Epidemiology and economic burden of chronic heart failure

Abstract

Chronic heart failure is a major cause of morbidity and mortality in the general population. Both, the increasing age of the population and success in the treatment of patients with acute myocardial infarction rise the prevalence and thus the economic expenditures of chronic heart failure. This holds true despite recent improvement in survival of patients with congestive heart failure due to treatment with ACE inhibitors, β-adrenoceptor blockers and aldosterone antagonists. Chronic heart failure consumes 1–2% of the total healthcare resources in the industrialised countries with increasing tendency in future. The most effective approach for preventing heart failure is an improvement in diagnosis and consequent treatment of arterial hypertension. Evidence based treatment of congestive heart failure is both effective in lowering morbidity and mortality as well as cost-effective from an economic point of view.

Trends in the epidemic of chronic heart failure

The aging population results in a dramatical rise in the prevalence of heart failure

National population projections report that approximately 12.7% of the US-population was 65 or older in 2000. Twenty years later, 16.5% are estimated to be in this age group.¹ Since it is well established that the incidence and prevalence of chronic heart failure is highest in the older population,² we face a dramatical increase in the prevalence of heart failure. Furthermore, the success in the treatment of acute myocardial infarction also leads to an increase in the prevalence of heart failure. Thus, an approximate three-fold increase in the annual prevalence of chronic heart failure has been observed over the past decade.³ The actual prevalence of heart failure in the developed countries is 1–2% of the general population.⁴

Despite new data from the Framingham Heart Study-population, indicating that the incidence of heart failure has declined significantly over the last 50 years in this community,⁵ the incidence of heart failure is rising in most countries over the last years. No difference in the sex- and age-adjusted incidence of heart failure was observed using data from over 5 million persons including approximately 30,000 persons suffering from heart failure in the US between 1989 and 1999.³ An improvement in blood pressure control or preventive strategies for coronary artery disease (such as lipid lowering drugs) may help to reduce the incidence of chronic heart failure, see Fig. 1.

Survival after the onset of heart failure is improving only slowly

Once left ventricular dysfunction is present, it usually progresses, albeit not predictably. Survival is usually good in patients with asymptomatic and mild signs of left ventricular dysfunction or clinical signs of heart failure. However, annual mortality rates are extremely high in patients once decompensating or in patients functionally classified NYHA IV peaking up to 80% per year.⁶ Deaths are mainly attributed to sudden cardiac death and worsening heart failure (both approximately 40% of cases).

Fortunately, it is also reported from the Framingham Heart Study, that there is a substantial improvement in the survival rate after the onset of heart failure of approximately 12% per decade.⁵ This improvement may be due to an increasing use of pharmacological interventions that prolong survival.^7–13 These data are supported by a recent analysis of 23,505 patients hospitalised with heart failure in Northeast Ohio. From 1991 to 1997, the 1-year mortality declined by −5.3%, a relative decrease of 14.6%.¹⁴

Despite this favorable trend, mortality of patients suffering from heart failure remains high: more than 50% of patients died within 5 years once diagnosed for heart failure in 1990⁵ indicating the need for a better strategy for prevention and treatment of heart failure patients. In addition, epidemiologic data and prospective studies on the incidence and outcome of patients with diastolic heart failure are still lacking.

The economic impact of chronic heart failure

Heart failure is diagnosed in 1–2% of the general population in developed countries.⁴ Direct costs due to heart failure were (in one million € per one million population) 26 in the UK, 37 in Germany, 39 in France and 70 in the US, respectively. In the US $ 38 billion have been spent for patients with chronic heart failure in 1991 and the expenditures for heart failure were higher than that for the treatment of cancer and myocardial infarction.¹⁵ Overall, chronic heart failure consumes 1–2% of the total healthcare resources in the developed countries. The economic burden of heart failure may become unmanageable in the setting of an ageing population indicating the need for cost-effective treatment options and preventive strategies.

Repeated hospitalisations are not only a powerful marker of poor prognosis and of poor life quality but also for increased costs for the health care system

The direct costs are mainly attributed to hospitalisations (approximately 75%), with an average cost of approximately € 10,000 per patient per hospitalisation.¹⁵ In the EuroHeart Failure survey programme 24% of patients had been readmitted to hospital within 12 weeks of discharge.¹⁶ The three main causes of hospitalisations due to chronic heart failure are sodium retention (55% of cases), angina or myocardial infarction (25%) and arrhythmia (15%).¹⁷ In this context, outpatient management programs may be a suitable strategy for managing the burden of heart failure.¹⁸ Adequate fluid control is an increasing need not only for a better quality of life but also to improve prognosis of patients with symptomatic heart failure.

Pharmaco-economics of chronic heart failure

The EuroHeart survey demonstrates that only 17.2% of heart failure patient were under the combination of a diuretic, ACE inhibitor and β-adrenoceptor blocker,¹⁹ indicating the underuse of a life prolonging and a potentially cost-effective medication. The question of great concern still remains unanswered which pharmacological strategy can potentially reduce the burgeoning costs of heart failure patients without compromising the quality of life.

