Weight loss has an additive effect on the proteinuria reduction of angiotensin II receptor blockers in hypertensive patients with chronic kidney disease

BACKGROUND: Weight reduction is a lifestyle intervention that has been introduced for prevention and management of chronic kidney disease (CKD). We investigate the additive anti-proteinuric effect of weight reduction on the usage of angiotensin II receptor blockers (ARBs) and its potential mechanisms in hypertensive CKD patients. METHODS: This study is a subanalysis of data from an open-label, randomized, controlled clinical trial. Among the 235 participants, 227 were assigned to subgroups according to changes in body weight. RESULTS: Fifty-eight participants (25.6%) were assigned to group 1 (≥1.5% decrease in body weight after 16 weeks), 32 participants (14.1%) were assigned to group 2 (1.5–0.1% decrease in body weight), and 136 participants (59.9%) were assigned to group 3 (≥ 0.0% increase in body weight). Characteristics at enrollment were not different among the three groups, but mean differences in weight and percent changes in urinary sodium excretion over the period were statistically different (P < 0.001 and P = 0.017). Over the study period, unintentional weight loss independently increased the probability of reduced albuminuria (group 1, relative risk 6.234, 95% confidence interval 1.913–20.315, P = 0.002). Among urinary cytokines, only podocalyxin level decreased significantly in participants who lost weight (P = 0.013). CONCLUSION: We observed that weight loss had an additive effect on the anti-proteinuric effects of ARBs in nondiabetic hypertensive CKD patients, although it was minimal. An additive effect was shown in both obese and non-obese participants, and its possible mechanism is related to reduction of podocyte damage.

Estimating the urinary sodium excretion in patients with chronic kidney disease is not useful in monitoring the effects of a low-salt diet

BACKGROUND: Several epidemiologic studies have suggested that the urine sodium excretion (USE) can be estimated in lieu of performing 24-hour urine collection. However, this method has not been verified in patients with chronic kidney disease (CKD) or in an interventional study. The purpose of this study was to evaluate the usefulness of estimating USE in a prospective low-salt diet education cohort (ESPECIAL). METHODS: A new formula was developed on the basis of morning fasting urine samples from 228 CKD patients in the ESPECIAL cohort. This formula was compared to the previous four formulas in the prediction of 24-hour USE after treatment with olmesartan and low-salt diet education. RESULTS: Most previously reported formulas had low predictability of the measured USE based on the ESPECIAL cohort. Only the Tanaka formula showed a small but significant bias (9.8 mEq/day, P < 0.05) with a low correlation (r = 0.34). In contrast, a new formula showed improved bias (−0.1 mEq/day) and correlation (r = 0.569) at baseline. This formula demonstrated no significant bias (−1.2 mEq/day) with the same correlation (r = 0.571) after 8 weeks of treatment with olmesartan. Intensive low-salt diet education elicited a significant decrease in the measured USE. However, none of the formulas predicted this change in the measured urine sodium after diet adjustment. CONCLUSION: We developed a more reliable formula for estimating the USE in CKD patients. Although estimating USE is applicable in an interventional study, it may be unsuitable for estimating the change of individual sodium intake in a low-salt intervention study.

Predialysis hyponatremia and mortality in elderly patients beginning to undergo hemodialysis

