Skipping Breakfast and Progression of Chronic Kidney Disease in the General Japanese Population: the Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease (ISSA-CKD).

INTRODUCTION: Breakfast-skipping habits are associated with adverse health outcomes including coronary heart disease, metabolic syndrome and diabetes mellitus. However, it remains uncertain whether skipping breakfast affects chronic kidney disease (CKD) risk. This study aimed to examine the association between skipping breakfast and progression of CKD. METHODS: We retrospectively conducted a population-based cohort study using the data from the Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease (ISSA-CKD). Between 2008 and 2019, we included 922 participants aged 30 years or older who had CKD (estimated glomerular filtration rate <60 mL/min/1.73m2 and/or proteinuria) at baseline. Breakfast-skippers were defined as participants who skipped breakfast more than 3 times per week. The outcome was CKD progression defined as a decline of at least 30% in the eGFR from the baseline status. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for CKD progression, adjusted for other CKD risk factors. RESULTS: During a follow-up period with a mean of 5.5 years, CKD progression occurred in 60 (6.5%) participants. The incidence rate (per 1,000 person-years) of CKD progression was 21.5 in the breakfast-skipping group and 10.7 in the breakfast-eating group (p=0.029), respectively. The multivariable-adjusted HR (95% CI) for CKD progression was 2.60 (95% CI 1.29‒5.26) for the breakfast-skipping group (p=0.028) compared with the group eating breakfast. There were no clear differences in the association of skipping breakfast with CKD progression in subgroup analyses by sex, age, obesity, hypertension, diabetes mellitus, baseline eGFR and baseline proteinuria. CONCLUSION: Skipping breakfast was significantly associated with higher risk of CKD progression in the general Japanese population.

Associations between the Serum Triglyceride Level and Kidney Outcome in Patients with Chronic Kidney Disease: The Fukuoka Kidney disease Registry Study.

AIMS: Hypertriglyceridemia is a risk factor for chronic kidney disease (CKD). However, whether or not it predicts the risk of CKD progression is unknown. This study evaluated the association between serum triglyceride (TG) levels and kidney disease progression in patients with non-dialysis-dependent CKD. METHODS: The Fukuoka Kidney disease Registry (FKR) study was a multicenter, prospective longitudinal cohort study. In total, 4,100 patients with CKD were followed up for 5 years. The primary outcome was the incidence of CKD progression, defined as a ≥ 1.5-fold increase in serum creatinine level or the development of end-stage kidney disease. The patients were divided into quartiles according to baseline serum TG levels under non-fasting conditions: Q1 ＜87 mg/dL; Q2, 87-120 mg/dL; Q3, 121-170 mg/dL, and Q4 ＞170 mg/dL. RESULTS: During the 5-year observation period, 1,410 patients met the criteria for CKD progression. The multivariable-adjusted Cox proportional hazards model showed a significant association between high serum TG level and the risk of CKD progression in the model without macroalbuminuria as a covariate (multivariable hazard ratio[HR] for Q4 versus Q1, 1.20; 95% CI, 1.03-1.41; P=0.022), but the significance disappeared after adjusting for macroalbuminuria (HR for Q4 versus Q1, 1.06; 95% CI, 0.90-1.24; P=0.507). CONCLUSIONS: The present findings suggest that individuals with high serum TG levels are more likely to develop CKD progression than those without; however, whether or not higher serum TG levels reflect elevated macroalbuminuria or lead to CKD progression via elevated macroalbuminuria is unclear.

History of fragility fracture is associated with cardiovascular mortality in hemodialysis patients: the Q-Cohort study.

