Modified Creatinine Index and the Risk of Bone Fracture in Patients Undergoing Hemodialysis: The Q-Cohort Study.

BACKGROUND: Hemodialysis patients are at increased risk for bone fracture and sarcopenia. There is close interplay between skeletal muscle and bone. However, it is still unclear whether lower skeletal muscle mass increases the risk for bone fracture. STUDY DESIGN: Cross-sectional study and prospective longitudinal cohort study. SETTING & PARTICIPANTS: An independent cohort of 78 hemodialysis patients in the cross-sectional study and 3,030 prevalent patients undergoing maintenance hemodialysis prospectively followed up for 4 years. PREDICTOR: Skeletal muscle mass measured by bioelectrical impedance analysis (BIA) and modified creatinine index, an estimate of skeletal muscle mass based on age, sex, Kt/V for urea, and serum creatinine level. OUTCOMES: Bone fracture at any site. RESULTS: In the cross-sectional study, modified creatinine index was significantly correlated with skeletal muscle mass measured by BIA. During a median follow-up of 3.9 years, 140 patients had bone fracture. When patients were divided into sex-specific quartiles based on modified creatinine index, risk for bone fracture estimated by a Fine-Gray proportional subdistribution hazards model with all-cause death as a competing risk was significantly higher in the lower modified creatinine index quartiles (Q1 and Q2) compared to the highest modified creatinine index quartile (Q4) as the reference value in both sexes (multivariable-adjusted HRs for men were 7.81 [95% CI, 2.63-23.26], 5.48 [95% CI, 2.08-14.40], 2.24 [95% CI, 0.72-7.00], and 1.00 [P for trend < 0.001], and for women were 4.44 [95% CI, 1.50-13.11], 2.33 [95% CI, 0.86-6.31], 1.96 [95% CI, 0.82-4.65], and 1.00 [P for trend = 0.007] for Q1, Q2, Q3, and Q4, respectively). LIMITATIONS: One-time assessment of modified creatinine index; no data for residual kidney function and fracture sites and causes. CONCLUSIONS: Modified creatinine index was correlated with skeletal muscle mass measured by BIA. Lower modified creatinine index was associated with increased risk for bone fracture in male and female hemodialysis patients.

The Fukuoka Kidney disease Registry (FKR) Study: design and methods.

BACKGROUND: Chronic kidney disease (CKD) is an established independent risk factor for progression to end-stage renal disease (ESRD) and incidence of cardiovascular disease (CVD). The onset and progression of CKD are associated with both genetic predisposition and various lifestyle-related factors, but little is known about the influence of genetic-environmental interactions on the incidence of ESRD or CVD in patients with CKD. METHODS: The Fukuoka Kidney disease Registry (FKR) Study is designed as one of the largest prospective, multicenter, observational cohort studies in non-dialysis dependent CKD patients. The FKR Study aims to enroll approximately 5000 individuals at multiple clinical centers and follow them for up to at least 5 years. At baseline, subjects enrolled in the FKR Study will fill out extensive lifestyle-related questionnaires. Further, their health status and treatments will be monitored annually through a research network of nephrology centers. Blood and urine samples, including DNA/RNA, will be collected at the time of enrolment and every 5-years follow-up. CONCLUSIONS: The FKR Study will provide many insights into the onset and progression of CKD, which will suggest hypothesis-driven interventional clinical trials aimed at reducing the burden of CKD. The features of the FKR Study may also facilitate innovative research to identify and validate novel risk factors, including genetic susceptibility and biomarkers, using biomaterials by high-throughput omics technologies.

Association Between Serum Phosphate Levels and Stroke Risk in Patients Undergoing Hemodialysis: The Q-Cohort Study.

