The German Lipid Apheresis Registry - remaining to be established

Lipoprotein apheresis standard for apheresis competence centers--an updated synthesis and amendment to pre-existing standards

With several techniques of selective apheresis treatment, some of which have been established for over 30 years, severe and pharmacologically unmanageable dyslipidemia can be treated successfully. The long-term lowering of LDL cholesterol and lipoprotein(a) by 60-80 percent, together with pleiotropic effects, allow for significant risk reduction in otherwise progressive chronic atherosclerotic disease, i.e. chronic coronary artery disease in most apheresis patients, and improvement of quality of life. For various reasons, worldwide only an estimated 2500 patients, among them 1400 to 1500 in Germany, are regularly treated by apheresis. This relatively small number of apheresis patients in Germany is being cared for in more than 200 centers, by more than 750 physicians approved for extracorporeal treatment, resulting in unraveling of expertise and diversity of treatment strategies instead of the needed concentration. Here we present a comprehensive standard for competence centers in apheresis treatment, which is an updated synthesis and amendment to previously published standards, based on the experience from more than 30,000 apheresis treatments in our own center. The presented standard provides a guideline for apheresis treatments, comprising all procedures, indications, detailing the application procedure, as well as suggestions for supportive care in extracorporeal therapy. In the absence of large studies of sufficient quality, this standard represents our "good clinical practice" and refers the "best available evidence", providing the indispensable basis for working in an apheresis center. The apheresis standard also aims to contribute to quality assurance, another intention is to increase the acceptance of this valuable treatment, with a view to admitting more patients in need to apheresis programs, on the basis of reliable cost reimbursement.

Current view: indications for extracorporeal lipid apheresis treatment

Background

One of the first investigations concerning extracorporeal treatment of hypercholesterolemia was performed in 1967 by plasma exchange in patients with homozygous or severe heterozygous familial hypercholesterolemia (FH). In the following decades, several specific lipid apheresis systems were developed to efficiently eliminate low-density lipoprotein (LDL) cholesterol and Lp(a) cholesterol in hypercholesterolemic patients. In the early 1980s, the main clinical indication has been homozygous FH including mainly children and pregnant women. In consideration of the current development of lipid-lowering regimens and scientific knowledge of preventing progression of cardiovascular diseases, the spectrum of indications to initiate lipid apheresis was extended due to still insufficient lipid-lowering therapy in some clinical cases. However, a generally accepted indication for lipid apheresis treatment is still under discussion. In Germany, the target-oriented distribution of increasingly limited healthcare resources demand data which support the benefit of established treatment procedures such as lipid apheresis. In recent years, the Federal Joint Committee (G-BA), a paramount decision-making body of the German Healthcare System, issued to reassess the approval of chronic lipid apheresis therapy for regular reimbursement. Therefore, in 2005, an interdisciplinary German Apheresis Working Group has been established by members of both the German societies of nephrology. One of the first goals of this working group was a revision of the indications for lipid apheresis corresponding to current guidelines and recommendations for the treatment of lipid disorders. In addition, recently new pathophysiological perceptions of the impact of lipoproteins on atherogenesis and thrombosis were also considered.

Methods and Results

Since 2005, the working group met on a regular basis to substantiate the first defined goals. The indications for lipid apheresis were critically revised with respect to actual results from clinical investigations, cardiovascular guidelines, and scientific knowledge and were accepted by the members of the apheresis working group.

Conclusions

There is consensus between the medical societies and health insurance funds regarding the need for general accepted guidelines for lipid apheresis. Recommendations for the indications of lipid apheresis were developed, but additionally these results should be confirmed by medical societies to transform them to guidelines. However, due to limited data showing that lipid apheresis has effects on the progression of cardiovascular diseases all members of the apheresis working group support a project for creating a lipid apheresis registry. This apheresis registry has been developed and recently started. The primary goal is to substantiate prospective long-term data on clinical outcome of chronic lipid apheresis treatment and to support additional clinical research activities in this field. In addition, this registry should comply with the actual requests of the Federal Joint Committee (G-BA).

HELP apheresis in hypercholesterolemia and cardiovascular disease: efficacy and adverse events after 8,500 procedures

Introduction

Low density lipoprotein (LDL-C) apheresis is a last treatment option for hypercholesterolemic patientsresistant to conservative lipid-lowering therapy. In a retrospective analysis of 8,533 heparin-induced extra-corporeal LDL precipitation apheresis treatments (HELP), we evaluated the efficacy of LDL reduction, the rate of adverse events, and the progression of atherosclerosis.

