Effects of diet and exercise on adipocytokine levels in patients with moderate to severe chronic kidney disease

Effects of Nutritional Supplementation Combined With Exercise Training on Frailty, Physical Function, and Quality of Life in Chronic Kidney Disease: A Systematic Review and Meta-Analysis

This review evaluates the effectiveness of nutritional supplementation combined with exercise training on frailty characteristics, physical function, and health-related quality of life in patients with chronic kidney disease (CKD). A systematic search of PubMed, Embase, Web of Science, and Scopus was conducted, identifying 7 articles (9 trials, 324 patients). Meta-analysis showed that combined interventions improved frailty characteristics, such as walking speed (mean difference: 0.09 m/s, 95% confidence interval (CI): 0.02 to 0.16) and physical functioning, including cardiorespiratory fitness (standardized mean difference: 0.56, 95% CI: 0.20 to 0.93) and lower extremity mobility (Timed Up and Go test: -1.11 s, 95% CI: -1.79 to -0.43). However, effects on body weight, fatigue, and health-related quality of life remain uncertain. Due to study heterogeneity and small sample sizes, findings should be interpreted cautiously. Larger, long-term studies are needed to confirm these results and explore additional health outcomes.

Strength Training can Modulate Urinary Adipokine Levels in Healthy Young Males

Adipose tissue stores energy in fat-rich adipocytes, which can produce and release several adipokines and modulate body metabolism. Exercise may induce adipokine production in adipocytes; however, the relationship between the two remains unclear. Few studies have shown the relationship between adipokines and strength training. Thus, we aimed to evaluate the acute and chronic effects of strength training (ST) on urinary adiponectin, leptin, and resistin levels. Twelve untrained young men (23.42 ± 2.67 years) were included in this study. Body composition was evaluated at baseline and after completing of the training protocol using densitometry. Training protocol consisted of three exercises with three sets of 65% of one-repetition maximum (1MR) with a pause of 90 s between sets, each exercise lasting 5 s (2 s concentric / 3 s eccentric). The sessions were carried out three times a week for 10 weeks. Urine was collected during the pre- and post-training in the first and 30th session. Adipokine levels were determined by ELISA. Urinary levels of leptin acutely increased after the first ST session, and after the last ST session. Chronic changes in the leptin levels were also found when comparing the values before the last ST and before the first ST session. Urinary adiponectin levels changed in the comparison of values before and after the last session. There was a significant increase in the adiponectin levels when comparing values after the first and last ST sessions. The levels of resistin chronically increased. Strength training can induce acute and chronic changes in urinary levels of adipokines.

Time-restricted feeding's effect on overweight and obese patients with chronic kidney disease stages 3-4: A prospective non-randomized control pilot study

Background

Time-restricted feeding (TRF) has become a popular weight loss method in recent years. It is widely used in the nutritional treatment of normal obese people and obese people with chronic diseases such as diabetes mellitus and hypertension, and has shown many benefits. However, most TRF studies have excluded chronic kidney disease (CKD) patients, resulting in a lack of sufficient evidence-based practice for the efficacy and safety of TRF therapy for CKD. Therefore, we explore the efficacy and safety of TRF in overweight and obese patients with moderate-to-severe stage CKD through this pilot study, and observe patient compliance to assess the feasibility of the therapy.

Methods

This is a prospective, non-randomized controlled short-term clinical trial. We recruited overweight and obese patients with CKD stages 3-4 from an outpatient clinic and assigned them to either a TRF group or a control diet (CD) group according to their preferences. Changes in renal function, other biochemical data, anthropometric parameters, gut microbiota, and adverse events were measured before the intervention and after 12 weeks.

Results

The change in estimated glomerular filtration rate (eGFR) before and after intervention in the TRF group (Δ = 3.1 ± 5.3 ml/min/1.73m2) showed significant improvement compared with the CD group (Δ = -0.8 ± 4.4 ml/min/1.73m2). Furthermore, the TRF group had a significant decrease in uric acid (Δ = -70.8 ± 124.2 μmol/L), but an increase in total protein (Δ = 1.7 ± 2.5 g/L), while the changes were inconsistent for inflammatory factors. In addition, the TRF group showed a significant decrease in body weight (Δ = -2.8 ± 2.9 kg) compared to the CD group, and body composition indicated the same decrease in body fat mass, fat free mass and body water. Additionally, TRF shifted the gut microbiota in a positive direction.