BACKGROUND AND PURPOSE: The contribution of serum phosphate levels to stroke risk in dialysis patients remains unclear. The present study aimed to elucidate the respective association between serum phosphate levels and the risk of brain hemorrhage or infarction in patients undergoing hemodialysis. METHODS: A total of 3437 patients undergoing hemodialysis were followed up for a median of 3.9 years. The primary outcome was the occurrence of brain hemorrhage or infarction. Patients were divided into 4 groups based on their baseline serum phosphate levels (Q1-Q4). Stroke risk was estimated using a Cox proportional hazards model. RESULTS: During the follow-up period, 75 patients experienced brain hemorrhage and 139 experienced brain infarction. The risk of brain hemorrhage was significantly higher in the highest (Q4) compared with the lowest quartile (Q1) as the reference value (multivariate-adjusted hazard ratio [95% confidence intervals]: Q1, 1.00; Q2, 1.76 [0.79-4.18]; Q3, 1.99 [0.92-4.67]; and Q4, 2.74 [1.27-6.47]; P=0.077 for trend; hazard ratio for every 1 mmol/L increase in serum phosphate level, 2.07 [1.10-3.81]; P=0.025). In contrast, the risk of brain infarction was significantly higher in Q1 (P=0.045) compared with Q3 as the reference value (Q1, 1.65 [1.01-2.73]; Q2, 1.35 [0.82-2.25]; Q3, 1.00; and Q4, 1.30 [0.77-2.20]). CONCLUSIONS: Higher serum phosphate levels were associated with an increased risk of brain hemorrhage, whereas low levels were associated with an increased risk of brain infarction in hemodialysis patients. These results suggest the importance of managing serum phosphate levels within an appropriate range in hemodialysis patients. CLINICAL TRIAL REGISTRATION: URL: http://www.umin.ac.jp/. Unique identifier: UMIN000000556.

Health-related quality of life of predialysis patients with chronic renal failure.

BACKGROUND: Health-related quality of life (HQOL) of predialysis patients with chronic renal failure (CRF) has received less attention than that of dialysis patients. We investigated changes in SF-36 over 1 year and examined associations between clinical parameters and SF-36 in predialysis CRF patients. METHODS: Subjects were 471 predialysis CRF patients. SF-36 and clinical parameters were measured every 8 weeks for 48 weeks. Of the 471 subjects, 294 underwent one or more follow-ups. We analyzed the pooled dataset of the 294 CRF patients and 2002 subjects from Japanese general population using analysis of covariance. RESULTS: After adjustment for age and sex, the 1-year declines in SF-36 domains were significantly greater in the predialysis patients than in the general population. For a 10% decline in hematocrit from the baseline survey value, the decline in vitality of SF-36 was 4.5 points (p = 0.003), while for a 10% increase in serum creatinine from the baseline survey value, respective declines in physical functioning, role-physical and mental health were 1.2 (p = 0.004), 1.9 (p = 0.035), and 1.0 points (p = 0.008). CONCLUSION: Among these predialysis CRF patients, the decline in HQOL was faster than that in the general population, and was associated with an increase in serum creatinine and decline in hematocrit.

Expression of synaptopodin and GLEPP1 as markers of steroid responsiveness in primary focal segmental glomerulosclerosis.

The crucial involvement of podocyte failure in the development of hereditary focal segmental glomerulosclerosis (FSGS) indicates that specific podocyte proteins are closely related to podocyte function and biology. We hypothesized that podocyte failure, reflected by alteration of these proteins, leads not only to FSGS but also to resistance to steroid therapy. We investigated the association between expression of synaptopodin and glomerular epithelial protein 1 (GLEPP1) and response to corticosteroid therapy in primary FSGS. The subjects of this retrospective study were 17 adult patients with primary FSGS with nephrotic syndrome (NS) seen at Fukuoka Red Cross Hospital between 1979 and 2001. They were divided into two groups according to the response to steroid therapy at 6months: responders (n=10) and non-responders (persistence of nephrotic-range proteinuria, n=7). Expression levels of synaptopodin and GLEPP1 were examined immunohistochemically using image analysis software. Low expression levels of both proteins were associated with poor steroid responsiveness in FSGS. The average gray values for synaptopodin and GLEPP1 expression in responders vs. non-responders were 9.0+/-0.7 (mean+/-S.E.M.) vs. 6.3+/-0.9 (P=0.04) and 9.6+/-1.2 vs. 6.0+/-1.0 (P=0.04), respectively. The percentages of glomerular area staining for synaptopodin and GLEPP1 in responders vs. non-responders were 15.4+/-2.7% vs. 8.1+/-1.2% (P=0.045) and 11.9+/-1.6% vs. 6.0+/-1.3% (P=0.02), respectively. Synaptopodin expression correlated with the severity of proteinuria and with GLEPP1 expression. Reduced expression of both synaptopodin and GLEPP1 is associated with poor response to steroid therapy in primary FSGS.