BACKGROUND/AIMS: Predialysis hyponatremia has been recently reported to be associated with mortality in incident hemodialysis patients. However, whether hyponatremia is associated with unfavorable outcomes in elderly patients remains unknown. We hypothesized that nephrology referral inf luences hyponatremia, and aimed to define how nephrology referral affects the association between hyponatremia and mortality in the elderly. METHODS: We retrospectively assessed mortality in 599 incident hemodialysis patients aged ≥ 70 at a tertiary university hospital, between 2000 and 2010. We analyzed 90-day and 1-year all-cause mortality (ACM) in relation to predialysis serum sodium (sNa). We divided the patients into two groups according to predialysis glucose-corrected sNa: hyponatremia (< 135 mmol/L) and normonatremia (135 to 145 mmol/L). RESULTS: Low estimated glomerular filtration rate, high phosphorus, low albumin, nonpreparation of arteriovenous fistula or graft, and late referral were associated with a low sNa in the elderly. Among 599 patients, 106 and 174 patients died at the 90-day and 1-year follow-ups, respectively. Each 10-mmol/L increase in predialysis sNa tended to be associated with lower 90-day and 1-year ACM. When patients were stratified by nephrology referral, hyponatremia was associated with increased mortality in early referral group (90-day ACM: hazard ratio [HR] = 2.335, p = 0.041; 1-year ACM: HR = 1.790, p = 0.024). However, hyponatremia was not associated with mortality in late referral group. CONCLUSIONS: Predialysis hyponatremia at hemodialysis initiation is associated with late referra

Cutaneous vasculitis and renal involvement in Mycoplasma pneumoniae infection

No abstract available.

Not Salt Taste Perception but Self-Reported Salt Eating Habit Predicts Actual Salt Intake

Excessive dietary salt intake is related to cardiovascular morbidity and mortality. Although dietary salt restriction is essential, it is difficult to achieve because of salt palatability. However, the association between salt perception or salt eating habit and actual salt intake remains uncertain. In this study, we recruited 74 healthy young individuals. We investigated their salt-eating habits by questionnaire and salt taste threshold through a rating scale that used serial dilution of a sodium chloride solution. Predicted 24-hr urinary salt excretions using Kawasaki's and Tanaka's equations estimated dietary salt intake. Participants' mean age was 35 yr, and 59.5% were male. Salt sense threshold did not show any relationship with actual salt intake and a salt-eating habit. However, those eating "salty" foods showed higher blood pressure (P for trend=0.048) and higher body mass index (BMI; P for trend=0.043). Moreover, a salty eating habit was a significant predictor for actual salt intake (regression coefficient [beta] for Kawasaki's equation 1.35, 95% confidence interval [CI] 10-2.69, P=0.048; beta for Tanaka's equation 0.66, 95% CI 0.01-1.31, P=0.047). In conclusion, a self-reported salt-eating habit, not salt taste threshold predicts actual salt intake.

Estimating 24-Hour Urine Sodium Level with Spot Urine Sodium and Creatinine

The 24-hr urine sodium excretion level was estimated based on the spot urine sodium, and the efficacy of the formula was validated to determine the status of low salt intake or =100 mEq/day using the estimated amount> or =100 mEq/day was 84.3%, 87.6%, and 84.8%, respectively. In conclusion, the three equations used to estimate the 24-hr urine sodium content were useful to determine the status of low salt intake.

A Higher Salt Intake Leads to a Lower Rate of Adequate Blood Pressure Control

The relationship between salt intake and adequate blood pressure control is not well investigated in Korea populations, especially in patients with cardiovascular disease. This cross-sectional study enrolled 19,083 subjects who participated in the Korea National Health and Nutrition Examination Survey conducted from 2009-2011. The amount of salt intake was estimated using the Tanaka equations based on spot urine samples. Comparing patients with and without cardiovascular disease, systolic blood pressure (129.1+/-18.1 mmHg vs. 120.0+/-18.1 mmHg, P<0.001) and the amount of urinary sodium excretion (149.4+/-37.5 mM/day vs. 144.1+/-36.2 mM/day, P<0.001) were higher in patients with cardiovascular diseases. Among patients with cardiovascular disease, the high blood pressure group showed an increased amount of urinary sodium excretion compared to the normal blood pressure group (155.5+/-38.2 vs. 146.6+/-36.9 mM/day, P<0.001). The odds ratio (OR) of high blood pressure was higher (OR, 1.825; 95% CI, 1.187-2.807; P-for-trend 0.003, highest quartile of urinary sodium excretion vs. lowest quartile) in patients with cardiovascular disease. A higher amount of urinary sodium excretion was associated with a lower rate of adequate blood pressure control in Korean population, especially with cardiovascular disease.