INTRODUCTION: In patients undergoing dialysis, major bone fracture is associated with a high risk of mortality, including death of cardiovascular (CV) origin. In the present study, we aimed to determine whether a history of fragility fracture is a predictor of CV death in patients undergoing hemodialysis with long-term follow-up. MATERIALS AND METHODS: In total, 3499 patients undergoing hemodialysis were analyzed for 10 years. We evaluated the history of fragility fracture in each patient at enrollment. The primary outcome was CV death. A Cox proportional hazard model and a competing risk approach were applied to determine the association between a history of fragility fracture and CV death. RESULTS: A total of 346 patients had a history of fragility fracture at enrollment. During a median follow-up of 8.8 years, 1730 (49.4%) patients died. Among them, 621 patients experienced CV death. Multivariable Cox analyses after adjustment for confounding variables showed that a history of fragility fracture was associated with CV death (hazard ratio, 1.47; 95% confidence interval, 1.16-1.85). In the Fine-Gray regression model, a history of fragility fracture was an independent risk factor for CV death (subdistribution hazard ratio, 1.36; 95% confidence interval, 1.07-1.72). CONCLUSION: In a large cohort of patients undergoing hemodialysis, a history of fragility fracture was an independent predictor of CV death.

Relationships of Weight Change from 20 Years of Age with the Risks of All-Cause and Cardiovascular Mortality in Patients with Chronic Kidney Disease.

AIMS: Weight changes from a young age are known to be associated with poor life outcomes in the general population. However, little is known about the association between weight change from a young age and life expectancy in patients with chronic kidney disease (CKD). METHODS: Data of 2,806 nondialysis CKD patients who participated in the Fukuoka Kidney Disease Registry (FKR) Study, a multicenter observational study, were analyzed. The primary outcome was all-cause death, whereas the secondary outcome was cardiovascular mortality. The covariate of interest was weight change, defined as the difference between body weight at study enrollment and at 20 years old. Cox proportional-hazards models were used to estimate the risks of mortality for participants with weight changes of ≥ 5 or ＜5 kg compared with those with stable weights. RESULTS: During the 5-year observation period, 243 participants died from all causes and 62 from cardiovascular disease. The risk of all-cause mortality in the weight-loss group was significantly higher than that in the stable-weight group (multivariable-adjusted hazard ratio, 2.11; 95% confidence interval [CI], 1.52-2.93). Conversely, the risk of cardiovascular mortality in the weight-loss group was significantly higher than that in the stable-weight group (multivariable-adjusted hazard ratio, 2.48; 95% CI, 1.32-4.64). However, no significant association was observed between weight gain and the risks of all-cause and cardiovascular mortalities. CONCLUSION: Weight loss from 20 years of age was found to be associated with higher risks of all-cause and cardiovascular mortalities in patients with CKD.

Dysbiosis of Gut Microbiota in Patients with Chronic Kidney Disease.

Objective The gut bacterial microbiota is altered in patients with chronic kidney disease (CKD). However, the bacterial composition at each stage of CKD is unclear in these patients, including those receiving renal replacement therapy. We herein report the changes in the gut microbiota among patients with CKD. Methods A total of 93 individuals were recruited for the study. Seventy-three patients had stage 3-5 CKD, including those receiving renal replacement therapy (CKD group), and 20 were age- and sex-matched controls (CKD stage 1-2). The gut microbiome composition was analyzed using a 16S ribosomal RNA gene-based sequencing protocol. Results At the genus level, the butyrate-producing bacteria Lachnospira, Blautia, Coprococcus, Anaerostipes, and Roseburia were more abundant in the control group (linear discriminant analysis score of >3) than in the CKD group. Lachnospira was more abundant in the control group than in patients with CKD stage 3a. Compared to the control group, multiplex butyrate-producing bacteria were deficient in patients with CKD stage 3b-5D, including in patients receiving renal replacement therapy. Conclusion Our findings highlight the fact that the gut bacterial composition, including butyrate-producing bacteria, deteriorates from CKD stage 3b. Even after renal replacement therapy, the bacterial composition did not change.

Impact of Electrocardiographic Parameters on Sudden Death in Patients Receiving Maintenance Hemodialysis: Ten-Year Outcomes of the Q-Cohort Study.