Diuretics

Diuretics play a significant role in the treatment of edema and fluid retention associated with chronic heart failure and thus for the need for hospitalisation. Since in 55% of cases sodium retention and edema are the leading cause for admission to the hospital¹⁷ and given the low drug costs, treatment with a diuretic is most likely cost-effective. In a few trials, it has been demonstrated that the choice of diuretic influences cost-effectiveness. It is well established that the more expensive torasemide is more cost-effective that furosemide (approximately four times less expensive than torasemide).^20–21 The cost-effectiveness will increase further when torasemide will be offered in a generic formulation in near future. Thus, besides a favourable clinical benefit, torasemide may be advantageous from a pharmaco-economic point of view as well.

Aldosterone receptor antagonists

Spironolactone treatment prolongs survival in patients suffering from severe heart failure when added to standard therapy.¹³ A recent Irish trial found that the incremental cost-effectiveness ratio for spironolactone therapy was € 466 per year of life gained and thus was highly cost-effective in the Irish healthcare setting.²²

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-Adrenoceptor blockers

The treatment of chronic heart failure with β-adrenoceptor blockers without intrinsic sympathomimetic activity has reduced mortality and morbidity considerably.^7–10 The incremental expected cost per year of life saved is $ 3300 for bisoprolol, $ 2500 for metoprolol and $ 6700 for carvedilol.²³ These costs for 1 year of life saved are well below accepted standards for cost-effectiveness (CABG in three vessel disease costs € 51,000 per year of life saved compared to medical treatment). In the respective clinical β-adrenoceptor blocker trials, the withdrawal rates were in favour of carvedilol^7–10 and it may be considered that drugs not taken by the patients are the most expensive ones.

ACE inhibitors

ACE inhibitors are well established in the treatment of chronic heart failure and the first class of drugs that has shown to reduce mortality and morbidity.^11,12

In the SOLVD study extensive analyses have been done in terms of cost-effectiveness.²⁴ The economic analysis indicated that therapy with enalapril resulted in estimated net savings per patient of $ 3198 and $ 744 during the Treatment and Prevention Trials, respectively (average follow-up of 2.8 years). In the Treatment Trial (patients with left ventricular dysfunction and overt heart failure) the probability that enalapril improved survival and decreased costs was 0.94. In the Prevention Trial (patients with left ventricular dysfunction without overt heart failure) the cost per life year saved was estimated to be $ 1820. This data indicate that ACE inhibitors are highly cost-effective and provide benefits in heart failure patients also from an economic viewpoint.

The ATLAS study has given evidence, that higher doses of ACE inhibitors are more cost-effective than low doses.²⁵ Expected monthly expenditures from the third party payer perspective were € 347 per patient in the low dosage group (2.5 or 5.0 mg lisinopril per day) and € 319 per patient in the high dosage group (32.5–35 mg lisinopril per day), indicating that high doses of ACE inhibitors should be used from a pharmaco-economic viewpoint.

Thus, agents should be used in doses shown to be effective in reducing symptoms and shown to prolong life. This holds true for ACE inhibitors as well as for β-adrenoceptor blockers. The recent published COMET trial adds substantial evidence for the use of high dose β-adrenoceptor blockers (either metoprolol or carvedilol) when treating patients with heart failure.²⁶

Non-pharmacological treatment options in chronic heart failure

Implantable Cardioverter Defibrillators

Implantable Cardioverter Defibrillators are indicated in patients with chronic heart failure at risk for sudden cardiac death due to ventricular tachycardia or ventricular fibrillation. In the MADIT-II study it is shown that the mortality risk of patients with previous myocardial infarction and low left ventricular ejection fraction (30% or lower) may be reduced by 31% in the following 2 years after implantation of a cardioverter defibrillator without expensive preoperative screening (i.e. electrophysiological study).²⁷ However, the high cost of treatment raises questions regarding its cost-effectiveness. A recent meta-analysis reports a cost per life-year gained between $ 30,181 and $ 185,000 based on three large clinical trials.²⁸ However, stratified analyses showed that Implantable Cardioverter Defibrillators may be a cost-effective option in patients at high risk for ventricular tachycardia or ventricular fibrillation. However, further research on patient selection criteria is needed to define a subgroup of heart failure patients in which Implantable Cardioverter Defibrillators are a well-accepted cost-effective treatment option.

Cardiac resynchronisation therapy

Cardiac resynchronisation therapy (CRT) is now established in the treatment of patients with heart failure and intraventricular conduction delay. Given the complex technology and the complex implantation procedure, health care costs may rise by the use of CRT. However, it has been convincingly demonstrated that a reduction of hospital days can be achieved by this treatment option.^29,30 Since hospital treatment constitutes 75% of health care costs for heart failure, this therapy may prove to be a cost-effective option in the long run. However, results of prospective clinical trials are needed before its use in the standard clinical setting may be considered.

Conclusions

The prevalence of heart failure is high and is expected to further increase due to the aging of the population. It is unclear whether the socio-economic burden of heart failure will be manageable.

Besides the common underuse of effective heart failure medications, these drugs (diuretics, ACE inhibitors, β-adrenoceptor blockers, spironolactone) have given evidence to be cost-effective. Thus, optimal pharmacological treatment should be aspired to decrease the burden of heart failure also from the socio-economic point of view.

Whether or not non-pharmacological treatment options, as implantable cardioverter defibrillators or biventricular pacemakers may decrease costs on the long run has to be addressed in further studies.

References