中井 滋

The prevalence and incidence of end-stage kidney disease (ESKD) have continued to increase worldwide. Japan was known as having the highest prevalence of ESKD in the world; however, Taiwan took this place in 2001, with the USA still in third position. However, the prevalence data from Japan and Taiwan consisted of dialysis patients only. The prevalence and incidence of Kidney Transplantation (KT) in Japan were quite low, and the number of KT patients among those with ESKD was regarded as negligibly small. However, the number of KT recipients has increased recently. Furthermore, there are no reports about nationwide surveys on the prevalence and incidence of predialysis chronic kidney failure patients in Japan. This review describes our recent study on the estimated number of chronic kidney disease (CKD) stage G5 patients and the number of ESKD patients living in Japan, obtained via the cooperation of five related medical societies. From the results, as of Dec 31, 2007, 275,242 patients had received dialysis therapy and 10,013 patients had a functional transplanted kidney, and as of Dec 31, 2008, 286,406 patients had received dialysis therapy and 11,157 patients had a functional transplanted kidney. Consequently, there were 285,255 patients with CKD who reached ESKD and were living in Japan in 2008 and 297,563 in 2009. We also estimated that there were 67,000 predialysis CKD stage G5 patients in 2009, 37,365 patients introduced to dialysis therapy, and 101 patients who received pre-emptive renal transplantation in this year. In total, there were 37,466 patients who newly required renal replacement therapy (RRT) in 2009. Not only the average ages, but also the primary renal diseases of the new ESKD patients in each RRT modality were different.

2009年より日本透析医学会統計調査委員会の年末全国調査の一環として日本腹膜透析医学会の協力のもと「腹膜透析（PD）レジストリ」が開始されている．今回2012年末に行われた調査結果からPD患者の現状を報告する．対象は2012年末全国調査で報告されたわが国のPD患者．血液（濾過）透析（HD（F））等との併用状況，透析液交換方法，自動腹膜透析装置（APD）使用状況，腹膜炎および出口部感染発症率などについて記述的解析を行った．2012年末の施設調査では，PD患者数は9,514人で2011年末と比較し128人減少し，全透析患者に占める割合も3.1％と0.1％減少した．腹膜カテーテルを残している洗浄患者347人，新規PD導入するも年内脱落した患者175人，HD（F）等とPDを併用している患者1,932人であった．HD（F）等併用療法の割合は1年未満で4.8％なのに対し，1～2年未満で9.2％，2～4年未満で16.3％，4～8年未満で32.0％，8年以上で47.5％とPD歴が長くなるにつれて高くなっていた．透析液交換方法に関しては完全手動交換のみを行うPD患者は29.8％，紫外線もしくは熱式無菌接合装置によるバッグ交換デバイスを用いているPD患者はそれぞれ54.7％，13.9％であった．APDの使用割合はPD歴1年未満で43.4％であったのに対し，PD歴2年以上ではPD歴が長くなるほどAPD使用割合は減少していた．腹膜炎発症率は平均0.22回/1患者・年であった．出口部感染発症率は平均0.36回/1患者・年であった．

2012年末の統計調査は全国の4,279施設を対象に実施され, 4,238施設 (99.0％) から回答を得た. 2012年1年間の年間導入患者数は38,055人であった. 年間導入患者数は2008年以降大きな増減なく推移している. 2012年1年間に死亡した患者は30,710人であり, 2011年の死亡数30,743人よりも僅かに減少し, 透析人口は依然増加し続け, 2012年末の透析人口は310,007人と31万人を超えた. 人口百万人あたりの患者数は2,431.2人である. 2011年末から2012年末までの年間粗死亡率は10.0％であり, 2011年の粗死亡率10.2％からわずかに減少した. 透析導入症例の平均年齢は68.5歳, 透析人口全体の平均年齢は66.9歳であった. 年間導入患者腎不全原疾患では糖尿病性腎症が最も多かった (44.2％). 糖尿病性腎症による年間導入実数は, ここ数年16,000人前後で横ばいである. 透析人口全体で最も多い腎不全原疾患は糖尿病性腎症であり (37.1％), 次いで慢性糸球体腎炎が多かった (33.6％). 糖尿病性腎症は増加し続けているが, 慢性糸球体腎炎は実数も減っている. 2012年末に血液透析濾過 (HDF) を施行されていた患者は21,725人であり, 2011年末の14,115人から大幅に増加した. 特にon-line HDFは2011年末4,890人から2012年末14,069人へと約3倍に増加した. 施設調査結果によれば腹膜透析 (PD) 患者数は9,514人, PDは行っていないがPDカテーテルを腹腔に留置している患者は347人であった. 患者調査によれば1,932人がPDとともに血液透析 (HD) やHDFなど体外循環を使用した透析療法を併用していた. 2012年末の在宅HD患者は393人であり, 2011年末の327人から大きく増加した.