Estimated 24-Hour Urine Sodium Excretion Is Correlated with Blood Pressure in Korean Population: 2009-2011 Korean National Health and Nutritional Examination Survey

No large-scale studies have investigated the association between salt intake and hypertension in Korean population. To investigate the relationship of blood pressure to salt consumption, we analyzed data from 19,476 participants in the 2009-2011 Korean National Health and Nutritional Examination Survey (KNHANES). Urinary sodium excretion over 24-hr (24HUNa) was estimated from spot urine tests using Tanaka's equation. The study subjects were stratified into hypertensive and normotensive groups. Hypertensive participants (n=6,552, 33.6%) had higher estimated 24HUNa, 150.4+/-38.8 mEq/day, than normotensive participants, 140.5+/-34.6 mEq/day (P<0.001). The association between 24HUNa and blood pressure outcomes was not affected by adjustment for other risk factors for hypertension (odds ratio 0.001; 95% confidence interval 0.001-0.003; P<0.001). Increases in 24HUNa of 100 mEq/day were associated with a 6.1+/-0.3/2.9+/-0.2 mmHg increase in systolic/diastolic blood pressure in all participants. This effect was stronger in hypertensive participants (increase of 8.1+/-0.5/3.4+/-0.3 mmHg per 100 mEq/day) and smaller in normotensive participants (2.9+/-0.3/1.3+/-0.2 mmHg). These results support recommendations for low salt intake in Korean population to prevent and control adverse blood pressure levels.

Analysis of Correlation between 24-Hour Urinary Sodium and the Degree of Blood Pressure Control in Patients with Chronic Kidney Disease and Non-Chronic Kidney Disease

We investigated the association between 24-hr urinary sodium (24UNA) and adequacy of blood pressure (BP) control in patients with chronic kidney disease (CKD) and nonCKD. All data were collected retrospectively by accessing the electrical medical records in patients with 24-hr urine collection and serum creatinine. Enrolled 400 subjects were subgrouped by the amount of 24UNA, or CKD stage. The appropriate BP was defined as BP or =90 mEq/day was 2.441 (1.249-4.772, P=0.009) higher than that of 24UNA <90 mEq/day among participants with proteinuria. There was difference in the amount of 24UNA between CKD and non-CKD except each stage of CKD group. In conclusion, salt intake estimated by 24-hr urine sodium excretion is a risk factor to achieve appropriate BP control.

Urinary Sodium Excretion Has Positive Correlation with Activation of Urinary Renin Angiotensin System and Reactive Oxygen Species in Hypertensive Chronic Kidney Disease

It is not well described the pathophysiology of renal injuries caused by a high salt intake in humans. The authors analyzed the relationship between the 24-hr urine sodium-to-creatinine ratio (24HUna/cr) and renal injury parameters such as urine angiotensinogen (uAGT/cr), monocyte chemoattractant peptide-1 (uMCP1/cr), and malondialdehyde-to-creatinine ratio (uMDA/cr) by using the data derived from 226 hypertensive chronic kidney disease patients. At baseline, the 24HUna/cr group or levels had a positive correlation with uAGT/cr and uMDA/cr adjusted for related factors (P or =200 mEq/g cr was higher than in patients with or =200 mEq/g cr (P=0.016). During the 16-week follow-up period, an increase in urinary sodium excretion predicted an increase in urinary angiotensinogen excretion. In conclusion, high salt intake increases renal renin-angiotensin-system (RAS) activation, primarily, and directly or indirectly affects the production of reactive oxygen species through renal RAS activation.

