Larry F. Hamm

Prediction of Long-Term Prognosis in 12 169 Men Referred for Cardiac Rehabilitation

Background—Predicting the risk of cardiac and all-cause death in patients with established coronary heart disease is important in counseling the individual and designing risk-stratified rehabilitation and secondary prevention programs. Cox proportional hazards and Kaplan-Meier survival curves were thus completed on initial assessment data obtained from patients referred to an outpatient cardiac rehabilitation center. Methods and Results—A single-center prospective observational design took peak cardiorespiratory exercise test data for 12 169 male rehabilitation candidates aged 55.0±9.6 years (7096 myocardial infarctions [MIs], 3077 coronary artery bypass grafts [CABGs], and 1996 documented cases of ischemic heart disease [IHD]). A follow-up of 4 to 29 years (median, 7.9) yielded 107 698 man-years of experience. Entry data were tested for associations with time to cardiac and all-cause death. We recorded 1336 cardiac deaths (953 MI, 225 CABG, and 158 IHD) and 2352 all-cause deaths. A powerful predictor of cardiac and all-cause mortality was measured peak oxygen intake (&OV0312;o2peak). For the overall sample, values of <15, 15 to 22, and >22 mL/kg per minute yielded respective multivariate adjusted hazard ratios of 1.00, 0.62, and 0.39 for cardiac and 1.00, 0.66, and 0.45 for all-cause deaths. For the separate diagnostic categories, apart from &OV0312;o2peak, the only other significant predictors of cardiac death common to all 3 were smoking and digoxin, and for all-cause death, age, smoking, digoxin, and diabetes. Conclusions—Exercise capacity, as determined by direct measurement of &OV0312;o2peak, exerts a major long-term influence on prognosis in men after MI, CABG, or IHD and can play a valuable role in risk stratification and counseling.

Increasing Referral and Participation Rates to Outpatient Cardiac Rehabilitation: The Valuable Role of Healthcare Professionals in the Inpatient and Home Health Settings A Science Advisory From the American Heart Association

Cardiovascular disease (CVD) continues to be the leading cause of morbidity and mortality in the United States and worldwide.1 In fact, the prevalence of CVD is on the rise as a function of increased longevity and the mounting effects of cardiac risk factors that typically accumulate over a lifetime. Outpatient cardiac rehabilitation (CR) programs offer a cost-effective, multidisciplinary, comprehensive approach to address these risk factors and to restore individuals to their optimal physiological, psychosocial, nutritional, and functional status.2–6 Thus, the benefits of CR extend well beyond the cardiovascular system, positively affecting an individuals overall health status. These benefits may be particularly important to certain CVD cohorts such as elderly patients who are more likely to present with greater functional limitations and frailty. Additionally, outpatient CR has been shown to dramatically reduce morbidity and mortality by nearly 25% compared with usual care.7,8 Despite the clear benefits of formal, supervised outpatient CR and exercise training programs, as well as strides in automatic referrals,9 current statistics continue to demonstrate that referral and participation rates of eligible patients remain alarmingly low,10–13 with participation particularly poor in rural areas and in eligible patients who have lower socioeconomic status, limited education, advanced age, and/or female sex.14,15 In addition, Gurewich et al16 reported several factors that are likely responsible for the poor referral rates to outpatient CR, which included “the degree of automation and assertiveness in securing referrals, the level of integration of CR within the hospital setting and physician community, the relationship to other CR facilities, and capacity constraints.” Given the continually poor referral and participation rate in outpatient CR despite increased efforts to reverse this trend, additional actions are required. This scientific advisory calls on the inpatient and home healthcare …

Core Competencies for Cardiac Rehabilitation/Secondary Prevention Professionals: 2010 Update: Position Statement of the American Association of Cardiovascular and Pulmonary Rehabilitation

Cardiac rehabilitation/secondary prevention (CR/SP) services are typically delivered by a multidisciplinary team of health care professionals. The American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) recognizes that to provide high-quality services, it is important for these health care professionals to possess certain core competencies. This update to the previous statement identifies 10 areas of core competencies for CR/SP health care professionals and identifies specific knowledge and skills for each core competency. These core competency areas are consistent with the current list of core components for CR/SP programs published by the AACVPR and the American Heart Association and include comprehensive cardiovascular patient assessment; management of blood pressure, lipids, diabetes, tobacco cessation, weight, and psychological issues; exercise training; and counseling for psychosocial, nutritional, and physical activity issues.