Conclusion

Preliminary studies suggest that overweight and obese patients with moderate-to-severe CKD with weight loss needs, and who were under strict medical supervision by healthcare professionals, performed TRF with good compliance. They did so without apparent adverse events, and showed efficacy in protecting renal function. These results may be due to changes in body composition and alterations in gut microbiota.

The impact of exercise and dietary interventions on circulating leptin and adiponectin in individuals who are overweight and those with obesity: A systematic review and meta-analysis

The effects of exercise training (Ex), dietary interventions (DIs), and a combination of Ex and DI (Ex + DI) on leptin and adiponectin have been established. However, less is known regarding the comparisons of Ex with DI and of Ex + DI with either Ex or DI alone. The aim of the present meta-analysis is to compare the effects of Ex with those of DI and those of Ex + DI with those of either Ex or DI alone on circulating leptin and adiponectin in individuals who are overweight and those with obesity. PubMed, Web of Science, and MEDLINE were searched to identify original articles, published through June 2022, that compared the effects of Ex with those of DI and/or the effects of Ex + DI with those of Ex and/or DI on leptin and adiponectin in individuals with BMIs (in kg/m²) of ≥25 and aged 7-70 y. Standardized mean differences (SMDs), weighted mean differences, and 95% CIs were calculated using random-effect models for outcomes. Forty-seven studies, comprising 3872 participants who were overweight and those with obesity, were included in the current meta-analysis. DI reduced the concentration of leptin (SMD: -0.30; P = 0.001) and increased the concentration of adiponectin (SMD: 0.23; P = 0.001) compared with Ex, as did Ex + DI (leptin: SMD: -0.34; P = 0.001; adiponectin: SMD: 0.37; P = 0.004) compared with Ex alone. However, Ex + DI did not affect the concentration of adiponectin (SMD: 0.10; P = 0.11) and led to inconsistent and nonsignificant changes in the concentration of leptin (SMD: -0.13; P = 0.06) compared with DI alone. Subgroup analyses showed that age, BMI, duration of intervention, type of supervision, quality of the study, and magnitude of energy restriction are sources of heterogeneity. Our results suggest that Ex alone was not as effective as DI or Ex + DI for decreasing leptin and increasing adiponectin in individuals with overweight and obesity. However, Ex + DI was not more effective than DI alone, suggesting that diet plays a critical role in beneficially altering the concentrations of leptin and adiponectin. This review was registered at PROSPERO as CRD42021283532.

The Effect of Nutrition and Exercise on Body Composition, Exercise Capacity, and Physical Functioning in Advanced CKD Patients

Patients with stages 4 and 5 chronic kidney disease (CKD), and particularly chronic dialysis patients, commonly are found to have substantially reduced daily physical activity in comparison to age- and sex-matched normal adults. This reduction in physical activity is associated with a major decrease in physical exercise capacity and physical performance. The CKD patients are often physically deconditioned, and protein energy wasting (PEW) and frailty are commonly present. These disorders are of major concern because physical dysfunction, muscle atrophy, and reduced muscle strength are associated with poor quality of life and increased morbidity and mortality in CKD and chronic dialysis patients. Many randomized controlled clinical trials indicate that when CKD and chronic dialysis are provided nutritional supplements or undergo exercise training their skeletal muscle mass and exercise capacity often increase. It is not known whether the rise in skeletal muscle mass and exercise capacity associated with nutritional support or exercise training will reduce morbidity or mortality rates. A limitation of these clinical trials is that the sample sizes of the different treatment groups were small. The aim of this review is to discuss the effects of nutrition and exercise on body composition, exercise capacity, and physical functioning in advanced CKD patients.

Nutritional Status, Selected Nutrients Intake and Their Relationship with the Concentration of Ghrelin and Adiponectin in Patients with Diabetic Nephropathy

