Proton Pump Inhibitors and Hyporesponsiveness to Erythropoiesis-Stimulating Agents in Hemodialysis Patients: Results from the Japan Dialysis Outcomes and Practice Patterns Study.

INTRODUCTION: Hyporesponsiveness to erythropoiesis stimulating agents (ESAs) is important problem in dialysis patients. While proton pump inhibitors (PPIs) may inhibit iron absorption, few studies have examined associations between PPIs and ESA-resistant anemia in hemodialysis patients. This study examined the associations between PPIs and ESA-resistant anemia in hemodialysis patients. METHODS: The present study was a cross-sectional study using repeated 4-month observations, up to eight observations/patient, from the Japan Dialysis Outcomes and Practice Patterns Study (J-DOPPS). The primary outcome was erythropoietin resistance index (ERI). ESA dose, hemoglobin, proportion of erythropoietin-resistant anemia, transferrin saturation (TSAT), and ferritin were also examined. Linear or risk-difference regression models were used with generalized estimating equations to account for repeated measurements. RESULTS: Of 1,644 patients, 867 patients had PPI prescriptions (52.7%). Patients prescribed PPI had higher ERI, higher ESA dose, and lower TSAT levels. Multivariable analysis for 12,048 four-month observations showed significantly greater ERI in PPI users (adjusted difference 0.95 IU/week/kg/[g/dL] [95% CI: 0.40-1.50]). Significant differences were also found in ESA dose (336 IU/week [95% CI: 70-602]) and the prevalence of erythropoietin-resistant anemia (3.9% [2.0-5.8%]) even after adjusted for TSAT and ferritin. Among possible mediators between the association of PPIs and anemia, TSAT was significantly different between PPI users and non-users (adjusted difference, -0.82% [95% CI: -1.56 to -0.07]). CONCLUSIONS: This study showed the associations between PPI and ERI, ESA dose, and TSAT in hemodialysis patients; physicians should consider anemia's associations with PPIs in hemodialysis patients.

Relationship between serum calcium or phosphate levels and mortality stratified by parathyroid hormone level: an analysis from the MBD-5D study.

INTRODUCTION: There is limited evidence about the association between calcium and phosphate levels and mortality stratified by intact parathyroid hormone (iPTH) level. METHODS: We investigated whether differences in iPTH level affect the relationship between calcium and phosphate levels and all-cause mortality in hemodialysis patients with secondary hyperparathyroidism (SHPT). Calcium and phosphate levels were categorized as low (< 8.5 mg/dL, < 4.0 mg/dL), medium (≥ 8.5-< 9.5 mg/dL, ≥ 4.0-< 7.0 mg/dL), and high (≥ 9.5 mg/dL, ≥ 7.0 mg/dL), respectively. iPTH levels were grouped into < 300 or ≥ 300 pg/mL. Adjusted incidence rate ratios (aIRRs) were analyzed by weighted Poisson regression. RESULTS: For calcium, patients with higher iPTH (≥ 300 pg/mL) had significantly higher all-cause mortality rates in the high than in the medium category (aIRR 1.99, 95% confidence interval [CI] 1.16-3.42), and tended to have a higher mortality rate in the low category (aIRR 2.04, 95% CI 0.94-4.42). Patients with lower iPTH (< 300 pg/mL) had higher mortality rates in the high than in the medium category (aIRR 1.65, 95% CI 1.39-1.96). For phosphate, the mortality rate was significantly higher in the high than in the medium category in patients with higher and lower iPTH (aIRR 3.23, 95% CI 1.63-6.39 for iPTH ≥ 300 pg/mL; aIRR 1.58, 95% CI 1.06-2.36 for iPTH < 300 pg/mL). CONCLUSION: High calcium and phosphate levels were associated with increased risk of mortality irrespective of iPTH level.

Changes in 3-month mineral and bone disorder patterns were associated with all-cause mortality in prevalent hemodialysis patients with secondary hyperparathyroidism.

