several baseline and ET-derived variables which were also included in a multivariable linear regression model. RESULTS: At pre-CR, baseline METpeak was progressively lower with greater training responsiveness (F(4,2305) = 44.2, P < 0.01, η2p = 0.71). Likewise, average training duration (F(4,2305) = 10.7 P < 0.01, η2p = 0.02) and %HRpeak (F(4,2305) = 25.1 P < 0.01, η2p = 0.042) quantified during onsite ET sessions were progressively greater with greater training responsiveness. The multivariable linear regression model confirmed that baseline METpeak, training duration and intensity during ET, BMI, and age (P < 0.001) were significant predictors of METpeak post-CR. CONCLUSIONS: Along with baseline METpeak, delta BMI, and age, the dose of ET (i.e., training duration and intensity) predicts METpeak at the conclusion of CR. A re-evaluation of current approaches for exercise intensity prescription is recommended to extend the benefits of completing CR to all patients.

Long-Term Maintenance of Cardiorespiratory Fitness Gains After Cardiac Rehabilitation Reduces Mortality Risk in Patients With Multimorbidity.

PURPOSE: The objective of this study was to characterize the impact of multimorbidity and cardiorespiratory fitness (CRF) on mortality in patients completing cardiac rehabilitation (CR). METHODS: This cohort study included data from patients with a history of cardiovascular disease (CVD) completing a 12-wk CR program between January 1996 and March 2016, with follow-up through March 2017. Patients were stratified by the presence of multimorbidity, which was defined as having a diagnosis of ≥2 noncommunicable diseases (NCDs). Cox regression analyses were used to evaluate the effects of multimorbidity and CRF on mortality in patients completing CR. Symptom-limited exercise tests were completed at baseline, immediately following CR (12 wk), with a subgroup completing another test at 1-yr follow-up. Peak metabolic equivalents (METs) were determined from treadmill speed and grade. RESULTS: Of the 8320 patients (61 ± 10 yr, 82% male) included in the analyses, 5713 (69%) patients only had CVD diagnosis, 2232 (27%) had CVD+1 NCD, and 375 (4%) had CVD+≥2 NCDs. Peak METs at baseline (7.8 ± 2.0, 6.9 ± 2.0, 6.1 ± 1.9 METs), change in peak METs immediately following CR (0.98 ± 0.98, 0.83 ± 0.95, 0.76 ± 0.95 METs), and change in peak METs 1 yr after CR (0.98 ± 1.27, 0.75 ± 1.17, 0.36 ± 1.24 METs) were different ( P < .001) among the subgroups. Peak METs at 12 wk and the presence of coexisting conditions were each predictors ( P < .001) of mortality. Improvements in CRF by ≥0.5 METS from baseline to 1-yr follow-up among patients with or without multimorbidity were associated with lower mortality rates. CONCLUSION: Increasing CRF by ≥0.5 METs improves survival regardless of multimorbidity status.

Prediction of Mortality in Coronary Artery Disease: Role of Machine Learning and Maximal Exercise Capacity.

OBJECTIVE: To develop a prediction model for survival of patients with coronary artery disease (CAD) using health conditions beyond cardiovascular risk factors, including maximal exercise capacity, through the application of machine learning (ML) techniques. METHODS: Analysis of data from a retrospective cohort linking clinical, administrative, and vital status databases from 1995 to 2016 was performed. Inclusion criteria were age 18 years or older, diagnosis of CAD, referral to a cardiac rehabilitation program, and available baseline exercise test results. Primary outcome was death from any cause. Feature selection was performed using supervised and unsupervised ML techniques. The final prognostic model used the survival tree (ST) algorithm. RESULTS: From the cohort of 13,362 patients (60±11 years; 2400 [18%] women), 1577 died during a median follow-up of 8 years (interquartile range, 4 to 13 years), with an estimated survival of 67% up to 21 years. Feature selection revealed age and peak metabolic equivalents (METs) as the features with the greatest importance for mortality prediction. Using these 2 features, the ST generated a long-term prediction with a C-index of 0.729 by splitting patients in 8 clusters with different survival probabilities (P<.001). The ST root node was split by peak METs of 6.15 or less or more than 6.15, and each patient's subgroup was further split by age or other peak METs cut points. CONCLUSION: Applying ML techniques, age and maximal exercise capacity accurately predict mortality in patients with CAD and outperform variables commonly used for decision-making in clinical practice. A novel and simple prognostic model was established, and maximal exercise capacity was further suggested to be one of the most powerful predictors of mortality in CAD.

