Modifiable Lifestyle Factors for Primary Prevention of CKD: A Systematic Review and Meta-Analysis

Dietary protein and muscle wasting in chronic kidney disease: new insights

PURPOSE OF REVIEW

Muscle wasting is an important health problem in chronic kidney disease (CKD) patients. Protein restriction in the diet can be one of the main causes of muscle wasting in this population. In this review, we aimed to investigate the relationship between dietary protein intake and muscle wasting in CKD patients according to recent literature.

RECENT FINDINGS

The one of the main mechanisms responsible for the muscle wasting is the disturbances in skeletal muscle protein turnover. Muscle wasting primarily occurs when the rates of muscle protein breakdown exceed the muscle protein synthesis. Dietary protein intake represents an important role by causing a potent anabolic stimulus resulting a positive muscle protein balance. Compared to studies made in healthy populations, there are very limited studies in the literature about the relationship between dietary protein intake and muscle wasting in the CKD population. Majority of the studies showed that a more liberal protein intake is beneficial for muscle wasting in especially advanced CKD and hemodialysis population.

SUMMARY

Although evaluating muscle wasting in CKD patients, the amount of protein in the diet of patients should also be reviewed. Although excessive protein intake has some negative consequences on this patient group, a more liberated dietary protein intake should be taken into account in this patient group with muscle wasting and especially in dialysis patients.

Habitual Fish Oil Supplementation and Incident Chronic Kidney Disease in the UK Biobank

BACKGROUND

To explore the relation of habitual fish oil use with the risk of chronic kidney diseases (CKD).

METHODS

408,023 participants (54.2% female) without prior CKD and with completed information regarding their consumption of major food groups and fish oil in the UK Biobank were enrolled. Fish oil use and dietary intakes were assessed by touch screen questionnaire and food frequency questionnaire, respectively. Incident CKD was recorded from hospital inpatient records.

RESULTS

At baseline, 128,843 (31.6%) participants reported taking fish oil supplements. During a median follow-up period of 12.0 years, a total of 10,782 (2.6%) participants developed CKD. With adjustments for important confounders, habitual fish oil use was associated with a significantly lower hazard of incident CKD (hazard ratio [HR], 0.90; 95% confidence interval [CI], 0.87-0.95), compared with non-use. Consistently, participants reporting ≥2 servings/week of oily fish (HR, 0.86; 95% CI, 0.79-0.94) and nonoily fish (HR, 0.86; 95% CI, 0.77-0.97) consumption had a lower hazard of incident CKD compared to those reporting no consumption ever. Additionally, among the 97,914 participants with data on plasma fatty acid, there were significant inverse relationships of plasma omega-3 polyunsaturated fatty acid (PUFA) (per SD increment, HR, 0.89, 95% CI, 0.84-0.94) and eicosatetraenoic acid (per SD increment, HR, 0.91, 95% CI, 0.87-0.96) with incident CKD.

CONCLUSIONS

Habitual fish oil use was associated with a lower hazard of CKD, which was further confirmed by the consistent inverse relations between fish consumption and circulating omega-3 PUFA concentration with incident CKD.

Self-rated health and the risk of incident chronic kidney disease: a community‐based Korean study

BACKGROUND

The relationship between self-rated health (SRH) and the development of incident chronic kidney disease (CKD) has not been explored in the general population.

METHODS

We reviewed the data of 7027 participants in the Ansung-Ansan cohort study. SRH was categorized as poor, fair, or good, and the outcome was the development of CKD, defined as the first event of an estimated glomerular filtration rate < 60 mL/min/1.73 m², at least twice during the follow-up period. Hazard ratios (HRs) and confidence intervals (CIs) were calculated using Cox proportional hazards regression analysis.

RESULTS

Over a mean follow-up duration of 11.9 years, 951 participants (13.5%) developed CKD. Compared with poor self-rated health, the HR (95% CI) of fair self-rated health for incident CKD development was 0.771 (0.657-0.905; P = 0.001), whereas that of good self-rated health was 0.795 (0.676-0.935; P = 0.006). However, the renal hazard of good self-rated health did not differ from that of fair self-rated health. In the fully adjusted model, the HR (95% CI) of poor self-rated health compared to non-poor self-rated health for incident CKD was 1.278 (1.114-1.465, P < 0.001). Old age, smoking, cardiovascular disease, diabetes, hypertension, impaired sleep, and high levels of C-reactive protein and white blood cell counts were associated with increased odds of poor self-rated health, whereas male sex, college graduate level of education, and alcohol consumption were associated with decreased odds of poor self-rated health.