BACKGROUND: There is limited evidence on the association between short-term changes in mineral and bone disorder parameters and survival in maintenance hemodialysis patients. METHODS: We investigated the association between changing patterns of phosphorus, calcium and intact parathyroid hormone levels and all-cause mortality in hemodialysis patients with secondary hyperparathyroidism. Each parameter was divided into three categories (low [L], middle [M] and high [H]), and the changing patterns between two consecutive visits at 3-month intervals were categorized into nine groups (e.g., L-L and M-H). The middle category was defined as 4.0-7.0 mg/dL for phosphorous, 8.5-9.5 mg/dL for calcium and 200-500 pg/mL for intact parathyroid hormone. Adjusted incidence rates and rate ratios were analyzed by weighted Poisson regression models accounting for time-dependent exposures. RESULTS: For phosphorus, shifts from low/high to middle category (L-M/H-M) were associated with a lower mortality compared with the L-L and H-H groups, whereas shifts from middle to low/high category (M-L/M-H) were associated with a higher mortality compared with the M-M group. For calcium, shifts from low/middle to high category (L-H/M-H) were associated with a higher mortality compared with the L-L and M-M groups, whereas shifts from high to middle category (H-M) were associated with a lower mortality compared with the H-H group. For intact parathyroid hormone, shifts from low to middle category (L-M) were associated with a lower mortality compared with the L-L group. CONCLUSIONS: Changes in the 3-month patterns of phosphorus and calcium toward the middle category were associated with lower mortality. Our study also suggests the importance of avoiding hypercalcemia.

Level of Low Back Pain-Related Disability Is Associated with Risk of Subsequent Falls in an Older Population: Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS).

OBJECTIVES: To examine the longitudinal association between baseline disability due to low back pain (LBP) and future risk of falls, particularly significant falls requiring treatment, in a community-dwelling older population. METHODS: This was a prospective population-based cohort study using data from the Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS; 2008-2010). A total of 2,738 residents aged ≥60 years were enrolled. LBP was assessed using the Roland-Morris Disability Questionnaire (RMDQ), and the level of LBP-related disability was divided into three categories (none, low, and medium to high). Incidence of falls over the following year was determined using a self-reported questionnaire after the one-year follow-up period. The risk ratio (RR) for LBP-related disability associated with any fall and any fall requiring treatment was estimated using log binomial regression models. RESULTS: Data were analyzed for 1,358 subjects. The prevalence of LBP at baseline was 16.4%, whereas 122 (8.9%) participants reported a low level of LBP-related disability and 101 (7.4%) reported medium to high levels of LBP-related disability. Incidence of any fall and falls requiring treatment was reported by 22.1% and 4.6% of participants, respectively. Subjects with medium to high levels of disability were more likely to experience subsequent falls (adjusted RR = 1.53, 95% confidence interval [CI] = 1.21-1.95) and falls requiring treatment (adjusted RR = 2.55, 95% CI = 1.41-4.60) than those with no LBP-related disability. CONCLUSIONS: Level of LBP-related disability was associated with an increased risk of serious falls in a general population of community-living older adults. These findings can alert health care providers involved in fall prevention efforts to the important issue of activity-related disability due to LBP.

Interactive Effectiveness of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers or Their Combination on Survival of Hemodialysis Patients.

BACKGROUND: Does the use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers individually or as a combination confer a survival benefit in hemodialysis patients? The answer to this question is yet unclear. METHODS: We performed a case-cohort study using data from the Mineral and Bone Disorder Outcomes Study for Japanese CKD stage 5D patients (MBD-5D), a 3-year multicenter prospective case-cohort study, including 8,229 hemodialysis patients registered from 86 facilities in Japan. All patients had secondary hyperparathyroidism, a condition defined as a parathyroid hormone level ≥180 pg/mL and/or receiving vitamin D receptor activators. We compared all-cause mortality rates between those receiving ACEI, ARB, and their combination and non-users with interaction testing. We used marginal structural Poisson regression (causal model) to estimate the causal effect and interaction adjusted for possible time-dependent confounding. Cardiovascular mortality was also evaluated. RESULTS: Among 3,762 randomly sampled subcohort patients, those taking ACEI, ARB, and their combination at baseline accounted for 4.0, 31.6, and 3.8%, respectively. Over 3 years, 1,226 all-cause and 462 cardiovascular deaths occurred. Compared to non-users, ARB-alone users had a lower all-cause mortality rate (adjusted incident rate ratio [aIRR] 0.62, 95% CI 0.50-0.76), whereas ACEI-alone users showed a statistically similar rate (aIRR 1.01, 95% CI 0.57-1.77). On the contrary, combination users had a greater mortality rate (aIRR 2.56, 95% CI 1.22-5.37), showing significant interaction (p = 0.03). Analysis for cardiovascular mortality showed similar results. CONCLUSION: Among hemodialysis patients with secondary hyperparathyroidism, unlike ACEI use, ARB use was associated with greater survival than non-use. Conversely, combination use was associated with greater mortality. Controlled trials are warranted to verify the causality factors of these associations.