Background/Aims: This study aims to identify current risk factors for developing dialysis-related amyloidosis using carpal tunnel syndrome (CTS) as proxy for general amyloidosis. Methods: The cohort consisted of 166,237 patients on dialysis (mean age 66.1 +/- 12.4 years; mean dialysis vintage 7.2 +/- 6.4 years) who could be followed for a year between 2010 and 2011. Of these, 2,157(1.30%) needed first-time CTS surgery during the study period. Odds ratios (ORs) for CTS were calculated at a 95% confidence interval (95% Cl) after adjusting for age, gender, primary kidney disease, history of smoking, history of hypertension vintage, dialysis modality, use of high-flux membrane, body mass index, serum albumin, Kt/V, normalized protein catabolic rate, C-reactive protein, pretreatment beta(2)-microglobulin (beta(2)MG), and beta(2)MG clearance. Results: Adjusted ORs of first-time CTS for vintages 10-15, 15-20, 20-25 (referent), 25-30, and >30 years were, respectively, 0.18 (0.12-0.26), 0.43 (0.31-0.62), 1.00, 2.37 (1.64-3.40), and 3.87(2.52-5.93). Adjusted ORs for ages 40-50, 50-60 (referent), 60-70, 70-80, and >80 were 0.53 (0.30-0.94), 1.00, 1.89 (1.41-2.52), 1.52 (1.08-2.14), and 1.04 (0.60-1.80). Female gender, low serum albumin, and diabetic nephropathy were also associated with CTS. Pretreatment serum beta(2)MG and beta(2)MG clearance <80% were not significant, although beta(2)MG clearance >80% was negatively associated with CTS [OR 0.34 (0.13-0.90)]. Conclusion: ORs of first-time CTS almost doubled with every 5-year increase in dialysis vintage. ORs of CTS were highest for patients aged 60-70. Other factors associated with CTS were gender, serum albumin, and diabetic nephropathy beta(2)MG clearance >80% may decrease the incidence of CTS. (C) 2014 S. Karger AG, Basel

A nationwide statistical survey of 4255 dialysis facilities was conducted at the end of 2011. Responses were submitted by 4213 facilities (99.0%). The number of new patients started on dialysis was 38613 in 2011. Although the number of new patients decreased in 2009 and 2010, it increased in 2011. The number of patients who died each year has been increasing; it was 30743 in 2011, which exceeded 30000 for the first time. The number of patients undergoing dialysis has also been increasing every year; it was 304856 at the end of 2011, which exceeded 300000 for the first time. The number of dialysis patients per million at the end of 2011 was 2385.4. The crude death rate of dialysis patients in 2011 was 10.2%, which exceeded 10% for the first time in the last 20 years. The mean age of new dialysis patients was 67.84 years and the mean age of the entire dialysis patient population was 66.55 years. The most common primary cause of renal failure among new dialysis patients was diabetic nephropathy (44.3%). Diabetic nephropathy was also the most common primary disease among the entire dialysis patient population (36.7%), exceeding chronic glomerulonephritis (34.8%) which had been the highest until last year. The survey included questions related to the Great East Japan Earthquake, which occurred on 11 March 2011. The results on items associated with the Great East Japan Earthquake were reported separately from this report. The mean uric acid levels of the male and female patients were 7.30 and 7.19mg/dL, respectively. Certain drugs for hyperuricemia were prescribed for approximately 17% of patients. From the results of the facility survey, the number of patients who underwent peritoneal dialysis (PD) was 9642 and the number of patients who did not undergo PD despite having a peritoneal dialysis catheter was 369. A basic summary of the results on the survey items associated with PD is included in this report and the details were reported separately.

Amyloid beta proteins (Aβ) in the brain are the main cause of Alzheimer's disease. Peripheral administration of Aβ-binding substances, which may act as a sink for Aβ from the brain, has been reported to reduce brain Aβ. We previously found C16-cellulose beads had high Aβ-removal activity in vitro. In this study, we investigated the optimum surface properties of adsorbents for removal of Aβ in vitro and in humans. Batch analysis was performed with porous cellulose beads or silica beads with or without 2-22 methylene groups. Aβ-removal activity of C16-cellulose beads increased with increasing alkyl chain length. In contrast, with cellulose the amount of Aβ removed by the silica beads decreased with increasing alkyl chain length. Cellulose beads with 16 or 22 methylene groups were best (over 99 % removal) among all the beads tested (p ≤ 0.01). The adsorbent surfaces were analyzed by near-infrared spectroscopy, which revealed that the optimum beads had a sufficiently hydrophobic surface with an appropriate amount of adsorbed water accessible on the surface. Aβ removal efficiency by C16-cellulose beads was investigated for 5 renal failure patients on hemodialysis, resulting in 51.1 ± 6.6 % for Aβ1-40 and 43.8 ± 4.5 % for Aβ1-42 (p ≤ 0.01). In conclusion, cellulose beads with 16 or 22 methylene groups and an appropriate amount of adsorbed water were the optimum Aβ adsorbents. The device with C16-cellulose beads had high Aβ removal activity in humans. These adsorbents might be useful for Alzheimer's disease therapy. © 2012 The Japanese Society for Artificial Organs.

