Physical exercise in kidney disease: A commonly undervalued treatment modality

Pretransplant Physical Activity and Cardiovascular Risk Factors in Kidney Transplant Candidates: A Cross-Sectional Study

Background/Objectives: Individuals with chronic kidney disease often face significant physical and clinical challenges, such as muscle weakness, fatigue, and reduced cardiorespiratory capacity, that impact their quality of life. Physical activity has emerged as an effective intervention to counteract these effects, with clinical guidelines recommending exercise as a standard treatment for kidney transplant recipients. The aim of this study was to assess pretransplant physical activity levels in a cohort of transplant patients and analyze their relationships with cardiovascular risk factors. Methods: A cross-sectional, analytical, and correlational study was conducted from September 2020 to June 2022 with a sample of 122 kidney transplant recipients assessed before kidney transplantation. Sociodemographic data, anthropometric data, comorbidities, renal replacement therapy types, and clinical and analytical data were collected from the patients' clinical records. Physical activity was assessed via the International Physical Activity Questionnaire. Results: The average time spent waiting for transplantation was 423 ± 405 days, which was longer (387 ± 524) in the group of those under 65 years than in those over 65 years (194 ± 256) (p = 0.010). The median energy expenditure was 1742 (IQR = 1719) METs. In addition, 15.6% of the participants reported inactivity. Men reported higher physical activity levels (median: 2076 METs/week; IQR: 2037) than women did (median: 1386 METs/week; IQR: 1238). A higher level of physical activity was found in non-dialysis patients, overweight patients, and those with a history of stroke. A significant positive correlation was found between physical activity levels and serum urea. Conclusions: Increased physical activity levels were observed in men and in participants under 65 years of age. Patients with cardiovascular risk factors, such as hypertension, diabetes mellitus, dyslipidemia, overweight and obesity, reported lower activity levels, whereas those with a prior history of cerebrovascular accidents engaged in more physical activity. This study highlights the importance of assessing physical activity and promoting exercise for chronic kidney disease patients awaiting kidney transplantation. Further research is needed to explore the evolution of physical activity in this population and its impact post-transplantation.

Global trends in chronic kidney disease mortality and disability-adjusted life years attributable to low physical activity (1990-2021): a growing public health challenge

BACKGROUND

Low physical activity (LPA) is a major contributor to the global burden of chronic kidney disease (CKD). Our goal was to assess the spatiotemporal trends in the CKD burden attributable to LPA from 1990 to 2021, with a focus on the globe, China, five SDI regions, and four continents.

METHODS

We analysed CKD-related deaths, DALYs, the ASMR, the ASDR, and the EAPC attributable to low physical activity (LPA). This study focused on trends from 1990 to 2021 across the globe, China, five SDI regions, and four continents. Decomposition analysis, frontier analysis, and forecasting models were employed to explore changes in these indicators and their influencing factors.

RESULTS

In 2021, CKD attributable to low physical activity (LPA) resulted in 913,070 [95% UI: 348,170-1,619,770] DALYs and 40,920 [95% UI: 16,170-72,560] deaths globally, both of which were higher than those reported in 1990. The AOSD increased from 9.63 (95% UI: 3.73-17.02) to 10.81 (95% UI: 4.14-19.18) per 100,000, with an EAPC of 0.42 (95% CI: 0.35-0.48). The ASMR increased from 0.42 (95% UI: 0.17-0.74) to 0.50 (95% UI: 0.20-0.90) per 100,000, with an EAPC of 0.65 (95% CI: 0.57-0.73). The burden was greater among females, with more rapid increases in the ASDR and ASMR. The Americas and high-SDI regions presented the greatest growth in DALY and mortality rates.

CONCLUSIONS

The burden of CKD attributable to low physical activity (LPA) has increased significantly, particularly in low-SDI regions, women, and elderly individuals. The findings highlight the importance of promoting physical activity and implementing early interventions to inform public health policies.

CLINICAL TRIAL NUMBER

Not applicable.

The association between the cardiac metabolic index and rapid kidney function decline and CKD in individuals with different glucose metabolism statuses: results from the China health and retirement longitudinal study

BACKGROUND

The Cardiometabolic Index (CMI) is a new measure that combines fat distribution and lipid profiles. However, its relationship with rapid decline in renal function and the chronic kidney disease (CKD), especially in individuals with varying glucose metabolism, is still unclear.

