Binding and detoxification efficiency of albumin decline after haemodialysis.

BACKGROUND: Albumin, as the most abundant plasma protein, represents a target structure for both drug and physicochemical therapeutic approaches to eliminate uraemic toxins more efficiently. Potentially, this approach could reduce mortality of haemodialysis patients. However, little is known about albumin functional properties in these patients and its alteration by haemodialysis treatment. METHODS: The binding and detoxification efficiency of albumin were assessed by electron paramagnetic resonance spectroscopy using a spin-labelled fatty acid. Binding efficiency (BE) reflects strength and amount of bound fatty acids under certain ethanol concentration. Detoxification efficiency (DTE) reflects the molecular flexibility of the patient's albumin molecule, thus the ability to change the conformation depending on ethanol concentration. Percentage of BE and DTE are depicted in relation to healthy individuals (100%). RESULTS: Fifty-eight patients (59% male, median age 68 years, median time on haemodialysis 32 months) were included in the study. Before haemodialysis treatment, albumin binding and detoxification efficiency were substantially below healthy individuals [median BE 52% (interquartile range, IQR, 45%-59%); median DTE 38% (IQR 32-49%)]. After haemodialysis treatment, median BE and DTE significantly decreased [BE 28% (IQR 20-41%); DTE 11% (IQR 7%-27%; P < .001)]. BE and DTE decline after haemodialysis was not dependent on age, sex or treatment modalities, but was to a certain extent on the level of non-esterified fatty acids. CONCLUSION: Albumin binding and detoxification efficiency of fatty acids in maintenance haemodialysis patients were substantially below those in healthy individuals and even declined after dialysis treatment. These findings might be helpful when considering new therapeutic approaches in maintenance haemodialysis patients.

Albumin redox state of maintenance haemodialysis patients is positively altered after treatment.

BACKGROUND AND AIM: Maintenance haemodialysis patients have increased morbidity and mortality which is mainly driven by an elevated inflammation level due to the uraemic milieu. A major part of this increased inflammation level is the degree of oxidative stress which can be assessed by albumin redox state (ARS). Aim of this study was to evaluate how the ARS is affected by a haemodialysis treatment and different dialyzer properties. METHODS: ARS was determined before and after haemodialysis treatment by fractionating it into reduced human mercaptalbumin (HMA), reversibly oxidized human non-mercaptalbumin 1 (HNA-1), and irreversibly oxidized human non-mercaptalbumin 2 (HNA-2) by high-performance liquid chromatography. In healthy individuals, albumin circulates in the following proportions: HMA 70-80%, HNA-1 20-30% and HNA-2 2-5%. High flux (FX 100 [Fresenius Medical Care], BG 1.8 [Toray], Xevonta Hi 18 [B. Braun], CTA-2000 [Kawasumi]) and low flux FX10 [Fresenius Medical Care] dialyzers were used. RESULTS: 58 patients (59% male, median age 68 years, median time on haemodialysis 32 month) were included in the study. Before haemodialysis treatment, HMA (median 55.9%, IQR 50.1-61.2%) was substantially lower than in healthy individuals. Accordingly, oxidized albumin fractions were above the level of healthy individuals (median HNA-1 38.5%, IQR 33.3-43.2%; median HNA-2 5.8%, IQR 5.1-6.7%). Before haemodialysis treatment HMA was significantly higher in patients usually treated with high flux membranes (p < 0.01). After haemodialysis treatment there was a significant increase of HMA and a decrease of HNA-1 and HNA-2 (p < 0.01). These effects were more pronounced in patients treated with high flux dialyzers (p < 0.01). There were no differences of ARS alteration with regard to the dialyzer´s sterilization mode or the presence of diabetes. CONCLUSION: The study confirms that the ARS is positively altered by haemodialysis and shows for the first time that this effect depends on dialyzer properties.

Predictive role of fluctuating biochemical parameters for mortality in hemodialysis patients.