Estimated Amount of 24-Hour Urine Sodium Excretion Is Positively Correlated with Stomach and Breast Cancer Prevalence in Korea

Stomach cancer is one of the most common cancers in Korea. The aim of this study was to identify the association between the prevalence of cancer, particularly stomach cancer, and the amount of 24-hr urine sodium excretion estimated from spot urine specimens. The study included 19,083 subjects who took part in the Korean National Health and Nutritional Examination Survey between 2009 and 2011. The total amount of urine sodium excreted in a 24-hr period was estimated by using two equations based on the values for spot urine sodium and creatinine. In subjects who had an estimated 24-hr urine sodium excretion of more than two standard deviations above the mean (group 2), the prevalence of stomach cancer was higher than in subjects with lower 24-hr sodium excretion (group 1). By using the Tanaka equation to estimate it, the prevalence of stomach cancer was 0.6% (114/18,331) in group 1, whereas it was 1.6% (9/568) in group 2 (P=0.006). By using the Korean equation, the prevalence was 0.6% (115/18,392) in group 1, and 1.6% in group 2 (8/507) (P=0.010). By using the Tanaka equation, breast cancer in women is more prevalent in group 2 (1.9%, 6/324) than group 1 (0.8%, 78/9,985, P=0.039). Higher salt intake, as defined by the estimated amount of 24-hr urine sodium excretion, is positively correlated with a higher prevalence of stomach or breast cancer in the Korean population.

PREFACE

No abstract available.

Estimation of Daily Salt Intake through a 24-Hour Urine Collection in Pohang, Korea

There is an established relationship between a high salt diet and public health problems, especially hypertension and cardiovascular disease. We estimated daily salt intake in a group of adults and assessed its association with related variables in Pohang, Korea. We conducted a cross-sectional survey in 2013 with 242 adults. Urine was collected for 24 hr to estimate daily salt intake, and questionnaires about salt preference were administered. The mean daily salt intake was 9.9+/-4.6 g. There was no difference in salt intake between high systolic blood pressure (SBP) participants and normal SBP participants (10.5+/-4.7 g/d vs. 9.6+/-4.3 g/d, P=0.339), but high diastolic blood pressure (DBP) participants reported more salt intake than normal DBP participants (10.4+/-4.9 g/d vs. 9.7+/-4.1 g/d, P=0.049). Salt intake and body mass index demonstrated a positive correlation (P=0.001). A preference for Korean soup or stew was associated with high salt intake (P=0.038). Dietary salt intake in Korean adults is still higher than the recommendation from the World Health Organization. More efforts should be made to reduce the salt consumption of Korean adults.

Correction of Anemia with Continuous Erythropoietin Receptor Activator in Korean Patients on Long-Term Hemodialysis

Continuous erythropoietin receptor activator (CERA) is an erythropoietin with a long-half life. This study investigated the efficacy of CERA for correcting anemia in Korean patients on dialysis. Patients (> or =18 yr) who were not receiving any ESAs for more than 8 weeks were randomly assigned to either intravenous CERA once every 2 weeks (n=39) or epoetin beta thrice-weekly (n=41) during a 24-week correction phase. Hemoglobin (Hb) response was defined as increase of Hb by at least 1 g/dL and Hb> or =11 g/dL without red blood cell (RBC) transfusion. Median dialysis duration was 1.7 (0.3-20.8) and 1.6 (0.4-13.8) yr in CERA and epoetin beta group, respectively. Hemoglobin response rate of CERA was 79.5% (95% confidence interval [CI], 63.5-90.7). As the lower limit of 95% CI was higher than pre-specified 60% response rate, it can be concluded that CERA corrected anemia (P<0.05). Hb response rate of epoetin beta was 87.8% (95% CI, 73.8-95.9) (P=0.37). Median time to response was 12 weeks in CERA and 10.3 weeks in epoetin beta (P=0.03). It is suggested that once every 2 weeks administration of CERA is effective for correcting anemia in Korean patients on long-term hemodialysis with longer time-to-response than thrice weekly epoetin beta. (ClinicalTrials.gov registry No. NCT00546481)

