Toshihiko Yamaka

Significance of Serum Magnesium as an Independent Correlative Factor on the Parathyroid Hormone Level in Uremic Patients

CONTEXT PTH is a critical factor in mineral homeostasis, and chronic kidney disease mineral and bone metabolism disorder is a very important problem in patients with renal failure. Abnormal levels of PTH, serum phosphate, and calcium influence chronic kidney disease mineral and bone metabolism disorder, but there is little information about the influence of magnesium (Mg) on PTH. OBJECTIVE The aim of this study was to elucidate the correlation between magnesium and PTH levels in uremic patients just prior to beginning hemodialysis (HD) for the first time. PATIENTS We enrolled 1231 patients in nine Japanese facilities who had begun HD for end-stage renal disease. We investigated their serum Mg levels and the correlation between intact PTH (iPTH) and the serum Mg levels and other clinical parameters and medications. RESULTS The mean serum Mg was 2.2 ± 0.5 mg/dL, and hypermagnesemia was found in 663 patients (53.9%). Divided into two groups according to median iPTH level, the serum Mg levels were significantly higher in patients with low iPTH (2.3 ± 0.5 vs 2.1 ± 0.5, P < .01). Furthermore, divided into two groups according to the Mg level, iPTH levels were lower in patients with high Mg than in patients with normal serum Mg levels (277.9 ± 195.9 pg/mL vs 321.9 ± 203.7 pg/mL, P < .01). In the multiple regression analysis according to the effect of iPTH level, the serum Mg level was an independent variable after adjustment for other factors. CONCLUSIONS A high serum level of Mg is frequent in uremic patients with end-stage renal disease just prior to beginning HD. In the present set of patients, there was a significant correlation between the serum Mg and iPTH levels. Furthermore, the serum Mg level was an independent factor apart from the other factors regulating iPTH. These results suggest that serum Mg may be one of the factors regulating the serum PTH level in uremic patients.

Association between the Hemoglobin Level and Cardiothoracic Ratio in Patients on Incident Dialysis

Background/Aim: The present study explores associations between hemoglobin (Hb) levels and patients with cardiac enlargement in end-stage kidney disease (ESKD) to help prevent cardiac remodeling during the predialysis phase of chronic kidney disease (CKD). Methods: This cross-sectional study included 2,249 patients with ESKD (age, 67 w 13 years; male, 67%; diabetic kidney disease, 41%) who started hemodialysis (HD) between January 2006 and October 2013 at eight participating hospitals. We examined associations between Hb levels immediately before the first HD session and cardiothoracic ratios (CTRs). Clinical factors associated with the CTR were also assessed. Results: The mean Hb level was 8.7 w 1.6 g/dl, and the mean and median CTRs were 55.0 and 54.7%, respectively. The correlation between the Hb level and the CTR was linear and negative (r = -0.129, p < 0.001). The mean CTR and the prevalence of patients with a CTR >50% obviously decreased with increasing Hb levels (both p < 0.001 for trend). Univariate logistic regression analysis revealed an approximately 20% reduction in the odds ratio for complicating CTRs >50% per 1 g/dl increase in Hb. Hb levels of <9 g/dl were significantly associated with CTRs >50%. Numerical and categorical Hb remained significantly associated with CTRs >50% after adjusting for confounding variables. Conclusions: Lower Hb levels participate in progressive CTR enlargement in patients with ESKD, and maintaining Hb levels of >9 g/dl might help prevent cardiac remodeling during the predialysis phase of CKD. i 2014 S. Karger AG, Basel

Effect of erythropoietin-stimulating agent on uremic inflammation

BackgroundThe goal of the present study was to explore the effect of medications that are commonly prescribed for CKD patients on uremic state.MethodsThis was a cross-sectional study. From January 2006 to October 2009, 1,623 patients with end-stage kidney disease (ESKD) commenced hemodialysis (HD) at the 9 participating hospitals. The criteria for exclusion from the database were 1) serum C-reactive protein (CRP) > 3 mg/dL, 2) WBC count > 9,000/mm3 or <4,000/mm3, and 3) patients with cancer, immune complex disease, or vasculitis. A total of 900 patients were entered into the final database. We explored the association of serum CRP just before the first HD session with clinical characteristics, laboratory data, and medications for CKD in the predialysis period.ResultsOn univariate analysis, age, CTR, eGFR, and WBC were significantly correlated with CRP. Systolic and diastolic blood pressure, serum albumin, LDL-C, HDL-C, Hb, Cr, and Ca were inversely associated with CRP. Use of erythropoietin-stimulating agents (ESA) using (r = −0.111, p = 0.0015), renin-angiotensin-aldosterone system inhibitors (r = −0.083, p = 0.0154), and calcium channel blockers (r = −0.1, p = 0.0039) was also negatively correlated with CRP. However, only use of ESA showed a significant negative correlation with CRP that was independent of other clinical factors and CKD medications on multiple regression analysis.ConclusionESA may strongly reduce uremic inflammation in addition to improving anemia. To confirm this potential effect, a large-scale longitudinal study would be required.

Nephrologist care for 12 months or more increases hemodialysis initiation with permanent vascular access.