AIM: Sudden death is one of the most common causes of death among hemodialysis patients. Electrocardiography (ECG) is a noninvasive and inexpensive test that is regularly performed in hemodialysis clinics. However, the association between abnormal ECG findings and the risk of sudden death in hemodialysis patients is yet to be fully elucidated. Thus, the aim of this study was to determine the ECG parameters linked to sudden death in patients undergoing hemodialysis. METHODS: The Q-Cohort Study is a multicenter, longitudinal, observational study of hemodialysis patients. In this study, 1,153 Japanese hemodialysis patients aged ≥ 18 years with ECG data recorded within 1 year of study enrollment were followed up for 10 years. Cox proportional hazards models were used to estimate the multivariate-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the association between ECG parameters and sudden death. RESULTS: During the median follow-up period of 9.0 years, 517 patients died, 76 of whom exhibited sudden death. After adjusting for confounding factors, higher heart rate, QT prolongation, and left ventricular hypertrophy as per the Sokolow-Lyon voltage criteria were found to be independently associated with an increased risk of sudden death. The adjusted HRs [95% CIs] for each abnormal ECG parameter were 2.02 [1.05-3.89], 2.10 [1.30-1.77], and 1.91 [1.18-3.09], respectively. CONCLUSIONS: Higher heart rate, QT prolongation, and left ventricular hypertrophy on ECG have been determined to be associated with an increased risk of sudden death. Therefore, regular ECG recording could enable medical practitioners to identify hemodialysis patients who require intervention to prevent lethal arrhythmia.

Association between Serum C-Reactive Protein Concentrations and Risk of Cancer-Related Mortality in Patients Undergoing Hemodialysis: 10-Year Outcomes of the Q-Cohort Study.

INTRODUCTION: Cancer constitutes a major source of morbidity and mortality among people undergoing hemodialysis (HD). A systemic inflammatory response is associated with the incidence and prognosis of cancer in the general population. However, the effect of systemic inflammation on cancer-related mortality in patients undergoing HD remains unclear. METHODS: We analyzed 3,139 patients registered in the Q-Cohort Study, which is a multicenter, observational cohort study of patients on hemodialysis in Japan. The primary outcome was cancer-related mortality during a 10-year follow-up. The covariate of interest was serum C-reactive protein (CRP) concentrations at baseline. The patients were divided into tertiles based on their serum CRP concentrations at baseline (tertile [T] 1: ≤0.07; T2: 0.08-0.24; and T3: ≥0.25). The association between serum CRP concentrations and cancer-related mortality was calculated using the Cox proportional hazards model and the Fine-Gray subdistribution hazards model with non-cancer-related death as a competing risk. RESULTS: During the 10-year follow-up, 216 patients died of cancer. In the multivariable analysis, the risk of cancer-related mortality in the highest tertile (T3) of serum CRP concentrations was significantly higher than that in the lowest tertile (T1) (multivariable-adjusted hazard ratio [95% confidence interval]: 1.68 [1.15-2.44]). This association remained consistent in the competing risk model, in which the subdistribution hazard ratio was 1.47 and the 95% confidence interval was 1.00-2.14 for T3 compared with T1. CONCLUSION: Higher serum CRP concentrations are associated with an increased risk of cancer-related mortality in patients undergoing maintenance HD.

Casual Serum Triglyceride Concentrations and New-Onset Chronic Kidney Disease in the General Japanese Population: The Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease Study.

INTRODUCTION: Non-fasting triglyceride (TG) concentrations are useful for predicting various diseases, but most epidemiological studies investigated the association between fasting TG concentrations and chronic kidney disease (CKD). This study aimed to examine the association between casual (fasting or non-fasting) serum TG concentrations and new-onset CKD in the general Japanese population. METHODS: We conducted a population-based, retrospective cohort study using annual health checkup data of residents of Iki City, Nagasaki Prefecture, Japan. Between 2008 and 2019, participants without CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2 and/or proteinuria) at baseline were included. Casual serum TG concentrations were classified by sex as tertile 1 (men: <0.95 mmol/L; women: <0.86 mmol/L), tertile 2 (0.95-1.49 mmol/L; 0.86-1.25 mmol/L), and tertile 3 (≥1.50 mmol/L; ≥1.26 mmol/L). The outcome was incident CKD. Multivariable-adjusted hazard ratios and 95% confidence intervals were estimated using the Cox proportional hazards model. RESULTS: 4,946 participants (2,236 [45%] men and 2,710 [55%] women; 3,666 [74%] fasting and 1,182 [24%] non-fasting) were included in the present analysis. During an average follow-up of 5.2 years, 934 participants (434 men and 509 women) developed CKD. In men, the incidence rate (per 1,000 person-years) of CKD increased with an elevation in TG concentrations (tertile 1: 29.4, tertile 2: 42.2, and tertile 3: 43.3). This association was significant, even after adjustment for other risk factors of age, current smoking habits, current alcohol intake, exercise habits, obesity, hypertension, diabetes mellitus, hyper-low-density-lipoprotein cholesterolemia, and use of lipid-lowering therapy (p = 0.003 for trend). In contrast, in women, TG concentrations were not associated with incident CKD (p = 0.547 for trend). CONCLUSION: Casual serum TG concentrations are significantly associated with new-onset CKD in Japanese men in the general population.

