Our study showed that in Spain, during the 2015-2019 period HF associated costs were high (patient total cost of 15,373 Euros), being cardiovascular hospitalizations the most important determinant (75.8%), particularly HF hospitalizations (51.0%). Total medication cost accounted for 7% of the total HF cost. In addition, the annual cardiovascular hospitalization mean cost progressive decreased over time.
In our study, the prevalence of HF was about 1.8%. With regards to the HF population, mean age was 77 years, around half of patients had systolic HF, the majority of patients were on NYHA functional class II or III, one third had diabetes and comorbidities were common. In Spain, the studies performed in different clinical settings (hospital and outpatients) show a higher prevalence of HF [22]. However, the population-based studies report similar numbers to our study [23]. The proportion of patients with systolic HF, as well as the presence of numerous comorbidities are in line with previous studies [5,23]. As a result, our study can be considered fairly representative of the Spanish population.
With regards to HF therapies, approximately two thirds of patients were taking renin angiotensin system inhibitors and beta blockers, nearly one third aldosterone antagonists, and only 8.5% sacubitril/valsartan. The optimization of treatment of patients with HF is necessary not only to improve functional class and quality of life, but also to reduce morbidity and mortality [1,2]. These numbers are lower than those reported in HF units, but in line with those from other clinical settings [24,25]. This is very relevant, as the underuse of evidence-based HF medication is associated with a higher use of healthcare resources, particularly first and recurrent hospitalizations [26].
During the period 2015-2019, patient cumulative cardiovascular disease hospital mean cost reached 11,649 Euros. Importantly, cardiorenal hospitalizations were the most important contributor for the total cost, particularly HF hospitalizations. Overall, HF hospitalizations represent 1-2% of total admissions [7,27] and HF is the most common diagnosis in elderly hospitalized patients [28]. During the first year after diagnosis of HF, approximately half of the patients may be expected to be hospitalized at least once. In addition, readmission rates are high [7,29-31]. Of note, it has been reported that in Spain, rates of first hospitalization due to HF continue to increase, with high mortality [31]. A recent systematic review analyzed 16 cost-of-illness studies related to HF. Although there were large variations concerning cost components, the majority of them showed that hospital admission costs were the most expensive cost element. Annual costs for HF patients ranged from 868 Dollars (≈774 Euros) for South Korea to 25,532 Dollars (≈22,760 Euros) for Germany [3]. Other systematic review focused on economic HF burden also showed that hospitalization cost was found to be the main cost driver to the total health care cost and that the HF annual cost ranged from 908 Dollars (≈809 Euros) to 40,971 Dollars (≈36,522 Euros) per patient [12]. In our study, during the 2015-2019 period, HF associated costs per patient reached 15,373 Euros, in line with these studies. However, among other factors, methodological heterogeneity and specific cost items (including treatments) accounted for in the estimations indicate that cost comparisons across publications should be made with caution [32]. Certainly, all these data confirm the high cost burden of HF.
As the most important contributor for HF cost is HF hospitalizations, the use of those drugs that have demonstrated to be beneficial in this clinical context may be very helpful in reducing total HF cost. Thus, in 2014 the PARADIGM-HF trial showed that compared with enalapril, sacubitril/valsartan significantly reduced the risk of HF hospitalization by 21% and this might have had a positive impact [9]. In our study, from 2015 to 2019, in general there was a progressive reduction of cardiovascular disease hospital cost per year, as the proportion of hospitalized patients decreased. Of note, there was only a slight increase in HF medication cost per year which is a small contributor for total HF cost. This is in line with previous studies that have shown a decline in standardized HF hospitalization rates in Europe and United States [33,34]. However, absolute numbers of HF hospital admissions are expected to increase by about 50% in the following years due to the ageing of the population [7]. As a result, new drugs are needed to improve these numbers. In 2019, the DAPA-HF trial showed that in addition to recommended therapy, dapagliflozin significantly reduced the risk of a first worsening HF event by 30% [10]. Therefore, it can be hypothesized the addition of dapagliflozin to standard HF therapy may contribute to reduce HF costs.
Other contributors to total HF cost included primary care visits, specialized visits, and diagnostic tests. It has been reported that a better integrated hospital primary care HF program is associated with a significant reduction of readmission for HF and mortality [35]. In addition, moving to case management at home rather than outpatient cardiology clinic follow-up may also reduce healthcare costs [36]. Therefore, transition to an integrated management of HF patients is necessary to reduce HF burden.
A recent meta-analysis estimated the 1, 2, 5 and 10-year survival to be 87%, 73%, 57% and 35%, respectively, among HF patients [37]. HF hospitalization is an independent predictor for increased HF mortality [7,29,30]. In our study the proportion of patients who died decreased from 9.4% in 2015 to 4.9% in 2019, in line with the decrease in hospitalization rates. Although there is much room for progress, it is likely that the improvement in HF management during these years may have had a positive impact.
A specific analysis was performed in the DAPA-HF like population. In the DAPA-HF trial, the addition of dapagliflozin resulted in a significant reduction of HF hospitalizations, death from cardiovascular causes, and death from any cause, regardless the presence of diabetes [10]. In our study, in the DAPA-HF like population, all patients had reduced left ventricular ejection fraction HF and the majority of patients were on NYHA functional class II or III. Compared with the overall HF population, patients were taking more renin angiotensin system inhibitors and beta blockers. Although in these patients there was a decrease of patients hospital mean cost for year, these were higher than in the overall HF population. Thus, cumulative cardiovascular disease hospital cost reached 13,775 Euros (vs 11,649 Euros in the overall HF population). The great burden for this cost was due to cardiorenal hospitalizations (87.7% of the total hospital cost), particularly HF (65.9% of the total hospital cost). Therefore, to reduce HF cost burden in the DAPA-HF like population is of utmost importance to improve the HF management. As the great majority of these patients were taking renin angiotensin system inhibitors and beta blockers, the prescription of newer HF drugs, such as dapagliflozin, could be of particular benefit in the reduction of HF costs [10].
This study has some limitations that should be commented. This was an observational cohort study that used secondary data from electronic health records. As a result, only indirect causality can be provided. However, the high number of patients included, as well as the robustness of the data may allow to determine the value of the study. On the other hand, although data came from 7 Spanish regions, previous studies have shown that these data are representative of the Spanish population [18].