Causes of differences in the uptake of cardiac implantation electronic devices in Slovenia in comparison to other countries

The use of medical devices in the field of electrophysiology or cardiac implantation electronic devices (CIEDs) affects a large number of patients and contributes significantly to health expenditure (1,2,3). However, the uptake of CIEDs proved to vary across countries (4).In this paper, we investigate the causes of the differences in pacemakers (PMs) and automatic implantable cardioverter-defibrillators (ICDs), based on the results of the analysis of administrative hospital discharge (HD) databases in five European nations (Austria, England, Germany, Italy and Slovenia) over five years (2008-2012), performed in the frame of MedtecHTA project. Moreover, to further validate the statistics, the data from national registries were compared to figures published in the European Heart Rhythm Association - EHRA White Books. This finding has motivated the present study.

The goal of the article is to analyse and present the causes of the differences in crude utilisation rate in medical devices, specifically PMs and ICDs, among studied countries, as reported in HD databases of respective countries, with a specific emphasis on Slovenia. The research was focused on the selected CIEDs because of three salient characteristics of the devices used in this field, namely: a) randomised clinical trials for some devices have produced significant outcome measures (for some of these devices there is strong evidence of efficacy for specific indications); b) they represent a significant outlay of resources and, given high implantation rates, contribute to increases in the overall health expenditure; c) they have induced relevant organisational changes as they often require more multidisciplinary expertise in patient management.

Comparisons of administrative HD data at the international level and analyses of utilisation rates of CIEDs across countries are rare and great effort was invested to assure their comparability. This empirical exercise has been carried out in the framework of MedtecHTA project. As it proved, final results could not fully overcome the national differences and our aim is to further investigate some of these differences through interviews with Slovenian experts in the field. However, as our qualitative research derives from the mentioned empirical work, we should first present it properly.

The findings of this study will provide insight into the data evidencing and collecting, indicate the potentials of using administrative databases in health policy and decision-making as well as give an overview of the researched topic.

Returning to the presentation of MedtecHTA empirical results (5), the comparison of data on the use of ICDs and PMs, obtained from HD databases, across 5 countries, from 2008 to 2012, showed very high crude utilisation rate in Germany, followed by Italy, England and Austria, and very low crude utilisation rate in Slovenia in PM implants as well as in ICD implants (for details see Table 1 in Appendix).

A threefold lag in PM implants and fourfold lag in ICD implants utilisation of Slovenia behind leading Germany rate can be noticed. The comparison of the annual average increase in utilisation rate in pacemakers from 2008 to 2012, across countries, shows the lowest growth rate in Italy, where the utilisation rate is already high, followed by Austria, Slovenia and Germany, with growth rates from 1.84 to 2.54, and the highest increase in England, where the annual growth rate in 4 years was 11.91%. In ICD implants the growth rate is generally higher due to the fact that ICD technology is more demanding and newer. The growth rates range between 3.17 in Italy and 14.42 in Slovenia, where the starting point of crude utilisation rate in 2008 was much lower.

To validate the data on crude utilisation rates obtained from hospital DRG database, the data were compared to figures published in the EHRA White Book (6). The comparisons showed fairly similar numbers for some countries, but disagree on totals for PM in Slovenia by as much as 100%. There were also differences in other categories, yet not that large (for details see Table 2 in Appendix).

Analysing the differences in the uptake of CIEDs across the countries shows there are differences in usage according to the age groups and gender (see Figure 1 in Appendix). The ICDs implementation rates in the highest age group almost level up with the previous age group for male, while considerate decline can be observed in case of female patients in all five countries. Regarding PMs, it is evident that Austria, England, Germany and Italy have quite similar implementation rate patterns across age groups, while in Slovenia the implementation rates of PMs in the age groups 65-74 years and over 75 years are almost twice lower than in other countries. On the other hand, much smaller differences between countries can be observed in the age groups 0-44 years and 45-64 years. Regarding gender, the ratio of PM uptake in men and women in all studied countries is approximately 2:1, while a much wider gap between male and female can be observed in ICDs. Namely, implementation rates of ICDs in all five countries are almost four times higher for men than for women. These gender inequalities are most prominent in the age groups 65-74 years and over 75 years.

