Summary
Background
Few studies have analyzed the cost of treatment of chronic angina pectoris, especially in European countries.
Aim
To determine, using a modeling approach, the cost of care in 2012 for 1 year of treatment of patients with stable angina, according to four therapeutic options: optimal medical therapy (OMT); percutaneous coronary intervention with bare-metal stent (PCI-BMS); PCI with drug-eluting stent (PCI-DES); and coronary artery bypass graft (CABG).
Methods
Six different clinical scenarios that could occur over 1 year were defined: clinical success; recurrence of symptoms without hospitalization; myocardial infarction (MI); subsequent revascularization; death from non-cardiac cause; and cardiac death. The probability of a patient being in one of the six clinical scenarios, according to the therapeutic options used, was determined from a literature search. A direct medical cost for each of the therapeutic options was calculated from the perspective of French statutory health insurance.
Results
The annual costs per patient for each strategy, according to their efficacy results, were, in our models, € 1567 with OMT, € 5908 with PCI-BMS, € 6623 with PCI-DES and € 16,612 with CABG. These costs were significantly different ( P < 0.05). A part of these costs was related to management of complications (recurrence of symptoms, MI and death) during the year (between 3% and 38% depending on the therapeutic options studied); this part of the expenditure was lowest with the CABG therapeutic option.
Conclusion
OMT appears to be the least costly option, and, if reasonable from a clinical point of view, might achieve appreciable savings in health expenditure.
Résumé
Contexte
Les données économiques concernant la prise en charge des patients insuffisants coronariens en France sont parcellaires.
Objectif
Déterminer le coût annuel de prise en charge pour l’Assurance maladie en 2012, des 4 traitements utilisés pour prendre en charge l’angor stable : médicaments seuls, angioplastie avec stent nu, angioplastie avec stent actif et pontage aorto-coronaire.
Méthodes
Nous avons défini 6 situations cliniques correspondant aux différents états dans lequel peut se retrouver un patient un an après qu’il ait bénéficié d’un des 4 traitements. Pour chaque situation clinique, des soins étaient consommés et nous avons calculé le coût annuel de chaque situation. Nous avons défini, ensuite, pour chaque traitement, grâce à une recherche bibliographique, la probabilité à un an d’être dans l’une des 6 situations cliniques. Ceci nous a permis de calculer le coût moyen annuel de chaque traitement en tenant compte de son efficacité.
Résultats
Le coût moyen annuel était de € 1567 avec le traitement par médicaments, € 5908 avec l’angioplastie stent nu, € 6623 avec l’angioplastie stent actif et € 16 612 avec le traitement chirurgical. Ces coûts étaient significativement différents ( p < 0,05). Une partie des coûts était liée à la prise en charge des complications (hospitalisations pour infarctus, revascularisation et décès) : ceci représentait de 3 % à 38 % du coût annuel de chaque traitement.
Conclusions
Le traitement médicamenteux était la stratégie la plus économique après un an de suivi. Ceci laisse penser que le traitement conservateur peut être une source potentielle d’économie.
Background
In France in 2009, the direct cost, in terms of statutory health insurance, of the long-term disease named “coronary artery disease” (CAD) (affection de longue durée n o 13 « maladie coronarienne ») was € 4183 million, 50% of which was spent on inpatient care . Two main reasons explain this considerable cost. Firstly, there has been a huge increase in the number of revascularization procedures (percutaneous coronary intervention [PCI] and coronary artery bypass graft [CABG]). The use of angioplasty has increased rapidly since 1990 in most European countries, becoming the preferred method of revascularization around the mid-1990s. Secondly, the unit cost of PCI has increased with the widespread use of drug-eluting stents (DES). Indeed, DES have been the most important change in the management of CAD, as they reduce repeat revascularizations caused by restenosis, compared with bare-metal stents (BMS). In France in 2013, the unit cost of one DES was approximately twice that of a BMS. In real-life situations, however, the generalized use of DES has not led to the expected reduction in the total number of procedures performed .