Effects of Lowering Dialysate Calcium Concentration on Mineral and Bone Disorders in Chronic Hemodialysis Patients: Conversion from 3.0 mEq/L to 2.75 mEq/L.

Selection of a lower dialysate calcium concentration (DCa) can reduce calcium burden and prevent vascular calcification in hemodialysis patients. However, decreased DCa can worsen mineral and bone disorders. This 1-year retrospective observational study evaluated 121 hemodialysis patients at Fukuoka Renal Clinic who underwent conversion of DCa from 3.0 mEq/L to 2.75 mEq/L. The primary outcomes were changes in serum levels of calcium, phosphate, and parathyroid hormone (PTH). The effects of baseline serum calcium and PTH levels on changes in biochemical parameters were also determined. One year after DCa conversion, mean serum calcium level decreased, while serum phosphate, alkaline phosphatase, and PTH concentrations increased. The rate of achievement of target PTH was higher in patients with lower serum PTH level at baseline, while patients with higher baseline serum PTH level tended to exceed the upper limit of the PTH target range. Patients with higher baseline serum calcium concentration showed a greater decrease in serum calcium level and a greater increase in serum PTH level at 1 year. Patients with a lower baseline serum PTH level can benefit from optimal PTH control following conversion of DCa from 3.0 mEq/L to 2.75 mEq/L. However, secondary hyperparathyroidism may be exacerbated in some patients with higher baseline serum calcium (Ca) and PTH levels. These results indicate that an individualized approach can maximize the benefits of Ca unloading after conversion to lower DCa.

Stroke in patients on maintenance hemodialysis: a 22-year single-center study.

BACKGROUND: Few studies have reported the detailed clinical features of stroke in patients with end-stage renal disease. We examined the frequency of the subtypes, mechanism, and outcome of stroke in patients receiving hemodialysis (HD). METHODS: We studied 151 consecutive patients who developed an acute stroke among the maintenance HD population in our kidney center during 22 years, divided into the initial 17-year (n = 61) and the more recent 5-year (n = 90) groups. For purposes of comparison, we also studied 1,017 stroke patients with normal renal function. RESULTS: Stroke patients receiving HD were younger (age, 64 +/- 10 versus 67 +/- 13 years; P < 0.02) and more frequently had hypertension (87% versus 43%; P < 0.0001) and diabetes (53% versus 23%; P < 0.0001) compared with stroke patients with normal renal function. In the initial HD group, brain hemorrhage was the major subtype of stroke (52%), whereas in the more recent group, brain infarction (BI) replaced hemorrhage as the leading subtype (68%; P < 0.005). In patients with BI, large-artery atherosclerosis was more prevalent in the more recent group than in the initial HD group (33% versus 12%; P < 0.05). A vertebrobasilar territory infarct was more prevalent for HD patients than for those with normal renal function (48% versus 33%; P < 0.05). BI (especially large-artery atherosclerosis and cardioembolism) occurred more frequently during or less than 30 minutes after the dialysis procedure (34%) than brain hemorrhage (19%; P < 0.05). Receiving HD was an independent indicator for poor functional outcome and mortality after stroke. CONCLUSION: In our maintenance HD population, stroke showed several unique characteristics compared with the control population, including a predominance of vertebrobasilar arterial territory infarcts. The dialysis procedure itself seems to be associated more frequently with ischemic rather than hemorrhagic strokes.

Hyporesponsiveness to erythropoiesis-stimulating agent as a prognostic factor in Japanese hemodialysis patients: the Q-Cohort study.

