Oral Iron Absorption of Ferric Citrate Hydrate and Hepcidin-25 in Hemodialysis Patients: A Prospective, Multicenter, Observational Riona-Oral Iron Absorption Trial.

Oral ferric citrate hydrate (FCH) is effective for iron deficiencies in hemodialysis patients; however, how iron balance in the body affects iron absorption in the intestinal tract remains unclear. This prospective observational study (Riona-Oral Iron Absorption Trial, R-OIAT, UMIN 000031406) was conducted at 42 hemodialysis centers in Japan, wherein 268 hemodialysis patients without inflammation were enrolled and treated with a fixed amount of FCH for 6 months. We assessed the predictive value of hepcidin-25 for iron absorption and iron shift between ferritin (FTN) and red blood cells (RBCs) following FCH therapy. Serum iron changes at 2 h (ΔFe2h) after FCH ingestion were evaluated as iron absorption. The primary outcome was the quantitative delineation of iron variables with respect to ΔFe2h, and the secondary outcome was the description of the predictors of the body's iron balance. Generalized estimating equations (GEEs) were used to identify the determinants of iron absorption during each phase of FCH treatment. ΔFe2h increased when hepcidin-25 and TSAT decreased (-0.459, -0.643 to -0.276, p = 0.000; -0.648, -1.099 to -0.197, p = 0.005, respectively) in GEEs. FTN increased when RBCs decreased (-1.392, -1.749 to -1.035, p = 0.000) and hepcidin-25 increased (0.297, 0.239 to 0.355, p = 0.000). Limiting erythropoiesis to maintain hemoglobin levels induces RBC reduction in hemodialysis patients, resulting in increased hepcidin-25 and FTN levels. Hepcidin-25 production may prompt an iron shift from RBC iron to FTN iron, inhibiting iron absorption even with continued FCH intake.

Vascular mapping for the decision of hemodialysis access method: Case report.

Preoperative ultrasound vascular mapping was performed to determine the surgical method for two cases where standard arteriovenous fistula was not possible. In case 1, the previous arteriovenous fistula of the left arm was occluded, and arteriovenous graft of the right arm was thrombosed after frequent percutaneous transluminal angioplasty. Contrast medium was contraindicated because of allergy. Using preoperative ultrasound vascular mapping, we were able to establish the appropriate surgical method. In case 2, hemodialysis was started by catheter insertion, and then access creation was planned. This case was treated with steroids due to a bullous pemphigoid disease and there was a high risk of infection, which precluded the use of synthetic grafts. There was also the possibility of delay in healing due to malnutrition. Therefore, appropriate surgical method was tailored by using preoperative ultrasound vascular mapping. Ultrasound vascular mapping was useful for determining the surgical creation of an appropriate access for facilitating hemodialysis cannulation.

Cut-off value of the ankle-brachial pressure index at which the accuracy of brachial-ankle pulse wave velocity measurement is diminished.

BACKGROUND: The present study was conducted to establish the cutoff value of the ankle-brachial pressure index (ABI) at which the accuracy of brachial-ankle pulse wave velocity (baPWV) measurement is diminished. METHODS AND RESULTS: The baPWV and ABI were measured in 1,361 patients with an atherosclerosis-related disease and 7,889 subjects without any atherosclerotic risk factors, in order to determine the percent difference of the brachial-ankle PWV (%baPWV), the angle of the rise of the anacrotic limb (%angle) and of the amplitude of the entire waveform (%amplitude) in both sides. The %angle and %amplitude were significantly higher in subjects whose %baPWV was >or=19% than in those subjects whose %baPWV was <19% (19% was the mean value+3SD of 7,889 healthy subjects). The %baPWV >or=19% was defined as the abnormal discrepancy of baPWV caused by arterial stenosis in both sides. The receiver operator characteristic curve discriminated the abnormal discrepancy of baPWV by ABI because the area under the curve was 0.86. The highest discriminating sensitivity and specificity were 91% and 75% at ABI =0.95. CONCLUSION: An ABI <0.95 seems to be the marker of diminished baPWV accuracy.

Comparison of ankle-brachial pressure index and pulse wave velocity as markers of the presence of coronary artery disease in subjects with a high risk of atherosclerotic cardiovascular disease.

Recently, a measurement device that can simultaneously measure the ankle-brachial pressure index (ABI) and brachial-ankle pulse wave velocity (PWV) has become available. The present study compares the applicability of ABI and PWV as markers for predicting the prevalence of coronary artery disease (CAD) in subjects with a high risk of atherosclerotic cardiovascular disease. The ABI and brachial-ankle PWV were measured in 472 consecutive subjects who subsequently underwent coronary angiography for diagnosis or exclusion of CAD. The prevalence of CAD in the lowest ABI quartile was higher than those in the other 3 ABI quartiles, whereas the prevalence in the lowest brachial-ankle PWV quartile was lower than those in the other 3 brachial-ankle PWV quartiles. A multivariate logistic regression analysis demonstrated that the lowest ABI quartile was a significant independent variable for the prevalence of CAD and that the lowest brachial-ankle PWV quartile was a significant independent variable for the absence of CAD in a population. Thus, a low ABI is an independent marker for an additive risk of CAD, whereas a low brachial-ankle PWV may be used as an independent marker for excluding the risk of CAD among subjects with a high risk of atherosclerotic cardiovascular disease.