Analysis using the Charlson Comorbidity Index (CCI) methodology was used to investigate the types and severity of diseases observed among patients treated with PM/ICD (for details see table 3 in Appendix). The disease categories that were most evident among patients with implants were acute myocardial infarction (AMI), congestive heart failure and diabetes. The presence of these diseases was measured as the percentage of all hospitalizations where one of the CCI disease codes was observed in at least one of the primary or secondary diagnostic codes. Prevalence of AMI is highest for PMs and ICDs in Germany, followed by Slovenia and Italy. The comorbidities are very low in Austria, but the data are not realistic as Austrian database only has one possible field available for diagnosis coding. Congestive heart failure is present in 32% of PM implanted patients in Germany, followed by 23% in Slovenia with England and Italy at 15% and 13%, respectively. In ICDs the prevalence of AMI is much higher than in PMs, again highest in Germany, followed by Slovenia.

To find out the possible reasons for such high differences in CIEDs utilization data (between different data sources and across different countries) a qualitative research study was adopted using in-depth interviewing as a data collection technique. The main purpose of the interviews was to find possible answers to explain and understand the underlying differences in the results that were generated in the analysis of administrative HD database.

Results of the interviews were organized according to the four scenario sections. In the first section, considering the coding of implanted CIEDs and related procedures as a reason for differences in data, the first reason explaining the differences is diagnosis related groups (DGR) coding system that was valid until December 21, 2012 in which no codes for PM replacement existed. As the hospitals did not have a possibility to enter the code for PM replacements, they used different ways to approach the issue. Some of them did not code the procedure at all and some of them coded it as “unspecified PM first implant”. Furthermore, some codes in the old coding system (38253-01 to 38253-10; insertion of permanent single/dual chamber PM) were only valid until December 31, 2010, which means that these procedures were then evidenced under various other codes.

The coding of ICDs is better managed mostly due to the low number of centres in Slovenia that perform ICD surgeries (2 centres) and the codes exist for all the ICD procedures. The difference between the number of procedures in HD database and EHRA database was hence not that large (ICD category includes also CRT-D procedures, so altogether the numbers for ICD are quite correct, although not dispersed across various subcategories within ICDs). However, the codes were again not specific enough: there were no codes to indicate the use of the four types of device (single chamber, dual chamber, BV/ CRT and unspecified) as Australian coding system is not specific enough (e.g. there is no code for CRT_P or CRT_D procedures and according to one of the interviewees “all such procedures are coded under ICD which is wrong”).

The next reason referred to the low interest in proper coding. It was stated in the interviews that the interest for proper coding is not there as it represents only additional administrative work for the coder nurse. The hospitals are not paid entirely according to the DRG system in Slovenia, which means that lack of motivation for proper coding is present. According to the interviews we could conclude that the data that we obtained from HD database are less reliable and accurate than the data that are submitted to EHRA, in which physicians take their professional interest and pride in submitting.

While the two above mentioned reasons refer to data inaccuracy and incomparability, third obvious reason for the differences in the implantation of CIEDs among studied countries, as conveyed by the respondents, is that no golden rule for optimal crude utilization rate exists. According to the respondents in the interviews conducted there is “no golden rule, which would define the optimal crude utilization rate”. “In Italy the number of implants seems too high, PMs are implanted into patients who do not need implant. Italy, as well as Germany, is obviously confronted with the phenomenon of overtreatment, which is a consequence of having numerous private implementation centres”. “England, on the other hand, is not the best country to base comparisons on as the system is too strict and restricted with high demands for savings.”

Clearly, as the last reason for the differences, the respondents conveyed the conviction of economic reasons playing a role in the implantation rate. If there was reasonable doubt about the necessity and/or benefits of a CIED, Slovene cardiologists would rather wait and postpone implantation, especially in the case of ICDs being more expensive, which may explain a substantial lag of Slovenia behind other economically more developed countries. According to respondents, other differences among countries such as clinical guidelines, incidence and prevalence do not play a role in explaining observed differences in crude utilization rates of CIEDs. However, any further analysis on the differences in uptake of PM and ICD due to factors such as economic development measured by GDP is not possible as the data provided in Slovene HD database are too unreliable due to reasons cited above (underreporting, data inaccuracy and incomparability).