Current Activities Centered on Healthy Living and Recommendations for the Future: A Position Statement from the HL-PIVOT Network.

We continue to increase our cognizance and recognition of the importance of healthy living (HL) behaviors and HL medicine (HLM) to prevent and treat chronic disease. The continually unfolding events precipitated by the coronavirus disease 2019 (COVID-19) pandemic have further highlighted the importance of HL behaviors, as indicated by the characteristics of those who have been hospitalized and died from this viral infection. There has already been recognition that leading a healthy lifestyle, prior to the COVID-19 pandemic, may have a substantial protective effect in those who become infected with the virus. Now more than ever, HL behaviors and HLM are essential and must be promoted with a renewed vigor across the globe. In response to the rapidly evolving world since the beginning of the COVID-19 pandemic, and the clear need to change lifestyle behaviors to promote human resilience and quality of life, the HL for Pandemic Event Protection (HL-PIVOT) network was established. The 4 major areas of focus for the network are: (1) knowledge discovery and dissemination; (2) education; (3) policy; (4) implementation. This HL-PIVOT network position statement provides a current synopsis of the major focus areas of the network, including leading research in the field of HL behaviors and HLM, examples of best practices in education, policy, and implementation, and recommendations for the future.

Identification of Patients With COPD in a Cardiac Rehabilitation Setting: THE COnCuR STUDY.

PURPOSE: To examine the feasibility of screening for chronic obstructive pulmonary disease (COPD) in an outpatient cardiac rehabilitation (CR) setting and to evaluate the detection rate of COPD using a targeted screening protocol. METHODS: A total of 95 patients (62.5 ± 10.0 yr; men, n = 77), >40-yr old with a history of smoking were included in the study sample. Each participant answered the 5-item Canadian Lung Health Test (CLHT) questionnaire assessing symptoms such as coughing, phlegm, wheezing, shortness of breath, and frequent colds. Endorsing ≥1 item was indicative of potential COPD and warranted pulmonary function testing (PFT) and/or spirometry to diagnose or rule out COPD. RESULTS: The CLHT questionnaire identified 44 patients at risk for COPD, with an average of 1.9 ± 1.2 items endorsed. Of the patients who underwent PFT, 6 new cases of mild COPD were diagnosed, resulting in a true positive rate with CLHT screening of 19% and a false-positive rate of 81%. CONCLUSIONS: Implementing the CLHT to patients referred to CR correctly identified COPD in <20% of cases. Using the CLHT to screen for COPD prior to starting CR may not be optimal, due to disparities between true- and false-positive rates.

Cardiometabolic responses to cardiac rehabilitation in people with and without diabetes.