Cardiovascular Risk Factor Burden and Treatment Control in Patients with Chronic Kidney Disease: A Cross-Sectional Study.

AIM: Cardiovascular disease is a life-threatening chronic kidney disease (CKD) complication. Although cardiovascular risk factor management is significant in patients with CKD, there are few reports that detail the frequency of complications and the treatment of cardiovascular risk factors at different stages of CKD in clinical practice. METHODS: There were a total of 3,407 patients with non-dialysis-dependent CKD who participated in the Fukuoka Kidney disease Registry Study, and they were cross-sectionally analyzed. The patients were classified into five groups based on their estimated glomerular filtration rate and urinary albumin to creatinine ratio according to Kidney Disease: Improving Global Outcomes 2012 guidelines, which recommend low, moderate, high, very high, and extremely high risk groups. The primary outcomes were the cardiovascular risk factor burden and the treatment status of cardiovascular risk factors. Using a logistic regression model, the association between the CKD groups and the treatment status of each risk factor was examined. RESULTS: The proportion of patients with hypertension, diabetes mellitus, and dyslipidemia significantly increased as CKD progressed, whereas the proportion of patients who achieved cardiovascular risk factor treatment targets significantly decreased. In the multivariable analysis, the odds ratios (ORs) of uncontrolled treatment targets were significantly higher for hypertension (OR 3.68) in the extremely high risk group than in the low risk group. CONCLUSIONS: Patients with non-dialysis-dependent CKD demonstrate an increased cardiovascular risk factor burden with greater severity of CKD. Extremely high risk CKD is associated with difficulty in managing hypertension.

Association between prevalence of laxative use and history of bone fractures and cardiovascular diseases in patients with chronic kidney disease: the Fukuoka Kidney disease Registry (FKR) study.

BACKGROUND: Constipation is a common complication in patients with chronic kidney disease (CKD) and is involved in the pathogenesis of dysbiosis and progression of CKD. However, little is known about its association with disorders of the bone-cardiovascular axis in patients with CKD. METHODS: We performed a cross-sectional analysis of 3878 patients with CKD using the baseline dataset of the Fukuoka Kidney disease Registry study, as a multicenter, prospective cohort study of pre-dialysis CKD patients. The main exposure of interest was constipation defined as use of at least one type of laxative. The main outcomes were the histories of bone fractures and cardiovascular diseases (CVDs) as manifestations of disorders of the bone-cardiovascular axis. RESULTS: The prevalences of laxative use and histories of bone fractures and CVDs increased as kidney function declined. Among the 3878 patients, 532 (13.7%) patients used laxatives, 235 (6.1%) patients had prior bone fractures, and 1001 (25.8%) patients had prior CVDs. Histories of bone fractures and CVDs were significantly more prevalent among laxative users (P < 0.05). Multivariable-adjusted logistic regression analysis revealed that patients with laxatives had a significantly higher odds ratios for histories of bone fractures and CVDs than those without laxatives [adjusted odds ratios (95% confidence intervals) 1.67 (1.20-2.31) and 1.70 (1.30-2.22), respectively, P < 0.05]. CONCLUSIONS: These results suggest that constipation indicated by laxative use is associated with increased prevalences of historical bone fractures and CVDs in pre-dialysis patients with CKD.

Current antihypertensive treatment and treatment-resistant hypertension in Japanese patients with chronic kidney disease.