Frequent monitoring of mineral metabolism in hemodialysis patients with secondary hyperparathyroidism: associations with achievement of treatment goals and with adjustments in therapy.

Background: Dialysis guidelines in Japan recommend more frequent measurement of mineral metabolism markers than the Kidney Disease: Improving Global Outcomes guidelines. However, the extent to which frequent marker measurement contributes to achievement of target ranges and to therapy adjustment is unknown. Methods: This multicenter cohort study involved 3276 hemodialysis patients with secondary hyperparathyroidism. Data on laboratory measurements and drug prescriptions were collected every 3 months. Main exposures were frequencies of measuring serum calcium and phosphorus [weekly/biweekly/monthly (reference)] and serum parathyroid hormone (PTH) [monthly/bimonthly/trimonthly (reference)] levels. Outcomes were achievement of guideline-specified ranges of mineral metabolism markers when serum levels were over, and maintenance of ranges when levels were already within, respective specified ranges, use of intravenous vitamin D receptor activator (VDRA) and initiation of cinacalcet use. Associations were examined via generalized estimating equations. Results: When serum marker levels exceeded the target range, weekly measurement of calcium and phosphorus was positively associated with achievement of the guideline-specified calcium range [adjusted odds ratio (AOR): 1.57, 95% confidence interval (CI) 1.09-2.26] but not phosphorus range (AOR: 0.99, 95% CI 0.74-1.33). Monthly measurement of PTH was positively associated with achievement of the guideline-specified PTH range (AOR: 1.14, 95% CI 1.01-1.27). When serum marker levels were within the guideline-specified range, increased frequency of measurements was not associated with in-range maintenance of marker levels for any of the three mineral markers assessed. Regarding treatment regimen, relatively frequent measurement of serum calcium and phosphorus was positively associated with cinacalcet initiation and relatively frequent measurement of serum PTH with cinacalcet initiation and intravenous VDRA use. Conclusions: Our results suggest that increasing frequency of measurements is helpful when serum marker levels exceed the target range, partially via adjustment in the therapeutic regimen. We found no evidence that frequent measurements are helpful when mineral levels are already within target ranges.

Development and Validation of a Disease-Specific Instrument to Measure Diet-Targeted Quality of Life for Postoperative Patients with Esophagogastric Cancer.

BACKGROUND: Patients who have undergone esophagectomy or gastrectomy have certain dietary limitations because of changes to the alimentary tract. This study attempted to develop a psychometric scale, named "Esophago-Gastric surgery and Quality of Dietary life (EGQ-D)," for assessment of impact of upper gastrointestinal surgery on diet-targeted quality of life. METHODS: Using qualitative methods, the study team interviewed both patients and surgeons involved in esophagogastric cancer surgery, and we prepared an item pool and a draft scale. To evaluate the scale's psychometric reliability and validity, a survey involving a large number of patients was conducted. Items for the final scale were selected by factor analysis and item response theory. Cronbach's alpha was used for assessment of reliability, and correlations with the short form (SF)-12, esophagus and stomach surgery symptom scale (ES(4)), and nutritional indicators were analyzed to assess the criterion-related validity. RESULTS: Through multifaceted discussion and the pilot study, a draft questionnaire comprising 14 items was prepared, and a total of 316 patients were enrolled. On the basis of factor analysis and item response theory, six items were excluded, and the remaining eight items demonstrated strong unidimensionality for the final scale. Cronbach's alpha was 0.895. There were significant associations with all the subscale scores for SF-12, ES(4), and nutritional indicators. CONCLUSIONS: The EGQ-D scale has good contents and psychometric validity and can be used to evaluate disease-specific instrument to measure diet-targeted quality of life for postoperative patients with esophagogastric cancer.

Association between hand-grip strength and depressive symptoms: Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS).

BACKGROUND: no study has examined the longitudinal association between hand-grip strength and mental health, such as depressive symptoms. OBJECTIVE: we investigated the relationship between baseline hand-grip strength and the risk of depressive symptoms. DESIGN: a prospective cohort study. SETTING AND SUBJECTS: a prospective cohort study with a 1-year follow-up was conducted using 4,314 subjects from community-dwelling individuals aged 40-79 years in two Japanese municipalities, based on the Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS, 2008-10). METHODS: we assessed baseline hand-grip strength standardised using national representative data classified by age and gender, and depressive symptoms at baseline and after the follow-up using the five-item version of the Mental Health Inventory (MHI-5). RESULTS: the 4,314 subjects had a mean age of 66.3 years, 58.5% were women, and mean unadjusted hand-grip strength was 29.8 kg. Multivariable random-effect logistic regression analysis revealed that subjects with lower hand-grip strength (per 1SD decrease) had higher odds of having depressive symptoms at baseline [adjusted odds ratio (AOR) 1.15, 95% confidence interval (CI) 1.06-1.24; P = 0.001]. Further, lower hand-grip strength (per 1SD decrease) was associated with the longitudinal development of depressive symptoms after 1 year (AOR 1.13, 95% CI 1.01-1.27; P = 0.036). CONCLUSIONS: using a large population-based sample, our results suggest that lower hand-grip strength, standardised using age and gender, is both cross-sectionally and longitudinally associated with depressive symptoms.