BACKGROUND: Previous epidemiological evidence has suggested that responsiveness to erythropoiesis-stimulating agents (ESAs) is related to prognosis in hemodialysis (HD) patients. We investigated the effects of hyporesponsiveness to ESA on mortality and cardiovascular events in Japanese HD patients, taking modifying factors into account. METHODS: A total of 2,905 Japanese HD patients aged ≥18 years who received ESA treatment were prospectively followed up for 4 years. Responsiveness to ESA was estimated using an erythropoietin resistance index (ERI), defined as erythropoietin dosage per week divided by post-HD weight and hemoglobin value (U/kg/week/g/dl). Patients were divided into three groups by tertiles of ERI levels: low ERI, ≤5.10; intermediate ERI, 5.11-9.43; high ERI, ≥9.44. Risk estimates were calculated by a Cox proportional hazards model, adjusting for potential confounders. RESULTS: During follow-up, 482 patients died from any causes. The 4-year survival rate decreased linearly with higher ERI levels, being 87.5, 82.9, and 72.0% for low, intermediate, and high ERI group (p for trend <0.001). Compared with the low ERI group, the multivariate-adjusted hazard ratio (mHR) was significantly higher in the high ERI group [mHR, 1.64 (95% confidence interval, 1.27-2.11)]. In the high ERI group, patients with Kt/V ≥ 1.57 had a significantly lower risk of death from any causes compared with those with Kt/V ≤ 1.56 [mHR, 0.73 (0.54-0.98)]. CONCLUSION: Our findings suggest that ESA responsiveness can be considered a significant prognostic factor in Japanese HD patients.

Two Years of Cinacalcet Hydrochloride Treatment Decreased Parathyroid Gland Volume and Serum Parathyroid Hormone Level in Hemodialysis Patients With Advanced Secondary Hyperparathyroidism.

The long-term effect of cinacalcet hydrochloride treatment on parathyroid gland (PTG) volume has been scarcely investigated in patients with moderate to advanced secondary hyperparathyroidism (SHPT). The present study was a prospective observational study to determine the effect of cinacalcet treatment on PTG volume and serum biochemical parameters in 60 patients with renal SHPT, already treated with intravenous vitamin D receptor activator (VDRA). Measurement of biochemical parameters and PTG volumes were performed periodically, which were analyzed by stratification into tertiles across the baseline parathyroid hormone (PTH) level or PTG volume. We also determined the factors that can estimate the changes in PTG volume and the achievement of the target PTH range by multivariable analyses. Two years of cinacalcet treatment significantly decreased the serum levels of PTH, calcium, and phosphate, followed by the improvement of achieving the target ranges for these parameters recommended by the Japanese Society for Dialysis Therapy. Cinacalcet decreased the maximal and total PTG volume by about 30%, and also decreased the serum PTH level independent of the baseline serum PTH level and PTG volume. Ten out of 60 patients showed 30% increase in maximal PTG after 2 years. Multivariable analysis showed that patients with nodular PTG at baseline and patients with higher serum calcium and PTH levels at 1 year were likely to exceed the target range of PTH at two years. In conclusion, cinacalcet treatment with intravenous VDRA therapy decreased both PTG volume and serum intact PTH level, irrespective of the pretreatment PTG status and past treatment history.

Dietary patterns and clinical outcomes in hemodialysis patients in Japan: a cohort study.

BACKGROUND & OBJECTIVES: Little is known about actual dietary patterns and their associations with clinical outcomes in hemodialysis patients. We identified dietary patterns in hemodialysis patients in Japan and examined associations between dietary patterns and clinical outcomes. DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS: We used data from 3,080 general-population participants in the Hisayama study (year 2007), and data from 1,355 hemodialysis patients in the Japan Dialysis Outcomes and Practice Patterns Study (JDOPPS: years 2005-2007). Food intake was measured using a brief self-administered diet-history questionnaire (BDHQ). To identify food groups with the Hisayama population data, we used principal components analysis with Promax rotation. We adjusted the resulting food groups for total daily energy intake, and then we used those adjusted food-group scores to identify dietary patterns in the JDOPPS patients by cluster analysis (Ward's method). We then used Cox regression to examine the association between dietary patterns and a composite of adverse clinical outcomes: hospitalization due to cardiovascular disease or death due to any cause. RESULTS: We identified three food groups: meat, fish, and vegetables. Using those groups we then identified three dietary patterns: well-balanced, unbalanced, and other. After adjusting for potential confounders, we found an association between an unbalanced diet and important clinical events (hazard ratio 1.90, 95% C.I. 1.19-3.04). CONCLUSIONS: Hemodialysis patients whose diet was unbalanced were more likely to have adverse clinical outcomes. Thus hemodialysis patients might benefit not only from portion control, but also from a diet that is well-balanced diet with regard to the food groups identified here as meat, fish, and vegetables.