CONCLUSION

Poor self-rated health is independently associated with CKD development. Therefore, the early detection of potential CKD patients through a brief questionnaire assessment may help control the incidence of CKD.

Prevention of cardiorenal damage: importance of albuminuria

Chronic kidney disease (CKD) is projected to become a leading global cause of death by 2040, and its early detection is critical for effective and timely management. The current definition of CKD identifies only advanced stages, when kidney injury has already destroyed &gt;50% of functioning kidney mass as reflected by an estimated glomerular filtration rate &lt;60 mL/min/1.73 m2 or a urinary albumin/creatinine ratio &gt;six-fold higher than physiological levels (i.e. &gt; 30 mg/g). An elevated urinary albumin-excretion rate is a known early predictor of future cardiovascular events. There is thus a ‘blind spot’ in the detection of CKD, when kidney injury is present but is undetectable by current diagnostic criteria, and no intervention is made before renal and cardiovascular damage occurs. The present review discusses the CKD ‘blind spot’ concept and how it may facilitate a holistic approach to CKD and cardiovascular disease prevention and implement the call for albuminuria screening implicit in current guidelines. Cardiorenal risk associated with albuminuria in the high-normal range, novel genetic and biochemical markers of elevated cardiorenal risk, and the role of heart and kidney protective drugs evaluated in recent clinical trials are also discussed. As albuminuria is a major risk factor for cardiovascular and renal disease, starting from levels not yet considered in the definition of CKD, the implementation of opportunistic or systematic albuminuria screening and therapy, possibly complemented with novel early biomarkers, has the potential to improve cardiorenal outcomes and mitigate the dismal 2040 projections for CKD and related cardiovascular burden.

Treatment of Chronic Kidney Disease: Moving Forward

Chronic kidney disease (CKD) affects ~10% of the adult population [...].

Nutrition and quality of life in chronic kidney disease patients: a practical approach for salt restriction

The clinical practice guidelines (CPGs) for nutrition in chronic kidney disease (CKD) were updated after 20 years from the previous guidelines by the Kidney Disease Outcomes Quality Initiative (KDOQI). During this period, the severity of CKD was defined by eGFR and albuminuria by the organization Kidney Disease: Improving Global Outcomes (KDIGO). Main risk factors for CKD such as hypertension, hyperlipidemia, obesity, metabolic syndrome, and diabetes mellitus are closely related to lifestyle. Nutritional management is important to prevent and retard the progression of CKD. Members of the International Society of Renal Nutrition and Metabolism (ISRNM) reviewed the KDOQI CPG draft. ISRNM is an international scientific society comprising members of multiple subspecialties. ISRNM proposed the medical term protein-energy wasting (PEW), which is a keyword in renal nutrition. The prevalence of PEW among dialysis patients is high. The success of dietary therapy depends on adherence to the diet. It has to be palatable, otherwise eating habits will not change. To prevent the development and progression of CKD and PEW, regular consultation with an expert dietitian is required, especially regarding salt and protein restriction. Our cluster-randomized trial showed that intervention by a dietician was effective at retarding the progression of stage 3 CKD. In this review, I focus on salt (sodium) restriction and introduce tips for salt restriction and Japanese kidney-friendly recipes. Due to the lack of randomized controlled trials, nutritional management of CKD inevitably relies on expert opinion. In this regard, well-designed observational studies are needed. Too strict salt restriction may decrease quality of life and result in PEW.

A prediction model with lifestyle factors improves the predictive ability for renal replacement therapy: a cohort of 442 714 Asian adults

Background

There are limited renal replacement therapy (RRT) prediction models with good performance in the general population. We developed a model that includes lifestyle factors to improve predictive ability for RRT in the population at large.

Methods

We used data collected between 1996 and 2017 from a medical screening in a cohort comprising 442 714 participants aged 20 years or over. After a median follow-up of 13 years, we identified 2212 individuals with end-stage renal disease (RRT, n: 2091; kidney transplantation, n: 121). We built three models for comparison: model 1: basic model, Kidney Failure Risk Equation with four variables (age, sex, estimated glomerular filtration rate and proteinuria); model 2: basic model + medical history + lifestyle risk factors; and model 3: model 2 + all significant clinical variables. We used the Cox proportional hazards model to construct a points-based model and applied the C statistic.

Results

Adding lifestyle factors to the basic model, the C statistic improved in model 2 from 0.91 to 0.94 (95% confidence interval: 0.94, 0.95). Model 3 showed even better C statistic value i.e., 0.95 (0.95, 0.96). With a cut-off score of 33, model 3 identified 3% of individuals with RRT risk in 10 years. This model detected over half of individuals progressing to RRT, which was higher than the sensitivity of cohort participants with stage 3 or higher chronic kidney disease (0.53 versus 0.48).

