Journal of Renal Nutrition最新文献

Objective: This large cohort study aimed to examine the overall associations of physical activity (PA) and estimated cardiorespiratory fitness (eCRF) with incident chronic kidney disease (CKD).

Methods: This study included a total of 274,292 participants (mean age, 37.9±8.0 years; 41% women) using data collected from the Kangbuk Samsung Health Study. The participants were categorized into three groups: PA (Inactive, Insufficiently active, and Active) and eCRF(Low, Middle, High). Furthermore, subgroup analyses were conducted to examine the differences in the risks of CKD incidence by age and sex. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results: A total of 932 participants (0.34%) developed CKD. Physical activity level was not associated with CKD risk in the overall cohort. However, younger participants (<45 years) showed lower CKD risks, with hazard ratios (HRs) of 0.53 (95% CI: 0.36-0.79) and 0.73 (95% CI: 0.53-1.00) for insufficiently active and active individuals, respectively. Similarly, men exhibited reduced CKD risks, with HRs of 0.77 (95% CI: 0.59-1.00) and 0.81 (95% CI: 0.66-1.00) in these groups. Additionally, those in the high eCRF group had a 20% reduced CKD risk (HR, 0.80; 95% CI: 0.67-0.96) compared to the low eCRF group.

Conclusions: The associations between PA or eCRF and incident CKD showed differences according to age and sex.

Objective: Recent studies have reported the prognostic implications of the discordance between creatinine-based and cystatin C-based estimated glomerular filtration rates (eGFR_cr and eGFR_cys, respectively); however, the associations of protein intake with the eGFR discordance have not been investigated. The present study investigated whether protein intake was associated with the discordance between eGFR_cr and eGFR_cys.

Design and methods: We cross-sectionally analyzed data from a Japanese community-based cohort including 6,143 participants (50.7% women; age range, 40-97 years). Protein intake was estimated by food groups derived from a validated food frequency questionnaire. As a measure of discordance, we modeled the ratio of eGFR_cys and eGFR_cr (eGFR_cys divided by eGFR_cr) continuously in multivariable linear regression models and categorically (<0.8, 0.8-1.1, and ≥1.2) in multinomial logistic regression models. We analyzed men and women separately given their distinct dietary patterns.

Results: The mean eGFR ratio was 1.15 in men and 1.19 in women. In multivariable linear regression analysis, total protein was positively associated with the eGFR ratio in men (regression coefficient, 0.005 [95% CI, 0.003, 0.007]). When animal and plant proteins were analyzed separately, a significant positive association was seen for animal protein only in men (0.005 [0.003, 0.007]). The results were similar when we modeled protein intake categorically by multinomial logistic regression.

Conclusion: This study suggests intake of dietary protein, especially animal protein in men, as a determinant of eGFR discordance. Future studies exploring eGFR discordance and health outcomes should consider simultaneously assessing dietary protein intake.

Background: Low serum parathyroid hormone (PTH) is an accepted marker for adynamic bone disease which is characterized by increased morbidity and mortality in maintenance hemodialysis (MHD) patients. In light of the known cross-sectional associations between PTH and malnutrition-inflammation syndrome, we aimed to examine the longitudinal associations between PTH with changes in nutritional and inflammatory parameters and clinical outcomes in MHD patients with low PTH.

Methods: This historical prospective and longitudinal study analyzed a clinical database at a single hemodialysis center, containing the medical records of 459 MHD patients (mean age of 71.4 ± 12.9 years old, 171 women), treated between the years 2007-2020. Bone turnover, nutritional and inflammatory marker levels were recorded at 0, 6, 12, 18, 24, 30, and 36 months followed by a median of 24 additional months of clinical observations. According to previous use of vitamin D analogs and/or calcium-sensing receptor agonists, the study participants were divided into treatment-related and disease-related groups. A linear mixed effects model was adjusted for baseline demographics and clinical parameters.

Results: Of 459 MHD patients, 81 (17.6%) had PTH lower than 150pg/mL. Among them, 30 patients had treatment-related and 51 had disease-related low PTH. At baseline, MHD patients with treatment-related low PTH had a higher rate of diabetes compared to the disease-related group. In a linear mixed effects model, increased PTH over time was associated with decreased levels of alkaline phosphatase and C-reactive protein and with increased hemoglobin and albumin, but not the geriatric nutritional risk index at 3-year follow-up. The survival rate did not differ between the groups, with the risk of hospitalizations due to fractures being higher (HR: 4.04 with 95% CI: 1.51-10.8) in the disease-related group. Statistical significance of this association was abolished after adding C-reactive protein or alkaline phosphatase to the multivariate models.