BACKGROUND: Hypertension is an important prognostic predictor in patients with chronic kidney disease (CKD), and the recommended target blood pressure has been continuously revised. This study aimed to reveal the current antihypertensive practices in Japanese patients with CKD. METHODS: In the Fukuoka Kidney disease Registry, we extracted 3664 non-dialysis-dependent patients with CKD. Apparent treatment-resistant hypertension (aTRH) was defined as a failure of blood-pressure control treated with three antihypertensive medication classes or a treatment with ≥ 4 classes regardless of blood pressure. The blood-pressure control complied with the target blood pressure recommended by the KDIGO 2012 guideline. RESULTS: The median age of the patients was 67 years, body mass index (BMI) was 23 kg/m2, and estimated glomerular filtration rate (eGFR) was 40 mL/min/1.73 m2. The number of patients with unachieved blood-pressure control was 1933, of whom 26% received ≥ 3 classes of antihypertensive medications. The first choice of medication was renin-angiotensin system inhibitors, followed by calcium-channel blockers. The rate of thiazide use was low in all CKD stages (3-11%). The prevalence of aTRH was 16%, which was significantly associated with BMI (odds ratio [95% confidence interval] per 1-standard deviation change, 1.38 [1.25-1.53]), decreased eGFR (1.87 [1.57-2.23]), as well as age, diabetes mellitus, and chronic heart disease. CONCLUSIONS: Renal dysfunction and obesity are important risk factors of aTRH. Even under nephrologist care, most patients were treated with insufficient antihypertensive medications. It is important to prescribe sufficient classes of antihypertensive medications, including diuretics, and to improve patients' lifestyle habits.

Serum alkaline phosphatase and infection-related mortality in hemodialysis patients: ten-year outcomes of the Q-cohort study.

BACKGROUND: High serum alkaline phosphatase (ALP) levels are associated with excess all-cause and cardiovascular mortality in patients undergoing hemodialysis (HD). However, the long-term relationship between serum ALP levels and infection-related mortality remains unclear. METHODS: A total of 3502 maintenance HD patients were registered in the Q-Cohort Study, an observational cohort study in Japan. The primary outcome was infection-related mortality during a 10-year follow-up period. The covariate of interest was serum ALP levels at baseline. The association between serum ALP levels and infection-related mortality was calculated using a Cox proportional hazards model and a Fine-Gray subdistribution hazards model with non-infection-related death as a competing risk. RESULTS: During the follow-up period, 446 patients died of infection. According to their baseline serum ALP levels, the patients were categorized into sex-specific quartiles (Q1-Q4). Compared with patients in the lowest serum ALP quartile (Q1), those in the highest quartile (Q4) had a significantly higher multivariable-adjusted hazard ratio (HR) of 1.70 [95% confidence interval (CI) 1.24-2.32] for infection-related mortality. Furthermore, the HR for every 50 U/L increase in serum ALP levels was 1.24 (95% CI 1.12-1.36) for infection-related mortality. These associations remained consistent in the competing risk model: subdistribution HR, 1.47; 95% CI 1.07-2.03 for Q4 compared with Q1. CONCLUSION: Higher serum ALP levels were significantly associated with a higher risk of infection-related mortality in patients undergoing HD.

Sex differences in the 10-year survival of patients undergoing maintenance hemodialysis in the Q-Cohort Study.

Women have a longer life expectancy than men in the general population. However, it has remained unclear whether this advantage is maintained in patients undergoing maintenance hemodialysis. The aim of this study was to compare the risk of mortality, especially infection-related mortality, between male and female hemodialysis patients. A total of 3065 Japanese hemodialysis patients aged ≥ 18 years old were followed up for 10 years. The primary outcomes were all-cause and infection-related mortality. The associations between sex and these outcomes were examined using Cox proportional hazards models. During the median follow-up of 8.8 years, 1498 patients died of any cause, 387 of whom died of infection. Compared with men, the multivariable-adjusted hazard ratios (95% confidence interval) for all-cause and infection-related mortality in women were 0.51 (0.45-0.58, P < 0.05) and 0.36 (0.27-0.47, P < 0.05), respectively. These findings remained significant even when propensity score-matching or inverse probability of treatment weighting adjustment methods were employed. Furthermore, even when the non-infection-related mortality was considered a competing risk, the infection-related mortality rate in women was still significantly lower than that in men. Regarding all-cause and infection-related deaths, women have a survival advantage compared with men among Japanese patients undergoing maintenance hemodialysis.