Conclusions

Our prediction model including medical history and lifestyle factors improved the predictive ability for end-stage renal disease in the general population in addition to chronic kidney disease population.

The effect of regular aerobic exercise on renal function in patients with CKD: A systematic review and meta-analysis

Objective: To evaluate the effect of regular aerobic exercise on the improvement of renal function in patients with chronic kidney disease through meta-analysis and to provide targeted exercise recommendations for patients with CKD. Methods: PubMed, Web of Science, EBSCO, China National Knowledge Infrastructure (CNKI), and other databases were searched, and randomized controlled trials on the effects of regular aerobic exercise on renal function-related indexes in patients with CKD were collected according to the inclusion and exclusion criteria. The methodological quality of the included literature was evaluated using the Cochrane evaluation tool second generation, and statistical analysis was performed using R analysis software. Results: A total of 12 randomized controlled trials (RCTs) with a total of patients with CKD were included, and the results of the meta-analysis showed that regular aerobic exercise significantly improved the estimated glomerular filtration rate SMD = 0.65, 95% CI [0.30, 1.00], serum creatinine SMD = -0.63, 95% CI [-0.86, -0.40], 24-h urine protein volume in patients with CKD SMD = -0.41, 95% CI [-0.70, -0.11], and serum urea nitrogen SMD = -0.66, 95% CI [-1.20, -0.12]. Single exercise session longer than 30 min significantly improved the estimated glomerular filtration rate in CKD patients (p < 0.01), and walking and running as exercise modalities significantly improved CKD patients' SCr levels were significantly improved by walking and running as exercise modalities (p < 0.05), and the improvement effect was not significant when cycling was selected as an exercise modality. Conclusion: Regular aerobic exercise has a significant effect on the estimated glomerular filtration rate, serum creatinine, 24-h urine protein amount, and blood urea nitrogen in CKD patients. Aerobic exercise with a single exercise duration longer than 30 min has a more significant effect on the estimated glomerular filtration rate, and aerobic exercise by walking or running can more effectively improve the serum creatinine in CKD patients.

Xenobiotics Delivered by Electronic Nicotine Delivery Systems: Potential Cellular and Molecular Mechanisms on the Pathogenesis of Chronic Kidney Disease

Chronic kidney disease (CKD) is characterized as sustained damage to the renal parenchyma, leading to impaired renal functions and gradually progressing to end-stage renal disease (ESRD). Diabetes mellitus (DM) and arterial hypertension (AH) are underlying diseases of CKD. Genetic background, lifestyle, and xenobiotic exposures can favor CKD onset and trigger its underlying diseases. Cigarette smoking (CS) is a known modified risk factor for CKD. Compounds from tobacco combustion act through multi-mediated mechanisms that impair renal function. Electronic nicotine delivery systems (ENDS) consumption, such as e-cigarettes and heated tobacco devices, is growing worldwide. ENDS release mainly nicotine, humectants, and flavorings, which generate several byproducts when heated, including volatile organic compounds and ultrafine particles. The toxicity assessment of these products is emerging in human and experimental studies, but data are yet incipient to achieve truthful conclusions about their safety. To build up the knowledge about the effect of currently employed ENDS on the pathogenesis of CKD, cellular and molecular mechanisms of ENDS xenobiotic on DM, AH, and kidney functions were reviewed. Unraveling the toxic mechanisms of action and endpoints of ENDS exposures will contribute to the risk assessment and implementation of proper health and regulatory interventions.

Dietary vitamin E and tocopherol isoforms and incident chronic kidney disease: A 30-y follow-up study from young adulthood to midlife

BACKGROUND

The relationship of dietary vitamin E intake with incident chronic kidney disease (CKD) was not clear as yet. We aimed to examine the associations of dietary total vitamin E and tocopherol isoforms intakes with incident CKD in a 30-year follow-up study from young adulthood to midlife.

METHODS

A total of 4038 American adults aged 18-30 years and without reduced estimated glomerular filtration rate (eGFR) were enrolled from Coronary Artery Risk Development in Young Adults study. Diet was evaluated by a validated dietary-history questionnaire at baseline, and after 7 and 20 years later. The study outcome was incident CKD, defined as an eGFR<60 mL/min/1.73 m² or a urinary albumin to creatinine ratio ≥30 mg/g.