Abnormal mineral metabolism and mortality in hemodialysis patients with secondary hyperparathyroidism: evidence from marginal structural models used to adjust for time-dependent confounding.

BACKGROUND: Hemodialysis patients with mineral and bone disorders (MBDs) have an abnormally high relative risk of death, but their absolute risk of death is unknown. Further, previous studies have not accounted for possible time-dependent confounding of the association between MBD markers and death due to the effect of markers of MBD on treatments, which subsequently may affect MBD markers. STUDY DESIGN: Multicenter, 3-year, prospective, case-cohort study. SETTING & PARTICIPANTS: 8,229 hemodialysis patients with secondary hyperparathyroidism (parathyroid hormone level ≥180 pg/mL and/or receiving vitamin D receptor activators) at 86 facilities in Japan. PREDICTORS: Serum phosphorus, calcium, and parathyroid hormone levels. OUTCOME: All-cause mortality. MEASUREMENTS: Marginal structural models were used to compute absolute differences in all-cause mortality associated with different levels of predictors while accounting for time-dependent confounding. RESULTS: The association between phosphorus level and mortality appeared U-shaped, although only higher phosphorus level categories reached statistical significance: compared to those with phosphorus levels of 5.0-5.9 mg/dL (1.61-1.93 mmol/L), patients with the highest (≥9.0 mg/dL [≥2.90 mmol/L]) phosphorus levels had 9.4 excess deaths/100 person-years (rate ratio, 2.79 [95% CI, 1.26-6.15]), whereas no association was found for the lowest phosphorus category (<3.0 mg/dL [<0.97 mmol/L]; rate ratio, 1.54 [95% CI, 0.87-2.71]). Similarly, hypercalcemia (≥10.0 mg/dL [≥2.50 mmol/L]) was associated with excess deaths, and the highest level of hypercalcemia (≥11.0 mg/dL [≥2.75 mmol/L]) was associated with 5.8 excess deaths/100 person-years (rate ratio, 2.38 [95% CI, 1.77-3.21]) compared to those with levels of 9.0-9.4 mg/dL (2.25-2.37 mmol/L). Abnormally high parathyroid hormone levels were not associated with excess deaths. LIMITATIONS: Possible residual confounding. CONCLUSIONS: These results reinforce the idea that serum calcium (in addition to phosphorus) level is an important predictor of the absolute risk of death in hemodialysis patients with secondary hyperparathyroidism.

Association of serum bicarbonate with bone fractures in hemodialysis patients: the mineral and bone disorder outcomes study for Japanese CKD stage 5D patients (MBD-5D).

BACKGROUND/AIMS: Bone fracture is often complicated in hemodialysis (HD) patients. Metabolic acidosis is related to bone disease and muscle wasting, but it is not known whether acid-base disturbance is associated with the risk of bone fractures. The aim of this study was to clarify the association of serum bicarbonate level with bone fracture in HD patients. METHODS: Using a subcohort of the Mineral and Bone Disorder Outcomes Study for Japanese CKD Stage 5D Patients (MBD-5D), 890 prevalent HD patients (age: 62 years old, male: 62.8%, duration of dialysis: 8.3 years) with secondary hyperparathyroidism were studied. After measuring predialysis serum bicarbonate at a 2-day interdialytic interval, we prospectively followed them every 3 months, and examined the occurrence of any type of bone fracture or hospitalization due to fracture over a 3-year observation period. RESULTS: Seventy-four bone fractures and 47 hospitalizations due to fracture were observed during the follow-up period. HD patients with serum bicarbonate <20 mmol/l had a 1.93 (95% CI 1.01-3.71)-fold higher risk for all-cause fractures than those with serum bicarbonate of 20.0-21.9 mmol/l. A higher bicarbonate level (≥22 mmol/l) was also related to an increased risk of bone fracture. A restricted cubic regression spline disclosed that the higher or the lower than 21.0 mmol/l of serum bicarbonate, the greater the risk for bone fracture. CONCLUSION: Both a lower level and a higher level of predialysis bicarbonate concentration were associated with risk of bone fracture in HD patients with secondary hyperparathyroidism.