To clarify the therapeutic impact of tonsillectomy and combined therapies of tonsillectomy plus steroid on the long-term prognosis of immunoglobulin A nephropathy (IgAN). A retrospective study was conducted on 208 patients with IgAN between 1986 and 2009. According to the strategies for treatments, patients were divided into four groups: tonsillectomy and steroid pulse (TSP, n = 47), tonsillectomy and oral steroid (TOS, n = 33), tonsillectomy alone (T, n = 56), and N group (no particular therapy, n = 72). Multivariate analysis based on the Cox's regression model was used to assess the relative risk of reaching the outcome of doubling creatinine based on the influence of baseline prognostic factors. The mean observation periods were 53.8 months in the TSP group, 122.0 months in the TOS group, 102.9 months in the T group, and 84.6 months in the N group. During an observation period, serum creatinine levels doubled as follows: one in the TSP group (2.1 %), two in the TOS group (6.1 %), five in the T group (8.9 %), histological severity, and 22 in the N group (30.6 %). The Cox's regression proportional hazard model showed that gender, age, histological activity, dialysis induction risk and therapy were associated with doubling creatinine levels. Hazard ratios (95 % CI) and (P value) in T, TOS, and TSP groups versus N were 0.314 (0.11-0.93, P = 0.037), 0.213 (0.04-1.10, P = 0.065), and 0.032 (0.00-0.28, P = 0.002), respectively. A combination therapy of tonsillectomy and steroid pulse had the most significant therapeutic impact compared to other therapies.

2011年末の統計調査は全国の4,255施設を対象に実施され，4,213施設（99.0％）から回答を回収した．2011年1年間の年間導入患者数は38,613人であった．年間導入患者数は2009年，2010年と減少していたが，2011年は増加に転じた．年間死亡患者数は増加し続けており，2011年1年間に死亡した患者は30,743人と初めて年間3万人を超えた．わが国の透析人口は増加し続けているが，2011年末の透析人口は304,856人とこちらも初めて30万人を超えた．人口百万人あたりの患者数は2,385.4人である．2010年末から2011年末までの年間粗死亡率は10.2％であり，この20年間で初めて10％を超えた．透析導入症例の平均年齢は67.84歳，透析人口全体の平均年齢は66.55歳であった．年間導入患者腎不全原疾患では糖尿病性腎症が最も多かった（44.3％）．透析人口全体での腎不全原疾患は昨年調査まで最多であった慢性糸球体腎炎（34.8％）を抜いて，糖尿病性腎症（36.7％）が最も多く認められる原疾患となった．2011年3月11日に発生した東日本大震災に関連した調査では，震度6以上を経験した施設は東北地方に，震度5以上6未満を経験した施設は関東地方に多かった．震災を原因として操業不能となった施設は315施設存在し，これに伴って合計10,906人の透析患者が施設間を移動していた．週3回の施設血液透析を施行されている男性透析患者の尿酸値の平均は7.30 mg/dL，女性の平均は7.19 mg/dLであった．約17％の患者に何らかの高尿酸血症治療薬が使用されていた．施設調査結果によれば腹膜透析（PD）患者数は9,642人，PDは行っていないがPDカテーテルを腹腔に留置している患者は369人であった．

The pathological changes of Alzheimer's disease include the deposition of amyloid beta protein (A beta) as senile plaques in the brain. We hypothesized that the rapid removal of A beta s from the blood may act as a peripheral A beta drainage sink from the brain. In this study, the plasma A beta concentrations and the cognitive functions were investigated for in 57 patients on hemodailysis (69.4 +/- A 3.8 years), 26 renal-failure patients without hemodialysis (66.6 +/- 14.7 years), and 17 age-matched healthy controls (66.6 +/- 4.1 years). The concentrations of plasma A beta s increased along with the decline of renal functions. Moreover, the renal-failure patients without hemodialysis and with poorer renal functions showed lower cognitive functions. The plasma concentrations of A beta(1-42) correlated with serum creatinine (P < 0.001) and Mini-Mental-State Examination scores (P = 0.017). The dialyzers effectively removed A beta s in the blood during hemodialysis sessions. The plasma A beta concentrations showed steady or slightly decreasing along with duration of hemodialysis. The total amount of A beta s removed during a hemodialysis session was calculated to be comparable to the A beta s dissolved in the blood and the cerebrospinal fluid. The MMSE scores of the hemodialysis patients showed no clear decrease in longer hemodialysis duration. Therefore, the therapeutic approach for Alzheimer's disease by removing A beta s from the blood is worthy of further investigation, including whether or not A beta s in the brain decrease.