RESULTS

During a 30-year follow-up, 642 (15.9%) participants developed incident CKD. Overall, there was a L-shaped relationship between dietary total vitamin E intake and incident CKD (P for non-linearity<0.001). When total vitamin E intake was assessed as quartiles, compared with those in the first quartile (<4.35 mg α-TE/1000 kcal), the adjusted HRs (95%CI) of incident CKD for participants in the fourth quartile (≥9.61 mg α-TE/1000 kcal) was 0.55 (0.40, 0.75). Moreover, higher intakes of beta-tocopherol and gamma-tocopherol were significantly associated with a lower incident CKD. Higher intake of delta-tocopherol was significantly related to a higher incident CKD. And there was no obvious association of alpha-tocopherol intake with incident CKD.

CONCLUSIONS

There were inverse associations of total vitamin E, beta-tocopherol and gamma-tocopherol intakes, a positive association of delta-tocopherol intake, and no obvious association of alpha-tocopherol intake, with incident CKD among American adults.

Construction of the health risk assessment index system for assessing the chronic diseases based on the general health

Aims

This study aimed to construct a standardized health risk assessment index system (HRAIS) under the guidance of general health and facilitate the family doctors to carry out chronic disease management.

Methods

Available chronic disease surveillance systems and indexes were reviewed to identify potential indexes. The Delphi method was performed to establish the HRAIS, and the analytic hierarchy process was used to calculate the index weight.

Results

HRAIS included four first-level indexes and 38 second-level indexes. The authority coefficient was 0.86. The Kendall's W for the two rounds of Delphi consultation were 0.202 and 0.210 (p < 0.001). The weights of the first-level indexes from high to low were physiological health (0.409), psychosocial health (0.290), health-related behaviors (0.205), and environment (0.097). Thus, HRAIS is a multi-dimension and multi-index tool, which can be used as a guideline for family doctors in early screening, early intervention, and classified management of main chronic diseases.

Bidirectional relations between depression symptoms and chronic kidney disease

BACKGROUND

Depression and chronic kidney disease (CKD) often coexist. However, both the relations of depression with CKD development and CKD with depression risk were still elusive. We aimed to investigate the bidirectional relations between renal function and depression in a cohort of young and middle-aged adults.

METHODS

Using data from the Coronary Artery Risk Development in Young Adults study, the analysis of depressive symptoms and incident CKD (analysis 1) was performed in 3,731 participants without CKD, and the analysis of renal function and incident depression (analysis 2) was performed in 2,994 participants without depression. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale (-CES-D), and depression was defined as CES-D scores ≥16 or self-reported history of depression or antidepressant medication use. CKD was defined as estimated glomerular filtration rate <60 ml/min/1.73 m² or urinary albumin to creatinine ratio ≥30 mg/g.

RESULTS

In analysis 1, 485 participants developed incident CKD during 61,202 person-years of follow-up, and CES-D scores (≥16 vs. <16; adjusted HR, 1.28; 95% CI, 1.04 to 1.59) were significant positive associated with incident CKD. In analysis 2, 1,029 participants developed incident depression during 42,927 person-years of follow-up, and CKD was significantly associated with a 36% increased risk of incident depression compared to non-CKD (HR, 1.36; 95% CI, 1.05 to 1.76).

LIMITATIONS

Depressive symptoms were only assessed using CES-D score, which is not the gold standard for the clinical diagnosis of depression.

CONCLUSIONS

This prospective cohort study monitored over 20 years indicated a bidirectional association between depression and CKD.

Low-protein diet is inversely related to the incidence of chronic kidney disease in middle-aged and older adults: results from a community-based prospective cohort study

PURPOSE

Dietary protein intake can modulate renal health. However, the effect of dietary protein restriction on kidney function in the general population remains unclear. This study aimed to examine the association between total protein intake and new-onset chronic kidney disease (CKD) in Korean adults.

METHODS

We included 7339 participants from the Korean Genome and Epidemiology Study. Participants were divided into low-protein diet (LPD, < 0.8 g/kg/day), normal-protein diet (NPD, 0.8-1.3 g/kg/day), and high-protein diet (HPD, > 1.3 g/kg/day) groups. New-onset CKD was defined as two consecutive events of estimated glomerular filtration rate < 60 mL/min/1.73 m². Multivariable Cox hazard regression analysis was conducted to examine the association of total protein intake with new-onset CKD. Subgroup analyses according to diabetes mellitus (DM) status were performed. We performed the same analyses by dividing participants into total protein, plant protein, and animal protein intake tertiles.

