Contemporary guidelines

 A number of international guidelines provide recommendations for diagnosis and management of patients with PAD.3-5 IC patients are at risk for cardiovascular events and thus require intensive risk factor modification. Levels of blood pressure, glucose and cholesterol should be optimized. Attention should be paid to smoking cessation as nicotine use is the most important modifiable vascular risk factor. Antiplatelet therapy and statins are indicated for all IC patients as a means to reduce the risk of cardiovascular events.6

 To relieve PAD related symptoms, a supervised exercise therapy regimen (SET) is advised as an initial treatment modality in these international guidelines.3-5 Several studies have demonstrated that some level of supervision is necessary to optimize results. Conversely, general and unstructured exercise recommendations that are haphazardly provided by a physician do not result in any clinical benefit.7-10

An update

 SET is effective as a treatment for IC.7-10 In chapter 2 a systematic meta-analysis was performed confirming that SET improves maximum treadmill walking distance compared to non-supervised exercise therapy regimens. Compared to the 2006 edition,7 which revealed a significant overall effect size of 0.58, an increase to 0.69 was found, corresponding with an approximately 180 meters increase in walking distance favoring the supervised group. SET

179
was also beneficial when maximum and pain-free walking distances at 12 months were
considered. However, a significant effect on quality of life parameters as evaluated using a
SF-36 questionnaire was not found.

A stepped care approach

 Supported by this body of evidence, by international guidelines and by the

Hippocratic oath adagium 'primum non nocere', SET should be offered to all IC patients as a
first-choice treatment option.3-5 Invasive means of limb revascularization, either minimally
invasive (percutaneous transluminal angioplasty, PTA) or by means of conventional 'open'
vascular surgery, should only be considered if a patient fails to respond to this conservative
approach. This so-called stepped care model (SCM) is illustrated in figure 1.

 

 In chapter 3 it is reported that in 2009 only 14% of the patients were treated with a

SCM, while 28% of the patients primarily received a revascularization, of which 51%
concerned aortoiliac lesions. More than half (58%) were assumed to have received a proven
inferior non-supervised walking advice (chapter 2). Ambiguities in the TASC II guideline may
be responsible for a too liberal use of invasive procedures in patients with IC due to
aortoiliac lesions.3 The role of invasive interventions as primary treatment for this type of
lesion is unfortunately still subject of debate in current daily practice. The CLEVER trial
demonstrated that SET resulted in a superior treadmill walking distance after 6 months
compared to PTA with stent revascularization in aortoiliac disease, but a non-significant
greater improvement of disease-specific quality of life in favor of PTA.11 The question that
Figure 1. Schematic overview of the Stepped Care Model
may be asked is: Why do most patients do not receive SET at all? Causes are multifactorial and depend on the physician who should prescribe SET as a first line treatment, on the patient who should be willing to comply with SET as a first line treatment, and on the health insurer who should reimburse SET.

Reimbursement issues versus costs

 Unfortunately , there is no adequate reimbursement policy for IC worldwide.12,13 Nationwide implementation of SET programs was thought to require a substantial investment in most countries.14 Although several cost-effectiveness analyses were performed supporting a SET first treatment strategy14-19, no study investigated the overall economic consequences of a nationwide SCM implementation.

 

 In chapter 3 a cost-analysis is performed 'as if a SCM (figure 1) was implemented' in the Dutch healthcare system. Costs of IC treatment were calculated and compared to estimated costs associated with a theoretical increase of nationwide SCM implementation. Invoice data of all patients with IC in 2009 were obtained from a Dutch health insurance company (3.4 million members). Patients were divided into three groups based on initial treatment as followed after diagnosis (t0). The (first) SET group received SET initiated at any time between 12 months before and up to 3 months after t0, which was considered as Stepped Care. The (second) intervention group (INT) underwent endovascular or open revascularization between t0 and t+3months. The third group (REST) received neither SET nor an intervention. All peripheral arterial disease related invoices were recorded during 2 years, and average costs per patient were calculated. Savings following use of a SCM were calculated for 3 scenarios. These scenarios were based on two critical success factors (the surgeons' compliance (willingness) to refer each IC patient to SET and the patient's motivation to participate in a SET program).