BACKGROUND: Type 2 diabetes and cardiometabolic comorbidities manifesting as the metabolic syndrome (MetS) are highly prevalent in coronary heart disease (CHD) patients attending cardiac rehabilitation (CR). The study aimed to determine the prevalence of cardiometabolic derangements and MetS, and compare post-CR clinical responses in a large cohort of CHD patients with and without diabetes. METHODS: Analyses were conducted on 3953 CHD patients [age: 61.1 ±â€¯10.5 years; 741 (18.7%) with diabetes] that completed a representative 12-week CR program. A propensity model was used to match patients with diabetes (n = 731) to those without diabetes (n = 731) on baseline and clinical characteristics. RESULTS: Diabetic patients experienced smaller improvements in metabolic parameters after completing CR, including abdominal obesity, and lipid profiles (all P ≤ .002), compared to non-diabetic patients. For both groups, there were similar improvement rates in peak metabolic equivalents ([METs]; P < .001); however, peak METs remained lower at 12-weeks in patients with diabetes than without diabetes. At baseline, the combined prevalence of insulin resistance (IR) and diabetes was 57.3%, whereas IR was present in 48.2% of non-diabetic patients, of which rates were reduced to 48.2% and 32.8% after CR, respectively. Accordingly, MetS prevalence decreased from 25.5% to 22.3% in diabetic versus 20.0% to 13.4% in non-diabetic patients (all P ≤ .004). CONCLUSIONS: Completing CR appears to provide comprehensive risk reduction in cardio-metabolic parameters associated with diabetes and MetS; however, CHD patients with diabetes may require additional and more aggressive attention towards all MetS criteria over the course of CR in order to prevent future cardiovascular events.

Integrating Science, Practice, and Mentorship in Cardiac Rehabilitation: THE INAUGURAL TOTALCARDIOLOGY® RESEARCH NETWORK RETREAT.

The evidence base supporting cardiac rehabilitation is substantial and overwhelmingly supports its utilization for all qualified patients. However, important lines of inquiry remain and require attention. This commentary provides a model for cardiac rehabilitation centers that provide patient care to meaningfully contribute to our scientific understanding of this lifestyle intervention.

Optimizing Value From Cardiac Rehabilitation: A Cost-Utility Analysis Comparing Age, Sex, and Clinical Subgroups.

OBJECTIVE: To assess the cost utility of a center-based outpatient cardiac rehabilitation program compared with no program within patient subgroups on the basis of age, sex, and clinical presentation (acute coronary syndrome [ACS] or non-ACS). METHODS: We performed a cost-utility analysis from a health system payer perspective to compare cardiac rehabilitation with no cardiac rehabilitation for patients who had a cardiac catheterization. The Markov model was stratified by clinical presentation, age, and sex. Clinical, quality-of-life, and cost data were provided by the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease and TotalCardiology. RESULTS: The incremental cost per quality-adjusted life-year (QALY) gained for cardiac rehabilitation varies by subgroup, from $18,101 per QALY gained to $104,518 per QALY gained. There is uncertainty in the estimates due to uncertainty in the clinical effectiveness of cardiac rehabilitation. Overall, the probabilistic sensitivity analysis found that 75% of the time participation in cardiac rehabilitation is more expensive but more effective than not participating in cardiac rehabilitation. CONCLUSION: The cost-effectiveness of cardiac rehabilitation varies depending on patient characteristics. The current analysis indicates that cardiac rehabilitation is most cost effective for those with an ACS and those who are at higher risk for subsequent cardiac events. The findings of the current study provide insight into who may benefit most from cardiac rehabilitation, with important implications for patient referral patterns.

Cardiac rehabilitation completion is associated with reduced mortality in patients with diabetes and coronary artery disease.