Association between Multimorbidity and Kidney Function among Patients with Non-Dialysis-Dependent CKD: The Fukuoka Kidney Disease Registry Study.

AIM: Individuals with chronic kidney disease (CKD) have a high prevalence of comorbidities, including cardiovascular disease (CVD) and its risk factors. However, epidemiological results to assess the association between multimorbidity and kidney function among the CKD population remains limited. METHODS: We performed a cross-sectional analysis of the association between 23 comorbid conditions and reduced kidney function in 4,476 patients with non-dialysis-dependent CKD enrolled in a multicenter cohort in Japan. Reduced kidney function was defined as an estimated glomerular filtration rate of ≤ 60 mL/min/1.73 m2. RESULTS: The mean age of patients was 67 years (male, 56.0%). The prevalence of hypertension, diabetes mellitus, dyslipidemia, prior CVD, cancer, and bone fracture, which are the major comorbidities, was 83.3%, 28.7%, 45.9%, 23.3%, 12.7%, and 6.3%, respectively. Multivariable-adjusted analyses revealed that age, male sex, hypertension, dyslipidemia, prior CVD, body mass index, urinary protein excretion, and underlying kidney disease were independent factors associated with reduced kidney function. Importantly, the odds ratios (ORs) for reduced kidney function increased linearly as the number of major comorbid conditions increased (OR for 1-2 conditions: 2.22, 95% confidence interval [CI]: 1.65-2.97; OR for 3-4 conditions: 3.04, 95% CI: 2.12-4.37; OR for ≥ 5 conditions: 4.37, 95% CI: 1.75-10.9). The upward trend in OR was more pronounced with cardiovascular comorbidities but not significant with non-cardiovascular comorbidities. CONCLUSIONS: In conclusion, we observed an independent association between cardiovascular comorbidity and its risk factors and reduced kidney function. The results of this study highlight the importance of managing multimorbidity among patients with CKD.

Serum Alkaline Phosphatase Levels and Increased Risk of Brain Hemorrhage in Hemodialysis Patients: The Q-Cohort Study.

AIM: Elevated serum alkaline phosphatase (ALP) levels have been associated with increased risks of all-cause and cardiovascular mortality in patients receiving hemodialysis. However, little is known about the impact of serum ALP levels on the development of stroke, such as brain hemorrhage and infarction. METHODS: A total of 3,497 patients receiving maintenance hemodialysis registered in the multicenter observational Q-Cohort Study were analyzed. The primary outcomes were the incidences of brain hemorrhage and infarction. The covariate of interest was serum ALP levels. Patients were divided into tertiles based on their serum ALP levels (U/L) at baseline (T1, ＜69.3; T2, 69.3-98.4; T3, ＞98.4). The risks of brain hemorrhage, brain infarction, and composite stroke were estimated using Cox proportional hazards models and competing risk models with all-cause death as a competing risk. RESULTS: A total of 89 patients developed brain hemorrhage and 195 patients developed brain infarction during the 4-year follow-up period. The risk of brain hemorrhage in the highest tertile (T3) was significantly higher than that in the lowest tertile (T1) (multivariable-adjusted hazard ratio [95% confidence interval], 1.93 [1.12-3.35], subdistribution hazard ratio, 1.91 [1.10-3.30]). However, there was no significant association between serum ALP levels and the risk of brain infarction or composite stroke. CONCLUSIONS: Higher serum ALP levels are associated with an increased risk of brain hemorrhage, but not brain infarction, in patients receiving maintenance hemodialysis. High serum ALP level is thus an important risk factor for brain hemorrhage in hemodialysis patients.

Association of the nutritional risk index for Japanese hemodialysis patients with long-term mortality: The Q-Cohort Study.