A Case of High dose Colchicine with No Efficacy in a Patient with Chronic Kidney Disease Taking Rifampicin

A 54-year-old male on chronic hemodialysis, who was taking rifampicin for tuberculous lymphadenitis, was admitted for an acute gout attack. After administrating 3.6 mg of colchicine for 2 days, symptoms began to alleviate. Despite the relatively high dosage in this end-stage renal disease patient, there were no adverse effects, such as diarrhea, vomiting, or myopathy. After 1 and 6 hours of 0.6 mg colchicine administration, serum colchicine was 1.3930 ng/mL and 0.2464 ng/mL, respectively. These values were lower than the mean concentrations in 13 other patients with chronic kidney disease (CKD) after the same time intervals (4.34+/-0.56 ng/mL and 1.49+/-0.15 ng/mL, respectively). As rifampicin is an inducer of cytochrome P450 3A4, metabolism of colchicine had increased. When taking colchicine and rifampicin simultaneously, a higher colchicine dose may be needed for the treatment of acute gout in patients with CKD.

Small Increases in Plasma Sodium Are Associated with Higher Risk of Mortality in a Healthy Population

Elevated blood pressure (BP) is the most common cause of cardiovascular disease. Salt intake has a strong influence on BP, and plasma sodium (pNa) is increased with progressive increases in salt intake. However, the associations with pNa and BP had been reported inconsistently. We evaluated the association between pNa and BP, and estimated the risks of all-cause-mortality according to pNa levels. On the basis of data collected from health checkups during 1995-2009, 97,009 adult subjects were included. Positive correlations between pNa and systolic BP, diastolic BP, and pulse pressure (PP) were noted in participants with pNa > or =138 mM/L (P or =50 yr, SBP, DBP, and PP were positively associated with pNa. In participants with metabolic syndrome components, the differences in SBP and DBP according to pNa were greater (P or =50 yr during the median 4.2-yr-follow-up (P or =145 mM/L was related to mortality. The positive correlation between pNa and BP is stronger in older subjects, women, and subjects with metabolic syndrome components. The incidence and adjusted risks of mortality increase with increasing pNa in women aged > or =50 yr.

Clinical characteristics of acute renal failure with severe loin pain and patchy renal vasoconstriction

BACKGROUND: Acute renal failure (ARF) with severe loin pain and patchy renal vasoconstriction (PRV) is a syndrome presenting with sudden loin pain after anaerobic exercise. We aimed to investigate the clinical characteristics and the efficacy of diagnostic imaging studies of patients with this syndrome. METHODS: We retrospectively selected 17 patients with ARF accompanied by loin or abdominal pain who showed multiple patchy wedge-shaped delayed contrast enhancements on a computerized tomography scan. Information about the clinical characteristics, including the nature of pain and combined symptoms, suspected causes, such as exercise, drug or alcohol intake, and renal hypouricemia, and the results of laboratory and imaging tests were gathered. RESULTS: The mean age of patients with episodes of ARF accompanied by loin pain was 23.0+/-6.5 (range 16-35) years old. Pain was mainly located in the loin (70.6%) or abdominal area (76.5%) and continued for approximately 3.5+/-4.0 days. Exercise was suspected as a primary cause of disease in 12 (70.6%) patients. Maximal serum creatinine was 5.42+/-3.16 (1.4-12.1) mg/dL 3.1+/-1.8 (1-7) days after the onset of pain. The peak level of serum uric acid was 9.41+/-2.91 (6.0-15.8) mg/dL. All of the patients recovered to near-normal renal function, and one patient showed hypouricemia after recovery. CONCLUSION: ARF with severe loin pain and PRV can present with loin or abdominal pain, even without a history of anaerobic exercise. Careful history taking and appropriate imaging studies are critical in the diagnosis and management of this syndrome.