AIMS: Cardiac rehabilitation (CR) reduces the risks of mortality and hospitalisation in patients with coronary artery disease and without diabetes. It is unknown whether patients with diabetes obtain the same benefits from CR. METHODS: We retrospectively examined patients referred to a 12 week CR programme between 1996 and 2010. Associations between CR completion vs non-completion and death, hospitalisation rate and cardiac hospitalisation rate were assessed by survival analysis. RESULTS: Over the study period, 13,158 participants were referred to CR (mean ± SD, age 59.9 ± 11.1 years, 28.9% female, 2,956 [22.5%] with diabetes). Patients with diabetes were less likely to complete CR than those without diabetes (41% vs 56%, p < .0001). Over a median follow-up of 6.6 years, there were 379 deaths in patients with diabetes vs 941 deaths among those without diabetes (12.8% vs 8.9%). Of the non-completers, patients with diabetes had a higher mortality rate compared with those without diabetes (17.7% vs 11.3%). In patients who completed CR, mortality was lower: 11.1% in patients with diabetes vs 7.0% in those without diabetes. In patients with diabetes, CR completion was associated with reduced mortality (HR 0.46 [95% CI 0.37, 0.56]), reduced hospitalisation (HR 0.86 [95% CI 0.76, 0.96]) and reduced cardiac hospitalisation (HR 0.67 [95% CI 0.54, 0.84]). The protective associations were similar to those of patients without diabetes. In multivariable adjusted analyses, all of these associations remained significant. CONCLUSIONS: Patients with diabetes were less likely to complete CR than those without diabetes. However, patients with diabetes who completed CR derived similar apparent reductions in mortality and hospitalisation to patients without diabetes.

Cardiac rehabilitation referral, attendance and mortality in women.

BACKGROUND: Cardiac rehabilitation (CR) reduces mortality in women and men with coronary artery disease (CAD). The objective of this study was to examine sex differences in long-term mortality, based on CR referral rates and attendance patterns in a large CAD population. DESIGN: This is a retrospective cohort study. METHODS: The Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease (APPROACH) and Cardiac Wellness Institute of Calgary (CWIC) databases were used to obtain information on all patients. Rates of referral to and attendance at CR were compared by sex. Logistic regression models were constructed to assess whether sex predicted CR referral or completion. The association between referral, completion, and survival was assessed by sex using Cox proportional hazard models. RESULTS: 25,958 subjects (6374-24.6%-were women) with at least one vessel CAD were included. Females experienced reduced rates of CR referral (31.1% vs 42.2%, p < 0.0001) and completion (50.1 vs 60.4%, p < 0.0001). Adjusting for demographic and clinical characteristics, relative to men, CR referral was significantly lower in women (adjusted odds ratio (OR) 0.74, 95% CI 0.69, 0.79) as was CR completion (adjusted OR 0.73, 95% CI 0.66, 0.81). Women completing CR experienced the greatest reduction in mortality (HR 0.36, 95% CI 0.28, 0.45) with a relative benefit greater than men (HR 0.51, 95% CI 0.46, 0.56). CONCLUSION: This is the first large cohort study to demonstrate that referral to and attendance at CR is associated with a significant mortality reduction in women, comparatively better than that in men.

Patients with diabetes in cardiac rehabilitation: attendance and exercise capacity.

PURPOSE: Diabetes increases mortality after myocardial infarction, but participation in cardiac rehabilitation (CR) reduces this risk. Our objectives were to examine whether attendance at CR and changes in cardiorespiratory fitness differed according to diabetic status and sex. METHODS: Retrospective cohort study of patients referred for CR in Calgary between 1996 and 2010. Cardiorespiratory fitness in metabolic equivalents (METs) was estimated by maximal exercise testing at baseline, at the end of the 12-wk CR program, and 1-yr after CR. RESULTS: Among 7036 nondiabetic and 1546 diabetic patients who started, 84.9% of nondiabetic versus 79.5% of diabetic patients completed CR (P < 0.0001). The difference between diabetic and nondiabetic patients was greater in women (81.7% vs 72.1%, P < 0.0001) than that in men (86.0% vs 82.5%, P = 0.004). Patients without diabetes were more likely to return for the 1-yr assessment (53.7% vs 42.7%, P < 0.0001), and nondiabetic women were more likely than diabetic women to attend the 1-yr follow-up (44.3% vs 31.7%, P < 0.0001). Change in cardiorespiratory fitness from baseline to 12 wk was +1.0 METs in nondiabetic men, +0.9 METS in diabetic men, +0.9 METs in nondiabetic women, and +0.7 METs in diabetic women (within-group change; P = 0.0009). Changes in cardiorespiratory fitness at 1 yr compared with baseline were +0.9, +0.6, +0.9, and +0.5 METS, respectively (within-group change, P = 0.0001). CONCLUSIONS: Patients with diabetes, especially females, were less likely than patients without diabetes to complete CR and attend follow-up. Among patients who attended 1-yr follow-up, changes in cardiorespiratory fitness were not as well maintained in diabetic patients as in nondiabetic patients. Identifying barriers and targeting CR adherence interventions to patients with diabetes may help improve outcomes.