Clinical data have failed to demonstrate clear superiority of any of the treatment modalities available (medical therapy alone, PCI or CABG) for stable CAD in terms of hard clinical events for non-specific populations (i.e. patients with diabetes, peripheral artery disease, etc.) . Numerous studies have assessed the cost-effectiveness of the different pairwise therapeutic options. There was no difference in the cost-effectiveness ratio after 4 years of follow-up between DES versus BMS in the ENDEAVOR II trial and between PCI versus contemporary medical therapy in the COURAGE trial . According to the results of the SYNTAX trial, there was a significant difference in the cost-effectiveness ratio in favor of DES after 1 year and CABG after 5 years of follow-up . Several variables explain the disparity in results of cost-effectiveness studies: the number and complexity of stenoses; the duration of patient follow-up; the changes in treatments over time; and the lack of studies comparing all four treatments simultaneously . In this context, the goal of our study was to determine the costs of the four conventional treatment modalities (drugs alone, PCI with BMS [PCI-BMS], PCI with DES [PCI-DES] and CABG), including ambulatory and hospital costs, to French statutory health insurance. We determined, first, the annual cost of different “clinical scenarios” (therapeutic successes or failures) for each of the four usual treatments for patients with stable CAD: optimal medical therapy (OMT), PCI-BMS, PCI-DES and CABG. The second aim of our study was to determine the average annual cost of each of these four usual treatments, taking into account the probability of occurrence of the different clinical scenarios. These costs were determined using a modeling approach, from the perspective of the French national payer.
Methods
Methodology overview
We first determined the possible clinical course over 1 year of any stable coronary patient, defining different clinical scenarios after one of the four usual CAD treatments: OMT, PCI-BMS, PCI-DES and CABG. We then determined the quantities of care consumed during 1 year for each of these clinical scenarios after each of the four treatments. Using the unit price of health care consumed, we calculated the cost of each clinical scenario. In a second step, we determined the probability of each clinical scenario depending on the treatment performed. Using the probability of each scenario and its cost, the total 1-year cost incurred by statutory health insurance for each treatment strategy was determined.
Study population
The study population comprised male and female patients, aged between 50 and 70 years, with stable CAD, defined as non-acute heart disease (i.e. no acute coronary syndrome or myocardial infarction [MI] in the last 24 hours).
Determination of clinical scenarios
We defined six different clinical scenarios that could occur over 1 year in any patient with stable CAD: clinical success, recurrence of symptoms without hospitalization or revascularization, MI, subsequent revascularization without MI, death from non-cardiac cause, and cardiac death. Clinical success was defined as the absence of the five other situations ( Fig. 1 ). A total of 24 possibilities thus existed (six clinical scenarios for each of the four initial treatment options).
The probability of a patient being in one of the six clinical scenarios after 1 year of follow-up, according to the initial treatment used, was determined from a literature search. The probabilities derived from published data were then validated by an expert committee (three cardiologists highly experienced in angina management and working in three different hospitals [Y.J., O.D. and N.D.]). Probabilities of a given clinical scenario that could not be determined from the literature were agreed upon by consensus of the three experts.
The literature search was performed on PubMed for publication dates ranging from 1990 to 01 June 2012. The keyword “stable angina” was combined with one of the three following keywords “stents [MeSH]”, “coronary artery bypass [MeSH]” or “drug therapy [MeSH]”. The following inclusion criteria were applied: randomized or observational studies; at least one of the four treatments investigated; clinical data available at 1 year follow-up (rate of recurrence of symptoms and/or MI and/or revascularization and/or cardiac death and/or non-cardiac death); and studies with at least 50% of patients with multivessel disease, to make comparison of all therapeutic methods appropriate. We excluded studies conducted exclusively on patients with diabetes mellitus.
We read the titles and abstracts of 2443 electronic references. Among them, the full text of 21 were read and 12 were selected: ARTS (Arterial Revascularization Therapy Study) ; CABRI (Coronary Angioplasty versus Bypass Revascularisation Investigation) ; COURAGE (Optimal Medical Therapy with or without PCI for Stable Coronary Disease) ; ERACI (Argentine Randomized Trial of Percutaneous Transluminal Coronary Angioplasty versus Coronary Artery Bypass Surgery in Multivessel Disease) ; e-SELECT registry (Sirolimus-eluting Coronary Stents in an Unselected Worldwide Population) ; Euro Heart Survey ; GABI (the German Angioplasty Bypass Surgery Investigation) ; MASS II (The Medicine, Angioplasty, or Surgery Study II) ; SoS (the Stent or Surgery trial) ; SPIRIT III (Comparison of an Everolimus-Eluting Stent and a Paclitaxel-Eluting Stent in Patients With Coronary Artery Disease) ; SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) ; and the SYNTAX PCI and CABG registries .