Safety and characteristics of exercise testing early after acute myocardial infarction

Five hundred and seventy physicians, researchers and clinicians (42% response) responded to a mailed questionnaire about the safety and nature of exercise testing conducted less than or equal to 4 weeks after acute myocardial infarction (AMI). Of 570 institutions, 193 reported that they routinely performed testing early after AMI and data were provided on 151,949 tests. A majority (111 or 58%) used a low-level testing protocol, 50 (26%) used symptom-limited testing and 32 (16%) used both types. Testing was routinely conducted less than or equal to 14 days after AMI by 147 (76%) respondents, whereas 46 (24%) tested 15 to 28 days after AMI. Thirty-three (17%) respondents used a standardized research protocol and 160 (83%) did not. There were 41 (0.03%) fatal, 141 (0.09%) major nonfatal and 2,124 (1.4%) other cardiac complications reported during testing. No difference in incidence of major complications was observed at centers using a clinical versus research protocol. Compared with clinic-based testing, hospital-based testing had an increased risk for all major (2.1) and nonfatal major complications (2.1). Although a symptom-limited protocol increased the overall risk for major cardiac complications by 1.9 times compared with a low-level protocol, the incidence of fatal complications during symptom-limited testing (0.03%) was quite low and this greater risk is of dubious clinical importance.

Cardiometabolic risk in community-dwelling persons with chronic spinal cord injury.

PURPOSE The purpose of this study was to describe cardiometabolic risk factors and risk clustering in people with spinal cord injury (SCI). METHODS This was a cross-sectional study of 121 subjects aged 18 to 73 years (mean, 37 ± 12 years) with chronic, motor complete SCI between C5 and T12. Assessments included demographic, social, and medical history; physical, anthropometric, and blood pressure assessments; fasting serum assays including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides, and hemoglobin A1c; calculated low-density lipoprotein cholesterol (LDL-C); and an oral glucose tolerance test. Framingham risk scores (FRSs) for each subject were calculated on the basis of Third National Cholesterol Education Program Adult Treatment Panel algorithm. RESULTS According to FRSs, 90.1%, 8.3%, and 1.7% were classified in the low-, medium-, and high-risk groups, respectively. The most prevalent cardiometabolic risk factors were overweight/obesity (74%), elevated LDL-C (64%), low HDL-C (53%), elevated systolic blood pressure (SBP, 33%), and elevated TC (30%). Stratification by level of injury demonstrated significant differences between paraplegic and tetraplegic participants in SBP (120 vs 99 mm Hg, P = .0001), 2-hour glucose (101.37 vs 137.93 mg/dL, P = .0001), and 2-hour insulin (47.45 vs 94.36 μIU/mL, P = .024). In addition, triglycerides, fasting insulin, body mass index, LDL-C, hemoglobin A1c, and insulin resistance were significantly associated with FRS. CONCLUSIONS Ten percent of young people with SCI are at moderate to high risk for long-term hard cardiac events. Overweight/obesity, LDL-C, HDL-C, SBP, and TC were the most prevalent risk factors. Carbohydrate metabolism is preferentially affected in persons suffering from tetraplegia, indicating a need for impairment-specific risk assessment.