The interviewees explained that the policy regarding ICDs implants is very restrictive due to their high price, especially in elderly over 80 years of age. Indications for the ICD implants are very strict, the patients need to be in good condition and their medical states have good prognoses (hence one could expect higher utilization rates for women, especially in ICDs, due to longer life-expectancy; however, the results are just the contrary). Comorbidities are important factor in decision making. As elderly often have lots of comorbidities, this might explain the stagnation or a slight decline in implants crude rates in the oldest age group. One of the interviewees explained that “in Slovenia ICDs are generally not implanted in patients with life expectancy up to maximally one year as this would not be justifiable for the insurance”. “In Germany, on the other hand, which has the highest implementation rate for ICDs in the oldest age group, the high ICD crude rate is the consequence of numerous private insurance policies which cover these procedures that the public insurance would not want to cover anymore – due to higher risk in older patients with many comorbidities.” “The implantation of ICD in high age and in patients who do not have good prognoses would mean an agony for the patients and their relatives as the ICD would react non-stop”. “Regarding the youngest group of patients in Slovenia, implanting of ICD and PM is very restrictive. If the implants are inserted in young age heart’s condition deteriorates with all the replacements as some electrodes cannot be pulled out, which can cause heart failure. So the age plays an important role in the youngest (up to 44 years of age) and oldest (80+ years of age) patients.” The main reasons for differences in data on CIEDs uptake across studied countries are summarised in Table 1.

Table 1

Main reasons for difference in data in CIEDs uptake in 5 European countries (2008-2012).

According to the interviewees, at least in Slovenia, the patients who are candidates for PMs and ICDs are carefully screened and “only those with absolute indication” receive the implant. Although there is no economic limitation for CIED implantation when medically indicated, the patients in Slovenia are in a worse baseline health state, in comparison to other countries (except Germany), as confirmed by Charlson Comorbidity Index (see Table 3 in Appendix).

The correlation between CIEDs implants and AMI or other heart conditions seems reasonable according to one of the interviewees: “AMI is the reason the patient has received an ICD in the first place.” Diabetes prevalence rates in ICD and PM patients do not differ much. Regarding diabetes, one needs to be aware of the fact that there is no direct linkage to CIEDs. According to one of the interviewees, “diabetes is not a single predictor of CIEDs implants, as it strongly correlates with AMI”.

The overall CCI weighted scores indicate the relative health state of patients receiving both types of devices, and serve mainly to illustrate whether patients receiving a certain type of CIED have a higher or lower average CCI weighted score. Slovenia and Germany do implant less healthy patients. This can be due to economic restrictions, as presumably is the case in Slovenia. The high CCI score in Slovenia would mean a carefully implemented restriction on the implant use, especially in ICDs. The ICDs are expensive and their use is carefully considered, ICDs would only be implanted in patients with absolute indications. In Germany, such a high CCI score could be interpreted as the possibility to implant very weak and older patients as well, which is possible especially due to a high number of private clinics, where the implantations are undertaken.

Based on our qualitative analysis, it can be observed that the largest differences in Slovenian HD and EHRA data are the consequences of the DRG coding system and coding practices (e.g. ambivalence in coding and data inaccuracy). The DRG coding system that was valid until 21 December 2012 contained no codes for PM replacement. As a result, the hospitals used various approaches to code their work. The coding of ICDs in Slovenia is better managed mostly due to the low number of centres that perform ICD surgeries and the fact that the codes exist for all the ICD procedures. However, they are still not specific enough. Consequently, until 2013, HD database had limited analytical value (7).

Coding practices are irrevocably connected to the system of financing health care: it is of utmost importance to implement the HD system fully in Slovenia, and use ARDRG 6.0 version for payments to providers.

The analysis of differences in the uptake of CIEDs according to gender and age shows similar trends across five analysed countries. Specifically, for Slovenia, more strict indications for implanting ICDs as well as PMs can be observed. The differences can be observed in ICD implants in elderly male group, where the implant rate continues to increase in some countries, but decreases in Slovenia and Austria. Interestingly, the implant rates in females decrease in all countries. Such a decrease in both genders in the oldest age group of patients, particularly in Slovenia, can be attributed to the combination of factors: savings, careful examination of the health status and life expectancy of a patient, and to weighting the pros and cons of ICD implants. The ratio for ICDs between both genders is even 4:1 in favour of male patients and the ratio equally persists in all five investigated countries. Similarly, surprising results regarding the gender differences have also been found in previous large-scale studies (8, 9). The authors of these studies claim that observed gender disparities could not be attributable to different heart failure prevalence across gender, different proportions of male and female subgroups in study samples, or to any other similar contextual factors, which might indicate that cardiologists adhere to different standards and/or guidelines while treating either male or female patients. Unfortunately, the present study cannot provide a solid explanation for the observed gender inequalities, as this was not the prime objective of our research. Further research would be required to investigate the reasons behind different crude utilisation rates for CIEDs in male and female patients.