METHOD

This study included 3,485 participants aged 45 and above from the China Longitudinal Study on Health and Retirement (CHARLS), with baseline assessments in 2011-2012 and follow-ups in 2015 and 2018. Participants were grouped into four categories (Q1-Q4) based on baseline CMI levels. The primary outcome was rapid decline in renal function, with CKD events also observed. Multivariable logistic models and restricted cubic spline (RCS) analysis were used to explore the relationship between baseline CMI levels and the risk of kidney disease in individuals with different glucose metabolism statuses. Nine machine learning models were developed using baseline CMI to validate its predictive ability for kidney disease risk. Finally, mediation causal analysis was conducted to examine whether the development of diabetes in the non-diabetic population serves as an important mediator in the relationship between CMI and kidney disease.

RESULTS

During the follow-up period, a total of 173 participants (4.96%) experienced rapid decline in renal function, and 87 participants (2.50%) developed CKD. With increasing baseline CMI levels, the risk of rapid decline in renal function and CKD significantly increased. Among the various machine learning models for predicting kidney disease, logistic regression performed excellently, with AUCs exceeding 0.6, indicating the strong predictive ability of baseline CMI. For the primary outcome, multivariable logistic regression analysis showed that, in all participants, as well as in the normal glucose regulation (NGR) group and the prediabetes (Pre-DM) group, the incidence of rapid decline in renal function significantly increased across different CMI groups (P < 0.05), with trend RR values of 1.285(1.076,1.536), 1.308 (1.015, 1.685) and 1.566 (1.207, 2.031), respectively. However, this association was not observed in patients with diabetes (P for trend > 0.05). RCS analysis further indicated that higher baseline CMI levels were associated with a greater risk of rapid decline in renal function in all participants and in the non-diabetic population. A similar trend was observed for CKD. Finally, mediation causal analysis showed that the development of new-onset diabetes in the non-diabetic population may not be an important mediator in the relationship between CMI and kidney disease.

CONCLUSION

Higher baseline CMI levels were significantly linked to rapid decline in renal function and CKD in middle-aged and elderly individuals, with the relationship varying by glucose metabolism status. CMI may serve as a useful indicator for predicting kidney disease risk, especially in non-diabetic population.

Exercise combined with metformin ameliorates diabetic kidney disease by increasing renal autophagy and reducing oxidative stress in rats with high-fat diet and streptozotocin induced diabetes

Diabetic kidney disease (DKD) is one of the common and serious complications of type 2 diabetes mellitus (T2DM). Metformin is commonly prescribed for the treatment of T2DM, while exercise is frequently recommended as adjunctive therapy. However, the therapeutic efficacy and molecular etiology of combined therapy with exercise and metformin in DKD remain to be elucidated. The present study therefore aimed to investigate the therapeutic effects and mechanisms underlying the combined effects of exercise and metformin on DKD. A rat model of T2DM was constructed by administering a high-fat diet and intraperitoneal injections of streptozotocin (30 mg/kg) for 6 weeks. The rats with T2DM exhibited reduced autophagic flux, increased oxidative stress, and morphological and structural lesions in the kidneys, compared to those of normal rats in the control group. The combination of exercise and metformin alleviated DKD, indicated by the elevation of renal autophagic flux, and a reduction in oxidative stress, renal fibrosis, and histopathological damage to the kidneys. Our findings suggested that exercise combined with metformin has a therapeutic role in DKD, and the study serves as a valuable reference for future research on the treatment of DKD.

[Impact of APA on functional performance in elderly sarcopenic patients]

Adapted physical activity (APA) is an important means of preventing sarcopenia. Our aim was to evaluate the impact on functional performance of a multi-component program entitled "circuit gym", including the use of muscle-strengthening machines specially designed for seniors. This was a single-center interventional study combining endurance, machine resistance and balance exercises, lasting three months. We included 95 patients (mean age 82.5 years, 59% women). A median increase of two points in the Short Physical Performance Battery was observed at the end of the program (p<0.0001), as well as a significant improvement in walking speed, chair raising and Timed Up and Go. This study demonstrated a functional improvement in elderly sarcopenic individuals at three months associated with multicomponent adapted physical activity.

Association between cardiometabolic index and albuminuria: Evidence from NHANES 2017-2020

INTRODUCTION

Albuminuria is a crucial marker of kidney damage and serves as an early indicator of the risk for chronic kidney disease (CKD). Recent studies have suggested that the cardiometabolic index (CMI), could be valuable for screening renal insufficiency. However, the relationship between CMI and albuminuria remains underexplored. Therefore, the aim of this study was to investigate the association between CMI and albuminuria, with the goal of providing new insights for the clinical diagnosis, assessment, and early intervention of kidney disease.