Three 15-min Bouts of Moderate Postmeal Walking Significantly Improves 24-h Glycemic Control in Older People at Risk for Impaired Glucose Tolerance

OBJECTIVE The purpose of this study was to compare the effectiveness of three 15-min bouts of postmeal walking with 45 min of sustained walking on 24-h glycemic control in older persons at risk for glucose intolerance. RESEARCH DESIGN AND METHODS Inactive older (≥60 years of age) participants (N = 10) were recruited from the community and were nonsmoking, with a BMI <35 kg/m2 and a fasting blood glucose concentration between 105 and 125 mg dL−1. Participants completed three randomly ordered exercise protocols spaced 4 weeks apart. Each protocol comprised a 48-h stay in a whole-room calorimeter, with the first day serving as the control day. On the second day, participants engaged in either 1) postmeal walking for 15 min or 45 min of sustained walking performed at 2) 10:30 a.m. or 3) 4:30 p.m. All walking was on a treadmill at an absolute intensity of 3 METs. Interstitial glucose concentrations were determined over 48 h with a continuous glucose monitor. Substrate utilization was measured continuously by respiratory exchange (VCO2/VO2). RESULTS Both sustained morning walking (127 ± 23 vs. 118 ± 14 mg dL−1) and postmeal walking (129 ± 24 vs. 116 ± 13 mg dL−1) significantly improved 24-h glycemic control relative to the control day (P < 0.05). Moreover, postmeal walking was significantly (P < 0.01) more effective than 45 min of sustained morning or afternoon walking in lowering 3-h postdinner glucose between the control and experimental day. CONCLUSIONS Short, intermittent bouts of postmeal walking appear to be an effective way to control postprandial hyperglycemia in older people.

Automating activity-based interventions: The role of robotics

We have seen a continued growth of robotic devices being tested in neurorehabilitation settings over the last decade, with the primary goal to improve upper- and lower-motor function in individuals following stroke, spinal cord injury, and other neurological conditions. Interestingly, few studies have investigated the use of these devices in improving the overall health and well-being of these individuals despite the capability of robotic devices to deliver intensive time-unlimited therapy. In this article, we discuss the use of robotic devices in delivering intense, activity-based therapies that may have significant exercise benefits. We also present preliminary data from studies that investigated the metabolic and cardiac responses during and after 6 months of lower-limb robotic training. Finally, we speculate on the future of robotics and how these devices will affect rehabilitation interventions.

The Toronto Cardiac Rehabilitation and Secondary Prevention Program: 1968 into the new millennium.

Given our approach to the cardiac rehabilitation process, which is reflected in the program structure and services and our high patient volume, this program model is effective for us. The model permits us to treat relatively large number of patients with relatively small numbers of staff. On average, a patient attends 32 supervised exercise sessions at the Centre over the course of 12 months. This is actually fewer supervised sessions than the popular model of 3 times per week for 12 weeks. However, the 12-month program provides an additional 9 months to work with patients on heart-healthy lifestyle modifications. At the same time, we realize our model is not the model of choice for all people in all settings for a variety of reasons. We trust that some elements of our program may be of interest and beneficial to some readers. Undoubtedly, the program will continue to evolve and develop into the future. Currently, we are conducting a cardiac rehabilitation outcomes study in an effort to determine the appropriate duration of cardiac rehabilitation to achieve optimal physiological, psychological, and cost benefits for patients. This study involves more than 700 patients and the results are intended to help us further refine the program structure and selected program elements. As the new millennium approaches, healthcare system reforms and continuing changes in the delivery of medical care to cardiac patients present opportunities, challenges, and some uncertainties for cardiac rehabilitation. To continue our services to patients and the medical community, cardiac rehabilitation programs will need to identify and develop even more innovative and effective concepts in response to ever-changing local, regional, and national issues.