The interviewees had various explanations for observed differences in comorbidities across countries: one possible explanation is that some countries decide to use implants much earlier than others do, even when patients are in relative need or when patients are older or weaker, which can depend on the system (private vs. public) and resources available.

The comparison of crude utilisation rates of CIED uptake across 5 European countries between 2008 and 2012 revealed a substantial lag of Slovenia behind other developed countries. Several potential reasons for such a discrepancy have been explored and identified in the literature, including coding practices (and, consequently, data inaccuracy), economic factors, hospital and regional differences and evidencing as well as different adherence to clinical guidelines (10, 11). The results have been mixed on how and how much economic factors affect access to technologies such as PMs and ICDs (11, 12). It is difficult and too simple to attach the difference to economic factors and development (GDP) of the countries entirely. To better differentiate between administrative peculiarities, malfunctions or incompleteness of the system of evidencing CIEDs, health care system financing and factors like variations in clinical guidelines or lack of access to CIEDs due to economic factors, the research results of MedtecHTA project were topped up by interviews with cardiologists and administrative personnel in Slovenia. First, the available data from Slovene HD database have been proved incorrect and hence unreliable, especially in the segment of PMs uptake due to several reasons (incomplete coding system, lack of interest and motivation for proper coding as financing is not directly linked to the number of CIEDs actually being implanted, etc.). In other words, the comparison of HD database with EHRA database has shown that almost one half of PM implants are not reported in the Slovene HD database, while the discrepancy in the number of ICD implants in both databases is smaller. Observed disparities in case of PM implants can be attributed to the problem of underreporting. Doubling crude utilisation rates for PM implants in Slovenia would substantially reduce discrepancies across countries. However, Slovenia would still remain a country with the lowest crude utilisation rates. Underreporting surely plays a major role, but it is definitely not the only reason for low PM implant rates. The physicians claimed that clinical guidelines and protocols used do not vary across countries.

Data on ICD implants, on the other side, is more reliable. In case of ICD implants, the lowest crude utilisation rate in Slovenia can be interpreted primarily in the context of economic factors. As ICDs are much more expensive than PMs, patients are carefully scanned for absolute indications, taking into account the health status and patient’s life-expectancy. In case of doubt and/or relative indications, a patient would normally not receive the implant, which is not necessarily the case in other developed countries with numerous “high volume centres” and extensive private insurances that cover procedures that public insurance would not approve. Financial deficits in economically less developed countries, however, do not impose different clinical guidelines regarding the treatment of patients with heart failure and related conditions. Those with absolute indications would definitely receive a proper CIED, but due to financial restrictions, practitioners are expected to be more stringent in case of relative indications. Such restrictions, on the other hand, also impose protection for patients, as the rather invasive CIEDs are not implanted regardless of the costs/benefits for the patients, but with careful consideration and only in absolute need. This also contributes to the prevention of the overuse of ICDs, which might have considerate negative impacts on health and life-quality if decisions are not in line with professional standards.

To sum up, it can be concluded that economic development (e.g. measured in GDP per capita) to a certain extent predicts the crude utilisation rates of CIEDs; however, the size of the effect is hard to identify as the available data in HD database is incomplete and unreliable. Hence, we recommend the following: (a) to implement the coherent DRG system in all hospitals, with claims for concise and consistent reporting and the need to establish transparent linkage between coded procedures and financial reimbursements; (b) to continuously monitor the advances in the field of CIED development and innovation, and to update the DRG codes regularly so as to avoid delays that would hinder the quality of reported data and realistically reflect the work performed.

Moreover, MedtecHTA project revealed some interesting results regarding gender inequalities in CIEDs utilisation rates, which persist in all 5 studied countries and cannot be fully explained. We recommend designing an additional in-depth research to uncover the reasons for the observed differences between male and female patients, primarily in those being older than 64 years, where largest discrepancies have been identified.