Cardiovascular fitness and mortality after contemporary cardiac rehabilitation.

OBJECTIVE: To assess the association between cardiorespiratory fitness (CRF) and outcomes in a cardiac rehabilitation (CR) cohort. PATIENTS AND METHODS: We conducted a retrospective study of 5641 patients (4282 men [76%] and 1359 women [24%]; mean ± SD age, 60.0±10.3 years) with coronary artery disease who participated in CR between July 1, 1996, and February 28, 2009. Based on peak metabolic equivalents (METs), patients were classified as low fitness (LFit) (<5 METs), moderate fitness (5-8 METs), or high fitness (>8 METs). RESULTS: Baseline fitness predicted long-term mortality: relative to the LFit group, patients with moderate fitness had an adjusted hazard ratio of 0.54 (95% CI, 0.42-0.69), and those with high fitness a hazard ratio of 0.32 (95% CI, 0.24-0.44). Improvement in CRF at 12 weeks was associated with decreased overall mortality, with a 13% point reduction with each MET increase (P<.001) and a 30% point reduction in those who started with LFit. At 1 year, each MET increase in CRF was associated with a 25% point reduction in overall mortality in the whole group (P<.001). CONCLUSION: In this study of contemporary CR patients, higher baseline fitness predicted lower mortality. The novel finding was that improvement in fitness during a CR program and improvements that persisted at 1 year were also associated with decreased mortality, most strongly in patients who start with LFit.

Cardiac rehabilitation attendance and outcomes in coronary artery disease patients.

BACKGROUND: Cardiac rehabilitation (CR) is an efficacious yet underused treatment for patients with coronary artery disease. The objective of this study was to determine the association between CR completion and mortality and resource use. METHODS AND RESULTS: We conducted a prospective cohort study of 5886 subjects (20.8% female; mean age, 60.6 years) who had undergone angiography and were referred for CR in Calgary, AB, Canada, between 1996 and 2009. Outcomes of interest included freedom from emergency room visits, hospitalization, and survival in CR completers versus noncompleters, adjusted for clinical covariates, treatment strategy, and coronary anatomy. Hazard ratios for events for CR completers versus noncompleters were also constructed. A propensity model was used to match completers to noncompleters on baseline characteristics, and each outcome was compared between propensity-matched groups. Of the subjects referred for CR, 2900 (49.3%) completed the program, and an additional 554 subjects started but did not complete CR. CR completion was associated with a lower risk of death, with an adjusted hazard ratio of 0.59 (95% confidence interval, 0.49-0.70). CR completion was also associated with a decreased risk of all-cause hospitalization (adjusted hazard ratio, 0.77; 95% confidence interval, 0.71-0.84) and cardiac hospitalization (adjusted hazard ratio, 0.68; 95% confidence interval, 0.55-0.83) but not with emergency room visits. Propensity-matched analysis demonstrated a persistent association between CR completion and reduced mortality. CONCLUSIONS: Among those coronary artery disease patients referred, CR completion is associated with improved survival and decreased hospitalization. There is a need to explore reasons for nonattendance and to test interventions to improve attendance after referral.

Obesity negatively impacts aerobic capacity improvements both acutely and 1-year following cardiac rehabilitation.

