Masatomo Taniguchi

Overview of Regular Dialysis Treatment in Japan (as of 31 December 2008)

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 HCO3‐; 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.

Clinical practice guideline for the management of chronic kidney disease-mineral and bone disorder

Masafumi Fukagawa, Keitaro Yokoyama, Fumihiko Koiwa, Masatomo Taniguchi, Tetsuo Shoji, Junichiro James Kazama, Hirotaka Komaba, Ryoichi Ando, Takatoshi Kakuta, Hideki Fujii, Msasaaki Nakayama, Yugo Shibagaki, Seiji Fukumoto, Naohiko Fujii, Motoshi Hattori, Akira Ashida, Kunitoshi Iseki, Takashi Shigematsu, Yusuke Tsukamoto, Yoshiharu Tsubakihara, Tadashi Tomo, Hideki Hirakata, and Tadao Akizawa for CKD-MBD Guideline Working Group, Japanese Society for Dialysis Therapy

An Overview of Regular Dialysis Treatment in Japan (As of 31 December 2010)

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 20–24 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.

An Overview of Regular Dialysis Treatment in Japan (as of 31 December 2012)

A nationwide statistical survey of 4279 dialysis facilities was conducted at the end of 2012, among which 4238 responded (99.0%). The number of new dialysis patients was 38 055 in 2012. Since 2008, the number of new dialysis patients has remained almost the same without any marked increase or decrease. The number of dialysis patients who died in 2012 was 30 710; a slight decrease from 2011 (30 743). The dialysis patient population has been growing every year in Japan; it was 310 007 at the end of 2012, which exceeded 310 000 for the first time. The number of dialysis patients per million at the end of 2012 was 2431.2. The crude death rate of dialysis patients in 2012 was 10.0%, a slight decrease from that in 2011 (10.2%). The mean age of new dialysis patients was 68.5 years and the mean age of the entire dialysis patient population was 66.9 years. The most common primary cause of renal failure among new dialysis patients was diabetic nephropathy (44.2%). The actual number of new dialysis patients with diabetic nephropathy has been approximately 16 000 for the last few years. Diabetic nephropathy was also the most common primary disease among the entire dialysis patient population (37.1%), followed by chronic glomerulonephritis (33.6%). The percentage of dialysis patients with diabetic nephropathy has been continuously increasing, whereas not only the percentage but also the actual number of dialysis patients with chronic glomerulonephritis has decreased. The number of patients who underwent hemodiafiltration (HDF) at the end of 2012 was 21 725, a marked increase from that in 2011 (14 115). In particular, the number of patients who underwent on‐line HDF increased threefold from 4890 in 2011 to 14 069 in 2012. From the results of the facility survey, the number of patients who underwent peritoneal dialysis (PD) was 9514 and that of patients who did not undergo PD despite having a PD catheter in the abdominal cavity was 347. From the results of the patient survey, among the PD patients, 1932 also underwent another dialysis method using extracorporeal circulation, such as hemodialysis (HD) and HDF. The number of patients who underwent HD at home in 2012 was 393, a marked increase from that in 2011 (327).

An overview of regular dialysis treatment in Japan (as of 31 December 2007).

A nationwide statistical survey of 4098 dialysis facilities was conducted at the end of 2007, and 4052 facilities (98.88%) participated. The number of patients undergoing dialysis at the end of 2007 was determined to be 275 242, an increase of 10 769 patients (4.1%) compared with that at the end of 2006.The number of dialysis patients per million at the end of 2007 was 2154. The crude death rate of dialysis patients at the end of 2007 from the end of 2006 was 9.4%. The mean age of new patients begun on dialysis was 66.8 years and the mean age of the entire dialysis patient population was 64.9 years. For the primary diseases of new patients begun on dialysis, the percentages of patients with diabetic nephropathy and chronic glomerulonephritis were 43.4% and 23.8%, respectively. The percentages of facilities that achieved the control standard of endotoxin concentration in the dialysate solution of <0.05 EU/mL and those that achieved a bacterial count of <100 cfu/mL in the dialysate solution, as specified by the Japanese Society for Dialysis Therapy, were 93.6% and 97.4%, respectively. The percentage of patients positive for the hepatitis C virus antibody among the entire dialysis population significantly decreased from 15.95% at the end of 1999 to 9.83% at the end of 2007. The mean hemoglobin concentration in all the dialysis patients at the end of 2007 was 10.27 (±1.32, SD) g/dL, which has scarcely changed over the last three years. The numbers of male and female patients with a history of hip fracture were 142.9 and 339.0 per 10 000 dialysis patients, respectively, showing an extremely high prevalence among female patients. A history of hip fracture correlates with a low body mass index, serum albumin concentration, and a history of diabetes. The serum creatinine level of patients upon introduction to dialysis was 8.34 (±3.55) mg/dL, and the estimated glomerular filtration rate was 5.43 (±3.43) mL/min/1.73 m2 for the patients who were newly begun on dialysis in 2007.