Laparoscopic biopsy-proven lupus nephritis in autosomal dominant polycystic kidney disease

A 48-year-old woman with autosomal dominant polycystic kidney disease (ADPKD) presented with generalized edema and arthralgia. She showed evidences of acute glomerulonephritis including nephrotic-ranged proteinuria. Because her serologic test results were consistent with those for systemic lupus erythematosus (SLE), we performed laparoscopic renal biopsy that confirmed World Health Organization (WHO) class IV lupus nephritis. She was treated with steroids and intravenous cyclophosphamide pulse therapy and eventually started hemodialysis 8 years after the lupus nephritis was diagnosed. To our knowledge, this is the first case wherein a patient with ADPKD underwent a laparoscopic biopsy for diagnosing lupus nephritis.

Complete remission induced by tacrolimus and low-dose prednisolone in adult minimal change nephrotic syndrome: A pilot study

BACKGROUND: Few clinical trials have examined the replacement of steroids with other immunosuppressive drugs as a primary treatment modality for minimal change disease (MCD) in adults. We studied the efficacy of tacrolimus to induce complete remission (CR) in adults with MCD. METHODS: We enrolled 14 adults with MCD and nephrotic-range proteinuria. All patients were treated with oral tacrolimus 0.05mg/kg twice daily and prednisolone 0.5mg/kg/day. CR was defined as a urine protein to creatinine ratio of<0.2g protein/g creatinine (g/g cr). The primary outcome was cumulative percentage of CR during 16 weeks. RESULTS: The mean urine protein to creatinine ratio at enrollment was 10.9g/g cr (range: 4.2-18.1g/g cr). The trough tacrolimus level was maintained at 5.99+/-2.63ng/mL. CR was achieved by 13/14 (92.8%) patients within 8 weeks. The cumulative CR rate was 7.7% (1/14), 64.2% (9/14), 71.3% (10/14), and 92.9% (13/14) at 1 week, 2 weeks, 4 weeks, and 8 weeks, respectively. The one remaining patient achieved CR at 20 weeks after treatment, who was followed up for a further 4 weeks. The mean time to achieve CR in the 14 patients was 4.64+/-5.11 (1-20) weeks. Three cases suffered adverse events of abdominal pain, diarrhea, or new-onset diabetes mellitus. CONCLUSION: Tacrolimus and low-dose prednisolone therapy induced CR rapidly (71.3% by 4 weeks and 100% by 20 weeks) and effectively in adult patients with MCD.

The effect of depression and health-related quality of life on the outcome of hemodialysis patients

BACKGROUND: In hemodialysis (HD) patients, traditional risk factors cannot explain all of the mortality and morbidity. This study was designed to investigate the effect of depression and health-related quality of life (HRQOL) on prognosis in maintenance HD patients. METHODS: In February 2008, the Beck's Depression Inventory and the Kidney Dialysis Quality of Life-Short Form were utilized to measure depression and HRQOL. Until February 2011, the mortality, cardiovascular events, infection, and hospitalization were investigated, retrospectively. RESULTS: Among the 166 patients, the 3-year cumulative survival rate was 88.8%, and the depression did not affect survival (depression vs. nondepression: 91.8% vs. 87.2%, P=0.437). The upper tertiles in physical component summary (PCS) were correlated with lower mortality (OR, 0.12; P=0.05) and fewer cardiovascular events (OR, 0.09; P=0.024) than the lower tertiles. The upper tertiles in kidney disease component summary (KDCS) were associated with less hospitalization than the lower tertiles (OR, 0.38; P=0.024). After adjusting for multiple variables including age, comorbidity index, and albumin, upper tertiles in PCS were correlated with fewer cardiovascular events than the lower tertiles (OR, 0.08; P=0.038). CONCLUSION: The cross-sectional survey of whether HD patients had depression was not significantly associated with mortality and morbidity. HRQOL was correlated with mortality, cardiovascular events and hospitalization.