BACKGROUND: Protein-energy wasting (PEW) is a risk factor for mortality in patients undergoing hemodialysis. Recently, a nutritional risk index for Japanese hemodialysis patients (NRI-JH) has been proposed as a surrogate index of PEW. However, no study has determined the association of the NRI-JH with long-term mortality in patients undergoing hemodialysis. Furthermore, the validity of the NRI-JH has not been confirmed. METHODS: In total, 3046 patients undergoing hemodialysis and registered in the Q-Cohort Study were followed up for 10 years. The NRI-JH was calculated on the basis of body mass index and serum levels of albumin, total cholesterol, and creatinine. The patients were divided into four groups according to the NRI-JH scores: 0-3 (G1, n = 1343), 4-7 (G2, n = 1136), 8-10 (G3, n = 321), and 11-13 (G4, n = 246). We examined the association between the NRI-JH and the 4-year and 10-year risks of all-cause, cardiovascular, and infection-related deaths using the Cox proportional hazards model. RESULTS: During the follow-up period, 647 patients died during the first 4 years, and 1503 patients died within 10 years. The 4-year prognosis was analyzed and compared with the lowest NRI-JH score group. Multivariable-adjusted hazard ratios (95% confidence intervals) for all-cause death were 1.93 (1.57-2.38), 2.68 (2.05-3.50), and 3.16 (2.40-4.16) in the G2, G3, and G4 groups, respectively. Similarly, a higher NRI-JH score was associated with an increased risk of cardiovascular and infection-related deaths. CONCLUSION: A higher NRI-JH score was associated with an increased risk of long-term mortality in patients undergoing maintenance hemodialysis. TRIAL REGISTRATION: The study protocol was registered in the University Hospital Medical Information Network (UMIN) clinical trial registry (UMIN ID: 000000556).

Causes of death in patients undergoing maintenance hemodialysis in Japan: 10-year outcomes of the Q-Cohort Study.

BACKGROUND: Although the mortality rate in patients on hemodialysis remains extremely high, detailed information on causes of death over long-term periods is limited. The aim of this study was to clarify the underlying causes of death in patients undergoing maintenance hemodialysis in Japan. METHODS: This was a 10-year, multicenter, observational study of 3528 outpatients undergoing maintenance hemodialysis in Japan. Clinical outcomes were analyzed and causes of death were classified into six broad categories including cardiovascular diseases, infectious diseases, malignant neoplasms, cachexia, trauma/accidents, and other diseases, and more detailed subcategories. RESULTS: During the 10-year follow-up period, 1748 (49.5%) patients died. The most frequent causes of death were cardiovascular diseases (36.1%), followed by infectious diseases (25.8%) and malignant neoplasms (13.5%). In a detailed classification, sudden death, pulmonary infection, and lung cancer were the most common causes of death in cardiovascular diseases, infectious diseases, and malignant neoplasms, respectively. CONCLUSION: Our study determined details on causes of death in Japanese hemodialysis patients during the 10-year follow-up period. Cardiovascular disease, especially sudden death is noticeable cause of death among patients on hemodialysis.

Associations Between Surrogates of Skeletal Muscle Mass and History of Bone Fracture in Patients with Chronic Kidney Disease: The Fukuoka Kidney disease Registry (FKR) Study.

Patients with chronic kidney disease (CKD) are at increased risks of both sarcopenia and fragility fractures. However, information on the association between skeletal muscle mass (SMM) and the risk of bone fractures in patients with CKD is lacking. We performed a cross-sectional analysis of 4146 patients with CKD using the baseline dataset of the Fukuoka Kidney disease Registry Study, as a multicenter, prospective cohort study of pre-dialysis CKD patients. The main measure was estimated SMM (eSMM) calculated using an equation validated by bioelectrical impedance analysis with two independent datasets of 100 and 81 CKD patients. The main outcome was historical bone fractures. The associations between sex-specific quartiles (Q1-Q4) of eSMM and fracture history were assessed by logistic regression analyses. The prevalence of a history of fractures increased and eSMM decreased with progressive CKD stages. Among the 4146 patients, 249 had prior bone fractures, including 111 patients in Q1 (lowest quartile), 65 in Q2, 46 in Q3, and 27 in Q4 (highest quartile). A multivariable-adjusted model revealed that patients in Q1 had a significantly higher odds ratio (95% confidence interval) for bone fracture history than those in Q4 (reference): Q1, 2.77 (1.32-5.80); Q2, 1.95 (1.05-3.65); and Q3, 1.57 (0.90-2.75) (P-value for trend < 0.001). Similar associations were obtained when other skeletal muscle surrogates were applied: serum creatinine to serum cystatin C and daily urinary creatinine excretion. These results suggest that a lower eSMM is associated with an increased prevalence of historical bone fractures in pre-dialysis CKD patients.