METHODS

The National Health and Nutrition Examination Survey (NHANES) for the period between 2017-2020 provided the data for this cross-sectional investigation. Triglyceride (TG) (mmol/L)/High density lipid-cholesterol (HDL-C) (mmol/L) ×  Waist height ratio (WHtR) was the formula used for calculating CMI. Using multifactorial logistic regression, the independent connection between albuminuria and CMI was investigated. The threshold effect was determined by means of a two-stage linear regression model. Additionally, subgroup analysis and interaction tests were carried out.

RESULTS

A total of 3,339 participants were included, and 12.38% of them had albuminuria. As the CMI quartiles grew (quartile 1: 7.78%, quartile 2: 13.43%, quartile 3: 12.93%, quartile 4: 17.01%), so did the probability of albuminuria. The results of adjusted model 3 showed that a greater probability of albuminuria prevalence was strongly correlated with CMI (OR =  2.26, 95% CI: 1.58-3.23). This association held true for all subgroups (all P for trend >  0.05). Furthermore, with a two-stage linear regression model with an inflection point of 0.92, we discovered a nonlinear relationship between CMI and albuminuria.

CONCLUSIONS

Our findings indicate that CMI levels are significantly associated with the risk of albuminuria prevalence, suggesting that CMI could serve as a valuable biomarker for assessing the risk of albuminuria.

The relationship between physical exercise and psychological capital in college students: the mediating role of perceived social support and self-control

BACKGROUND

The mental health of college students significantly impacts their life, academic performance, and even employment prospects. Research indicates that physical exercise can promote mental health, but the pathways of its influence require further exploration. This study investigates the relationship between physical exercise and psychological capital in college students, focusing on the mediating roles of perceived social support and self-control.

OBJECTIVES

This study seeks to investigate the relationship between physical exercise and psychological capital among university students, with a further in-depth analysis of the mediating roles played by perceived social support and self-control within this dynamic.

METHODS

Using cluster sampling, we surveyed 898 college students from five universities in Xinxiang, Henan Province, employing the Physical Activity Rating Scale (PARS-3), the Perceived Social Support Scale (PSSS), the Revised Self-Control Scale (SCS), and the Psychological Capital Questionnaire (PCQ). Data were analyzed using SPSS 26.0 and Amos 23.0, and common method bias was tested using Harman's single-factor test. The significance of the mediation effects was tested using the bootstrap sampling method.

RESULTS

(1) Physical exercise is significantly correlated with psychological capital (r = 0.786, p < 0.01); (2) Perceived social support and self-control mediate the relationship between physical exercise and psychological capital; (3) The mediation effect consists of two indirect effects: physical exercise → perceived social support → psychological capital (β = 0.404, 95% CI: 0.336-0.473) and physical exercise → self-control → psychological capital (β = 0.158, 95% CI: 0.067-0.242).

CONCLUSION

Physical exercise can directly enhance the psychological capital of college students and can indirectly influence psychological capital through perceived social support or self-control. The mediating effect of perceived social support is stronger than that of self-control.

Effect of an intensive lifestyle intervention on cystatin C-based kidney function in adults with overweight and obesity: From the PREDIMED-Plus trial

BACKGROUND

Large-scale trials evaluating a multicomponent lifestyle intervention aimed at weight loss on kidney function are lacking.

METHODS

This was a post hoc analysis of the "PREvención con DIeta MEDiterránea-Plus" (PREDIMED-Plus) randomized controlled trial, including patients with overweight/obesity and metabolic syndrome, measured cystatin C and creatinine. Participants were randomly assigned (1:1) to an intensive weight loss lifestyle intervention (intervention group [IG]) consisting of an energy-restricted Mediterranean diet (MedDiet), physical activity promotion and behavioral support, or a control group (CG) receiving ad libitum MedDiet recommendations. The primary outcome was between-group differences in cystatin C-based kidney function (cystatin C-based estimated glomerular filtration rate-eGFRcys-and combined cystatin C-creatinine-based eGFR-eGFRcr-cys) change from baseline to 12 and 36 months. Secondary outcomes included between-group differences in creatinine-based eGFR (eGFRcr) and urinary albumin-to-creatinine ratio (UACR) change and the predictive capacity of these formulas at baseline for new-onset chronic kidney disease (CKD).