Background: Overnutrition is one of the risk factors of chronic kidney disease (CKD). The factors related to both obesity and CKD are adiponectin and ghrelin. The aim of the study was to assess if there is a link of nutritional status and selected nutrients intake with adiponectin and ghrelin in patients with diabetic nephropathy (DN). Methods: The study involved 55 patients diagnosed with DN in the pre-dialysis period (two groups: GFR < 30 and >30 mL/min/1.73 m²). In all participants standard blood tests, total ghrelin and total adiponectin plasma concentrations and anthropometric measurements (BMI, WHR- waist–hip ratio, body composition analysis) were performed. The evaluation of energy and nutrient intakes was made using the three-day food record method. Results: Excessive body weight was found in 92.80% patients. The average daily energy intake was 1979.67 kcal/day (14.45% protein energy, 28.86% fat, and carbohydrates 56.89%). In the group with eGFR < 30 mL/min/1.73 m² the analysis showed a negative relationship between ghrelin and WHR value, and the creatine and albumin concentrations. There was a positive correlation between ghrelin concentration and the consumption of carbohydrates and sucrose. In the group of patients with eGFR > 30 mL/min/1.73 m², a positive correlation was found between the concentration of ghrelin and the consumption of vegetable protein, carbohydrates, and glucose. Conclusions: The study confirms the high prevalence of obesity in patients with DN-Excessive supply of protein was found in the patients’ diets, which may contribute to the deterioration of the course of the disease and its prognosis. In patients with eGFR < 30 there was a negative correlation between ghrelin concentration and nutritional status, and in patents with eGFR > 30 between ghrelin concentration and some nutrients intake.

Effects of pre-pregnancy body mass index on pregnancy and perinatal outcomes in women based on a retrospective cohort

To investigate the prevalence of underweight, overweight and obesity as defined by pre-pregnancy body mass index (BMI) and the relationship between pre-pregnancy BMI and pregnancy and perinatal outcomes in women based on a retrospective cohort. Women registered via the Free Pre-pregnancy Health Check (FPHC) program from 2017 to 2019 in Hunan Province, China, were included to the study cohort. The data regarding maternal characteristics, pregnancy outcomes, and infant characteristics were retrieved from the surveillance system of the FPHC program. Logistic regressions were performed to calculate odds ratios (ORs) and adjusted odds ratios (AORs) with 95% confidence intervals (95% CIs) to assess the associations between pre-pregnancy BMIs and the outcomes. Among a total of 398,368 women, 54,238 (13.62%) were underweight (BMI < 18.5 kg/m2), 51,251 (12.87%) were overweight (24.0 kg/m2 ≤ BMI < 28.0 kg/m2), and 10,399 (2.61%) were obese (BMI ≥ 28.0 kg/m2). Underweight occurred more commonly in the 20-24 years old (17.98%), Han Chinese (13.89), college-educated (16.09%), rural (13.74%), and teacher/public servant/office clerk (16.09%) groups. Obesity occurred more often in the older than 35-year-old (4.48%), minority (3.64%), primary school or below (4.98%), urban (3.06%), and housewife (3.14%) groups (P < 0.001). Compared with the normal BMI group, underweight was associated with increased risk of low birth weight (LBW) (AOR = 1.25) and small-for-gestational age (SGA) (AOR = 1.11), but protected against gestational hypertensive disorder (GHD) (AOR = 0.85), gestational diabetes mellitus (GDM) (AOR = 0.69), macrosomia (AOR = 0.67), post-term pregnancy (AOR = 0.76), and cesarean-section (AOR = 0.81). Overweight and obesity were associated with increased risk of GHD (AOR = 1.28, 2.47), GDM (AOR = 1.63, 3.02), preterm birth (AOR = 1.18, 1.47), macrosomia (AOR = 1.51, 2.11), large-for-gestational age (LGA) (AOR = 1.19, 1.35), post-term pregnancy (AOR = 1.39, 1.66), and cesarean- section (AOR = 1.60, 2.05). Pre-pregnancy underweight is relatively common in Hunan Province, China. Pre-pregnancy underweight to some extent is associated with better maternal outcomes, but it has certain adverse effects on neonatal outcomes. Pre-pregnancy overweight, especially obesity, has a substantial adverse effect on pregnancy and perinatal outcomes.

NADH/NAD+ Redox Imbalance and Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common and severe complication of diabetes mellitus. If left untreated, DKD can advance to end stage renal disease that requires either dialysis or kidney replacement. While numerous mechanisms underlie the pathogenesis of DKD, oxidative stress driven by NADH/NAD⁺ redox imbalance and mitochondrial dysfunction have been thought to be the major pathophysiological mechanism of DKD. In this review, the pathways that increase NADH generation and those that decrease NAD⁺ levels are overviewed. This is followed by discussion of the consequences of NADH/NAD⁺ redox imbalance including disruption of mitochondrial homeostasis and function. Approaches that can be applied to counteract DKD are then discussed, which include mitochondria-targeted antioxidants and mimetics of superoxide dismutase, caloric restriction, plant/herbal extracts or their isolated compounds. Finally, the review ends by pointing out that future studies are needed to dissect the role of each pathway involved in NADH-NAD⁺ metabolism so that novel strategies to restore NADH/NAD⁺ redox balance in the diabetic kidney could be designed to combat DKD.