Steroid responsiveness and frequency of relapse in adult-onset minimal change nephrotic syndrome.

To clarify factors influencing the response to corticosteroids and subsequent relapses, 62 Japanese adult patients with minimal change nephrotic syndrome were analyzed retrospectively. Five patients experienced remission spontaneously. Fifty-three patients entered complete remission, 3 patients entered partial remission, and 1 patient showed no response to corticosteroids. Fifty-three patients with complete remission were divided into two groups: 38 early responders who experienced remission completely within 8 weeks after starting treatment and 15 late responders who experienced remission after 8 weeks. Blood urea nitrogen and serum creatinine levels and proteinuria selectivity index at presentation were significantly worse in late than early responders. Relative interstitial volume determined by the point-counting method was significantly greater in late than early responders. Relative interstitial volume showed significant correlations with blood urea nitrogen, serum creatinine, and proteinuria selectivity index values. Thirty-three patients experienced a relapse; 13 patients experienced multiple relapses. Fifty-three patients with remission were divided into three groups: 16 patients who experienced relapse within 6 months after the initial response (early relapsers), 17 patients who experienced relapse after 6 months (late relapsers), and 20 patients who did not experience relapse (nonrelapsers). Mean age at onset was younger in early relapsers than late or nonrelapsers. Age at onset correlated inversely with relapse rate in 53 patients with remission and correlated positively with timing of the first relapse in 33 relapsers. It thus was suggested that impaired renal function and poor selectivity of proteinuria, which might be related to interstitial edema, were factors influencing a slower response to corticosteroids. Younger patients had a greater incidence of relapse and were prone to experience relapse earlier.

Controlled, prospective trial of steroid treatment in IgA nephropathy: a limitation of low-dose prednisolone therapy.

BACKGROUND: No accepted therapy has been established for progressive immunoglobulin A (IgA) nephropathy. METHODS: A prospective, randomized, controlled trial of low-dose prednisolone therapy was performed in patients with IgA nephropathy with moderate histological characteristics. Forty-three patients in the steroid group and 47 patients in the control group were included in the study. The initial dose of prednisolone was 20 mg/d, gradually tapered to 5 mg/d during 2 years. RESULTS: Baseline urine protein-creatinine ratio (UP-UCR) was significantly greater in the steroid group than in controls. Follow-up duration was 65 +/- 25 months in the steroid group and 64 +/- 23 months in controls. Changes in UP-UCR from baseline, ie, UP-UCR at last follow-up minus UP-UCR at baseline, were significantly lower in the steroid group than in controls (steroid group, -0.84 +/- 1.78; controls, 0.26 +/- 1.65; P = 0.0034). Kidney survival was similar in both groups. Patients were divided into two subgroups according to clinical course. There were 28 improved patients and 15 unimproved patients in the steroid group and 27 improved patients and 20 unimproved patients in the control group. In the steroid group, UP-UCR was significantly greater in the unimproved than improved subgroup (3.1 +/- 2.6 versus 1.8 +/- 1.5). CONCLUSION: These data suggest that our protocol had an antiproteinuric effect, but could not improve kidney survival. Because the effect of steroid therapy to prevent the progression of IgA nephropathy is believed to be linked closely to reduction in urinary protein, an insufficient dose of prednisolone in our protocol may be the reason for the discrepancy between the effect on proteinuria and kidney survival.

Dialysis-related hypotension as a cause of progressive frontal lobe atrophy in chronic hemodialysis patients: a 3-year prospective study.