Association between kyphosis and subacromial impingement syndrome: LOHAS study.

BACKGROUND: Kyphosis is a cause of scapular dyskinesis, which can induce various shoulder disorders, including subacromial impingement syndrome (SIS). This study aimed to clarify the impact of kyphosis on SIS with use of cross-sectional data from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS). METHODS: The study enrolled 2144 participants who were older than 40 years and participated in health checkups in 2010. Kyphosis was assessed by the wall-occiput test (WOT) for thoracic kyphosis and the rib-pelvic distance test (RPDT) for lumbar kyphosis. The associations between kyphosis, SIS, and reduction in shoulder elevation (RSE) were investigated. RESULTS: Age- and gender-adjusted logistic regression analysis demonstrated significant association between SIS and WOT (odds ratio, 1.65; 95% confidence interval, 1.02, 2.64; P < .05), whereas there was no significant association between SIS and RPDT. Multivariable logistic regression analysis demonstrated no significant association between SIS and both WOT and RPDT, whereas there was significant association between SIS and RSE. CONCLUSION: RSE plays a key role in the development of SIS, and thoracic kyphosis might influence the development of SIS indirectly by reducing shoulder elevation induced by the restriction of the thoracic spine extension and scapular dyskinesis.

Development of a Culinary Intervention (Cooking Class) for Salt Reduction in Japanese Home Cooking: Strategies and Assessment.

Introduction: Culinary interventions (cooking classes) are a potential educational tool for salt reduction in the home diet, but their content has never been reported in detail. This study aimed to develop a cooking class for salt reduction, describe its rationale and structure so that other parties could replicate it, and preliminarily assess its impact on salt intake. Methods: A multidisciplinary research team developed a cooking class package to reduce salt content in the Japanese home diet. The package comprised its developmental policy, teaching methodology, a menu and recipes, and an implementation manual and aimed to allow third parties to replicate and modify the content. The team took the following step-by-step developmental approach. First, traditional home meals were modeled to create strategies contributing to a target of 2 g salt/meal. Then, educational topics were developed through these strategies, and finally, a dietitian produced menus and prepared documents for the class. The impact of the cooking class was assessed in a nonrandomized study of community residents. The outcome was differences in urinary salt excretion before and after the intervention. General linear models were used to account for the possible confounders. Results: The authors assumed 4-7 g salt/meal from analyzing typical Japanese home diets and developed 3 strategies: (1) restricting salt content in the main dish, (2) maintaining good tastes without salty dishes, and (3) balancing nutrition with low-salt dishes. On the basis of these strategies, the authors selected a total of 5 educational topics that participants could learn and apply at home: 1a, a simple and reliable technique to limit salt in a serving; 2a, excluding salty dishes; 2b, staple foods with notable flavor and aroma; 3a, flavoring without salt in side dishes; and 3b, ingredients that should be used intentionally. The team dietitian translated these educational topics into a menu and recipes for hands-on training and prepared a manual for conducting the class. The class developed using this approach was successfully overseen by a dietitian outside the research team. In the validation study, the intervention group (n=52) showed a greater decrease in urinary salt excretion than the control group (n=46), with an adjusted difference of -1.38 g (p=0.001). Conclusions: The authors developed a cooking class package for salt reduction so that third parties could replicate and modify the class. The significant salt reduction noted in this study warrants further studies to apply this cooking class to other populations.

Prevalence of lumbar spinal stenosis, using the diagnostic support tool, and correlated factors in Japan: a population-based study.

BACKGROUND: Few studies have examined the prevalence of lumbar spinal stenosis (LSS) in the general population. The purposes of this study were to estimate the prevalence of LSS and to investigate correlated factors for LSS in Japan. METHODS: A questionnaire survey was performed on 4,400 subjects selected from residents aged 40-79 years in Japan by stratified two-stage random sampling in 2010. The question items consisted of lower-limb symptoms suggestive of LSS, the diagnostic support tool for LSS (LSS-DST), demographic and lifestyle characteristics, comorbidities, the Japanese Perceived Stress Scale (JPSS), and the Mental Health Index 5 (MHI-5). Using the LSS-DST, the presence of LSS was predicted to estimate the prevalence of LSS. Logistic regression analysis was performed to examine the relationship between LSS and correlated factors. RESULTS: Questionnaires were obtained from 2,666 subjects (60.6 %), consisting of 1,264 males (47.4 %). The mean (standard deviation) age was 60.0 (10.9) years. According to the LSS-DST, 153 subjects were regarded as having LSS. The prevalence was estimated to be 5.7 %. When standardizing this value with the age distribution of the Japanese population, it was estimated that 3,650,000 Japanese subjects aged 40-79 years might have LSS using the LSS-DST. Prevalence increased with age and was particularly high in subjects aged 70-79 years, irrespective of gender. As correlated factors, an advanced age (60 years or older), diabetes mellitus, urological disorders, and osteoarthritis/fracture as comorbidities, and depressive symptoms, were associated with LSS. CONCLUSIONS: This study elucidated the prevalence of LSS and factors associated with LSS in Japan. This is the first report describing the estimated prevalence of LSS and associated factors using a strictly sampled representative population.

