The implication of calf circumference and grip strength in osteoporosis and bone mineral density among hemodialysis patients.

BACKGROUND: Chronic kidney disease-mineral and bone disorder (CKD-MBD), nutritional status, and uremia management have been emphasized for bone management in hemodialysis patients. Nevertheless, valuable data on the importance of muscle mass in bone management are limited, including whether conventional management alone can prevent osteoporosis. Thus, the importance of muscle mass and strength, independent of the conventional management in osteoporosis prevention among hemodialysis patients, was evaluated. METHODS: Patients with a history of hemodialysis 6 months or longer were selected. We assessed the risk for osteoporosis associated with calf circumference or grip strength using multivariable adjustment for indices of CKD-MBD, nutrition, and dialysis adequacy. Moreover, the associations between bone mineral density (BMD), calf circumference, grip strength, and bone metabolic markers were also evaluated. RESULTS: A total of 136 patients were included. The odds ratios (95% confidence interval) for osteoporosis at the femoral neck were 1.25 (1.04-1.54, P < 0.05) and 1.08 (1.00-1.18, P < 0.05) per 1 cm shorter calf circumference or 1 kg weaker grip strength, respectively. Shorter calf circumference was significantly associated with a lower BMD at the femoral neck and lumbar spine (P < 0.001). Weaker grip strength was also associated with lower BMD at the femoral neck (P < 0.01). Calf circumference or grip strength was negatively correlated with bone metabolic marker values. CONCLUSION: Shorter calf circumference or weaker grip strength was associated with osteoporosis risk and lower BMD among hemodialysis patients, independent of the conventional therapies.

Omega-3 Fatty Acids Reduce Remnant-like Lipoprotein Cholesterol and Improve the Ankle-Brachial Index of Hemodialysis Patients with Dyslipidemia: A Pilot Study.

Background and Objectives: Omega-3 fatty acids have potent lipid-lowering and antiplatelet effects; however, randomized controlled trials have yet to examine the effect of high-dose omega-3 fatty acid administration on peripheral artery disease (PAD) in hemodialysis patients with dyslipidemia. Therefore, this study aimed to evaluate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the ankle-brachial index (ABI) and remnant-like lipoprotein cholesterol (RLP-C) levels, which are indicators of PAD severity. Materials and Methods: Thirty-eight participants (mean age: 73.6 ± 12.7 years) were randomly assigned using stratified block randomization to either conventional therapy alone or conventional therapy supplemented with high-dose EPA/DHA (EPA: 1860 mg; DHA: 1500 mg) for a three-month intervention period. Patients in the conventional therapy alone group who opted to continue were provided with a low-dose EPA/DHA regimen (EPA: 930 mg; DHA: 750 mg) for an additional three months. The baseline and 3-month values for RLP-C, an atherogenic lipid parameter, and the ABI were recorded. Results: The results of the 3-month assessments revealed that the mean RLP-C changes were -3.25 ± 3.15 mg/dL and 0.44 ± 2.53 mg/dL in the EPA/DHA and control groups, respectively (p < 0.001), whereas the changes in the mean ABI values were 0.07 ± 0.11 and -0.02 ± 0.09 in the EPA/DHA and control groups, respectively (p = 0.007). In the EPA/DHA group, a significant negative correlation was found between the changes in RLP-C levels and the ABI (r = -0.475, p = 0.04). Additionally, the change in the RLP-C levels independently influenced the change in the ABI in the EPA/DHA group, even after adjusting for age, sex, and statin use (p = 0.042). Conclusions: Add-on EPA/DHA treatment improved the effectiveness of conventional therapy (such as statin treatment) for improving the ABI in hemodialysis patients with dyslipidemia by lowering RLP-C levels. Therefore, clinicians involved in dialysis should focus on RLP-C when considering residual cardiovascular disease risk in hemodialysis patients and should consider screening patients with elevated levels.

Efficacy of tolvaptan on advanced chronic kidney disease with heart failure: a randomized controlled trial.

BACKGROUND: Tolvaptan (TLV) is reported to improve diuretic effects in patients with chronic kidney disease (CKD) when furosemide (FUR) is not sufficiently effective. However, it is not clear whether TLV addition is effective for advanced CKD patients with heart failure. METHODS: An open-label, parallel-group randomized trial was performed. The subjects were 33 patients with CKD stage G3-G5 who had fluid overload despite taking 20-100 mg/day FUR. They were divided into two groups: a group administered 15 mg/day TLV plus their original FUR dose for 7 days (TLV group), and a group administered 120-200 mg/day FUR (i.e., 100 mg/day over their previous dose) for 7 days (FUR group). RESULTS: The mean change in urine volume was significantly higher in the TLV group compared to the FUR group (637 ml vs 119 ml; p < 0.05). The difference was greater when the urine osmolality before treatment was high. Serum creatinine was increased only in the FUR group. The incidence of worsening renal function (WRF) was significantly lower in the TLV group (18.8% vs 58.8%; p < 0.05). Serum sodium decreased significantly in the FUR group, but did not change in the TLV group. CONCLUSIONS: In patients with advanced CKD with fluid overload, the addition of TLV achieved a significantly higher urine volume with less adverse effects on renal function compared with increasing the dose of FUR. The efficacy and safety of TLV were higher in patients who had higher urine osmolality and lower serum sodium before treatment. CLINICAL TRIAL REGISTRATION: UMIN000014763.

