Background
Cardiovascular diseases are a major cause of mortality and morbidity, contributing to about 30% of all-cause mortality and 10% of the total disability-adjusted life-years globally [
1]. Although advances in medical therapy and revascularization surgery have improved outcome, reducing risk factors associated with cardiovascular diseases remains an important strategy in lowering the global burden of disease [
2]. Risk factor management is a core component of cardiac rehabilitation, which in turn forms part of the overall management of patients with cardiovascular diseases such as coronary artery disease or chronic heart failure [
3,
4].
Besides risk factor management (specifically control or reduction of lipids, blood pressure, body weight, diabetes mellitus and cigarette smoking), the other core components of cardiac rehabilitation include nutritional and physical activity counseling, psychosocial interventions and exercise training [
4]. In particular, exercise training is often the component being examined under the umbrella term ‘cardiac rehabilitation’, likely because of its duration and therefore the cost of the program [
5].
Several systematic reviews over the past three decades have consistently demonstrated cardio-protective effects of exercise-based cardiac rehabilitation programs [
6‐
9]. Exercise-based cardiac rehabilitation, compared to usual care, reduces all-cause mortality by 20% (95% confidence interval, CI: 7%, 32%) and cardiac mortality 26% (95% CI: 4%, 39%) [
8]. Risk factors such as total cholesterol, triglycerides, systolic blood pressure and self-reported smoking habits were also significantly reduced [
8]. The pooled sample size for the most recent systematic review was 8,940, most of whom had undergone at least two months of cardiac rehabilitation under supervision of professional exercise personnel [
8]. This implies great involvement of economic cost in the delivery of cardiac rehabilitation.
Economic evaluation of cardiac rehabilitation has been reported since the 1980s. A systematic review of economic evaluation studies on cardiac rehabilitation, which identified 15 studies, was reported in 2005. Based on studies published between 1985 to 2004, supervised cardiac rehabilitation, compared to usual care, resulted in USD2,193 to USD28,193 per life year gained, and USD668 to USD16,118 per quality-adjusted life years(monetary values were 2004 US dollars) [
10]. Most of the studies reviewed up to 2004 were based on prospective randomized controlled trials conducted much earlier than their published dates. Over the past five years, more economic evaluation studies emerged. These studies might involve patients who have undergone more recent medical therapies for coronary artery disease and chronic heart failure. Recent studies have also focused on comparisons among different modes of delivery of cardiac rehabilitation, such as programs that were outpatient-, inpatient- as well as home-based. Therefore it is timely to systematically review and summarize the evidence on cost-effectiveness of cardiac rehabilitation.
The overall objective of the current systematic review was to describe and summarize published economic evaluations of cardiac rehabilitation for comparing the cost-effectiveness of different modes of delivery of cardiac rehabilitation. The specific aims were to compare the following modes of delivery:
(a)
supervised cardiac rehabilitation versus no cardiac rehabilitation,
(b)
supervised versus home-based cardiac rehabilitation,
(c)
inpatient (not Phase I ward program, but residential Phase II program) versus outpatient cardiac rehabilitation, and
(d)
home-based cardiac rehabilitation versus no cardiac rehabilitation.
In this review, cardiac rehabilitation is considered as consisting of at least exercise training sessions, as this is usually the component studied as well as being the main cost driver of cardiac rehabilitation programs.
Discussion
This systematic review summarizes the cost-effectiveness of cardiac rehabilitation compared to no cardiac rehabilitation, for patients after myocardial infarction, revascularization surgery or percutaneous coronary interventions, as well as those with chronic heart failure. Pooling of results is not possible given the heterogeneity in perspectives, health systems, study designs, details of cardiac rehabilitation interventions and types of patients that exist among the studies included in this review. However, we contend that these studies provide sufficient evidence for policy development concerning cardiac rehabilitation.
Inclusion of a supervised outpatient cardiac rehabilitation program is clearly more cost-effective than not including cardiac rehabilitation program (“usual or standard care”) into the overall management of patients after myocardial infarction or those with chronic heart failure. The centre-based programs consisted of exercise-based sessions, three times a week, over a period of 8 to 12 weeks. In addition, risk factor management and other multidisciplinary input were included in half of these studies.