A nationwide statistical survey of 4226 dialysis facilities was conducted at the end of 2010, and 4166 facilities (98.6%) responded. The number of new patients introduced into dialysis was 37 512 in 2010. This number has decreased for two consecutive years since it peaked in 2008. The number of patients who died in 2010 was 28 882, which has been increasing every year. The number of patients undergoing dialysis at the end of 2010 was 298 252, which is an increase of 7591 (2.6%) compared with that at the end of 2009. The number of dialysis patients per million at the end of 2010 was 2329.1. The crude death rate of dialysis patients in 2010 was 9.8%, and has been gradually increasing. The mean age of the new patients introduced into dialysis was 67.8 years and the mean age of the entire dialysis patient population was 66.2 years. Regarding the primary disease of the new patients introduced into dialysis, the percentage of patients with diabetic nephropathy was 43.6%, which is a slight decrease from that in the previous year (44.5%). Patients with diabetic nephropathy as the primary disease accounted for 35.9% of the entire dialysis patient population, which approaches the percentage of patients with chronic glomerulonephritis as the primary disease (36.2%). The percentage of patients who had undergone carpal tunnel release surgery (CTx) was 4.3%, which is a slight decrease from that at the end of 1999 (5.5%). The decrease in the percentage of patients who had undergone CTx was significant among the patients with dialysis durations of 2024 years (1999, 48.0%; 2010, 23.2%). A total weekly Kt/V attributable to peritoneal dialysis and their residual functional kidney was 1.7 or higher for 59.4% of patients who underwent peritoneal dialysis.

日本透析医学会が2001年から2010年までを対象期間として，全国の透析施設を対象に実施した調査の報告に基づいてわが国の透析人口の将来推計を試みた．各年の施設調査回収率によって補正された2001年末から2010年末までの各年末透析人口に基づいて2002年から2010年までの9か年の各年について透析人口年間増加率を算出した．次いで西暦年をx，当該年の透析人口年間増加率をyとする直線回帰を最小二乗法にて行い，その回帰式を求めた（y＝450.372044－0.222751 x，R-square＝0.7227，p＝0.0037）．この回帰式に基づいて2011年以降の各年透析人口年間増加率を推定し，推定された年間増加率に従って各年末透析人口を逐次推計した．その結果，わが国の透析人口は2021年末に348,873人（90％信頼区間：302,868～401,119人）で最大となり，その後減少に転じることが推計された．

Home hemodialysis (HHD) started in Japan in 1969. It has been done in the largest number of patients with the purpose of better social reintegration, followed by patients for whom commuting to a hospital is geographically difficult. In a subanalysis of the JSDT patient registry, the survival rate at 9 years for male patients excluding those with diabetes was significantly better in HHD patients than in facility dialysis patients. This result was thought to indicate that HHD was superior treatment both medically and socially, but it has not increased greatly because of conditions that impede the implementation of HHD, such as finding a caregiver and the burden on the caregiver, as well as the burden of light, heat, and water costs. However, long-duration dialysis and frequent dialysis are done even in general dialysis treatment, and the number of HHD patients has increased recently because of some improvement in health insurance payments for HHD in 1998. The spread of HHD is essential also in the broad implementation of diversifying HD modalities, and maintaining an accurate registry of HHD patients, analyzing factors that affect survival rates with each modality, clarifying conditions for adequacy of dialysis, and clarifying which treatments are superior are important future issues for dialysis treatment. Copyright © 2012 S. Karger AG, Basel.

透析時間，血流量および透析量（Kt urea）と生命予後の関係の，患者背景による違いを明らかにするため，日本透析医学会の統計調査結果を用いて，後ろ向きの観察的研究を行った．2002年末の週3回施設血液透析患者を対象に，事故・自殺を除く死亡をエンドポイントとして，2003年末までの1年死亡リスクと2007年末までの5年死亡リスクについて，ロジスティック回帰分析を行った．性，年齢，透析後体重（post dialysis body weight：PDBW），透析前アルブミン値（Alb），％クレアチニン産生速度（％CGR），標準化蛋白異化率（normalized protein catabolic rate：nPCR）で層別化して検討した．透析歴5年以上の患者の結果は以下の通りであった．透析時間は240分以上270分未満を基準とすると，患者背景によらず，透析時間が短い患者群で死亡リスクが高く，長い患者群で死亡リスクが低かった．血流量は200mL/分以上220mL/分未満を基準とすると，血流量が少ない患者群で死亡リスクが高かった．女性，年齢75歳以上，PDBW 40kg未満，Alb 3.0g/dL未満，％CGR 80％未満，nPCR 0.7g/kg/day未満の患者を除き，血流量が多い患者群で死亡リスクが低かった．Kt ureaは38.8L以上42.7L未満を基準とすると，Kt ureaが小さい患者群では死亡リスクが高かった．Alb 3.0g/dL未満，％CGR 80％未満，nPCR 0.7g/kg/day未満の患者を除き，Kt ureaが大きい患者群で死亡リスクが低かった．透析歴5年未満の患者でも，同様の結果であった．一般的な週3回血液透析では，栄養状態が不良な患者を除き，基本的に透析時間の延長や血流量の増加により透析量を増大させることで，患者の生命予後を改善する可能性が示唆された．