INTRODUCTION: High inflammation parameters like C-reactive protein and low albumin levels are considered as risk factors in CKD stage 5 patients. Due to dynamic changes in these parameters, there is evidence of an association between their variation and mortality in hemodialysis patients. METHODS: We retrospectively analyzed 153 patients on chronic hemodialysis. Dialysis-specific biochemical parameters were measured at three-month intervals over a 42-month period. Fluctuations were calculated as the percentage change in two subsequent measurements. RESULTS: Median age was 70 years. 41.10% of the patients died over the study period. Higher fluctuation rates in albumin and CRP were significantly associated with a higher mortality rate. Regression analysis revealed that only the fluctuations in albumin proved to be a predictive variable for the end point "death." If the fluctuation in albumin increases by 1%, the mortality risk rises by 22%. CONCLUSION: Fluctuations in albumin are of predictive importance in patients on chronic hemodialysis.

Cardiovascular Outcome of Pediatric Patients With Bi-Allelic (Homozygous) Familial Hypercholesterolemia Before and After Initiation of Multimodal Lipid Lowering Therapy Including Lipoprotein Apheresis.

Twenty-four patients with bi-allelic familial hypercholesterolemia commencing chronic lipoprotein apheresis (LA) at a mean age of 8.5 ± 3.1 years were analysed retrospectively and in part prospectively with a mean follow-up of 17.2 ± 5.6 years. Mean age at diagnosis was 6.3 ± 3.4 years. Untreated mean LDL-C concentrations were 752 mg/dl ± 193 mg/dl (19.5 mmol/l ± 5.0 mmol/l). Multimodal lipid lowering therapy including LA resulted in a mean LDL-C concentration of 184 mg/dl (4.8 mmol/l), which represents a 75.5% mean reduction. Proprotein convertase subtilisin/kexin type 9-antibodies contributed in 3 patients to LDL-C lowering with 5 patients remaining to be tested. After commencing chronic LA, 16 patients (67%) remained clinically stable with only subclinical findings of atherosclerotic cardiovascular disease (ASCVD), and neither cardiovascular events, nor need for vascular interventions or surgery. In 19 patients (79%), pathologic findings were detected at the aortic valve (AV), which in the majority were mild. AV replacement was required in 2 patients. Mean Lipoprotein(a) concentration was 42.4 mg/dl, 38% had >50 mg/dl. There was no overt correlation of AV pathologies with other ASCVD complications, or Lipoprotein(a) concentration. Physicochemical elimination of LDL particles by LA appears indispensable for patients with bi-allelic familial hypercholesterolemia and severe hypercholesterolemia to maximize the reduction of LDL-C. In conclusion, in this rare patient group regular assessment of both the AV, as well as all arteries accessible by ultrasound should be performed to adjust the intensity of multimodal lipid lowering therapy with the goal to prevent ASCVD events and aortic surgery.

Relapsing and Progressive Complications of Severe Hypertriglyceridemia: Effective Long-Term Treatment with Double Filtration Plasmapheresis.

BACKGROUND: Severe hypertriglyceridemia (HTG) is associated with major complications such as acute or relapsing pancreatitis (AP) and atherosclerotic cardiovascular disease (ASCVD). Rapid elimination of triglyceride (TG)-rich lipoproteins (LP) with double filtration plasmapheresis (DFPP) without need for substitution has been found to be effective for the acute, short-term treatment of HTG-induced AP. Data on the long-term use of DFPP to prevent HTG-associated complications are scarce. OBJECTIVES: To evaluate the use and efficacy of regular DFPP treatment in clinical practice for preventing recurrence of HTG-associated complications in thera-py refractory patients. METHODS: Retrospective multicenter study in patients with severe symptomatic drug and diet refractory HTG with regular DFPP treatment. Patients' incidence of HTG-associated pancreatic or cardiovascular complications was compared before treatment and with regular DFPP treatment. RESULTS: Ten patients (3 female) were identified with baseline maximal TG concentrations of 2,587-28,090 mg/dL (median 5,487 mg/dL; interquartile range [IQR] 4,340-12,636). The mean observation period was 3.9 ± 3.4 years before and 3.8 ± 3.0 years after commencement of DFPP. In 5 patients, severe HTG was related to chylomicronemia, 2 patients had familial partial lipodystrophy Dunnigan, and 1 patient had additional LP(a)-hyperlipoproteinemia. The main HTG-associated complication was recurrent AP in 8 patients, including 1 patient treated during pregnancy. Two patients presented severe progressive ASCVD. With long-term DFPP treatment, the annual rate of HTG-associa-ted pancreatic or cardiovascular complications declined from median 1.4 (IQR 0.7-2.6) to 0 (IQR 0.0-0.4; p < 0.005). The absolute number of events was reduced by 77%. In 6 patients (60%) episodes of AP did not occur, nor was progression of ASCVD detected clinically or by routine imaging techniques. DFPP was effective in the elimination of TG-rich LP from plasma, and was safe and well-tolerated. CONCLUSION: Long-term, regular DFPP treatment resulted in stabilization of patients with severe HTG and related recurrent AP or progression of ASCVD, who were refractory to conventional dietary and drug therapy.