 Despite the fact that, according to contemporary international guidelines, all patients with IC initially should be referred for SET3-5, this ratio was hypothetically set to 80% (best), 50% (moderate) and 30% (worst) based on reimbursement issues, appreciation of SET by vascular surgeons and preference (although evidence to do so is lacking) for a revascularization in certain cases. The patient's motivation to participate in a SET program, which largely depends on level of reimbursement as well as a thorough understanding of the benefits of a SET program in comparison to an invasive intervention, was set to 80% or 25%. In total, three potential scenarios were considered: best (80%-80%), moderate (50%-80%) and worst case (30%-25%).

 

 The percentage of patients who received a SCM in 2009 was 14.1%, while 27.5% and 58.3% were treated with invasive revascularization, or neither of both, respectively. Within two years from t0, invasive revascularization in the SET group was performed in 45 patients (6.4%). Additional interventions (primary at other location and/or re-interventions) were performed in 480 INT patients (35.2%). Some 431 REST patients received additional SET (n=299, 10.3%) or an intervention (n=132, 4.5%). Mean total IC related costs per patient were €2191, €9851 and €824 for SET, INT and REST, respectively. Based on a hypothetical

worst, moderate, and best case scenario, some 3.8, 20.6 or 33.0 million euros would have been saved per year if SCM was implemented in the Dutch health care system.

A worldwide extrapolation: Savings up to 1 billion €'s?

 Despite limitations inherent to its retrospective character, this cost-analysis study added an important finding to the already existing body of solid evidence supporting SET as first line treatment for patients with IC. Extrapolation of these results (based on reported costs for SET and invasive interventions in the rest of Europe and the USA, having a low penetration of (community-based) supervised exercise programs and thus a low threshold for invasive vascular interventions) suggests that savings of around 1 billion euro's may be achieved.

Are costs really the problem?

 Despite the finding that implementation of a SCM is beneficial concerning costs for healthcare insurers (a potential increase of quality of care at lower costs), it may seem that patients as well as their physicians are reluctant to embrace a SCM strategy. A significant number of claudicants is after a 'quick fix' of their problem. Therefore, they are not willing to adhere to a lengthy exercise program. They rather prefer a 'magic polypill' or a swift intervention. By doing so, the burden that is placed on their personal life is minimal. With a SCM, patients are obliged to make a concerted lifetime effort, to change their life-style and to increase their ambulatory activities.20 This is generally not what they expected when consulting their physician. Moreover, it's hard to comply with, as they were typically sedentary for much or all of their lives.21

 

 Another possible explanation of the unpopularity of SET is put forward by the hypothesis that some physicians do not prefer SET.22,23 Vascular surgeons and interventional radiologists are remunerated for the execution of interventions. They opt for these invasive treatments because they are convinced that they optimally serve their patients, they like to perform these interventions whereas their skills have to be trained or improved.22 The more complex and 'avant garde' an intervention is, the better the clinician's kudos within the hospital and at conferences.22 These sentiments are obviously augmented by the medical industry exerting aggressive promotion of new invasive techniques. In contrast, SET lacks promotion16,22.

Beneficial side effects of a mandatory three-month trial period of SET

 Above-mentioned statements possibly contributed to our low 14% SCM implementation ratio (chapter 3). However, apart from decreasing costs, the SET component of a SCM may reduce cardiovascular mortality and morbidity as collateral beneficial side effects.24 Moreover, starting with SET may provide awareness of important functional restrictions in daily life other than caused by IC (e.g. COPD, congestive heart failure, osteoarthritis, spinal stenosis, equilibrium disorders). As a benefit, SET as a systemic treatment modality treats both legs. So by following a SCM strategy, potentially futile

vascular interventions in polymorbid patients who are limited by more than IC alone may be prevented. Implementing a SCM approach, more or less stimulating patients and physicians to try 'SET first', preserving 'invasive treatment next' for those not responding to SET, suits well in a world with rapidly rising health care system costs25.

Is SET safe?