透析時間，血流量および透析量（Kt urea）と生命予後の関係の，患者背景による違いを明らかにするため，日本透析医学会の統計調査結果を用いて，後ろ向きの観察的研究を行った．2002年末の週3回施設血液透析患者を対象に，事故・自殺を除く死亡をエンドポイントとして，2003年末までの1年死亡リスクと2007年末までの5年死亡リスクについて，ロジスティック回帰分析を行った．性，年齢，透析後体重（post dialysis body weight：PDBW），透析前アルブミン値（Alb），％クレアチニン産生速度（％CGR），標準化蛋白異化率（normalized protein catabolic rate：nPCR）で層別化して検討した．透析歴5年以上の患者の結果は以下の通りであった．透析時間は240分以上270分未満を基準とすると，患者背景によらず，透析時間が短い患者群で死亡リスクが高く，長い患者群で死亡リスクが低かった．血流量は200mL/分以上220mL/分未満を基準とすると，血流量が少ない患者群で死亡リスクが高かった．女性，年齢75歳以上，PDBW 40kg未満，Alb 3.0g/dL未満，％CGR 80％未満，nPCR 0.7g/kg/day未満の患者を除き，血流量が多い患者群で死亡リスクが低かった．Kt ureaは38.8L以上42.7L未満を基準とすると，Kt ureaが小さい患者群では死亡リスクが高かった．Alb 3.0g/dL未満，％CGR 80％未満，nPCR 0.7g/kg/day未満の患者を除き，Kt ureaが大きい患者群で死亡リスクが低かった．透析歴5年未満の患者でも，同様の結果であった．一般的な週3回血液透析では，栄養状態が不良な患者を除き，基本的に透析時間の延長や血流量の増加により透析量を増大させることで，患者の生命予後を改善する可能性が示唆された．

Previous studies have suggested that early initiation of dialysis therapy was not superior in terms of patient survival. In this study, we analyzed the effects of renal function at the start of renal replacement therapy (RRT), duration of nephrology care, and comorbidity on 12-month survival of end-stage renal disease (ESRD) patients. The subjects in this study were 9695 new ESRD patients who started RRT in 2007. The average age of the subjects was 67.5 years, 64.1% of the subjects were male, and 42.9% had diabetes. During the 12-month period after the start of RRT, 1546 patients died, and 35 patients received renal transplantation. Average estimated glomerular filtration rate (eGFR) at the initiation of dialysis was 6.52 +/- 4.20 mL/min/1.73 m2. By unadjusted logistic analysis, one-year Odds Ratio (OR) of mortality in patients with eGFR more than 46 mL/min/1.73 m2 was increased with increased eGFR at dialysis initiation, but the OR was identical among the groups with eGFR less than 4 mL/min/1.73 m2. After adjustment for age, gender, underlying renal diseases, and other clinical characteristics at dialysis initiation, OR was identical among the groups with eGFR less than 8 mL/min/1.73 m2. Furthermore, an OR increment was observed in eGFR less than 4 mL/min/1.73 m2 group. In terms of the duration of nephrology care before dialysis initiation, 6 months or longer of nephrology care significantly decreased the OR of mortality after adjustment of covariance. Not only patients with sufficient residual renal function at the initiation of dialysis, but also patients with very low eGFR at the initiation of dialysis showed poor survival.

A nationwide statistical survey of 4196 dialysis facilities was conducted at the end of 2009, and 4133 facilities (98.5%) responded. The number of patients undergoing dialysis at the end of 2009 was determined to be 290 661, an increase of 7240 patients (2.6%) compared with that of 2008. The number of dialysis patients per million at the end of 2009 was 2279.5. The crude death rate of dialysis patients from the end of 2008 to the end of 2009 was 9.6%. The mean age of the new patients introduced into dialysis was 67.3 years old and the mean age of the entire dialysis patient population was 65.8 years old. Primary diseases such as diabetic nephropathy and chronic glomerulonephritis for new dialysis patients, showed a percentage of 44.5% and 21.9%, respectively. Based on the facilities surveyed, 84.2% of the facilities that responded to the questionnaire satisfied the microbiological quality standard for dialysis fluids for the Japanese Society for Dialysis Therapy (JSDT), with an endotoxin concentration of less than 0.05 EU/mL in the dialysis fluid. Similarly, 98.2% of the facilities surveyed satisfied another standard of the society of a bacterial count of less than 100 cfu/mL in the dialysis fluid. The facility survey indicated that the number of patients who were treated by blood purification by both peritoneal dialysis and extracorporeal circulation, such as hemodialysis, was 1720. Among the total number of patients, 24.8% were satisfied with the management target recommended in the treatment guidelines for secondary hyperparathyroidism. These standards are set by the JSDT, based on the three parameters, i.e. serum calcium concentration, serum phosphorus concentration, and serum intact parathyroid hormone concentration. According to the questionnaire, 9.8% of the patients were considered to have a complication of dementia.