Real-world study: Escalating targeted lipid-lowering treatment with PCSK9-inhibitors and lipoprotein apheresis.

INTRODUCTION: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition with monoclonal antibodies has complemented the armamentarium of lipid-lowering therapy (LLT) before the final step of commencing chronic lipoprotein apheresis (LA). Data are scarce on patients who, after escalation of LLT with PCSK9 antibodies, have commenced chronic LA or PCSK9 antibody treatment during ongoing long-term LA. PATIENTS AND METHODS: In this study, a cohort of 110 patients with established atherosclerotic cardiovascular disease (ASCVD) due to hypercholesterolemia or concomitant lipoprotein(a)-hyperlipoproteinemia, who received PCSK9 antibodies for the first time during routine care, were consecutively identified. RESULTS: Mean LDL-C concentration prior to initiation of LA or PCSK9 antibody treatment was 5.3 ± 2.6 mmol/L (205 ± 102 mg/dL). Due to established ASCVD, the risk-adjusted LDL-C target value was <1.8 mmol/L (<70 mg/dL) in all patients. Use of PCSK9 antibodies increased the proportion of patients attaining the LDL-C target concentration by 41.8% overall. Treatment emergent adverse events (TEAE) associated with PCSK9 antibody medication were reported in 35 patients (31.8%). Discontinuation of PCSK9 antibody therapy due to TEAEs occurred in 25 patients (22.7%). CONCLUSION: Finally, 55.5% of patients received a combination of PCSK9 antibody therapy and LA at individually optimized treatment frequencies resulting in an increase of target attainment in 54.1% of patients. About 18.1% of chronic LA patients terminated LA treatment in this real-world study. The termination of long-term LA therapy, which has hitherto prevented the progression of ASCVD, requires careful individual risk assessment and cannot be recommended by the general criteria of LDL-C reduction.

Multimodal lipid-lowering treatment in pediatric patients with homozygous familial hypercholesterolemia-target attainment requires further increase of intensity.

BACKGROUND: Familial hypercholesterolemia (FH) causes premature cardiovascular disease (CVD). Lipoprotein apheresis (LA) is recommended as first-line lipid-lowering treatment (LLT) for homozygous (ho) FH. METHODS: Efficacy of multimodal LLT including lifestyle counseling, drug treatment, and LA was analyzed in 17 pediatric hoFH or compound heterozygous (c-het) FH patients, who commenced chronic LA in Germany before the age of 18. RESULTS: At time of diagnosis, mean low-density lipoprotein cholesterol (LDL-C) concentration was 19.6 mmol/l (756 mg/dl). Multimodal LLT resulted in 73% reduction of mean LDL-C concentration including a 62% contribution of LA. Only three children (18%) achieved mean LDL-C concentrations below the recommended pediatric target of 3.5 mmol/l (135 mg/dl). In 13 patients (76%) during chronic LA, neither cardiovascular events occurred nor was CVD progression detected clinically or by routine imaging techniques. In four patients (24%), cardiovascular events documented progression of CVD despite weekly LA, including one death due to coronary and cerebrovascular CVD which was not stabilized after commencing LA. Based on the mutational status, only 6 out of the 17 children were candidates for proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibition. Two already responded with further LDL-C decrease by 40%. CONCLUSIONS: Next to drug therapy, regular LA is an essential component of LLT for approaching LDL-C targets in children with hoFH or c-hetFH, which was successful only in a minority of children. Progression of CVD morbidity and resulting mortality remain unresolved issues. Early and intensified multimodal LLT guided by risk factors beyond LDL-C concentration is needed to improve outcome.

