Note: CABG = coronary artery bypass graft surgery; CHD = coronary heart disease; ECG = electrocardiographic; MI myocardial infarction; MMPI = Minnesota Multiphasic Personality = Inventory. Studies of exercise rehabilitation as the sole intervention are confounded by the consequences of group interaction, formation of social support networks, peer and professional support, counseling and guidance, all of which may affect depression, anxiety, and self-confidence. Social Adjustment and Functioning RECOMMENDATION Cardiac rehabilitation exercise training improves social adjustment and functioning. Exercise training is recommended to improve these social outcomes. Scientific Evidence (Strength of Evidence = B) Six reports in the scientific literature addressed various measures of social adjustment and functioning in patients following cardiac rehabilitation exercise training. These measures include the Sickness Impact Profile scores, leisure and social questionnaire scores, social activity scores, and scores of satisfaction with work and social satisfaction. Two studies were randomized controlled trials, one was a nonrandomized controlled study, and three were observational reports. Both randomized controlled trials reported favorable outcomes in rehabilitation patients compared with control patients. 103,243 In one trial, the benefit was noted at the 3-month followup but not at the 6-month followup.103 The second randomized controlled trial documented benefit at the 1-year followup.243 The nonrandomized controlled study did not report statistically significant improvements in measures of social and work satisfaction in patients with diminished left ventricular ejection fraction (less than 40 percent) but no symptoms of heart failure.78 One observational study of 3 months of exercise training as the sole intervention in patients following myocardial infarction or CABG reported improvement in social functioning at 4 months. 171 Two additional observational studies reported improvement in social functioning following cardiac rehabilitation exercise training,242,244 Conclusions The social benefits, established by randomized controlled trials, are a favorable result of participation in exercise and multifactorial cardiac rehabilitation. Only two reports, and only one controlled trial, involved patients over 65 years of age, for whom social outcomes may differ from those in most of the patients studied, who were younger than age 60-65. Only two controlled trials included women, and in these, women were 15 and 17 percent of the patients; no social outcomes were reported by gender. Only one controlled trial involved multifactorial rehabilitation; all others reported social outcomes associated with exercise training as the sole intervention. More research is needed to evaluate various measures of social adjustment or functioning as an outcome of multifactorial cardiac rehabilitation. Return to Work RECOMMENDATION Cardiac rehabilitation exercise training exerts less influence on rates of return to work than many nonexercise variables including employer attitudes, prior employment status, economic incentives, and the like. Exercise training as a sole intervention is not recommended to facilitate return to work. Scientific Evidence (Strength of Evidence = A). The scientific evidence relating to return to work as an outcome of exercise-based cardiac rehabilitation was derived from 28 reports. Ten were randomized controlled trials, nine were nonrandomized controlled studies, and nine were observational reports. One study evaluated the effect of exercise testing and physician counseling following uncomplicated myocardial infarction on return to work. Higher rates of return to work were evident in 2 of the 10 randomized controlled trials, both of which were carried out in Europe, where the social structure of rehabilitation may greatly differ from that in the United States;51,58 increased maintenance of work at 6 months was also noted in one of these studies.58 Eight randomized controlled trials documented no difference in rates of return to work for rehabilitation patients compared with control patients.9-11,55,57,153,219,243 No study demonstrated an adverse effect of exercise rehabilitation on return to work. One randomized controlled trial reported the value of exercise testing followed by physician counseling based on exercise test results on return to work after myocardial infarction: A statistically significant earlier return to work, in both manual and nonmanual workers, occurred in counseled patients compared with control patients.56 Seven of the nine nonrandomized controlled studies reported a significantly greater return to work, with higher rates reported in exercise rehabilitation populations than in control populations.40,78,167,169,221,245,246 Eight of the nine observational studies reported a favorable effect of exercise rehabilitation on work resumption.81,84,196,205,242,244,247,248 One report of the effects of lower versus higher levels of exercise training on rates of return to work found no differences between the two exercise-training regimens.159 Virtually all patients studied were younger than 65 years of age, with the mean age often between 50 and 59. Women were infrequently represented, accounting for 12-25 percent of the study populations when enrolled; no return to work data were provided by gender. These features limit the generalizability of results. The results did not appear to differ in populations of patients with myocardial infarction, CABG, or PTCA. Both studies of patients with a decreased left ventricular ejection fraction78,81 described a favorable return to work, as did the observational report of patients after cardiac transplantation.84 One randomized controlled trial55 defined predictors of failure to return to work as being unemployed at the time of infarction, an unstable work history, the patient's opinion that the job would not be available at recovery, family and social instability, later age of having started smoking, high anxiety and depression scores on the MMPI, lower educational level, and unskilled prior occupation. One