Costing method
Direct medical costs were estimated for 1 year and calculated from the resources used from the perspective of French statutory health insurance. Only costs related to treatment and complications were studied. Costs were expressed in 2012 euros (€). Because all the costs calculated were based upon reimbursements paid by statutory health insurance, these costs actually represent tariffs. We worked exclusively on reimbursement tariffs granted to public hospitals.
Health care consumption
Quantities of care consumed were determined from guidelines, assuming those guidelines were actually followed, and from clinical studies. If no information was available in the guidelines or in clinical studies, consensus was reached by the three expert cardiologists. The recommendations used were: “diagnosis and management of patients with stable ischemic heart disease” (American Heart Association, 2012); “coronary heart disease procedures and services” (Haute Autorité de Santé, 2012); and “guidelines on the management of stable angina pectoris” (European Society of Cardiology, 2006) .
Resources used were related to the treatment studied (OMT, PCI-BMS, PCI-DES or CABG) and subsequent care over 1 year of follow-up to manage therapeutic success or occurrence of complications.
Treatment studied
For the four treatments studied, drugs in the following therapeutic classes were used: aspirin, statins, angiotensin-converting enzyme inhibitors, beta-blockers, calcium channel blockers, nitrates and clopidogrel. The proportions of patients treated with each medication class came from the COURAGE and SYNTAX studies , and are presented in Table 1 . Drugs were assumed to be consumed for 1 year for the four treatments studied, except for clopidogrel, which was assumed to be taken for 1 month in case of treatment with PCI-BMS. For each drug, we assumed that the quantity consumed corresponded to the World Health Organization “defined daily dose” (DDD). In case of revascularization with PCI, we set the number of stents per procedure at 1.5 ± 0.8, in line with the average figure recorded in the national observational study of diagnostic and interventional cardiac catheterization (ONACI) .
| OMT | PCI-BMS | PCI-DES | CABG | |
|---|---|---|---|---|
| COURAGE | COURAGE | SYNTAX | SYNTAX | |
| Aspirin (12 months) | 95% | 95% | 91% | 84% |
| Statin (12 months) | 95% | 93% | 87% | 75% |
| ACE inhibitor (12 months) | 62% | 64% | 55% | 45% |
| Beta-blocker (12 months) | 89% | 85% | 81% | 79% |
| Calcium channel blocker (12 months) | 49% | 40% | 26% | 18% |
| Nitrates (12 months) | 67% | 53% | NA | NA |
| Clopidogrel (1 month) | – | 95% a | – | – |
| Clopidogrel (12 months) | – | – | 71% | 15% |
Subsequent care over 1 year
Resources consumed belonged to three categories: ambulatory care; hospitalization for complications; and medical transport. Resources used in the six clinical scenarios varied and are summarized in Table 2 .
| Clinical success | Recurrent symptoms | MI | Revascularization | Non-cardiac death | Cardiac death | |
|---|---|---|---|---|---|---|
| Ambulatory care | ||||||
| Four GP visits and one cardiologist visit | 100% | 100% | 100% | 100% | 100% | 100% |
| One resting ECG and one exercise ECG | 100% | 100% | 100% | 100% | 100% | 100% |
| One laboratory test a | 100% | 100% | 100% | 100% | 100% | 100% |
| Second visit to cardiologist | 100% | |||||
| Echocardiography | 25% | |||||
| Myocardial perfusion imaging | 25% | |||||
| Echocardiography and coronary angiography | 25% | |||||
| Myocardial perfusion imaging and coronary angiography | 25% | |||||
| Hospitalization | ||||||
| MI | 100% | |||||
| CABG ± cardiac catheterization or coronary angiography | 100% | |||||
| Death during a non-cardiac hospitalization | 63% | |||||
| Death during a cardiac hospitalization | 48% | |||||
| Medical transport | ||||||
| Emergency medical services (SAMU) | 74% | 0% | 40% | 74% | ||
| Private ambulance | 14% | 21% | 10% | 14% | ||
| Fire brigade | 12% | 0% | 40% | 12% | ||
| Medical taxi | 0% | 7% | 10% | 0% | ||
a Lipid profile, plasma creatinine, haemogram and fasting glucose.