Four of the nine studies were economic evaluations alongside prospective randomized controlled trials [
14,
16‐
18]. Two of these studies examined cost-effectiveness from the societal perspective within differing health systems [
14,
16]. In the Canadian health system, cardiac rehabilitation compared to usual care had an incremental cost-effectiveness of USD9,200 per quality-adjusted life-year (QALY) gained as well as USD21,800 per life-year saved (1991 US dollars) at 12 months [
14]. In the United States’ private health care system, cardiac rehabilitation was the dominant strategy compared to no cardiac rehabilitation with $1,773 (2001 US dollars) per life-year saved at 14 months [
16]. Recent economic studies with non-randomized group allocation designs corroborated this observation, for example, an incremental cost-effectiveness ratio of $13,887 per life-year saved (1998 US dollars) was estimated based on Medicare expenditures for American patients undergoing cardiac rehabilitation; these patients had concomitant end-stage renal failure requiring haemodialysis and post-coronary artery bypass graft surgery [
19]. In Belgian patients following percutaneous coronary interventions, cardiac rehabilitation led to reduced hospitalization and revascularization surgery, and subsequently cost (published in 2008, in euros) [
20]. One economic modeling study suggested that cost savings could become less over the years as a result of rising health care costs [
15]. Much of the cost escalation could be attributed to the high costs of cardiac investigations and surgery, in addition to the personnel-intense multidisciplinary cardiac rehabilitation program [
26]. Therefore, home-based programs have been touted as a cost-effective alternative.
Comparisons between home-based and centre-based programs were predominantly cost-minimization studies [
17,
21,
23,
24,
28,
33]. In all these studies, the consequences of both alternatives were equivalent, so the authors sought to only compare their costs. Despite different settings, these studies consistently showed that home- and centre-based cardiac rehabilitation to be similar in cost.
Although all 13 studies (including cost-minimization analyses) on home-based cardiac rehabilitation, compared to either supervised centre-based programs or no cardiac rehabilitation, have demonstrated home-based model to be cost-effective or cost-saving, the contents of the home-based programs varied widely. The contents of home-based program ranged from actual exercise sessions at home [
21,
22,
33], frequent home visits by case managers and physicians [
24‐
26,
28], to reduced or more spaced-out attendances at the centre [
17,
23,
25,
27]. Exercise participation has to be regular to be effective. The option of reduced or spaced-out attendances at the centre is primarily to encourage the patients to continue with the exercises at home, whilst providing opportunity to return to the centre for reinforcement, monitoring and evaluation. One program was internet-based, requiring computer literacy, internet access at home and frequent log-ons to the web site to update on completion of exercises [
31].
Early studies (before 2005) tended to demonstrate that home-based programs were more cost-effective and cost-saving than centre-based ones [
17,
21‐
24,
33]. Sensitivity analyses in some of these studies have shown no change to the conclusion despite taking the worst-case scenario[
17] or varying variables such as costs [
24], readmission rates [
24], patients’ travelling time [
24], exercise adherence [
22] and discounting rates [
22,
24]. Home-based programs in these studies were varied, including program with reduced sessions at the centre to exercise program conducted entirely at home with or without frequent home visits by health care professionals (see Table
3). However, the recent studies have shown otherwise [
25‐
28]. Three recent studies demonstrated no significant difference in the cost-effectiveness of centre-
versus home-based programs [
25,
26,
28]. In one study, sensitivity analyses by taking the upper estimate of UK hospital rehabilitation costs did not alter the conclusion, because cardiac-related costs far exceeded rehabilitation costs [
26]. All three economic evaluations were conducted alongside randomized controlled trials, within a taxation-based health care system (Canada and UK) and involved multiple home visits by health care professionals (case managers, physicians and rehab nurses). One recent study demonstrated greater quality adjusted life-year gained among participants in centre-based program than those in home-based program [
27]. The “home-based” program in this study was 33 cardiac rehabilitation sessions spread across 12 months, whereas the centre-based program was the same 33 sessions conducted over 3 months. Interestingly, these authors found that the spread-out program was more cost-effective among women whilst the centre-based program was more cost-effective among men [
27]. Thus, the cost-effectiveness of the so-called home-based cardiac rehabilitation program depends heavily upon its contents as well as patient profiles. Policy decision makers, and payers or purchasers of cardiac rehabilitation services, should take into consideration of the model of home-based programs when considering resource allocation. The use of information and communication technology and internet-based programs should be explored, and therefore further studies could compare internet-
versus centre-based programs in terms of cost-effectiveness.
Limitations
None of the 16 articles met all of Drummond’s 10-item checklist (Table
2). Articles were dated as early as 1985 and as recently as 2009, with 13 of the articles published in the last 10 years. Majority of the studies collected and analyzed only direct medical costs. Few studies considered sensitivity analysis to account for uncertainty in costs and consequences. Although none of the foreign-language articles were included, none met the inclusion criteria for review. Publication bias cannot be excluded as almost all the economic evaluations demonstrated cost-effectiveness.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
WPW and JF performed article search and screened the abstracts. KHP resolved any disagreements arising from the primary reviewers’ interpretations of the articles and provided input to the manuscript. JL provided input to the interpretation of the review and discussion. All authors read and approved the final manuscript.