Conclusions: Low serum PTH in MHD patients behaves differently depending on its cause, with a higher risk of fractures in the disease-related group. This association is dependent on inflammation. Our results should be verified in larger epidemiological studies.

Because of increased risks of cardiovascular disease and death, patients with hyperphosphatemia receiving maintenance dialysis are advised to limit phosphorus consumption and are prescribed phosphate binders in an effort to better control serum phosphate concentrations. Because of large pill size, pill burden, and tolerability issues, phosphate binder adherence is relatively poor. On ingestion, phosphate is absorbed from the intestine via transcellular or paracellular transport. Data show that inhibiting sodium-hydrogen exchanger 3 modulates paracellular phosphate absorption (the predominant pathway in humans). Tenapanor is a first-in-class, minimally absorbed, phosphate absorption inhibitor that selectively inhibits sodium-hydrogen exchanger 3, with a mechanism distinct from, and complementary to, that of phosphate binders. In phase 3 and postregistrational studies, tenapanor conferred statistically significant and clinically meaningful reductions in serum phosphate in patients receiving maintenance dialysis with hyperphosphatemia. Here, we review the available preclinical and clinical data on the effects of tenapanor on controlling intestinal phosphate absorption.

Objectives: The association between high-density lipoprotein (HDL) cholesterol levels and mortality in elderly patients undergoing hemodialysis is not well established. Thus, this study investigated HDL levels and mortality in elderly Korean patients undergoing hemodialysis.

Methods: We recruited 1860 incident hemodialysis patients aged greater than 70 years from a retrospective cohort of the Korean Society of Geriatric Nephrology. The primary outcome measure was all-cause mortality.

Results: The mean age of the cohort was 77.8 years, and 1049 (56.4%) were men. When we grouped the patients into HDL cholesterol tertiles, the T1 group (HDL level <30 mg/dL in men and <33 mg/dL in women) had a higher proportion of patients with end-stage kidney disease due to diabetic nephropathy. During the median follow-up period of 3.1 years, 1109 (59.7%) deaths occurred. In a multivariable Cox regression model, the T1 group had a significantly higher risk of mortality (hazard ratio [HR], 1.28; 95% confidence interval, 1.10-1.50; P = .002) compared to the T3 group. A nonlinear analysis using a restrictive spline curve showed that low HDL cholesterol levels were associated with increased HR when HDL cholesterol levels were <40 mg/dL; however, there was no association between HDL cholesterol and mortality when HDL cholesterol levels were >40 mg/dL. Triglyceride/HDL ratio was not significantly associated with the risk of mortality (HR per 1 log increase, 1.08; 95% confidence interval, 0.99-1.18; P = .069).

Conclusions: Low HDL cholesterol levels are associated with an increased risk of mortality in elderly patients undergoing hemodialysis. However, there was no significant relationship between HDL cholesterol levels and mortality when levels were below 40 mg/dL. Therefore, low HDL cholesterol levels may be a useful risk factor for predicting mortality in elderly patients undergoing hemodialysis.

Objective: Dietary sodium restriction is important in the prognosis of patients with chronic kidney disease (CKD). The association between saltiness perception and sodium intake among CKD patients is unclear, and the factors that influence saltiness are also not fully understood. We evaluated saltiness perception in CKD patients employing a cost-effective saltiness perception test using sodium solutions and evaluated the association between saltiness perception, sodium intake, and the influencing factors.

Design and methods: CKD outpatients not undergoing dialysis were enrolled from two medical centers and underwent saltiness perception tests together with 24-hour urine collections to measure daily sodium intake. Participants who perceived saltiness using the test solution containing 25 mM sodium were regarded to have "preserved" saltiness perception, while those unable to perceive saltiness were regarded as having "impaired" saltiness perception.

Results: Of the total 132 participants, the median daily sodium intake was 3.36 g (range; 0.51-9.95 g/day), and 43 (32.6%) were ex- or current smokers. When participants were divided into 3 groups (G) according to daily sodium intake level: low (G1; 0.51-2.61 g/day), middle (G2; 2.62-3.99 g/day), and high (G3; 4.06-9.95 g/day), there was an obvious difference in impaired saltiness perception between three groups: 6.8% in G1, 50.0% in G2 and 86.4% in G3 (P value = 8.035 × 10^-14, Cochran-Armitage test). In a multiple regression analysis in which the saltiness perception was adopted as a subjective variable, smoking habit (ex- or current smoker) and nonadherence to dietary sodium restriction were identified as significant explanatory variables.