ATP2B1 gene polymorphisms associated with resistant hypertension in the Japanese population.

Single-nucleotide polymorphisms (SNP) of ATP2B1 gene are associated with essential hypertension but their association with resistant hypertension (RHT) remains unexplored. The authors examined the relationship between ATP2B1 SNPs and RHT by genotyping 12 SNPs in ATP2B1 gene of 1124 Japanese individuals with lifestyle-related diseases. Patients with RHT had inadequate blood pressure (BP) control using three antihypertensive drugs or used ≥4 antihypertensive drugs. Patients with controlled hypertension had BP controlled using ≤3 antihypertensive drugs. The association between each SNP and RHT was analyzed by logistic regression. The final cohort had 888 (79.0%) and 43 (3.8%) patients with controlled hypertension and RHT, respectively. Compared with patients homozygous for the minor allele of each SNP in ATP2B1, a significantly higher number of patients carrying the major allele at 10 SNPs exhibited RHT (most significant at rs1401982: 5.8% vs. 0.8%, p = .014; least significant at rs11105378: 5.7% vs. 0.9%, p = .035; most nonsignificant at rs12817819: 5.1% vs. 10%, p = .413). After multivariate adjustment for age, sex, systolic BP, and other confounders, the association remained significant for rs2681472 and rs1401982 (OR: 7.60, p < .05 and OR: 7.62, p = .049, respectively). Additionally, rs2681472 and rs1401982 were in linkage disequilibrium with rs11105378. This study identified two ATP2B1 SNPs associated with RHT in the Japanese population. rs1401982 was most closely associated with RHT, and major allele carriers of rs1401982 required significantly more antihypertensive medications. Analysis of ATP2B1 SNPs in patients with hypertension can help in early prediction of RHT and identification of high-risk patients who are more likely to require more antihypertensive medications.

Effectiveness of DialBetesPlus, a self-management support system for diabetic kidney disease: Randomized controlled trial.

We evaluated the effectiveness of a mobile health (mHealth) intervention for diabetic kidney disease patients by conducting a 12-month randomized controlled trial among 126 type 2 diabetes mellitus patients with moderately increased albuminuria (urinary albumin-to-creatinine ratio (UACR): 30-299 mg/g creatinine) recruited from eight clinical sites in Japan. Using a Theory of Planned Behavior (TPB) behavior change theory framework, the intervention provides patients detailed information in order to improve patient control over exercise and dietary behaviors. In addition to standard care, the intervention group received DialBetesPlus, a self-management support system allowing patients to monitor exercise, blood glucose, diet, blood pressure, and body weight via a smartphone application. The primary outcome, change in UACR after 12 months (used as a surrogate measure of renal function), was 28.8% better than the control group's change (P = 0.029). Secondary outcomes also improved in the intervention group, including a 0.32-point better change in HbA1c percentage (P = 0.041). These improvements persisted when models were adjusted to account for the impacts of coadministration of drugs targeting albuminuria (GLP-1 receptor agonists, SGLT-2 inhibitors, ACE inhibitors, and ARBs) (UACR: -32.3% [95% CI: -49.2%, -9.8%] between-group difference in change, P = 0.008). Exploratory multivariate regression analysis suggests that the improvements were primarily due to levels of exercise. This is the first trial to show that a lifestyle intervention via mHealth achieved a clinically-significant improvement in moderately increased albuminuria.

LPIN1 is a new target gene for essential hypertension.