BackgroundThe objective of this study was to evaluate the effect of early referral (ER) to nephrologists on the type of vascular access (VA) available for use at the time of initiation of maintenance hemodialysis (HD). In patients who have been followed by nephrologists for less than 3 months, management before the initiation of HD is often insufficient and urgent initiation of HD is often necessary; therefore, patients in this study were limited to those who had been followed for at least 3 months by nephrologists.MethodsNine hundred and forty patients at 9 institutions affiliated to our study group were enrolled in this retrospective observational study.We defined patients followed up by nephrologists for at least 12 months as the early referral (ER) group and those followed for between 3 and 12 months as the late referral (LR) group. The type of VA available for use at the initiation of maintenance HD was compared between the groups.ResultsEarly referral was found to be significantly associated with the availability of a permanent VA, which included an arteriovenous fistula or arteriovenous graft, at the time of initiation of HD (odds ratio [OR] 1.705; P = 0.001). Multivariate analysis also revealed ER to be significantly associated with the availability of a permanent VA (OR 1.509; P = 0.023).ConclusionEarly referral was shown to be advantageous for increasing the likelihood of availability of a permanent VA, even after patients who had been followed up for less than 3 months by nephrologists were excluded.

Possible prevention of dialysis-requiring congestive heart failure by angiotensin-II receptor blockers in non-dialysis Japanese patients with Stage 5 chronic kidney disease

Background: Preventive medications for dialysis-requiring congestive heart failure (CHF) in non-dialysis Japanese patients with Stage 5 chronic kidney disease (CKD) are unknown. Our aim was to explore which CKD medication was associated with a reduced prevalence of dialysis-requiring CHF in non-dialysis Japanese patients with Stage 5 CKD. Methods: The present multicenter, retrospective, cross-sectional study examined the association between CKD medications and the prevalence of dialysis-requiring CHF in non-dialysis Japanese patients with Stage 5 CKD. Results: There were 1536 Japanese Stage 5 CKD patients who satisfied our inclusion criteria. We had 309 (20.1%) patients whom had developed dialysis-requiring CHF and 940 patients (60.8%) whom had been using angiotensin-II receptor blockers (ARBs) before initiating dialysis. In our multivariate analysis, only ARB use was significantly associated with a lower risk of CHF (Odds ratio (OR): 0.680, 95% confidence interval (CI): 0.516–0.897; p = 0.0064), of the CKD treatments examined in this study. Conclusions: We found that ARB use during the pre-dialysis period is associated with a lower prevalence of CHF in the non-dialysis Japanese patients with Stage 5 CKD, suggesting a possible prevention of dialysis-requiring CHF by ARBs, in non-dialysis Japanese patients with Stage 5 CKD.

Properties of physical activity and optimum hemoglobin concentration in chronic hemodialysis patients

社会復帰に必要なヘモグロビン (Hb) 濃度や最大運動能力について検討するため, 27例の女性慢性血液透析 (HD) 患者と10例の女性健常者にHb濃度, 日常の歩行数の測定および運動負荷試験を施行し, 下記の成績を得た.HD患者の平均歩行数は, 健常群と比較し26.2%低値であった. 運動群に対し非運動群の歩行数は, 有意に低値であった. 職業群に対し主婦群の歩行数は, 有意に低値であった. HD患者の歩行数と年齢とに有意な負の相関関係が認められた. しかし健常者においては, 歩行数と年齢とに有意な相関関係が認められず, 年齢に関わらず歩行数は一定であった.HD患者における歩行数はHb濃度が上昇するに従い直線的に増加したが, 8.2g/dl以上まで上昇すると健常者と同水準になり, 増加傾向を示さず一定となった. HD患者における歩行数と最大酸素摂取量は, 有意な相関関係が認められた.以上のことから, HD患者の社会復帰に必要なHb濃度は日常の身体活動量を指標にすると, およそ8.2g/dl程度と考えられた. また日常の身体活動量に応じ, 必要となる最大運動能力の推測が可能と考えられた.

Studies of factors limiting maximal aerobic work capacity in patients on chronic hemodialysis

慢性血液透析 (HD) 患者の最大有酸素運動能力の制限因子を検討する目的で, 35例のHD患者と52例の健常者に対して, 心機能および末梢循環機能を評価し, またヘモグロビン濃度を測定した. HD患者は心疾患の合併がなく, β-遮断剤やdigitalis製剤の服用もしていない症例であった. また運動負荷試験の中止理由が心電図異常や血圧異常でない症例であることを厳守した. 全対象において最大運動負荷試験より得られた最大酸素摂取量, 最大pressure rate productからBruceの計算式に従いfunctional aerobic impairment (FAI), left ventricular impairment (LVI) およびperipheral circulatory impairment (PCI) を求めた. HD患者のヘモグロビン濃度は最大運動負荷試験の前に測定した.その結果, 次のような成績が得られた. HD患者のFAI, LVIおよびPCIは, 健常者と比較して有意に高い値を示した. またHD患者のPCIはLVIよりも高値を示した. 健常者のFAIはLVIとPCIの両方に有意な相関関係を認めた. しかしHD患者のFAIはLVIとは相関せず, PCIのみに有意な相関関係を認めた. HD患者のFAIはヘモグロビン濃度との間に有意な相関関係を認めなかった.以上の成績からHD患者の最大有酸素運動能力の制限を決定する因子としては, 心機能の低下よりもヘモグロビン濃度の低下以外の末梢循環系の機能の低下に関係するものと考えられた.