Overview of Regular Dialysis Treatment in Japan (as of 31 December 2011)

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 38 613 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 30 743 in 2011, which exceeded 30 000 for the first time. The number of patients undergoing dialysis has also been increasing every year; it was 304 856 at the end of 2011, which exceeded 300 000 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 7.19 mg/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.

Overview of Regular Dialysis Treatment in Japan (as of 31 December 2009)

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.

Parathyroidectomy and survival among Japanese hemodialysis patients with secondary hyperparathyroidism

Parathyroidectomy (PTx) drastically improves biochemical parameters and clinical symptoms related to severe secondary hyperparathyroidism (SHPT) but the effect of PTx on survival has not been adequately investigated. Here we analyzed data on 114,064 maintenance hemodialysis patients from a nationwide registry of the Japanese Society for Dialysis Therapy to evaluate the associations of severity of SHPT and history of PTx with 1-year all-cause and cardiovascular mortality. We then compared the mortality rate between 4428 patients who had undergone PTx and 4428 propensity score-matched patients who had not despite severe SHPT. During a 1-year follow-up, 7926 patients of the entire study population died, of whom 3607 died from cardiovascular disease. Among patients without a history of PTx, severe SHPT was associated with an increased risk for all-cause and cardiovascular mortality. However, such an increased risk of mortality was not observed among patients with a history of PTx. In the propensity score-matched analysis, patients who had undergone PTx had a 34% and 41% lower risk for all-cause and cardiovascular mortality, respectively, compared to the matched controls. The survival benefit associated with PTx was robust in several sensitivity analyses and consistent across subgroups, except for those who had persistent postoperative SHPT. Thus, successful PTx may reduce the risk for all-cause and cardiovascular mortality in hemodialysis patients with severe, uncontrolled SHPT.

Phosphate overload directly induces systemic inflammation and malnutrition as well as vascular calcification in uremia

Hyperphosphatemia contributes to increased cardiovascular mortality through vascular calcification (VC) in patients with chronic kidney disease (CKD). Malnutrition and inflammation are also closely linked to an increased risk of cardiovascular death in CKD. However, the effects of Pi overload on inflammation and malnutrition remain to be elucidated. The aim of the present study was to investigate the effects of dietary Pi loading on the interactions among inflammation, malnutrition, and VC in CKD. We used control rats fed normal diets and adenine-induced CKD rats fed diets with different Pi concentrations ranging from 0.3% to 1.2% for 8 wk. CKD rats showed dietary Pi concentration-dependent increases in serum and tissue levels of TNF-α and urinary and tissue levels of oxidative stress markers and developed malnutrition (decrease in body weight, serum albumin, and urinary creatinine excretion), VC, and premature death without affecting kidney function. Treatment with 6% lanthanum carbonate blunted almost all changes induced by Pi overload. Regression analysis showed that serum Pi levels closely correlated with the extent of inflammation, malnutrition, and VC. Also, in cultured human vascular smooth muscle cells, high-Pi medium directly increased the expression of TNF-α in advance of the increase in osteochondrogenic markers. Our data suggest that dietary Pi overload induces systemic inflammation and malnutrition, accompanied by VC and premature death in CKD, and that inhibition of Pi loading through dietary or pharmacological interventions or anti-inflammatory therapy may be a promising treatment for the prevention of malnutrition-inflammation-atherosclerosis syndrome.

Serum phosphate and calcium should be primarily and consistently controlled in prevalent hemodialysis patients.

Mineral metabolism affects mortality in hemodialysis patients and is identified by imbalances in serum phosphate (P), calcium (Ca), and parathyroid hormone (PTH). We examined associations between annual mineral values (P, Ca, PTH) and mortality in a 3‐year cohort (Dec 2006–2009) of 128 125 hemodialysis patients using three models, that is, baseline, time‐dependent and time‐average Cox models. We also examined associations between achieved Japanese guideline targets (P: 3.5−6.0 mg/dL, corrected Ca 8.4−10.0 mg/dL, intact PTH 60−180 mg/dL) and all‐cause survival to elucidate which parameter should be controlled as a priority. High and low serum P (>6.0 or ≤3.5 mg/dL), high Ca (>9.5 mg/dL), higher PTH (>300 pg/mL) and lower PTH (≤60 pg/mL) were significantly associated with high mortality in all three models (P < 0.01). When we examined the association between combination of mineral targets and mortality, patients who achieved all targets simultaneously (20% of subjects, reference) showed lowest mortality. Those who achieved both P and Ca targets showed the same mortality as the reference group. Those who only met P target had a lower risk of death (hazard ratio = 1.17) compared to those that achieved Ca or PTH target (1.41, 1.47, respectively). As time of achieving P and Ca targets increased, all‐cause mortalities diminished incrementally, significantly. Mineral metabolism disorder would lead to high mortality in prevalent hemodialysis patients. Among mineral values, P would be the strongest predictor for high mortality. Consistent achievement of P and Ca targets would lead to good survival.