Cardiac rehabilitation (CR) produces a host of health benefits related to modifiable cardiovascular risk factors. The purpose of the present investigation was to determine the influence of body weight, assessed through BMI, on acute and long-term improvements in aerobic capacity following completion of CR. Three thousand nine hundred and ninety seven subjects with coronary artery disease (CAD) participated in a 12-week multidisciplinary CR program. Subjects underwent an exercise test to determine peak estimated metabolic equivalents (eMETs) and BMI assessment at baseline, immediately following CR completion and at 1-year follow-up. Normal weight subjects at 1-year follow-up demonstrated the greatest improvement in aerobic fitness and best retention of those gains (gain in peak METs: 0.95 ± 1.1, P < 0.001). Although the improvement was significant (P < 0.001), subjects who were initially classified as obese had the lowest aerobic capacity and poorest retention in CR fitness gains at 1-year follow-up (gain in peak eMETs: 0.69 ± 1.2). Subjects initially classified as overweight by BMI had a peak eMET improvement that was also significantly better (P < 0.05) than obese subjects at 1-year follow-up (gain in peak eMETs: 0.82 ± 1.1). Significant fitness gains, one of the primary beneficial outcomes of CR, can be obtained by all subjects irrespective of BMI classification. However, obese patients have poorer baseline fitness and are more likely to "give back" fitness gains in the long term. Obese CAD patients may therefore benefit from additional interventions to enhance the positive adaptations facilitated by CR.

The independent effect of traditional cardiac rehabilitation and the LEARN program on weight loss: a comparative analysis.

INTRODUCTION: Despite its numerous other benefits, cardiac rehabilitation (CR) has not consistently proven to be an effective, although much needed, intervention for weight loss in the cardiovascular disease (CVD) population. Comparatively, the LEARN (Lifestyle, Exercise, Attitudes, Relationships, Nutrition) program appears to be an effective intervention for weight loss. The purpose of the present investigation was to compare changes in body weight in a CVD cohort consecutively participating in traditional CR and the LEARN program. METHODS: Forty-four patients diagnosed with CVD (22 men/22 women) participated in a 12-week multidisciplinary CR program. All patients successfully completed the LEARN program following CR. Body mass index (BMI) and body weight were recorded immediately prior to and following both CR and LEARN. RESULTS: The peak metabolic equivalents were significantly higher following CR (7.3 ± 1.6 vs 8.5 ± 1.6, P < .001), while body weight (203.5 ± 32.6 vs 201.8 ± 32.5 lbs, P > .10) and BMI (32.1 ± 4.0 vs 31.8 ± 3.9 kg/m, P > .05) were unchanged. All subjects then successfully completed the LEARN program, participating in an average of 10 sessions. There was a significant reduction in body weight (203.3 ± 30.7 vs 190.1 ± 30.4 lbs, P < .001) and BMI (32.0 ± 3.9 vs 29.5 ± 3.8 kg/m, P < .001) following the LEARN program. DISCUSSION: Our results support the independent value of the LEARN program in eliciting weight loss for CR patients. Clinicians delivering CR services should consider integrating a focused weight loss program, such as LEARN, into their usual CR programs.

AGREEing on Canadian cardiovascular clinical practice guidelines.

The use of clinical practice guidelines (CPGs), particularly the routine implementation of evidence-based cardiovascular health maintenance and disease management recommendations, affords both expert and nonexpert practitioners the opportunity to achieve better, and at least theoretically similar, patient outcomes. However, health care practitioners are often stymied in their efforts to follow even well-researched and well-written CPGs as a consequence of contradictory information. The purposeful integration and harmonization of Canadian cardiovascular CPGs, regardless of their specific risk factor or clinical management focus, is critical to their widespread acceptance and implementation. This level of cooperation and coordination among CPG groups and organizations would help to ensure that their clinical practice roadmaps (ie, best practice recommendations) contain clear, concise and complementary, rather than contradictory, patient care information. Similarly, the application of specific tools intended to improve the quality of CPGs, such as the Appraisal of Guidelines for Research and Evaluation (AGREE) assessment tool, may also lead to improvements in CPG quality and potentially enhance their acceptance and implementation.