Timeline for Peak Improvements During 52 Weeks of Outpatient Cardiac Rehabilitation

PURPOSE Cardiac rehabilitation is an integral component of comprehensive care for patients with coronary heart disease. Although the typical programmatic delivery of outpatient cardiac rehabilitation services often involves 36 sessions over 12 weeks, that format is based more on historical practice than on outcome data. This study aimed to determine the point at which during 52 weeks of outpatient cardiac rehabilitation, patients achieved peak values for selected outcomes, and whether the number of supervised exercise sessions had any effect on these outcomes. METHODS In this study, 623 male patients with coronary heart disease admitted to an outpatient cardiac rehabilitation program were randomized to one of two 52-week program formats. One format (CR1) used one supervised exercise session per week over 52 weeks, and the second format (CR2) used weekly supervised sessions for 26 weeks followed by one supervised session per month for the remaining 26 weeks. Both formats used four unsupervised, documented exercise sessions per week. Selected clinical, physiologic, and psychological variables were measured at baseline, then at 4, 12, 26, 38, and 52 weeks. The program costs for both the CR1 and CR2 formats were calculated from known expenses. RESULTS Because there were no significant intercohort differences between CR1 and CR2 and no significant interaction (time x group), data from the two cohorts were pooled for statistical analysis. Peak oxygen intake (VO(2peak)) significantly increased by 4.4 mL/kg per minute at 38 weeks, and the greatest percentage of patients (30.1%) also achieved their highest VO(2peak) at this time. The largest gain in Medical Outcomes Survey Short Form 36 role physical scores was from baseline to 38 weeks (52.4 versus 85.2), and the highest percentage of patients (72%) with role physical scores in the excellent category occurred at 38 weeks. Clinical depression at baseline (Beck Depression Inventory score > 10) had no significant effect on the dropout rate or the gain in VO(2peak) with exercise training. Program costs for these alternative formats of service were similar to the cost for a standard program format of 36 sessions. CONCLUSIONS Patients achieved their highest functional capacity after 38 weeks of outpatient cardiac rehabilitation using a program format of only 29 to 38 supervised exercise sessions. The results of this study show that an outpatient cardiac rehabilitation program combining supervised with unsupervised exercise sessions and continuing for 38 weeks results in the greatest improvement in these selected outcomes.

Cardiometabolic Risk Clustering in Spinal Cord Injury: Results of Exploratory Factor Analysis

BACKGROUND Evidence suggests an elevated prevalence of cardiometabolic risks among persons with spinal cord injury (SCI); however, the unique clustering of risk factors in this population has not been fully explored. OBJECTIVE The purpose of this study was to describe unique clustering of cardiometabolic risk factors differentiated by level of injury. METHODS One hundred twenty-one subjects (mean 37 ± 12 years; range, 18-73) with chronic C5 to T12 motor complete SCI were studied. Assessments included medical histories, anthropometrics and blood pressure, and fasting serum lipids, glucose, insulin, and hemoglobin A1c (HbA1c). RESULTS The most common cardiometabolic risk factors were overweight/obesity, high levels of low-density lipoprotein (LDL-C), and low levels of high-density lipoprotein (HDL-C). Risk clustering was found in 76.9% of the population. Exploratory principal component factor analysis using varimax rotation revealed a 3-factor model in persons with paraplegia (65.4% variance) and a 4-factor solution in persons with tetraplegia (73.3% variance). The differences between groups were emphasized by the varied composition of the extracted factors: Lipid Profile A (total cholesterol [TC] and LDL-C), Body Mass-Hypertension Profile (body mass index [BMI], systolic blood pressure [SBP], and fasting insulin [FI]); Glycemic Profile (fasting glucose and HbA1c), and Lipid Profile B (TG and HDL-C). BMI and SBP formed a separate factor only in persons with tetraplegia. CONCLUSIONS Although the majority of the population with SCI has risk clustering, the composition of the risk clusters may be dependent on level of injury, based on a factor analysis group comparison. This is clinically plausible and relevant as tetraplegics tend to be hypo- to normotensive and more sedentary, resulting in lower HDL-C and a greater propensity toward impaired carbohydrate metabolism.