BACKGROUND/AIM: Brain atrophy is known to develop more rapidly in hemodialysis (HD) patients than other individuals. The present study was designed to examine the role of HD-related hypotension in brain atrophy in patients on chronic HD. METHODS: By using magnetic resonance imaging, whole brain atrophy was assessed by the ventricular-brain ratio (VBR; ventricular area/whole brain area). Frontal brain atrophy was assessed by the frontal atrophy index (FAI; frontal brain area/intracranial frontal space). The number of lacunae was also counted. We studied 32 HD patients without symptomatic neurological abnormalities or diabetes mellitus: male/female ratio 19/13; mean age +/- SD 53 +/- 10 (range 28-77) years; mean HD duration +/- SD 11 +/- 6 (range 1-22) years. Magnetic resonance imagings were taken in 1995 and 1998. All dialysis-related hypotension episodes during the same period were identified from the medical records and counted. RESULTS: The VBR ranged from 8.8 to 18.7% in 1995 (12.8 +/- 2.2%) and was not different in 1998 (13.1 +/- 2.7%). However, the VBR increased by more than 5% in 14 patients, and their HD duration of 13 +/- 6 years was significantly longer than that of 18 patients with stable VBR (p < 0.05). The FAI in 1995 was 62.2 +/- 4.2% (range 55.8-71.3%) and decreased significantly to 59.7 +/- 4.7% (range 50.2-70.9%) in 1998 (p < 0.05). The change in FAI correlated significantly with both the total number of dialysis-related hypotension episodes (r = 0.45, p < 0.05) and the increase in number of lacunae (r = 0.42, p < 0.05). CONCLUSION: Our results suggest that dialysis-related hypotension plays a role in progressive frontal lobe atrophy in HD patients.

Heterochronic spontaneous rupture of bilateral renal cell carcinomas in a hemodialysis patient.

A 64-year-old man undergoing chronic hemodialysis was admitted under a shock state with macrohematuria and fatigue lasting for two hours. A blood analysis revealed severe anemia. Computed tomography disclosed a large right-sided perirenal hematoma. The patient was successfully treated with radical nephrectomy, leading to a histological diagnosis of spontaneous rupture of renal cell carcinoma (RCC). One year after rupture of the right RCC, he again developed macrohematuria and computed tomography revealed a left-sided perirenal hematoma. Radical nephrectomy followed by a histological examination revealed spontaneous rupture of the left-sided RCC. This case emphasizes the importance of conducting periodic imaging evaluations of chronic hemodialysis patients with renal cystic masses.

Kienböck's disease: unusual cause of acute onset wrist pain in a dialysis patient.

Kienböck's disease is a rare disorder that presents with wrist pain and limitation of motion and is caused by avascular necrosis of the lunate bone. Dialysis patients occasionally present with wrist pain. However, Kienböck's disease is rarely reported in dialysis patients. We report a case of 52-year-old woman with a 28-year history of hemodialysis who presented with acute wrist pain. T1-weighted magnetic resonance imaging showed diffuse low intensity of the lunate bone, consistent with the diagnosis of Kienböck's disease. Because this disease can lead to chronic debilitating wrist pain, prompt diagnosis, accurate staging, and provision of appropriate treatment is mandatory.

Does cinacalcet improve the prognosis of dialysis patients?

Appropriate control of serum calcium (Ca) and inorganic phosphate (Pi) levels is required for better prognosis of dialysis patients. Cinacalcet is known to reduce not only serum parathyroid hormone (PTH) but also Ca and Pi levels; however, it remains unclear whether cinacalcet can ultimately improve the prognosis of such patients. In this paper, the ongoing prospective observational study (Q Cohort Study) and double-blind randomized controlled study (EVOLVE Study) are introduced. In the Q Cohort Study, cinacalcet therapy is indicated when intact PTH levels exceed 180 pg/mL, accounting for 31.3% of the study population (N = 3009). In the EVOLVE Study, the primary endpoint is the time to occurrence of composite events including all-cause mortality or nonfatal cardiovascular events. There is a related pilot study that treated patients over a 6-month period with cinacalcet. The findings showed that cinacalcet reduced serum PTH, Ca, and Pi levels and that if the patient had lower PTH levels at baseline, the dosage of vitamin D could be greatly reduced. Thus, in some patients concomitant vitamin D and cinacalcet therapy may be preferred to vitamin D alone.