randomized controlled trial243 defined baseline anxiety as a significant negative influence on return to work, as well as older age, dyspnea at myocardial infarction, and low leisure and social activity scores at baseline. In another randomized controlled trial,40 low-risk status following infarction was associated with an earlier return to work than was high-risk status. In a nonrandomized controlled trial,162 older age and prior myocardial infarction resulted in a decreased return to work, as did cigarette smoking, hypertension, and extended sick leave prior to CABG. In observational studies, higher life-satisfaction scores 244 predicted increase in return to work, and lower baseline functional capacity248 predicted failure to resume work. No study examined the relationships among rehabilitation exercise training, the type of work or physical demands of employment, and the rate of return to work. No study identified specific vocational interventions. Conclusions Assessment of return to work as a result of exercise training must be considered within the context of social and political variables that are typically not addressed in the studies of cardiac rehabilitation. These variables include the political system and social policies of the country in which cardiac rehabilitation occurs. Additional factors include employment statistics for the years of the study for U.S. studies, economic incentives or disincentives for patients to return to work, non-patient-related factors such as employer attitudes, and the preillness employment status of the patient, among others. A number of studies failed to compare outcomes in patients employed or not employed at the time of the cardiac event and often, for unemployed patients, did not define the duration of preillness or prerehabilitation unemployment-variables known to influence return to work. Generalizability may further be limited in that patients who are study volunteers may be more likely to return to work. Finally, return to work as a measure of outcome of exercise-based cardiac rehabilitation may not be appropriate unless formal vocational rehabilitation services are provided to patients as part of the rehabilitative process. Morbidity and Safety Issues RECOMMENDATION Cardiac rehabilitation exercise training does not change the rates of nonfatal reinfarction. The safety of exercise rehabilitation is well established; rates of infarction and cardiovascular complications during exercise training are very low. Scientific Evidence (Strength of Evidence = A). Evidence pertaining to cardiovascular morbidity related to exercise rehabilitation was derived from 42 scientific reports, including 15 randomized controlled trials, 14 nonrandomized controlled studies, and 13 observational reports. In addition, two large questionnaire surveys of cardiac rehabilitation programs, which specifically assessed morbidity rates, were included in the review. All 15 randomized controlled trials, including 10 involving only exercise training and 5 multifactorial studies, reported no statistically significant differences in the rates of reinfarction for rehabilitation and control patients.9,10,12,14–17,39,49,50,52,153,159,219,249 These studies are described in Table 7. Seven of the 14 nonrandomized controlled studies reported reinfarction rates. Six of these seven studies involved multifactorial rehabilitation, and two of them reported a significant reduction in reinfarction rates in rehabilitation patients compared with control patients: p = .02,169 p < .001.40 Reinfarction rates were reduced in myocardial infarction patients younger than 65 years at the 1- to 5-year followups but not at the 6- to 10-year followups. The other four multifactorial nonrandomized controlled studies did not report statistically significant reductions in reinfarction rates. 20,28,250,251 One nonrandomized controlled study with exercise training as the sole rehabilitation intervention reported significant reduction in reinfarction rates in exercise patients compared with control patients; these were men, younger than 51 years of age, who began exercise rehabilitation at least 5 months after myocardial infarction.252 Thirteen observational studies reported information regarding morbidity.71,83,183,184,190,204,205,229,253-257 None of these studies had a comparison or control group, and therefore, no meaningful conclusions could be drawn regarding the impact of exercise rehabilitation on rates of morbidity. Two meta-analyses of randomized controlled trials of cardiac rehabilitation also reported no significant difference in reinfarction rates in rehabilitation patients compared with control patients.53,54 No study documented an increased risk of reinfarction or other adverse cardiovascular outcomes for rehabilitation patients compared with control patients in a sizable database of coronary patients. Specifically, the randomized controlled trials included 3,640 patients, and the nonrandomized controlled trials included 938 patients. Followup as long as 10 years was reported.49 Two major surveys reported rates of cardiovascular events based on questionnaire responses by rehabilitation programs completing the surveys for two separate time periods. The initial survey involved 30 rehabilitation programs in the United States and Canada during 1960-77; a nonfatal cardiac arrest rate of 1/32,593 patient-hours of exercise and a nonfatal myocardial infarction rate of 1/34,600 patient-hours were reported.59 A larger survey of 142 U.S. cardiac rehabilitation programs (1980–84) reported a nonfatal myocardial infarction rate of 1/294,000 patient-hours.65 The results of these surveys establish that a low rate of serious cardiovascular events occurs in exercise-based cardiac rehabilitation. Caution regarding these rates of cardiovascular events is warranted because the data represent an aggregate analysis of information received from cardiac rehabilitation programs that were sent survey questionnaires and that provided data in a retrospective manner. Furthermore, the survey represents data from the 1980s and may not reflect contemporary management of coronary patients. |