Methods

Between July 1992 and April 2009, we performed 8,533 HELP apheresis therapies in patients with familial hypercholesterolemia (FH). Inclusion criteria were FH with insufficient lipidological status under optimal drug therapy and diet, and at least 50 HELP therapies. Left ventricular function and valvular status was checked prior to the first apheresis therapy and at the end of the individual HELP program. Blood samples were taken directly before and after each therapy. Blood count, electrolytes, total cholesterol, LDL–C, high density lipoprotein (HDL–C), triglycerides, lipoprotein (a) (Lp(a)), and fibrinogen were measured. Adverse events were documented weekly.

Results

We evaluated 27 patients (19 men) with FH (age 49.2 ± 12.5 years (range 10–67 years)). The number of HELP treatments once weekly was between 50 and 790 applications. Mean follow-up time was 7.0 ± 5.2 years (range 1.3–16.6 years).

Prior to the individual apheresis program, 44.4% of the patients had a three vessel disease (VD; 25.9% two VD, 25.9% one VD) and 7.4% had a peripheral arterial occlusive disease. During the time of HELP treatment, none of the patients had a myocardial infarction; 3.7% had one percutaneous coronary intervention (PCI), 11.1% two PCI, 14.8% three PCI, 11.1% ³ four PCI.

The patients received 1.2 ± 1.6 (range 0–5) PCI during follow-up time. Adverse events directly associated with HELP therapy were very rare (< 3%). Mean elimination of LDL-C was 63.49 ± 7.1%.

Discussion

The HELP apheresis therapy was well accepted by the patients in our programs. Adverse events during HELP apheresis were rare. This data is in line with the experiences published by other authors who reported an adverse event rate of 3.6% in adults. The LDL-HDL ratio, one of the strongest predictors of premature CHD events, improved significantly during the apheresis program.

Conclusion

HELP is a safe, comfortable, and highly effective treatment in which adverse events are rare. It can reduce the burden of atherosclerosis, with no myocardial infarction and a low coronary intervention rate in our patients.

Role of lipid apheresis in changing times

During the last decades, LDL-apheresis was established as an extracorporeal treatment option for patients with severe heterozygous or homozygous familial hypercholesterolemia (FH) that is resistant to conventional treatment strategies such as diet, drugs, and changes in lifestyle. Nearly half a century ago, the first LDL-apheresis treatment was performed by plasma exchange in a child with homozygous FH. At the beginning of the 1970s, the clinical advantage of regular extracorporeal LDL-elimination was demonstrated in siblings suffering from homozygous FH. These findings encouraged researchers especially from Germany and Japan to develop extracorporeal devices to selectively eliminate LDL-cholesterol in the 1980s. Although the selectivity of the currently available LDL-apheresis devices is different, the efficacy of LDL-elimination during a single treatment is rather similar and ranges between 55 and 65 % of the pretreatment LDL plasma concentration.In the 1990s, the patients regularly treated by extracorporeal LDL-elimination, diet, and drugs were included in regression studies assessed by angiography. It was shown that the combined treatment with LDL-apheresis, diet, and drugs resulted in less progression of coronary lesions than drugs and/or diet alone. However, although a tendency was evident, results did not reach criteria for significance. During the last decade, apheresis registries were established to collect data on efficiency, safety, and clinical outcome of regular long-term LDL-apheresis. The evaluation of registry data will certainly permit further insights in the therapeutic benefit of this expensive and time-consuming therapeutic approach. Furthermore, the future of LDL-apheresis will depend upon the availability of highly efficient new drugs and molecular genetic approaches such as RNA silencing of the apoB gene, whereas the liver transplantation and gene therapy of the LDL-receptor deficiency will not replace LDL-apheresis in severe familial hypercholesterolemia in the near future.

Lipoprotein apheresis

PURPOSE OF REVIEW

Lipoprotein apheresis is being performed with increasing frequency, but better data collection and recording of clinical outcomes are needed. Setting up registries would facilitate this process.

RECENT FINDINGS

This review appraises recent articles that discuss the need for national registries and requirements for setting them up, the efficacy of lipoprotein apheresis in homozygous familial hypercholesterolaemia and patients with coronary disease secondary to raised levels of lipoprotein (a), and its role in the management of acute pancreatitis secondary to severe hypertriglyceridaemia.

SUMMARY

Lipoprotein apheresis seems to be going through a growth spurt, presumably reflecting better implementation of treatment guidelines or a broadening of indications for its use.