Predictors of Hyporesponsiveness to Erythropoiesis-Stimulating Agents in Patients with Non-Dialysis-Dependent Chronic Kidney Disease (RADIANCE-CKD Study).

INTRODUCTION: Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) has been associated with increased mortality and cardiovascular events in patients with chronic kidney disease. We hypothesized that the prediction of ESA resistance during ESA administration would be very useful in deciding on a treatment plan. METHODS: Patients enrolled in a randomized controlled trial to evaluate renal prognosis in anemic patients with non-dialysis-dependent chronic kidney disease with hyporesponsiveness to ESA were included; the patients had different target hemoglobin levels. A landmark analysis was performed at 3 months into the study. To construct a predictive model for the severe ESA hypo-responder group, in which there was no increase in hemoglobin even with active treatment, background factors and serum test items that affect anemia at study entry were included in a logistic regression model, the area under the curve (AUC) and 95% confidence intervals (CI) were estimated, and sensitivity and specificity were calculated. This study was a post hoc sub-analysis of a randomized controlled trial. RESULTS: The AUC for the 19 existing risk factors as predictors was 0.783 (95% CI: 0.711-0.855). Among the 19 risk factors, the combination of six factors (hemoglobin level, systolic blood pressure, weight, gender, smoking status, and hypertensive retinopathy) with the largest χ2 statistics were selected by multiple logistics regression. The AUC for these 6 predictors was 0.716 (95% CI: 0.634-0.799). To the six existing risk factors, five serum test items that affect anemia (vitamin B12, vitamin B6, folic acid, parathyroid hormone, and 25-hydroxyvitamin D) were added, for a total of 11 risk factors, with a similar AUC of 0.736 (95% CI: 0.655-0.817), sufficient to predict ESA resistance. CONCLUSIONS: Our results suggest that existing risk factors and serum test items can be used to predict ESA resistance in patients with non-dialysis-dependent chronic kidney disease on ESA.

The efficacy and safety of mizoribine for maintenance therapy in patients with myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis: the usefulness of serum mizoribine monitoring.

BACKGROUND: The life prognosis of elderly patients with myeloperoxidase-anti-neutrophil cytoplasmic antibodies-associated vasculitis (MPO-AAV) has been improved by reducing the corticosteroid or cyclophosphamide dose to avoid opportunistic infection. However, many elderly MPO-AAV patients experience recurrence and renal death. An effective and safer maintenance treatment method is necessary to improve the renal prognosis of MPO-AAV. METHODS: Patients with MPO-AAV who reached complete or incomplete remission after induction therapy were prospectively and randomly divided into mizoribine (MZR; n = 25) and control (n = 28) groups. The primary endpoint was relapse of MPO-AAV. The patients' serum MZR concentration was measured before (C0) and 3 h after taking the MZR. The maximum drug concentration (Cmax) and the serum MZR concentration curves were determined using population pharmacokinetics parameters. We also assessed the relationship between the MZR concentrations and adverse events. The observation period was 12 months. RESULTS: Fifty-eight MPO-AAV patients from 16 hospitals in Japan were enrolled. Ten patients relapsed (MZR group, n = 6; control group, n = 4; a nonsignificant between-group difference). Changes in the serum MZR concentration could be estimated for 22 of the 25 MZR-treated patients: 2 of the 11 patients who reached a Cmax of 3 µg/mL relapsed, whereas 4 of the 11 patients who did not reach this Cmax relapsed. The treatment of one patient with C0 > 1 µg/mL was discontinued due to adverse events. No serious adverse events occurred. CONCLUSION: There was no significant difference in the recurrence rate of MPO-AAV between treatment with versus without MZR.

Elevated Crude Mortality in Obese Chronic Kidney Disease Patients with Loss of Exercise Habit: A Cohort Study of the Japanese General Population.

Objective The relationship between obesity and risk of death in chronic kidney disease (CKD) patients remains controversial. In addition, no clear evidence has been accumulated regarding whether or not exercise improves mortality in CKD patients. Methods The original cohort was based on a Japanese general population of 685,889 people from 40 to 74 years old who had undergone annual specific health checkups. The number of all-cause deaths during follow-up (mean, 4.7 years) in this study was 1,490. Information on walking and exercise habits was obtained by questionnaires. The study population was divided into 4 categories by the combination of CKD and obesity [body mass index (BMI) ≥25.0 kg/m2]. Changes in the BMI and walking and exercise habits were determined by results for the first year and following year. Results Obese CKD patients with weight gain (BMI increase by more than +1.0 kg/m2/year) showed a higher crude mortality (1.32%) than those with a stable BMI (within ±1.0 kg/m2/year; 0.69%). In the obese CKD population, mortality was higher with loss of exercise habits (0.96%) than in those continuously maintaining exercise habits (0.52%). The age- and sex-adjusted hazard ratio for all-cause death was 2.23 in the group with weight gain compared to the group with stable weight (p<0.01) and 2.08 in the group with loss of exercise habits compared to those who maintained exercise habits (p<0.01). Conclusion This observational cohort study suggested that loss of exercise habits as well as weight gain of more than 1 kg/m2/year might worsen all-cause mortality in the obese CKD population.