2010年末の統計調査は全国の4,226施設を対象に実施され，4,166施設（98.6％）から回答を回収した．2010年1年間の年間導入患者数は37,512人であった．年間導入患者数は2008年をピークとして2年続けて減少した．2010年1年間に死亡した患者は28,882人であり，年間死亡患者数は増加し続けている．2010年末のわが国の透析人口は298,252人であり，昨年末に比べて7,591名（2.6％）の増加であった．人口百万人あたりの患者数は2,329.1人である．2009年末から2010年末までの年間粗死亡率は9.8％であり，緩やかに増加しつつある．透析導入症例の平均年齢は67.8歳，透析人口全体の平均年齢は66.2歳であった．年間導入患者に占める糖尿病性腎症を原疾患とする患者の割合は43.6％であり，昨年の44.5％に比べて減少した．透析人口に占める糖尿病性腎症を原疾患とする患者の割合は35.9％であり，慢性糸球体腎炎を原疾患とする患者の割合である36.2％に近づいた．手根管開放術（CTx）の既往を持つ患者は透析人口全体の4.3％に認められたが，これは1999年末の5.5％に比べて減少していた．CTxの既往を持つ患者の割合の減少は，透析歴が20～24年の患者において顕著であった（1999年48.0％，2010年23.2％）．腹膜透析による週Kt／Vと残存腎による週Kt／Vの和が1.7以上に達していたのは，腹膜透析患者全体の59.4％であった．

Background: Patient responsiveness to erythropoiesis-stimulating agents (ESAs), notoriously difficult to measure, has attracted attention for its association with mortality. We defined categories of ESA responsiveness and attempted to clarify their association with mortality. Study Design: Cohort study. Setting & Participants: Data from Japan's dialysis registry (2005-2006), including 95,460 adult hemodialysis patients who received ESAs. Predictor: We defined 6 categories of ESA responsiveness based on a combination of ESA dosage (low [<6,000 U/wk] or high [>= 6,000 U/wk]) and hemoglobin level (low [<10 g/dL], medium [10-11.9 g/dL], or high [>= 12 g/dL]), with medium hemoglobin level and low-dose ESA therapy as the reference category. Outcomes: All-cause and cardiovascular mortality during 1-year follow-up. Measurements: HRs were estimated using a Cox model for the association between responsiveness categories and mortality, adjusting for potential confounders such as age, sex, postdialysis weight, dialysis duration, comorbid conditions, serum albumin level, and transferrin saturation. Results: Median ESA dosage (4,500-5,999 U/wk) was used as a cutoff point, and mean hemoglobin level was 10.1 g/dL in our cohort. Of 95,460 patients during follow-up, 7,205 (7.5%) died of all causes, including 5,586 (5.9%) cardiovascular deaths. Low hemoglobin levels and high-dose ESA therapy were both associated with all-cause mortality (adjusted HRs, 1.18 [95% CI, 1.09-1.27] for low hemoglobin level with low-dose ESA and 1.44 [95% CI, 1.34-1.55] for medium hemoglobin level with high-dose ESA). Adjusted HRs for high-dose ESA with low hemoglobin level (hyporesponsiveness) were 1.94 (95% CI, 1.82-2.07) for all-cause and 2.02 (95% CI, 1.88-2.17) for cardiovascular mortality. We also noted the interaction between ESA dosage and hemoglobin level on all-cause mortality (likelihood ratio test, P = 0.002). Limitations: Potential residual confounding from unmeasured factors and single measurement of predictors. Conclusions: Mortality can be affected by ESA responsiveness, which may include independent and interactive effects of ESA dose and hemoglobin level. Responsiveness category has prognostic importance and clinical relevance in anemia management. Am J Kidney Dis. 59(1):108-116. (C) 2011 by the National Kidney Foundation, Inc.