Infectious Risk and Variability of Hemoglobin Level in Patients Undergoing Hemodialysis.

Introduction: In the management of anemia in chronic kidney disease, hemoglobin levels often fall below or exceed target ranges. Past retrospective cohort studies of patients undergoing hemodialysis with conventional erythropoiesis stimulating agents (ESAs) found that hemoglobin level fluctuations predicted mortality and cardiovascular adverse events; long-acting agents were thereafter widely available. An updated validation by a prospective cohort study was needed. Methods: Using Cox regression models, we evaluated associations between hemoglobin variability and all-cause death, hospitalization, and cardiovascular, thrombotic, or infectious adverse event outcomes in 3063 hemodialysis patients' data from the Japanese Dialysis Outcomes and Practice Patterns Study (J-DOPPS) from 2012 to 2018. Results: During a median follow-up time of 2.5 years, all-cause mortality was lowest in the first quartile and tended to be higher in groups with greater hemoglobin variability (hazard ratio [HR]: 95% confidence interval for the fourth quartile of an absolute value of hemoglobin variability: 1.44 [0.99-2.08], P for trend = 0.056). Infectious event incidence in these patients was also lower in the first quartile than for the other quartiles (P for trend < 0.01). The association was more pronounced in patients with lower serum ferritin levels or iron supplementation. Cardiovascular and thrombotic event incidence was not associated with hemoglobin variability. Conclusions: Maintenance hemodialysis patients on ESA treatment with higher hemoglobin variability are at higher risk for all-cause mortality and particularly infectious events.

Effects of iron-based phosphate binders on mortality and cardiovascular events in patients receiving maintenance dialysis.

Phosphate binders are the main treatment for hyperphosphatemia in patients with chronic kidney disease, and iron-based phosphate binders have been used with increasing frequency in recent years. This study examined the association of the use of iron-based, rather than non-iron-based, phosphate binders with the incidence of cardiovascular events, in a real-world setting. We used data from a cohort comprising representative adult patients on maintenance hemodialysis in Japan. The exposure of interest was the time-varying use of phosphate binders, classified into "iron-based", "only non-iron-based", and "no use". The primary outcome was a composite of cardiovascular events and all-cause deaths. A marginal structural Cox regression model was used to deal with possible time-dependent confounding. Of the 2247 patients from 58 hemodialysis facilities, iron-based and only non-iron-based phosphate binders were used in 328 (15%) and 1360 (61%), respectively, at baseline. Hazard ratios (95% confidence intervals) for iron-based and non-iron-based phosphate binders versus no use of phosphate binders were 0.35 (0.24, 0.52) and 0.44 (0.33, 0.58), respectively. The hazard ratio for iron-based relative to non-iron-based phosphate binders was 0.81 (0.58, 1.13), which was not statistically significant. Further studies are warranted to elucidate whether the use of iron-based phosphate binders reduces the event rate.

α-Blocker Use in Hemodialysis: The Japan Dialysis Outcomes and Practice Patterns Study.