Weight Loss Improves Liver Dysfunction and Dipstick Proteinuria in Obesity: The Japan Specific Health Checkups Study.

Introduction: Obesity and inappropriate lifestyle is the major risk factors for liver dysfunction and proteinuria. Nevertheless, previous studies have not described the differential impacts of body weight changes and lifestyle modification on already developed liver dysfunction and proteinuria. Methods: The original cohort was 933,490 individuals from the Japanese general population. In this investigation, we included 36,256 obese individuals with elevated levels of aspartate aminotransferase and/or alanine aminotransferase (≥31 IU/L) or positive proteinuria (+/- or more) in both the first and second years. Outcomes were the first normalization of these data defined as improvement in liver dysfunction and proteinuria. Times to outcomes were assessed using the Cox proportional hazards modeling for -1 kg/m2/year change in body mass index (BMI) changes in exercise and alcohol intake. Results: The multivariable-adjusted hazard ratio (HR) for incident improvement in liver dysfunction with BMI change -1.0 kg/m2/year was 1.07 (95% confidence interval [CI] 1.05-1.09) in obesity and that with improved proteinuria was 1.04 (95%CI 1.02-1.07). Compared to subjects without exercise habits, subjects who gained exercise habits exhibited a higher rate of improvement in liver dysfunction (HR 1.08; 95%CI 1.01-1.15) but not in proteinuria (HR 0.98; 95%CI 0.88-1.08). Compared to subjects with continuous alcohol intake habits, subjects who quit alcohol intake also showed a higher rate of improvement in liver dysfunction (HR 1.20; 95%CI 1.09-1.32). Conclusions: This study suggested that weight loss greater than 1 kg/m2/year improves liver dysfunction and dipstick proteinuria in obesity. Particularly, liver dysfunction can be remedied by acquiring an exercise habit and quitting alcohol intake.

ANCA-associated systemic vasculitis in Japan: clinical features and prognostic changes.

BACKGROUND: This study was conducted to standardize treatment and determine patient and renal outcome in Japanese anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis/rapidly progressive glomerulonephritis (AAV/RPGN) patients, because the prognosis of AAV/RPGN patients in Japan had been poor compared with that of other countries. METHODS: The participants in this retrospective cohort study were 824 ANCA-positive RPGN patients, 705 of whom were only myeloperoxidase (MPO)-ANCA positive. RESULTS: Among the early-years cohort (group A; cases diagnosed between 1988 and 1998), patients frequently died due to opportunistic infection. Therefore, we recommended a reduced dose of prednisolone (oral prednisolone dose <0.8 mg/kg/day) with or without cyclophosphamide for initial treatment of Japanese RPGN patients. After this recommendation, 1-year survival of the patients improved: 75% in group A, 79% in group B (between 1999 and 2002), and 81% in group C (after 2003). During the entire observation period, average serum creatinine level at the start of treatment decreased, and improvement of 1-year renal survival was also found (72% in group A, 83% in group B, and 83% in group C), while the recurrence rate was significantly increased in group C (0.05/patient-year in group A, 0.07/patient-year in group B, and 0.13/patient-year in group C). CONCLUSIONS: Oral prednisolone dose <0.8 mg/kg/day with or without cyclophosphamide as an initial treatment could improve patient survival in older Japanese AAV/RPGN patients. However, maintenance treatment avoiding relapse should be established to improve renal outcomes.

Membranous nephropathy with solitary immunoglobulin A deposition.

A 71-year-old woman was admitted with nephrotic syndrome. Light and electron microscopic analyses of renal biopsy tissue showed typical diffuse membranous features. In contrast, granular deposition of immunoglobulin A (IgA), but not IgG, IgM, C3 or C1q, was observed along the capillary walls on immunofluorescence. The patient was pathologically diagnosed with diffuse membranous nephropathy with solitary IgA deposition. Secondary membranous nephropathy was suspected; however, no underlying cause was found. The clinical and pathological findings, except for those of immunofluorescence, were all compatible with a diagnosis of primary membranous nephropathy. This is the first reported case of membranous nephropathy associated with solitary IgA deposition.