2009年末の統計調査は全国の4,196施設を対象に実施され，4,133施設（98.5％）から回答を回収した．2009年末のわが国の透析人口は290,661人であり，昨年末に比べて7,240名（2.6％）の増加であった．人口百万人あたりの患者数は2,279.5人である．2008年末から2009年末までの1年間の粗死亡率は9.6％であった．透析導入症例の平均年齢は67.3歳，透析人口全体の平均年齢は65.8歳であった．透析導入症例の原疾患ごとのパーセンテージでは，糖尿病性腎症が44.5％，慢性糸球体腎炎は21.9％であった．施設調査の結果，日本透析医学会の透析液水質管理基準である透析液エンドトキシン濃度0.05EU/mL未満は，回答施設の84.2％において達成されていた．回答施設の98.2％において，日本透析医学会の透析液水質管理基準による細菌数推奨値100cfu/mL未満は達成されていた．患者調査において腹膜透析とともに血液透析など体外循環を利用した血液浄化法を併用しているとされた患者は1,720人であった．日本透析医学会の二次性副甲状腺機能亢進症治療ガイドラインが推奨する管理目標を，血清カルシウム濃度，血清リン濃度，そして血清intact-PTH濃度の三つのパラメータ全てにおいて満たしていた患者は，全体の24.8％であった．調査回答患者の9.8％に認知症合併を認めた．

Background/Aims: Rapid removal of plasma amyloid-beta (A beta) by blood purification may serve as a peripheral A beta sink from the brain for Alzheimer's disease therapy. We investigated the reduction of plasma A beta during hemodialysis and cognitive states. Methods: A beta concentrations and Mini-Mental State Examinations (MMSE) were investigated in 37 hemodialysis patients (68.9 +/- 4.1 years). Results: The dialyzers effectively removed A beta(1-40) and A beta(1-42), 63.9 +/- 14.4 and 51.6 +/- 17.0% at 4 h dialysis, resulting in the reduction of A beta s in whole-body circulation by 51.1 +/- 8.9 and 32.7 +/- 12.0%, respectively. Although the plasma A beta s before dialysis (750.8 +/- 171.3 pg/ml for A beta(1-40)) were higher than those reported for Alzheimer's disease patients, the cognitive states of hemodialysis patients were relatively normal, especially of longer dialysis vintages. Conclusions: Dialyzers effectively reduced A beta s in whole-body circulation. Repeated rapid decrease of plasma A beta s might maintain cognitive state. Copyright (C) 2011 S. Karger AG, Basel

A nationwide statistical survey of 4124 dialysis facilities was conducted at the end of 2008 and 4081 facilities (99.0%) responded. The number of patients undergoing dialysis at the end of 2008 was determined to be 283 421, an increase of 8179 patients (3.0%) compared with that at the end of 2007. The number of dialysis patients per million at the end of 2008 was 2220. The crude death rate of dialysis patients from the end of 2007 to the end of 2008 was 9.8%. The mean age of the new patients begun on dialysis was 67.2 years and the mean age of the entire dialysis patient population was 65.3 years. For the primary diseases of the new patients begun on dialysis, the percentages of patients with diabetic nephropathy and chronic glomerulonephritis were 43.3% and 22.8%, respectively. Among the facilities that measured bacterial count in the dialysate solution in 2008, 52.0% of facilities ensured that a minimum dialysate solution volume of 10 mL was sampled. Among the patients treated by facility dialysis, 95.4% of patients were treated three times a week, and the average time required for one treatment was 3.92 +/- 0.53 (SD) h. The average amounts of blood flow and dialysate solution flow were 197 +/- 31 and 487 +/- 33 mL/min, respectively. The number of patients using a polysulfone membrane dialyzer was the largest (50.7%) and the average membrane area was 1.63 +/- 0.35 m2. According to the classification of dialyzers by function, the number of patients using a type IV dialyzer was the largest (80.3%). The average concentrations of each electrolyte before treatment in patients treated with blood purification by extracorporeal circulation were 138.8 +/- 3.3 mEq/L for serum sodium, 4.96 +/- 0.81 mEq/L for serum potassium, 102.1 +/- 3.1 mEq/L for serum chloride, and 20.7 +/- 3.0 mEq/L for HCO(3)-; the average serum pH was 7.35 +/- 0.05. Regarding the type of vascular access in patients treated by facility dialysis, in 89.7% of patients an arteriovenous fistula was used and in 7.1% an arteriovenous graft was used. The percentage of hepatitis C virus (HCV)-positive patients who were HCV-negative in 2007 was 1.04%; the percentage is particularly high in patients with a period of dialysis of 20 years or longer. The risk of becoming HCV-positive was high in patients with low serum creatinine, serum albumin, and serum total cholesterol levels, and/or a low body mass index before beginning dialysis.