Association between geriatric nutritional risk index and stroke risk in hemodialysis patients: 10-Years outcome of the Q-Cohort study.

BACKGROUNDS AND AIMS: The geriatric nutritional risk index (GNRI), which is calculated using the serum albumin level and body mass index, is a nutritional marker associated with an increased risk of cardiovascular events in patients who are receiving hemodialysis. However, no studies have examined the association between the GNRI level and the incidence of stroke in this population. METHODS: Three thousand forty-five patients were registered in the Q-Cohort Study, which is a multicenter, observational cohort of hemodialysis patients. The main outcomes were brain infarction and brain hemorrhage. The main exposure was GNRI levels at baseline. Patients were divided into quartiles on the basis of baseline GNRI levels: Q1, <90.7; Q2, 90.7-95.5; Q3, 95.6-99.8; Q4, >99.8. The risk of brain infarction or hemorrhage was estimated using the multivariable-adjusted Cox proportional hazard risk models and restricted cubic spline analyses. RESULTS: During the 10-year follow-up period, 326 patients developed brain infarction and 149 patients developed brain hemorrhage. Cox proportional hazard risk models showed that the risk of brain infarction and hemorrhage in Q1 was significantly higher than that in Q4 group. The hazard ratios [95% confidence intervals] were 1.49 [1.05-2.12] and 1.89 [1.11-3.20], respectively. Restricted cubic spline curves showed that a lower GNRI was incrementally associated with an increased risk for both brain infarction and brain hemorrhage. CONCLUSIONS: Our results suggest that a lower GNRI is an independent risk factor for both brain infarction and hemorrhage in patients who are receiving maintenance hemodialysis.

Association of hyperphosphatemia with an increased risk of sudden death in patients on hemodialysis: Ten-year outcomes of the Q-Cohort Study.

BACKGROUND AND AIMS: Sudden death is one of the most common causes of death among patients on hemodialysis. Although hyperphosphatemia is a well-known risk factor for cardiovascular and all-cause deaths, the studies focusing on the relationship between serum phosphate levels and the risk of sudden death are limited. This study aimed to clarify the relationship between serum phosphate levels and the risk of sudden death in patients on hemodialysis. METHODS: This is a multicenter, longitudinal, and observational study. A total of 3505 patients, registered in the Q-Cohort Study, who underwent maintenance hemodialysis, and were followed up for 10 years, were included. Patients were divided into quartiles on the basis of baseline serum phosphate levels: Q1 (n = 886), <4.2 mg/dL; Q2 (n = 837), 4.2-4.8 mg/dL; Q3 (n = 908), 4.9-5.6 mg/dL; and Q4 (n = 874), ≥5.7 mg/dL. Associations between baseline serum phosphate levels and sudden death were analyzed using the Cox proportional hazards model and the Fine-Gray regression model. RESULTS: During the follow-up period, 227 patients died from sudden death. The risk for sudden death was significantly higher in the highest quartile (Q4) than in the lowest quartile (Q1) as the reference group (multivariable-adjusted hazard ratios and 95% confidence intervals: Q1, 1.00; Q2, 1.15 [0.77-1.70], Q3, 1.31 [0.89-1.93], and Q4, 1.72 [1.14-2.59]; hazard ratio for every 1-mg/dL increase in the serum phosphate level, 1.23 [1.09-1.39]; p < 0.001). CONCLUSIONS: Hyperphosphatemia is independently associated with an elevated risk of sudden death in patients on hemodialysis.