Rationale & Objective: Despite α-blockers' use for hypertension as add-on therapy in patients treated with hemodialysis, scant information is available on their association, particularly with safety, in these patients. Study Design: Prospective cohort study. Setting & Participants: patients treated with hemodialysis and receiving antihypertensive agents in the Japan Dialysis Outcomes and Practice Patterns Study, phases 4-6, were analyzed. Exposure: Primary exposure was the prescription of α-blocking antihypertensive agents at baseline. Outcomes: Incident fractures, falls, and all-cause mortality. Analytical Approach: Multivariable Cox and modified Poisson regression analysis. Results: Of 5,149 patients treated with hemodialysis (mean age, 65 years; 68% men) receiving antihypertensive drugs, 717 (14%) received α-blocking agents. During a mean follow-up period of 2.0 years, 247 fractures, 525 falls, and 498 deaths occurred. Multivariable analysis showed no significant association of α-blocker use and increased risk of fractures (hazard ratio [HR], 0.92 [95% confidence interval {CI}, 0.61-1.38]), falls (HR, 0.94 [95% CI, 0.74-1.20]), or all-cause deaths (HR, 0.87 [95% CI, 0.64-1.20]) compared with α-blocker nonuse. α-Blocker use was, however, significantly associated with a decreased risk of all-cause mortality in the subgroup analysis, for example, patients who were older (HR, 0.71 [95% CI, 0.51-0.99]), were women (HR, 0.68 [95% CI, 0.48-0.95]), or reported a history of cardiovascular disease (HR, 0.67 [95% CI, 0.48-0.95]) or a predialysis blood pressure of ≥140 mm Hg (HR, 0.69 [95% CI, 0.49-0.98]). Limitations: Selection bias cannot be ruled out given the prevalent user analysis. Conclusions: No significant association between α-blocker use and the risk of worse safety-related outcomes was seen, indicating that clinicians may safely prescribe α-blockers to patients receiving hemodialysis who require blood pressure lowering. Plain-Language Summary: α-Blockers have been generally reserved for use as add-on therapy for resistant or refractory hypertension. However, little is known about the safety of α-blockers in patients treated by hemodialysis. We analyzed 5,149 patients receiving hemodialysis in Japan who were receiving antihypertensive drugs from the Japan Dialysis Outcomes and Practice Patterns Study. The results showed no significant increase in the risk of fractures, falls, or deaths for patients using α-blockers compared with those who did not, suggesting that α-blockers may be safely prescribed for patients receiving hemodialysis who need to lower their blood pressure.

Impact of treatment of hyperkalaemia on quality of life: design of a prospective observational cohort study of long-term management of hyperkalaemia in patients with chronic kidney disease or chronic heart failure in Japan.

INTRODUCTION: Hyperkalaemia (HK) is a frequent complication in patients with chronic kidney disease (CKD) and/or chronic heart failure (CHF). HK must be managed, both to protect patients from its direct clinical adverse outcomes and to enable treatment with disease-modifying therapies including renin-angiotensin-aldosterone system inhibitors. However, the experiences of patients undergoing treatment of HK are not clearly understood. Optimising treatment decisions and improving long-term patient management requires a better understanding of patients' quality of life (QOL). Thus, the aims of this research are: (1) to describe treatment patterns and the impact of treatment on a patient's QOL, (2) to study the relationships between treatment patterns and the impact of treatment on a patient's QOL and (3) to study the relationships between the control of serum potassium (S-K) and the impact of treatment on a patient's QOL, in patients with HK. METHODS AND ANALYSIS: This is a prospective cohort study with 6 months of follow-up in 30-40 outpatient nephrology and cardiology clinics in Japan. The participants will be 350 patients with CKD or CHF who received their first potassium binders (PB) prescription to treat HK within the previous 6 months. Medical records will be used to obtain information on S-K, on treatment of HK with PBs and with diet, and on the patients' characteristics. To assess the impact of treatment on a patient's QOL, questionnaires will be used to obtain generic health-related QOL, CKD-specific and CHF-specific QOL, and PB-specific QOL. Multivariable regression models will be used to quantify how treatment patterns and S-K control are related to the impact of treatment on a patient's QOL. ETHICS AND DISSEMINATION: Institutional review boards at all participating facilities review the study protocol. Patient consent will be obtained. The results will be published in international journals. TRIAL REGISTRATION NUMBER: NCT05297409.

Validation of a new instrument for measuring disease-specific quality of life: A pilot study among patients with chronic kidney disease and hyperkalemia.