Aggressive removal of circulating free light chains (FLC) by blood purification accompanied by chemotherapy is a promising approach for the treatment of acute renal failure due to myeloma cast nephropathy. Plasma exchange has been performed to remove serum FLC; in order to examine an alternative strategy we performed hemodiafiltration using protein-leaking dialyzers for the treatment of dialysis-dependent acute renal failure due to myeloma cast nephropathy. In the first case with kappa-light chain cast nephropathy, the pre-treatment serum creatinine was 9.65 mg/dL, and the serum kappa-FLC was 27 100 mg/L. Plasma exchange or hemodiafiltration was performed from Monday to Friday during the first several weeks. Chemotherapy was started with high-dose dexamethasone and then switched to bortezomib plus dexamethasone. The mean removal rates of kappa-FLC were 45.8% (one plasma volume) and 66.9% (one-and-a-half plasma volumes) by plasma exchange. The removal rates of kappa-FLC by hemodiafiltration (66.9%, FB210UH beta; 71.6%, PES210D alpha; 75.2%, FXS220) were comparable to those by plasma exchange. In the second case with lambda-light chain cast nephropathy, the pre-treatment serum creatinine was 4.14 mg/dL, and the serum lambda-FLC was 4140 mg/L. The mean removal rates of lambda-FLC were 60.2% (FXS140) and 64.2% (FB210UH beta) by hemodiafiltration. Both cases became dialysis-independent. The combination of an intense blood purification regimen and bortezomib plus dexamethasone therapy appears to be an efficient approach to renal recovery. Hemodiafiltration using protein-leaking dialyzers could become an alternative to plasma exchange as a method of removing FLC.

透析条件・透析量と生命予後の関係を明らかにするため，日本透析医学会の統計調査結果を用いて，後ろ向き・観察的な研究を行った．2002年末の週3回施設血液透析患者を対象に，事故・自殺を除く死亡をエンドポイントとして，患者の透析条件・透析量と2003年末までの1年死亡リスク，および2007年末までの5年死亡リスクについて，ロジスティック回帰分析を行った．2002年末の平均的透析条件は，透析時間239分，血流量（Qb）192 mL/分，ダイアライザ膜面積（膜面積）1.55 m²，透析液流量（Qd）486 mL/分であった．また，尿素の標準化透析量（Kt/V urea）は平均1.32，指数化しない透析量（Kt urea）は平均40.7 Lであった．予後解析の結果，透析時間は240分以上270未満を基準として，それより透析時間が短い患者群で死亡リスクが高く，透析時間が長い患者群で死亡リスクが低い傾向を認めた．Qbは200 mL/分以上220 mL/分未満を基準として，それよりQbが少ない患者群で死亡リスクが高く，Qbが多い患者群で死亡リスクが低い傾向を認めた．膜面積は1.2 m²未満の患者群で死亡リスクが高かったが，それ以外の膜面積と死亡リスクの関係は明確ではなかった．透析量はKt/V urea 1.4以上1.6未満またはKt urea 38.8 L以上42.7 L未満を基準として，それより透析量が少ない患者群では死亡リスクが高く，それより透析量が多い患者群で死亡リスクが低かった．以上の傾向は，残腎機能がないと仮定が可能な，調査時点で透析歴5年以上の患者で顕著であった．一般的な週3回血液透析では，平均的な透析条件・透析量よりも，透析時間の延長やQbの増加によって透析量を増大させることが，患者の生命予後の改善につながる可能性が示唆された．

The Japanese Society for Dialysis Therapy (JSDT) guideline committee, chaired by Dr Y. Tsubakihara, presents the Japanese guidelines entitled "Guidelines for Renal Anemia in Chronic Kidney Disease." These guidelines replace the "2004 JSDT Guidelines for Renal Anemia in Chronic Hemodialysis Patients," and contain new, additional guidelines for peritoneal dialysis (PD), non-dialysis (ND), and pediatric chronic kidney disease (CKD) patients.

The accumulation of amyloid beta (A beta) protein in the brain reflects the cognitive impairment noted in Alzheimer's disease. Recent studies have shown that brain A beta disappeared and cognitive improvement occurred as a result of passive or active A beta immunization. Peripheral administration of nonimmunization substances, such as GM1 ganglioside, also reduced brain A beta. Therefore, we hypothesized that the rapid removal of A beta from the blood by an extracorporeal system may act as a peripheral A beta sink from the brain. In the present study, we investigated the A beta removal activity of medical materials as a first step toward the design of an A beta removal system. First, the removal activities of six materials were studied for A beta(1-40) and A beta(1-42) by batch analysis in albumin solution or in human plasma for 1-16 h. Two of the six materials reduced the A beta concentrations by 90-99% within 1 h. Next, the two effective materials, hexadecyl-alkylated cellulose particles (HDC) and charcoal, were analyzed in a continuous single-pass system with minicolumns. Both materials showed around 81-90% removal activity for more than 2 h, which corresponded to over 4 l of plasma treatment in humans. In a human extracorporeal system, HDC also removed both A beta(1-40) and A beta(1-42) from whole blood circulation. In conclusion, biomedical materials were found that could remove A beta(1-40) and A beta(1-42) effectively in an extracorporeal system. It is now conceivable that further studies can be undertaken to reduce A beta concentrations in the brain to improve cognitive function.