Removal of large middle molecules via haemodialysis with medium cut-off membranes at lower blood flow rates: an observational prospective study.

BACKGROUND: Online haemodiafiltration (OL-HDF) may improve middle molecular clearance in contrast to conventional haemodialysis (HD). However, OL-HDF requires higher convective flows and cannot sufficiently remove large middle molecules. This study evaluated the efficacy of a medium cut-off (MCO) dialyser in removing large middle molecular uraemic toxins and compared it with that of conventional high-flux (HF) dialysers in HD and predilution OL-HDF. METHODS: Six clinically stable HD patients without residual renal function were investigated. Dialyser and treatment efficacies were examined during a single midweek treatment in three consecutive periods: 1) conventional HD using an HF dialyser, 2) OL-HDF using the same HF dialyser, and 3) conventional HD using an MCO dialyser. Treatment efficacy was assessed by calculating the reduction ratio (RR) for ß2-microglobulin (ß2M), myoglobin, κ and λ free light chains (FLCs), and fibroblast growth factor (FGF)-23 and measuring clearance for FLCs. RESULTS: All three treatments showed comparable RRs for urea, phosphate, creatinine, and uric acid. MCO HD showed greater RRs for myoglobin and λFLC than did HF HD and predilution OL-HDF (myoglobin: 63.1 ± 5.3% vs. 43.5 ± 8.9% and 49.8 ± 7.3%; λFLC: 43.2 ± 5.6% vs. 26.8 ± 4.4% and 33.0 ± 9.2%, respectively; P <  0.001). Conversely, predilution OL-HDF showed the greatest RR for ß2M, whereas MCO HD and HF HD showed comparable RRs for ß2M (predilution OL-HDF vs. MCO HD: 80.1 ± 4.9% vs. 72.6 ± 3.8%, P = 0.01). There was no significant difference among MCO HD, HF HD, and predilution OL-HDF in the RRs for κFLC (63.2 ± 6.0%, 53.6 ± 15.5%, and 61.5 ± 7.0%, respectively; P = 0.37), and FGF-23 (55.5 ± 20.3%, 34.6 ± 13.1%, and 35.8 ± 23.2%, respectively; P = 0.13). Notably, MCO HD showed improved clearances for FLCs when compared to HF HD or OL-HDF. CONCLUSIONS: MCO HD showed significantly greater RR of large middle molecules and achieved improved clearance for FLCs than conventional HD and OL-HDF, without the need for large convection volumes or high blood flow rates. This would pose as an advantage for elderly HD patients with poor vascular access and HD patients without access to OL-HDF. TRIAL REGISTRATION: Clinical Research Information Service (CRIS): KCT 0003009. The trial was prospectively registered on the 21 Jul 2018.

Association between non-alcoholic fatty liver disease and coronary calcification depending on sex and obesity.

Non-alcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome and is associated with cardiovascular outcomes. We investigated whether NAFLD was associated with coronary artery calcification (CAC) in participants without a previous history of cardiovascular disease and whether this association differed according to sex and obesity status after adjustment for other atherosclerosis risk factors, alcohol intake, and liver enzyme levels. Among 67,441 participants, data from 8,705 participants who underwent a fatty liver status and CAC assessment during routine health screening were analysed. CAC scores were calculated using computed tomography. NAFLD was diagnosed in patients with evidence of liver steatosis on ultrasonography. Obesity was defined as a body mass index of ≥25 kg/m2. Multivariate analysis showed a significant association between NAFLD and CAC in non-obese participants (odds ratio, 1.24 [95% confidence interval, 1.01-1.53]), whereas NAFLD and CAC were not associated in obese participants. Interaction analysis showed that the association between NAFLD and CAC was influenced by sex and obesity. Subgroup analysis revealed a significant association between NAFLD and CAC in non-obese male participants (odds ratio, 1.36 [1.07-1.75]), but not in female participants. Our study indicates that non-obese men with NAFLD are prone to CAC.

The association between the apolipoprotein B/A-I ratio and coronary calcification may differ depending on kidney function in a healthy population.

BACKGROUND: The apolipoprotein B/A-1 ratio has been reported to be one of the strongest risk predictors of cardiovascular events. However, its prognostic value for cardiovascular disease is still uncertain, especially in patients with chronic kidney disease. This study aimed to investigate whether the association between the apolipoprotein B/A-I ratio and coronary artery calcification differed according to kidney function in a healthy population. METHODS: Of the data from 7,780 participants from the medical records database in Gangnam Severance Hospital from 2005 through 2016, a cross-sectional analysis included participants with an estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m2 determined based on the Chronic Kidney Disease -Epidemiology Collaboration equation (n  =  1,800). Mild renal insufficiency was defined as an eGFR of 60-90 mL/min/1.73 m2. Coronary artery calcification measured with computed tomography was defined as an above-zero score. Logistic regression analyses were used to determine the association between coronary calcification and the apolipoprotein B/A-I ratio according to eGFR by adjusting for the influence of confounders. RESULTS: The mean apolipoprotein B/A-I level was significantly higher in the participants with coronary artery calcification than in the participants without coronary artery calcification. The apolipoprotein B/A-I ratio was significantly different according to coronary artery calcification in the participants with normal kidney function, but in the participants with mild renal insufficiency, it was not different. After adjusting for age, male sex, systolic blood pressure, body mass index, current smoking status, and fasting plasma glucose, the apolipoprotein B/A-I ratio was significantly associated with an increased risk of coronary artery calcification in participants with normal kidney function (odds ratio = 2.411, p = 0.011), while in the participants with mild renal insufficiency, the apolipoprotein B/A-I ratio was not associated with coronary artery calcification. CONCLUSION: Our study showed that the predictive value of apolipoprotein B/A-I ratio for coronary artery calcification may differ according to kidney function.