Interventions for weight loss in people with chronic kidney disease who are overweight or obese

BACKGROUND

Obesity and chronic kidney disease (CKD) are highly prevalent worldwide and result in substantial health care costs. Obesity is a predictor of incident CKD and progression to kidney failure. Whether weight loss interventions are safe and effective to impact on disease progression and clinical outcomes, such as death remains unclear.

OBJECTIVES

This review aimed to evaluate the safety and efficacy of intentional weight loss interventions in overweight and obese adults with CKD; including those with end-stage kidney disease (ESKD) being treated with dialysis, kidney transplantation, or supportive care.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 14 December 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of more than four weeks duration, reporting on intentional weight loss interventions, in individuals with any stage of CKD, designed to promote weight loss as one of their primary stated goals, in any health care setting.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and extracted data. We applied the Cochrane 'Risk of Bias' tool and used the GRADE process to assess the certainty of evidence. We estimated treatment effects using random-effects meta-analysis. Results were expressed as risk ratios (RR) for dichotomous outcomes together with 95% confidence intervals (CI) or mean differences (MD) or standardised mean difference (SMD) for continuous outcomes or in descriptive format when meta-analysis was not possible.

MAIN RESULTS

We included 17 RCTs enrolling 988 overweight or obese adults with CKD. The weight loss interventions and comparators across studies varied. We categorised comparisons into three groups: any weight loss intervention versus usual care or control; any weight loss intervention versus dietary intervention; and surgical intervention versus non-surgical intervention. Methodological quality was varied, with many studies providing insufficient information to accurately judge the risk of bias. Death (any cause), cardiovascular events, successful kidney transplantation, nutritional status, cost effectiveness and economic analysis were not measured in any of the included studies. Across all 17 studies many clinical parameters, patient-centred outcomes, and adverse events were not measured limiting comparisons for these outcomes. In studies comparing any weight loss intervention to usual care or control, weight loss interventions may lead to weight loss or reduction in body weight post intervention (6 studies, 180 participants: MD -3.69 kg, 95% CI -5.82 to -1.57; follow-up: 5 weeks to 12 months, very low-certainty evidence). In very low certainty evidence any weight loss intervention had uncertain effects on body mass index (BMI) (4 studies, 100 participants: MD -2.18 kg/m², 95% CI -4.90 to 0.54), waist circumference (2 studies, 53 participants: MD 0.68 cm, 95% CI -7.6 to 6.24), proteinuria (4 studies, 84 participants: 0.29 g/day, 95% CI -0.76 to 0.18), systolic (4 studies, 139 participants: -3.45 mmHg, 95% CI -9.99 to 3.09) and diastolic blood pressure (4 studies, 139 participants: -2.02 mmHg, 95% CI -3.79 to 0.24). Any weight loss intervention made little or no difference to total cholesterol, high density lipoprotein cholesterol, and inflammation, but may lower low density lipoprotein cholesterol. There was little or no difference between any weight loss interventions (lifestyle or pharmacological) compared to dietary-only weight loss interventions for weight loss, BMI, waist circumference, proteinuria, and systolic blood pressure, however diastolic blood pressure was probably reduced. Furthermore, studies comparing the efficacy of different types of dietary interventions failed to find a specific dietary intervention to be superior for weight loss or a reduction in BMI. Surgical interventions probably reduced body weight (1 study, 11 participants: MD -29.50 kg, 95% CI -36.4 to -23.35), BMI (2 studies, 17 participants: MD -10.43 kg/m², 95% CI -13.58 to -7.29), and waist circumference (MD -30.00 cm, 95% CI -39.93 to -20.07) when compared to non-surgical weight loss interventions after 12 months of follow-up. Proteinuria and blood pressure were not reported. All results across all comparators should be interpreted with caution due to the small number of studies, very low quality of evidence and heterogeneity across interventions and comparators.

AUTHORS' CONCLUSIONS

All types of weight loss interventions had uncertain effects on death and cardiovascular events among overweight and obese adults with CKD as no studies reported these outcome measures. Non-surgical weight loss interventions (predominately lifestyle) appear to be an effective treatment to reduce body weight, and LDL cholesterol. Surgical interventions probably reduce body weight, waist circumference, and fat mass. The current evidence is limited by the small number of included studies, as well as the significant heterogeneity and a high risk of bias in most studies.