RESULTS

During a median follow-up of 13.7 years, 633 (8.7%) participants newly developed CKD. The fully adjusted hazard ratios (HR) with 95% confidence interval (CI) for incident CKD of the LPD and HPD groups compared with the NPD group were 1.49 (1.18-1.87) and 0.63 (0.45-0.87), respectively. The HR (95% CI) of the highest tertile group of plant protein intake for incident CKD was 0.72 (0.54-0.93), compared with that of the lowest tertile group. Similar trends were observed only in the non-DM subgroup, not in the DM subgroup.

CONCLUSION

Protein intake, especially plant proteins, was negatively associated with the incidence of new-onset CKD in middle-aged and older Korean adults.

A methodologic survey on use of the GRADE approach in evidence syntheses published in high-impact factor urology and nephrology journals

Background

To identify and describe the use of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach for rating the certainty of systematic reviews (SRs) evidence published in urology and nephrology journals.

Methods

SRs that were published in the top ten "urology and nephrology" journals with the highest impact factor according to the 2020 Journal Citation Reports (covering 2016–2020) were systematically searched and evaluated using the GRADE approach.

Results

A total of 445 SRs were researched. Sixty SRs of randomized control trials (RCTs) and/or non-randomized studies (NRSs) were evaluated using the GRADE approach. Forty-nine SRs (11%) rated the outcome-specific certainty of evidence (n = 29 in 2019–2020). We identified 811 certainty of evidence outcome ratings (n = 544 RCT ratings) as follows: very low (33.0%); low (32.1%); moderate (24.5%); and high (10.4%). Very low and high certainty of evidence ratings accounted for 55.0% and 0.4% of ratings in SRs of NRSs compared to 23.0% and 15.3% in SRs of RCTs. The certainty of evidence for RCTs and NRSs was downgraded most often for risk of bias and imprecision.

Conclusions

We recommend increased emphasis on acceptance of the GRADE approach, as well as optimal use of the GRADE approach, in the synthesis of urinary tract evidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01701-x.

Management of Metabolic Acidosis in Chronic Kidney Disease: Past, Present, and Future Direction

Chronic kidney disease (CKD) is a major global epidemic associated with increased morbidity and mortality. Despite the effectiveness of kidney protection strategies of hypertension, diabetes, and lipid control and use of newer hypoglycemic agents and anti-angiotensin II drugs, the nephropathy in CKD continues unabated toward irreversible kidney failure. Thus, interventions targeting modifiable risk factors in CKD such as metabolic acidosis (MA) are needed. Acid reduction with sodium-based alkali has been shown to be an effective kidney-protection strategy for patients with CKD and reduced glomerular filtration rate (GFR). Small-scale studies reveal diets emphasizing ingestion of plant-sourced over animal-sourced protein reduce dietary acid, improve MA, and slow further nephropathy progression in patients with CKD and reduced GFR. Additionally, veverimer, an investigational, nonabsorbed polymer that binds and removes gastrointestinal hydrochloric acid, is being developed as a novel treatment for MA. As further studies define how to best use these interventions for kidney protection, clinicians must become aware of their potential utility in the management of patients with CKD. The aim of the present review is to explore the various intervention strategies that increase or normalize serum [HCO₃^-] in patients with CKD-associated MA or low normal serum [HCO₃^-] that may further slow progression of CKD.

Living Well With Kidney Disease and Effective Symptom Management: Consensus Conference Proceedings

Chronic kidney disease (CKD) confers a high burden of uremic symptoms that may be underrecognized, underdiagnosed, and undertreated. Unpleasant symptoms, such as CKD-associated pruritus and emotional/psychological distress, often occur within symptom clusters, and treating 1 symptom may potentially alleviate other symptoms in that cluster. The Living Well with Kidney Disease and Effective Symptom Management Consensus Conference convened health experts and leaders of kidney advocacy groups and kidney networks worldwide to discuss the effects of unpleasant symptoms related to CKD on the health and well-being of those affected, and to consider strategies for optimal symptom management. Optimizing symptom management is a cornerstone of conservative and preservative management which aim to prevent or delay dialysis initiation. In persons with kidney dysfunction requiring dialysis (KDRD), incremental transition to dialysis and home dialysis modalities offer personalized approaches. KDRD is proposed as the preferred term given the negative connotations of "failure" as a kidney descriptor, and the success stories in CKD journeys. Engaging persons with CKD to identify and prioritize their personal values and individual needs must be central to ensure their active participation in CKD management, including KDRD. Person-centered communication and care are required to ensure diversity, equity, and inclusion; education/awareness that considers the health literacy of persons with CKD; and shared decision-making among the person with CKD, care partners, and providers. By putting the needs of people with CKD, including effective symptom management, at the center of their treatment, CKD can be optimally treated in a way that aligns with their goals.