RESULTS

A total of 1909 participants (65 ± 5 years, 54% men) were included. Twelve-month decline in eGFRcys, eGFRcr-cys, and eGFRcr was greater in the CG compared to the IG, with between-group differences of -1.77 mL/min/1.73 m2 [95% confidence interval -2.92 to -0.63], -1.37 [-2.22 to -0.53], and -0.91 [-1.74 to -0.71], respectively. At 36 months, the decline in eGFRcr-cys and eGFRcr was greater in the CG. No between-group differences in UACR were found. Significant adjusted areas under the curve for baseline eGFRcys and eGFRcr-cys were observed for incident CKD at 36 months, which were similar to those for eGFRcr and UACR.

CONCLUSIONS

In older adults with overweight/obesity and metabolic syndrome, the PREDIMED-Plus intervention may be an optimal approach to preserve kidney function.

Association between chronic kidney disease and oxidative balance score: National Health and Nutrition Examination Survey (NHANES) 2005-2018

Background

The oxidative balance score (OBS) is a comprehensive concept that includes 16 dietary components and four lifestyle factors to assess an individual's exposure to pro-oxidants and antioxidants. This study aims to explore the relationship between OBS and the risk of chronic kidney disease (CKD).

Methods

This cross-sectional study included nationally representative National Health and Nutrition Examination Survey (NHANES) participants aged 18 and above from 2005 to 2018. The OBS, a novel concept derived from multiple dietary (pro-oxidant and antioxidant nutrients) and lifestyle exposures (including smoking, alcohol consumption, obesity, and physical activity), serves as a useful tool for assessing an individual's oxidative stress status. The continuous variable OBS was converted into categorical variables by quartiles. Covariates included age, gender, race, education level, marital status, poverty-income ratio, sleep duration, depression, hypertension, diabetes, hyperlipidemia, cardiovascular disease, use of hypoglycemic medications, and use of antihypertensive medications. The relationship between OBS and CKD was explored using multiple logistic regression analysis and restricted cubic spline models. Additionally, subgroup analyses, interaction tests, and sensitivity analyses were conducted to validate the stability of the results.

Results

A total of 25,118 NHANES participants were included in this study. The weighted prevalence of CKD was 14.97%. In the fully adjusted model, compared to the lowest OBS quartile, participants in the highest quartile had a 26% reduced risk of CKD (OR = 0.74, 95%CI: 0.63-0.87, p < 0.001). In restricted cubic spline regression, there was a linear association between OBS and CKD. The results of subgroup analysis and sensitivity analysis remain consistent. A significant interaction was found in the stratified analysis by age group (p for interaction = 0.012), suggesting that individuals older than 60 years may benefit more significantly from an increase in OBS scores compared to those aged 60 years or younger.

Conclusion

This study demonstrates that higher OBS is associated with a lower risk of CKD, particularly among the elderly population, providing innovative insights and preliminary evidence for the development of preventive strategies against CKD.

Comparative efficacy of exercise modalities for general risk factors, renal function, and physical function in non-dialysis chronic kidney disease patients: a systematic review and network meta-analysis

BACKGROUND

Exercise therapy can effectively manage chronic kidney disease (CKD) risk factors and improve renal function and physical fitness, but the challenge lies in choosing the right exercise type tailored to patients' condition.

METHODS

An electronic search of databases including PubMed, The Cochrane Library, EMBASE, Web of Science, VIP, WanFang, and CNKI was performed. The random effects model was used. Mean difference was employed as the effect size for continuous variables, with 95% confidence interval (CI) provided.

RESULTS

A total of 36 RCTs were included in this study. Compared to conventional therapy (CT), the combination of three exercise therapies with CT resulted in notable benefits in enhancing six minutes walk test (6MWT) capacity, 24-h urinary protein quantity (24hUTP), systolic blood pressure (SBP), diastolic blood pressure (DBP). Resistance exercise therapy (RT) + CT were more effective than CT to reduce serum creatinine (Scr), body mass index (BMI), and hemoglobin A1c (HbA1c) and improve estimated glomerular filtration rate (eGFR). In terms of improving peak oxygen uptake (VO2 peak), only two exercise modalities were involved, aerobic exercise therapy (AT) and combined (Resistance-Aerobic) exercise therapy (CBT), both of which were more efficacious than CT. The efficacy ranking overall demonstrated clear benefits for RT in enhancing eGFR and 6MWT, decreasing Scr, BMI, SBP, DBP, and HbA1c, while AT was more suitable for boosting VO2 peak, and CBT had greater potential for reducing 24hUTP.