Conclusion: We revealed the clear relationship between higher daily sodium intake and impaired saltiness perception that is related to nonadherence to dietary sodium restriction and smoking habit, both of which could be intervened by nutritional counseling and public health education.

Objectives: Chronic kidney disease (CKD) significantly contributes to the socio-economic burden both in China and worldwide. Previous research has shown that experiencing childhood famine is linked to various chronic conditions like diabetes, hypertension, and proteinuria. However, the long-term effects of early-life famine exposure on adult kidney function remain unclear. This study investigates whether exposure to the Chinese Great Famine (1959-1962) is associated with a decline in glomerular filtration rate (GFR) later in life.

Design and methods: China Health and Retirement Longitudinal Study is a population-based observational study. We analyzed data from 8,828 participants in the 2011-2012 baseline survey, updated in 2014. Participants were categorized based on their birth year into fetal-exposed (1959-1962), childhood-exposed (1949-1958), adolescence/adult-exposed (1912-1948), and nonexposed (1963-1989) groups. The estimated GFR (eGFR) was calculated using the CKD-EPI-Cr-Cys equation (2021), with CKD defined as an eGFR below 60 mL/min/1.73 m².

Results: Average eGFR values were 103.0, 96.8, 91.2, and 76.3 mL/min/1.73 m² for the fetal-exposed, childhood-exposed, adolescence/adult-exposed, and nonexposed groups, respectively. The eGFR in the exposed groups was significantly lower compared to the nonexposed group. Specifically, famine exposure correlated with a lower eGFR (coefficient estimates [CE] -9.14, 95% confidence interval [CI] -9.46, -8.82), with the strongest association observed in the adolescence/adult-exposed group (CE -26.74, 95% CI -27.75, -25.74). Adjusting for variables such as demographics, physical and laboratory tests, complications, and personal habits like smoking and drinking did not qualitatively alter this association (CE -1.38, 95% CI -1.72, -1.04). Further stratification by sex, body mass index, alcohol consumption history, hypertension, diabetes, Center for Epidemiologic Studies Depression score, and education level showed that the association remained consistent.

Conclusions: Exposure to famine during different life stages can have enduring effects on GFR decline in humans.

Objective: Malnutrition is highly prevalent in patients with kidney failure. Since body weight does not reflect body composition, other methods are needed to determine muscle mass, often estimated by fat-free mass (FFM). Bioimpedance spectroscopy (BIS) is frequently used for monitoring body composition in patients with kidney failure. Unfortunately, BIS-derived lean tissue mass (LTM_BIS) is not suitable for comparison with FFM cutoff values for the diagnosis of malnutrition, or for calculating dietary protein requirements. Hypothetically, FFM could be derived from BIS (FFM_BIS). This study aims to compare FFM_BIS and LTM_BIS with computed tomography (CT) derived FFM (FFM_CT). Secondarily, we aimed to explore the impact of different methods on calculated protein requirements.

Methods: CT scans of 60 patients with kidney failure stages 4-5 were analyzed at the L3 level for muscle cross-sectional area, which was converted to FFM_CT. Spearman rank correlation coefficient and 95% limits of agreement were calculated to compare FFM_BIS and LTM_BIS with FFM_CT. Protein requirements were determined based on FFM_CT, FFM_BIS, and adjusted body weight. Deviations over 10% were considered clinically relevant.

Results: FFM_CT correlated most strongly with FFM_BIS (r = 0.78, P < .001), in males (r = 0.72, P < .001) and in females (r = 0.60, P < .001). A mean difference of -0.54 kg was found between FFM_BIS and FFM_CT (limits of agreement: -14.88 to 13.7 kg, P = .544). Between LTM_BIS and FFM_CT a mean difference of -12.2 kg was apparent (limits of agreement: -28.7 to 4.2 kg, P < .001). Using FFM_CT as a reference, FFM_BIS best predicted protein requirements. The mean difference between protein requirements according to FFM_BIS and FFM_CT was -0.7 ± 9.9 g in males and -0.9 ± 10.9 g in females.

Conclusion: FFM_BIS correlates well with FFM_CT at a group level, but shows large variation within individuals. As expected, large clinically relevant differences were observed in calculated protein requirements.