Efficacy of lipid reduction with DALI and MONET.

BACKGROUND: Lipidapheresis techniques are increasingly used to treat drug-resistant hyperlipidemia but few efficacy studies under routine application are available. In this multicenter observational study we investigated direct adsorption of lipoproteins (DALI) and lipoprotein filtration (MONET) for the short and the long-term effects on lipid-lowering effects. METHODS: Data of 122 apheresis patients from 11 centers (DALI: n = 78, MONET: n = 44) were prospectively collected for a period of 2 years. Routine lipid measurements were evaluated (2154 DALI and 1297 MONET sessions). It was investigated whether the relative reduction of LDL-C during apheresis session achieves at least 60%. Also relative reduction of total cholesterol, HDL, triglyceride, and Lp(a) were analyzed. RESULTS: The relative reduction of LDL-C was at least 60%: DALI: 70.62%, 95% CI = [69.34; 71.90] and MONET: 64.12%, 95% CI = [60.79; 67.46]. Also triglycerides were reduced with both systems: DALI 38.63%, 95% CI = [33.95; 43.30] vs. MONET 57.68%, 95% CI = [51.91; 63.45]. Relative reductions of total cholesterol were in the range of 50% (DALI 95% CI = [46.49; 49.65] MONET 95% CI = [48.93; 55.26]) and of Lp(a) in the range of 65% (DALI 95% CI = [61.92; 65.83] MONET 95% CI = [63.71; 70.30]. HDL reduction was: DALI 15.01%, 95% CI = [13.22; 16.79] and MONET 22.59%, 95% CI = [19.33; 25.84]. For both devices treated patient plasma/blood volume and in case of DALI the use of the larger adsorber configurations (DALI 1000 and DALI 1250) were independent positive predictors of the relative reduction of LDL-C and of Lp(a). CONCLUSIONS: Both systems effectively improved lipid profile and reduced atherogenic lipids. The results point to the importance of the individualized application of these valuable therapies to achieve clinical targets.

Safety aspects of lipidapheresis using DALI and MONET - Multicenter observational study.

BACKGROUND: Lipidapheresis was introduced for intractable hyperlipidemia as a more selective therapy than plasma exchange aiming to enhance efficacy and limit side-effects. Although this therapy is regarded safe, multicenter data from routine application are limited. We investigated direct adsorption of lipoproteins (DALI) and lipofiltration (MONET) regarding the short and the long-term safety aspects. METHODS: This multicenter observational study prospectively evaluated 2154 DALI and 1297 MONET sessions of 122 patients during a period of 2 years. Safety parameters included clinical side-effects (adverse device effects, ADEs), technical complications, blood pressure and pulse rate. Also routinely performed laboratory parameters were documented. Analysis of laboratory parameters was not corrected for blood dilution. RESULTS: Overall 0.4% DALI and 0.5% MONET treatments were affected by ADE. Technical complications occurred in 2.1% and in 0.8% DALI and MONET sessions, respectively. The most frequent ADE was hypotension, and the majority of technical problems were related to vascular access. Both types of treatments led to a drop of thrombocytes in the range of 7-8%. Hematocrit and erythrocytes decreased only during the DALI treatments by about 6%. Leucocytes decreased during the DALI therapy (∼15%), whereas they increased during the MONET application (∼11%). MONET treatment was associated with a higher reduction of proteins (fibrinogen: 58% vs. 23%, albumin: 12% vs. 7%, CRP: 33% vs. 19% for MONET and DALI, respectively). Apart from severe thrombocytopenia in two DALI patients, changes of other parameters were typically transient. CONCLUSIONS: Under routine use the frequency of side-effects was low. Still, monitoring of blood count and proteins in chronic apheresis patients is recommended.