Age distribution and yearly changes in the incidence of ESRD in Japan.

BACKGROUND: Although several treatment and screening methods have been tried, the incidence of patients with end-stage renal disease (ESRD) on renal replacement therapy (RRT) continues to increase worldwide. By making a detailed analysis of the major primary renal diseases, we found there have been some favorable effects in the incidence rate of ESRD recently in Japan. METHODS: A total of 339,478 patients in Japan and 909,591 patients in the United States started RRT between 1983 and 1999. We compared trends of average age and incidence rate in each age group with major primary renal diseases and in racial groups after adjusting for general population aging by using a linear regression analysis. RESULTS: All trends in ESRD incidence rates among Japanese, US total, US white, and US black patients showed significant increases (P < 0.001). A significant positive linear relationship between year and mean age at start of RRT also was observed (P < 0.001). After adjustment for general population aging, the mean age increment in Japanese patients with glomerulonephritis was increased significantly, and the proportion of Japanese patients who had glomerulonephritis and were younger than 45 years was decreased, but this decrement was not observed in US patients with glomerulonephritis. CONCLUSION: The reduced number of new patients with ESRD with glomerulonephritis might be caused by early detection and early referral to nephrologists as a result of the Japanese urinalysis-screening program. To reduce the ESRD population, it will be necessary to establish more effective treatment methods to delay exacerbation of progressive renal diseases.

Vascular endothelial growth factor and soluble fms-like tyrosine kinase-1 in septic shock patients treated with direct hemoperfusion with a polymyxin B-immobilized fiber column.

Sepsis is characterized by a systemic inflammatory response to a microbial pathogen. In sepsis, capillary permeability is a tightly regulated feature of microcirculation in all organ beds and is fundamentally altered. We investigated the vascular endothelial growth factor (VEGF) level as a vascular permeability factor and the soluble fms-like tyrosine kinase-1 (Flt-1) level as an antagonist of the VEGF receptors. Serum VEGF and soluble Flt-1 levels in 21 patients with septic shock, who were treated with direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX), were measured by enzyme-linked immunoassay. The VEGF and the soluble Flt-1 levels were more elevated in patients with septic shock than in controls. Between 14 survivors and 7 non-survivors, there was no significant difference in VEGF level before the DHP-PMX therapy, but the soluble Flt-1 level of survivors was significantly lower than that of non-survivors. Although there was no significant difference between starting and ending VEGF levels in survivors, in non-survivors the VEGF level at the end of DHP-PMX therapy was significantly lower than that at the start. In survivors, the soluble Flt-1 level at the end of DHP-PMX therapy was significantly lower than that at the start. On the other hand, in non-survivors, there was no significant difference between the ending and starting soluble Flt-1 levels. The soluble Flt-1 level may be a suitable marker of disease severity and mortality.

Apheresis for MPO-ANCA-associated RPGN-indications and efficacy: lessons learned from Japan nationwide survey of RPGN.

A national survey concerning rapidly progressive glomerulonephritis (RPGN) was conducted in Japan between 1989 and 2000 and resulted in the registration of 715 patients with RPGN. Among the documented patients, the most frequent primary disease was primary pauci-immune crescentic glomerulonephritis (n = 283), and the second most frequent was microscopic polyangitis (n = 127). Overall, 370 patients had MPO-ANCA, and 23 patients had PR3-ANCA. We found that both renal and patient survivals were significantly worse in patients with MPO-ANCA-associated RPGN than patients with PR3-ANCA. Fifty-three patients received apheresis therapy with various combinations of immunosuppressive regimens. They had higher serum creatinine, higher CRP, and a higher frequency of complicated pulmonary involvements as compared to the controls without apheresis therapy. In dialysis-dependent patients, no additional benefit from apheresis therapy was observed. Only pulmonary renal syndrome patients with CRP > 6 mg/dl at presentation showed a slightly better prognosis (patient survival with apheresis; 66.7%, without apheresis; 56.7%). Furthermore, a rapid MPO-ANCA titer reduction was observed in patients treated with apheresis. Patients with MPO-ANCA-associated RPGN were older, and had more chronic and sclerotic lesions than patients with PR3-ANCA-associated RPGN. Based on these findings, we suggest that a lower dose of immunosuppressant should be considered in order to avoid opportunistic infection. In this situation, cytapheresis is the treatment of choice. Nevertheless, in patients with an aggressive form of RPGN with rapid deterioration of renal function like the PR3-ANCA-associated RPGN, or pulmonary renal syndrome complicated severe inflammation, or relapses with high MPO-ANCA titer, we conclude that apheresis therapy should be considered.