BACKGROUND: To prepare for a longitudinal study of the effects of potassium-lowering treatment on quality of life (QOL), we quantified the validity of a new disease-specific instrument for measuring QOL, using data from patients who had hyperkalemia (HK) due to chronic kidney disease (CKD) or chronic heart failure, and were also being treated with potassium binders (PBs). METHODS: In this cross-sectional study, the participants were 98 patients at five outpatient clinics in Japan. The outcome measures were the Medical Outcomes Study 36-item short-form (SF-36), a widely used generic measure of QOL, and the Quality of Life Disease-specific Impact Scale (QDIS-7), a recently-developed disease-specific measure of QOL. Internal-consistency reliability was quantified, and factor analysis was done to confirm hypothesized QOL dimensions. Validation tests used two external criteria: CKD stage, and PB formulation. PB formulation was used because different formulations are associated with different degrees of patients' burden. Using a previously-described method, we computed the relative validity (RV) of the two measures. RESULTS: Two factor scoring of the SF-36 and one factor scoring of the QDIS-7, as standardized from previous studies, were confirmed. The RVs showed that the QDIS-7 was much more valid than the SF-36, for discriminating between groups defined clinically (by CKD stage), and also between groups defined by PB formulation. Reliability was satisfactory: 0.73-0.95 for the SF-36 and 0.86 for the QDIS-7. CONCLUSIONS: The QDIS-7 with CKD or PB attributions was more valid than the SF-36 for measuring the effects of CKD and of PB formulation on QOL.

Locomotor dysfunction and risk of cardiovascular disease, quality of life, and medical costs: design of the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS) and baseline characteristics of the study population.

BACKGROUND: There is little evidence regarding long-term outcomes of locomotor dysfunction such as cardiovascular events, quality of life, and death. We are conducting a prospective cohort study to evaluate risk of cardiovascular disease, quality of life, medical costs, and mortality attributable to locomotor dysfunction. The present study determined baseline characteristics of participants in the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS). METHODS: Cohort participants were recruited from residents between 40 and 80 years old who received regular health check-ups conducted by local government each year between 2008 and 2010 in Minami-Aizu Town and Tadami Town in Fukushima Prefecture, Japan. Musculoskeletal examination included assessment of physical examination of the cervical and lumbar spine, and upper and lower extremities and of physical function, such as grasping power, one-leg standing time, and time for the 3-m timed up-and-go test. Cardiovascular risk factors, including blood pressure and biological parameters, were measured at annual health check-ups. We also conducted a self-administered questionnaire survey. RESULTS: LOHAS participants comprised 1,289 men (mean age 65.7 years) and 1,954 women (mean age 66.2 years) at the first year. The proportion of obese individuals (body mass index 25.0 kg/m(2)) was 31.9% in men and 34.3% in women, and 41.0% of participants reported being followed up for hypertension, 7.0% for diabetes, and 43.6% for hypercholesterolemia. Prevalence of lumbar spinal stenosis was 10.7% in men and 12.9% in women, while prevalence of low back pain was 15.8% in men and 17.6% in women. CONCLUSION: The LOHAS is a novel population-based prospective cohort study that will provide an opportunity to estimate the risk of cardiovascular disease, quality of life, medical costs, and mortality attributable to locomotor dysfunction, and to provide the epidemiological information required to develop policies for detection of locomotor dysfunction.

Cohort profile: Alliance for Quality Assessment in Healthcare-Dialysis (AQuAH-D) prospective cohort study of patients on haemodialysis in Japan.

PURPOSE: The global burden of kidney failure is increasing, but the treatment of kidney failure varies widely between patients, between dialysis facilities and over time. The Alliance for Quality Assessment in Healthcare-Dialysis (AQuAH-D) aims to conduct efficient and timely cohort studies on associations between those variations and clinical and patient-reported outcomes. PARTICIPANTS: Included are outpatients aged 20 years old or older who are undergoing haemodialysis and have consented to participate. A total of 2895 patients were enrolled from 25 facilities in Japan between August 2018 and July 2020 and are to be followed until 31 December 2026. Chart review and annual questionnaires are used to collect data on patient characteristics and on outcomes including quality of life. Data on medications, haemodialysis prescriptions and blood tests are obtained from existing electronic records. Data are collected retrospectively from 1 January 2017 to patient enrolment, and prospectively from patient enrolment until the end of December 2026. FINDINGS TO DATE: To date, the mean age is 68.3 (SD 12.2) years and 35.2% are female. The most common cause of kidney failure is diabetic nephropathy (37.4%). In January 2020, the facilities' median weekly doses of erythropoietin stimulating agent (ESA) and of intravenous vitamin D ranged from 1846 to 9692 IU (epoetin alfa equivalent) and 0.78 to 2.25 µg (calcitriol equivalent), respectively. The facilities' percentages of patients to whom calcimimetics are prescribed varied from 19% to 79%. During the retrospective period (averaging 1.85 years per participant), the incidence rates of any hospitalisation and of hospitalisation due to cardiovascular disease were 67.2 and 12.0 per 100 person-years, respectively. FUTURE PLANS: AQuAH-D data will be updated every 6 months and will be available for studies addressing a wide range of research questions, using the advantages of granular data and quality-of-life measurement of ageing patients on haemodialysis.