CONSLUSIONS

Exercise therapy combined with CT offers significant advantages over CT in many cases, but no single exercise modality is universally effective for all indicators.

Tailored exercise with telehealth monitoring improves adherence and global health in kidney transplant recipients

Introduction

Tailored exercise prescription is a crucial intervention for kidney transplant recipients (KTRs). This longitudinal study investigates the impact on long-term effectiveness of exercise prescriptions over one year follow-up, implementing telehealth tools for exercise administration and adherence monitoring.

Materials and methods

KTRs were evaluated with clinical assessments including body composition, blood and urinary parameters, physical performance and quality of life at baseline (T0), after six (T6) and twelve (T12) months. The adherence to prescribed exercise training was monitored via video call interviews until T6 when the sample was divided into a group monitored via wearables (WG) and a group continuing video calls (VG) until T12.

Results

Twenty-six KTRs completed the study. No changes in body composition and kidney function were reported. KTRs showed an improvement in lipid profile, systolic blood pressure, cardiorespiratory fitness and quality of life. WG showed no clinical differences compared to VG except for reported higher quality of life.

Discussion

A good adherence to the exercise prescription was obtained with both monitoring methods (232 vs 253 min/week). This study reinforces the inclusion exercise training for KTRs to enhance physical fitness and reduce cardiovascular risk factors. These results emphasize the role of telehealth monitoring methods as motivators for adherence to long-term exercise prescriptions.

Functional Foods and Adapted Physical Activity as New Adjuvant Therapy for Chronic Kidney Disease Patients

BACKGROUND

Chronic kidney disease (CKD) will become the fifth leading cause of death in the world by 2040. It is fundamental to prevent and treat this pathology to reduce its impact on national health costs. This trial's aim is to evaluate the effects induced by a combination of consumed functional foods (FFs) with adapted physical activity (APA) on the progression of CKD-related comorbidities.

METHODS

The study lasted 12 weeks. We divided 40 CKD patients into four groups: mixed (FF + APA), APA, FF and control group (usual care). The FFs were characterized by their total antioxidant capacity and antiradical activity. The APA was performed though an online training protocol, three times per week, 1 h each session.

RESULTS

At the end of the study, we observed, in the mixed group, a decrease in azotemia (p = 0.0272), diastolic blood pressure (p = 0.0169), and C-reactive protein (p = 0.0313), with increases in the FORD test (p = 0.0203) and fat free mass (p = 0.0258). The APA group showed a reduction in total cholesterol (p = 0.0039).

CONCLUSIONS

The combination of FFs and APA can help counteract several CKD-related comorbidities, such as arterial hypertension, dyslipidemia and uremic sarcopenia, and improve the CKD patients' quality of life.

Pathophysiology of Physical Exercise in Kidney Patients: Unveiling New Players - The Role of Myokines

BACKGROUND

Chronic kidney disease (CKD) is a progressive systemic condition characterized by numerous complications. Among these, alterations in skeletal muscle physiology, such as sarcopenia, are particularly significant, as they are associated with poor outcomes and reduced quality of life.

SUMMARY

Various interventions, including pharmacological approaches and lifestyle modifications have been investigated to slow CKD progression and prevent or treat its complications. Physical exercise, in particular, has emerged as a promising intervention with multiple beneficial effects. These include improvements in physical functioning, increased muscle mass, modulation of metabolic abnormalities, and reduced cardiovascular risk. However, the pathophysiology of physical exercise in patients with kidney disease is complex and remains only partially understood. A crucial advancement in understanding this phenomenon has been the identification of myokines - molecules expressed and released by skeletal muscle in response to physical activity. These myokines can exert both paracrine and systemic effects, influencing not only skeletal muscle physiology but also other processes such as energy metabolism and lipid regulation.

KEY MESSAGES

The interplay among skeletal muscle, physical activity, and myokines may act as a pivotal regulator in various physiological processes, including aging, as well as in pathological conditions like cachexia and sarcopenia, frequently observed in CKD patients at different stages, including patients on dialysis. Despite the potential importance of this relationship, only a limited number of studies have explored the relationship between exercise and myokine, and the effect of this interaction on experimental models or individuals with kidney disease. In the following sections, we review and discuss this topic.