Regarding ambulatory care, for the four treatments, and for all clinical scenarios, average consumption over 1 year was set at: four consultations with a general practitioner; one consultation with a cardiologist with performance of a resting electrocardiogram and a stress electrocardiogram; and laboratory tests, including lipid profile, fasting blood glucose, plasma creatinine and a blood cell count. In addition, for the “recurrence of symptoms without revascularization or hospitalization” scenario, whatever the treatment modality, guidelines recommend that the patients consult their physicians, without defining the frequency of the visits; we hypothesized that patients in this clinical situation had two visits with their cardiologists during the year. As guidelines also recommend in this clinical scenario performance of non-invasive and/or invasive testing, we proposed the following: stress echocardiography in 25% of patients; radionuclide myocardial perfusion imaging in 25%; echocardiography and coronary angiography in 25%; and myocardial perfusion imaging and coronary angiography in 25%.
Regarding hospitalization for complications, for patients with the clinical scenario “MI”, according to the data of the French registry FAST-MI, we knew that 77% had been hospitalized with the French diagnosis-related group (DRG) entitled “stent with MI” . In addition, according to the ONACI data, we assumed that the number of stents implanted per patient was 1.5 ± 0.8 and that 55% of stents implanted were BMS . For the remaining 23% of patients in the clinical scenario “MI”, we considered that they had not been revascularized and that they were hospitalized with the DRG entitled “MI”. All patients with the clinical scenario “revascularization without MI” were hospitalized according to the DRG with one of these items: “CABG with cardiac catheterization or coronary angiography” or “stent without MI”. Moreover for the “stent without MI” DRG, we also added the number of implanted stents according to data from ONACI (i.e. 1.5 ± 0.8).
Because two French national databases used death certificates (Inserm-CépiDC, which studied medical cause of death in and out hospital , and the French Programme of Medicalization of Information Systems [programme médicalisé des systèmes d’informations; PMSI] ) we knew that among patients who died of a non-cardiac cause in 2012 (i.e. clinical scenario “non-cardiac death”), 63% died in hospital. Among patients who died from a cardiac cause (clinical scenario “cardiac death”), 48% died during inpatient stay. We assumed in our models that the dead patients died on the 365th day of follow-up. Therefore, dead patients were supposed to have consumed all planned care (inpatient and outpatient), as would patients who were alive at the end of the first year.
Regarding medical transport, reimbursed transport to the hospital could be used in all clinical scenarios requiring hospital admissions (i.e. “MI”, “revascularization without MI”, “non-cardiac death” and “cardiac death”). According to the personal data of the principal investigator of FAST-MI, patients with “MI” used emergency medical services in 74% of cases, private medical ambulances in 14% and the fire brigade in 12%. According to an unpublished study performed in our hospital, patients hospitalized for an elective “revascularization without MI” (PCI or CABG) used private medical ambulances in 21% of cases and a reimbursed taxi in 7%. Other patients used their own transport. Because there are no French data about medical transport used by patients in the clinical scenario “cardiac death”, we assumed these patients used the same transport as the “MI” patients. Finally, for “non-cardiac death”, which represents a large variety of serious diseases, we hypothesized that patients used emergency medical services or the fire brigade overwhelmingly, which is why we fixed the following proportions for medical transport in this clinical situation: emergency medical services in 40% of cases, the fire brigade in 40%, private ambulances in 10% and reimbursed taxis in 10%.
Cost of health care resources
The unit costs of outpatient medical products and services and of hospitalization were based on the costs to French statutory health insurance . All costs were calculated for 2012 from the perspective of the French national payer.
To calculate the cost related to the use of drugs, we first calculated the daily unit cost of each drug that is potentially useful in the treatment of CAD (i.e. atorvastatin, diltiazem, clopidogrel, etc.); for each drug we multiplied the DDD by its unit price, weighted by the available proportions of brand name and generic versions (available from the French database MEDIC’AM ) ( Table 3 ). Then, we calculated the unit cost of each therapeutic class (e.g. the daily unit cost of statins). To do this we multiplied the daily unit cost of each drug belonging to the same therapeutic class by the proportion of each drug in this therapeutic class (data from the MEDIC’AM database) ( Table 4 ).