 A frequently used argument not to refer patients for SET is the matter of safety.23 Some fear the onset of cardiovascular events that may possibly occur during exercise in a population with known cerebral and coronary artery disease.26,27 In a nationwide survey among Dutch vascular surgeons, approximately 70% were convinced that coexisting cardiopulmonary comorbidity and/or aorta–iliac stenosis or occlusion were relative contra-indications for SET participation.23 In chapter 4, SET related complications in patients with IC were systematically studied in a meta-analysis. A total of 74 articles representing 82,725 hours of training in 2,876 IC patients met inclusion criteria. Eight adverse events were reported, six of cardiac and two of non-cardiac origin, resulting in an all-cause complication rate of 1 per 10,340 patient-hours. It was concluded that SET could safely be prescribed to all patients with IC as an exceedingly low all-cause complication rate is found during SET. Furthermore, routine cardiac screening prior to commencing SET is not advised.

How to increase a Stepped Care approach nationwide?

 It may seem that physicians, healthcare insurers as well as patients do not like SET22. As a consequence, SET is seriously underused as a therapeutic tool for IC in current clinical practice.12,13 Some also hypothesized a supposed shortage of supervised settings to which patients can be referred to, or the necessity for patients to travel to a SET facility as potential causes for this underutilization.12,13 To overcome these potential blockades, a community-based SET program was instigated28 that appeared effective after 3 and 6 months.29 Based on these results, a nationwide community based SET network was initiated providing a 100% SET availability in the Netherlands.12,30 In chapter 5, this network, based on the World Health Organization chronic care framework, is presented in combination with the introduction of innovative technologies to simulate SCM implementation. This concept termed ClaudicatioNet was launched in 2011 in the Netherlands as a means to tackle some of earlier described shortcomings in IC treatment and to stimulate cohesion and collaboration between stakeholders.30 The overall goal of ClaudicatioNet is to stimulate quality and transparency of IC treatment by optimizing multidisciplinary healthcare chains on a national level. In this model, all patients suffering from IC are initially subjected to an extensive community-based SET program performed by a qualified and trained physiotherapist for at least 2-3 months before an invasive procedure is proposed (SCM)30. SET is improved by stimulating both a theoretical and practical knowledge base. eHealth and mHealth technologies are used to create insights of provided care, to enhance quality control management, to facilitate patient empowerment and to stimulate life-style change.

It is likely and subject of continuous research that the ClaudicatioNet concept will create a more efficient and cost effective management of IC.

Conclusions

 The incidence of intermittent claudication (IC) is increasing worldwide whereas health care costs are progressively unaffordable (from 13% of national income in 2012 to a calculated 31% in 2040 in The Netherlands)25. Therefore, potential novel strategies for IC prevention and optimum treatment are required.

Current guidelines advocate the use of SET for IC3-5, as this tool is superior compared to a non-supervised exercise regimen (chapter 2). Moreover, SET is safe (chapter 4), possibly even more effective, durable and less harmful than a revascularization 11,17,31-38, and certainly less expensive (chapter 3). At present, there is a nationwide availability in the Netherlands (chapter 5). However, a contradictory situation concerning the initial treatment of IC patients in the Netherlands is at hand. Despite the high availability of SET programs, a low referral rate of 14% was found (chapter 3). Although further research would be helpful (and is certainly required), the main blockage of adopting SET is apparently not a lack of evidence (other areas of vascular surgery practice have enthusiastically embraced other treatment modalities despite a much lower level of scientific justification).22 The patient's and doctor's unwillingness and misconceptions to participate in combination with the anxiety among healthcare insurers all seem to contribute SET underutilization and unnecessary health expenditure. The introduction of a Stepped Care Model with a mandatory three-months trial period of SET according to the ClaudicatioNet quality standards might reduce this mismatch and could be beneficial for all stakeholders. It must be appreciated that politicians, health care insurers, physicians as well as patients should all head in the same direction in order to optimize the implementation of this approach. Quality of care is thus increased whereas financial profit is gained. The overall consequence of this approach on the Dutch as well as European and USA society should be subject of future research.