BACKGROUND: We previously showed Lipin1 (LPIN1) to be a candidate gene for essential hypertension by genome-wide association studies. LPIN1 encodes the Lipin 1 protein, which contributes to the maintenance of lipid metabolism and glucose homeostasis. However, little is known about the association between LPIN1 and blood pressure (BP). METHODS: We evaluated the BP of LPIN1-deficient [fatty liver dystrophy (fld)] mice and explored related mechanisms. RESULTS: Fld mice have very low expression of LPIN1 and exhibit fatty liver, hypertriglyceridemia, insulin resistance and peripheral neuropathy. Fld mice had significantly elevated SBP and heart rate (HR) throughout the day as measured by a radiotelemetric method. Diurnal variation of SBP and HR was also absent in fld mice. Furthermore, urinary excretion of adrenaline and noradrenaline by fld mice was significantly higher compared with that of control mice. The BP response of fld mice to clonidine (a centrally acting α2-adrenergic receptor agonist) was greater than that of control mice. However, levels of Angiotensinogen and Renin 1 mRNA and urinary nitric oxide excretion were comparable between the two groups. The decrease in SBP at 8 weeks after fat grafting surgery was significantly greater in the transplant group compared with the sham operated group. CONCLUSION: The elevated BP in fld mice may result from activation of the sympathetic nervous system through decreased levels of adipose cytokines. These results indicate that LPIN1 plays a crucial role in blood pressure regulation and that LPIN1 is a new target gene for essential hypertension.

Association of the ratio of visceral-to-subcutaneous fat volume with renal function among patients with primary aldosteronism.

Patients with primary aldosteronism have a higher risk of chronic kidney disease. Visceral fat tissue is hypothesized to stimulate the adrenal glands to overproduce aldosterone, and aldosterone promotes visceral fat tissue to produce inflammatory cytokines. However, it is unclear whether the volume of accumulated visceral fat tissue is associated with renal impairment among patients with hyperaldosteronism. We conducted a single-center cross-sectional study to assess the association between the estimated glomerular filtration rate and the ratio of the visceral-to-subcutaneous fat volume calculated by computed tomography. One hundred eighty patients with primary aldosteronism were enrolled. The mean ± SD age was 52.7 ± 11.0 years, and 60.0% were women. The ratio of visceral-to-subcutaneous fat volume was highly correlated with the estimated glomerular filtration rate (r = 0.49, p < 0.001). In multiple linear regression models, the ratio of visceral-to-subcutaneous fat tissue volume was significantly associated with the estimated glomerular filtration rate (estimates: -4.56 mL/min/1.73 m² per 1-SD), and there was an interaction effect between the plasma aldosterone concentration and the ratio of visceral-to-subcutaneous fat volume (p < 0.05). The group with a higher plasma aldosterone concentration exhibited a steeper decline in eGFR than the lower plasma aldosterone concentration group when the ratio increased. The ratio of visceral-to-subcutaneous fat tissue volume was an independent risk factor for renal dysfunction. This association increased in the presence of a high plasma aldosterone concentration. Clinicians should pay attention to the ratio of visceral-to-subcutaneous fat tissue volume and encourage primary aldosteronism patients to improve their lifestyle in addition to treating renin-aldosterone activity.

Efficacy of the Self-management Support System DialBetesPlus for Diabetic Kidney Disease: Protocol for a Randomized Controlled Trial.

BACKGROUND: Diabetic kidney disease (DKD) is one of the main complications of type 2 diabetes mellitus (T2DM). DKD is a known risk factor for end-stage renal disease, cardiovascular disease, and all-cause death. Effective intervention for early-stage DKD is vital to slowing down the progression of kidney disease and improve prognoses. Mobile health (mHealth) is reportedly effective in supporting patients' self-care and improving glycemic control, but the impact of mHealth on DKD has yet to be shown. OBJECTIVE: The purpose of this study is to evaluate the efficacy of standard therapy with the addition of a self-management support system, DialBetesPlus, in patients with DKD and microalbuminuria. METHODS: This study is a prospective, randomized, open-label, multicenter clinical trial. The target population consists of 160 patients diagnosed with T2DM accompanied by microalbuminuria. We randomly assigned the patients to 2 groups-the intervention group using DialBetesPlus in addition to conventional therapy and the control group using conventional therapy alone. DialBetesPlus is a smartphone application that supports patients' self-management of T2DM. The study period was 12 months, with a follow-up survey at 18 months. The primary outcome was a change in albuminuria levels at 12 months. Secondary outcomes included changes in physical parameters, blood test results (glycemic control, renal function, and lipid metabolism), lifestyle habits, self-management scores, medication therapy, and quality of life. RESULTS: The study was approved in April 2018. We began recruiting patients in July 2018 and completed recruiting in August 2019. The final 18-month follow-up was conducted in March 2021. We recruited 159 patients and randomly allocated 70 into the intervention group and 61 into the control group, with 28 exclusions due to withdrawal of consent, refusal to continue, or ineligibility. The first results are expected to be available in 2021. CONCLUSIONS: This is the first randomized controlled trial assessing the efficacy of mHealth on early-stage DKD. We expect that albuminuria levels will decrease significantly in the intervention group due to improved glycemic control with ameliorated self-care behaviors. TRIAL REGISTRATION: UMIN-CTR UMIN000033261; https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000037924. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/31061.