Interaction of Hydration Status and Physical Activity Level on Early Renal Damage in Children: A Longitudinal Study

Background

Optimal water intake positively affects various aspects of human physiology, especially renal function. Physical activity (PA) may have an impact on hydration status and renal health, but the interaction of hydration status and PA level on renal function is not well-studied in children.

Methods

We conducted four waves of urine assays in our child cohort (PROC) study from October 2018 to November 2019 in Beijing, China. We measured urinary specific gravity, β2-microglobulin (β2-MG), and microalbumin (MA) excretion to assess hydration status and renal damage in the context of PA level and other covariates among 1,914 primary school children. We determined the associations of renal damage with the interaction of hydration status and PA level using generalized linear mixed-effects models.

Results

The prevalence of dehydration was 35.0%, 62.1%, 63.9%, and 63.3%, and the prevalence of insufficient PA was 86.2%, 44.9%, 90.4%, and 90.2% from wave 1 to wave 4 among 1,914 primary school children. From wave 1 to wave 4, the prevalence of renal tubular damage had a significant increasing trend of 8.8%, 15.9%, 25.7%, and 29.0% (Z = 16.9, P &lt; 0.001), while the prevalence of glomerular damage revealed a declining trend of 5.6%, 5.5%, 4.4%, and 4.1% (Z = −2.4, P = 0.016). There were stable longitudinal associations of renal tubular and glomerular damage with hydration status (euhydration: OR = 0.50 and 0.33, respectively) but not with PA level. In multivariate analysis, significant interactions of hydration status and PA level were noted with renal tubular damage (β = 0.43, P = 0.014) and glomerular damage (β = 0.60, P = 0.047). Children with euhydration and insufficient PA were less likely to have renal tubular damage (OR = 0.46, 95% CI: 0.39, 0.53) or glomerular damage (OR = 0.28, 95% CI: 0.20, 0.39); children with euhydration and sufficient PA were also less likely to have renal tubular damage (OR = 0.57, 95% CI: 0.44, 0.75) or glomerular damage (OR = 0.47, 95% CI: 0.30, 0.74), adjusting for age, sex, BMI z-score, standardized SBP, sleep duration, computer/cell phone screen time, and fruit and vegetable intake.

Conclusion

Children with euhydration and either sufficient or insufficient PA were less likely to have early renal damage. Adequate daily water intake for children is important, especially after PA.

Renal Health Benefits of Rural City Planning in Japan

Progression of chronic kidney disease (CKD) is a substantial threat because it is associated with reduced healthy life expectancy and quality of life, and increase in economic burden. Research indicates people with nondialysis CKD often have lower physical functioning and that improvement of physical activity may contribute to maintaining renal health. Another issue with the current treatment of CKD is that the synergistic effects of rural depopulation due to aging and uncontrolled rural city sprawling will increase the number of under-served healthcare areas. To ensure the quality of renal health care, hospital integration is desirable, under the condition of reconstruction of the public transport system for physically and socially vulnerable people. Recently, medical and non-medical scientists advocate the challenge of city planning for population health. The links between city design and health such as cardiovascular disease, obesity, type 2 diabetes and mental disorders, have been widely studied, except for renal health. Based on our experience in a Kidney and Lifestyle-related Disease Center, we propose the idea that city planning be prioritized to improve renal health through two main streams: 1) Improve physical status by use of public and active transportation including daily walking and cycling; and 2) Equal accessibility to renal health services. Many countries, including Japan, have enacted plans and public policy initiatives that encourage increased levels of physical activity. We should focus on the impact of such movement on renal as well as general health.

Association of alcohol consumption with the incidence of proteinuria and chronic kidney disease: a retrospective cohort study in Japan

BACKGROUND

The difference in the clinical impact of alcohol consumption on kidney function based on sex remains to be elucidated. This study aimed to assess the association between the dose of alcohol consumption and the incidence of proteinuria and chronic kidney disease stratified by sex.

METHODS

This retrospective cohort study included 26,788 workers (19,702 men and 7086 women) with normal renal function (estimated glomerular filtration rate ≥ 60 mL/min/1.73 m²) at annual health examinations between January 2010 and March 2015 in Japan. The main exposure was alcohol consumption. The primary outcomes were the incidence of proteinuria (dipstick urinary protein ≥ 1) and incidence of low estimated glomerular filtration rate (eGFR; rate < 60 mL/min per 1.73 m²; decreased from the baseline eGFR by 25%).

RESULTS

During a median observational period of 4 years (interquartile range: 2-6), 1993 (10.1%) men and 462 (6.5%) women developed proteinuria, whereas 667 (3.4%) men and 255 (3.6%) women developed low eGFR. After adjustment for clinically relevant factors using a Cox proportional hazards model, alcohol consumption of ≥ 46 g/day in females was significantly associated with the incidence of proteinuria (hazard ratio, 1.57; 95% confidence interval, 1.10-2.26) and low eGFR (hazard ratio, 1.62; 95% confidence interval, 1.04-2.53). However, no significant association between alcohol consumption and primary outcomes was observed in men.

CONCLUSIONS

In conclusion, daily higher alcohol consumption was significantly associated with a higher incidence of proteinuria and low eGFR among women. Women might be prone to high alcohol consumption with kidney dysfunction.

Impact of Medication Adherence and Glycemic Control on the Risk of Micro- and Macrovascular Diseases in Patients with Diabetes

PURPOSE

Our purpose in the research was to clarify the impact of medication adherence to oral hypoglycemic agents during a 1-year period and subsequent glycemic control on the risk of micro- and macrovascular diseases.

METHODS

Examined was a nationwide claims database on 13,256 individuals with diabetic eye disease without requiring prior treatment, 7,862 without prior initiation of dialysis, 15,556 without prior coronary artery disease, 16,243 without prior cerebrovascular disease, and 19,386 without prior heart failure from 2008 to 2016 in Japan. Medication adherence was evaluated by the proportion of days covered. Patients were considered to have poor adherence if the proportion of days covered was <80%. Multivariate Cox regression model identified risks of micro- and macrovascular diseases.

RESULTS

In each group, mean age was 53 to 54 years, HbA1c was 7.1% to 7.2%, and median follow-up period was 4.6 to 5.1 years, and the percentage of poor adherence was approximately 30%. During the study period, 532 treatment-requiring diabetic eye disease, 75 dialysis, 389 coronary artery disease, 316 cerebrovascular disease, and 144 heart failure events occurred. Multivariate Cox regression model revealed that the hazard ratio (95% confidence interval) of dialysis in the poor adherence group was 2.04 (1.27-3.30) compared with the good adherence group. The hazard ratios in the poor adherence/poor glycemic control group were 3.34 (2.63-4.24) for treatment-requiring diabetic eye disease, 4.23 (2.17-8.26) for dialysis, 1.69 (1.23-2.31) for coronary artery disease, and 2.08 (1.25-3.48) for heart failure compared with the good adherence/good glycemic control group.

CONCLUSIONS

Poor medication adherence was an independent risk factor for the initiation of dialysis, suggesting that clinicians must pay close attention to these patients.

Ultraprocessed food consumption and kidney function decline in a population-based cohort in the Netherlands

BACKGROUND

Ultraprocessing makes food products more convenient, appealing, and profitable. Recent studies show that high ultraprocessed food (UPF) intake is associated with cardiometabolic diseases.

OBJECTIVES

The aim of this study is to investigate the association between UPF consumption and risks of kidney function decline in the general population.

METHODS

In a prospective, general population-based Lifelines cohort from Northern Netherlands, 78,346 participants free of chronic kidney disease (CKD) at baseline responded to a 110-item FFQ. We used a multivariable regression analysis to study the associations of the proportion (in grams/day) of UPFs in the total diet with a composite kidney outcome [incident CKD or a ≥30% estimated glomerular filtration rate (eGFR) decline relative to baseline] and annual change in eGFR.

RESULTS

On average, 37.7% of total food intake came from UPFs. After 3.6 ± 0.9 years of follow-up, 2470 participants (3.2%) reached the composite kidney outcome. Participants in the highest quartile of UPF consumption were associated with a higher risk of the composite kidney outcome (OR, 1.27; 95% CI, 1.09-1.47; P = 0.003) compared with those in the lowest quartile, regardless of their macro- or micronutrient intake or diet quality. Participants in the highest quartile had a more rapid eGFR decline (β, -0.17; 95% CI, -0.23 to -0.11; P < 0.001) compared with those in the lowest quartile. Associations were generally consistent across different subgroups.

CONCLUSIONS

Higher UPF consumption was associated with a higher risk of a composite kidney outcome (incident CKD or ≥30% eGFR decline) and a more rapid eGFR decline in the general population, independent of confounders and other dietary indices.

Relationship between modifiable lifestyle factors and chronic kidney disease: a bibliometric analysis of top-cited publications from 2011 to 2020

BACKGROUND

Chronic kidney disease (CKD) affects 8 to 16% of the world's population and is one of the top ten important drivers of increasing disease burden. Apart from genetic predisposition, lifestyle factors greatly contribute to the incidence and progression of CKD. The current bibliometric analysis aims to characterize the current focus and emerging trends of the research about the impact of modifiable lifestyle factors on CKD.

METHODS

We searched articles addressing the impact of modifiable lifestyle factors on the incidence and/or progression of CKD, published between 2011 and 2020, from the Science Citation Index Expanded (SCIE) database. An adjusted citation index, which considered both the original citation count and publication year, was derived for the selection of most-cited publications. Publishing trends, co-authorship network, keywords, and research hotspots were analyzed and visualized.

RESULTS

Among the top 100 most influential articles, 32 were narrative reviews, 16 systematic reviews and/or meta-analysis, 44 clinical research, and 8 basic research. The United States occupied a dominant position in the perspective of article numbers and international partnerships, followed by European countries. The modifiable factors that drew the most and constant attention over the decade were diet or nutrition management reported in 63 papers, followed by obesity or body mass index (n = 27), and physical activity or exercises (n = 8). Alcohol consumption, fish oil, chain fatty-acids, and water-soluble vitamins were emerging hotspots identified in the recent most cited publications.

CONCLUSIONS

Based on the bibliometric analysis of the most influential articles, our study provides a comprehensive description of publishing trends and research focus over a decade in the field of lifestyle factors' impact on CKD. Diet, obesity, and physical activity were factors receiving the most attention in this topic.

Relation of Alcohol Intake to Kidney Function and Mortality Observational, Population-Based, Cohort Study

Data are conflicting about the effects of alcohol intake on kidney function. This population-based study investigated associations of alcohol intake with kidney function and mortality. The study cohort included adult participants in Exam-1, Exam-2 (6-year follow-up), and Exam-3 (20-year follow-up) of the Gubbio study. Kidney function was evaluated as estimated glomerular filtration rate (eGFR, CKD-Epi equation, mL/min × 1.73 m2). Daily habitual alcohol intake was assessed by questionnaires. Wine intake accounted for >94% of total alcohol intake at all exams. Alcohol intake significantly tracked over time (R > 0.66, p < 0.001). Alcohol intake distribution was skewed at all exams (skewness > 2) and was divided into four strata for analyses (g/day = 0, 1−24, 25−48, and >48). Strata of alcohol intake differed substantially for lab markers of alcohol intake (p < 0.001). In multivariable regression, strata of alcohol intake related cross-sectionally to eGFR at all exams (Exam-1: B = 1.70, p < 0.001; Exam-2: B = 1.03, p < 0.001; Exam-3: B = 0.55, p = 0.010) and related longitudinally to less negative eGFR change from Exam-1 to Exam-2 (B = 0.133, p = 0.002) and from Exam-2 to Exam-3 (B = 0.065, p = 0.004). In multivariable Cox models, compared to no intake, intakes > 24 g/day were not associated with different mortality while an intake of 1−24 g/day was associated with lower mortality in the whole cohort (HR = 0.77, p = 0.003) and in the subgroup with eGFR < 60 mL/min × 1.73 m2 (HR = 0.69, p = 0.033). These data indicate a positive independent association of alcohol intake with kidney function not due to a mortality-related selection.

Effect Modification of Hyperuricemia, Cardiovascular Risk, and Age on Chronic Kidney Disease in China: A Cross-Sectional Study Based on the China Health and Nutrition Survey Cohort

Introduction

The question of whether the increased burden of chronic kidney disease (CKD) is caused by the interaction of hyperuricemia and cardiovascular disease (CVD) risk factors or is accelerated by aging remains unresolved. The purpose of this study is to better understand the effect modification of hyperuricemia, cardiovascular risk, and age on CKD among the Chinese population.

Methods

This cross-sectional study of 8243 participants was derived from the China Health and Nutrition Survey (CHNS) in 2009. Inclusion criteria included age ≥18 years, non-pregnancy, and no history of high-protein diet prior to blood test. Demographics, comorbidities, health-related behaviors, and serum biomarkers were collected. Interaction association of hyperuricemia, CVD risk and age with CKD were analyzed using Logistic regression.

Results

CKD was detected in 359 (27.2%, 95% CI 24.8∼29.7%) of 1321 participants with hyperuricemia and 680 (9.8%, 95% CI 9.1∼10.5%) of 6,922 participants without hyperuricemia, and these patterns remained significant after controlling for age, gender, and Framingham risk score (adjusted odds ratio [aOR] 3.82, 95% CI 3.20∼4.57). We found a negative multiplicative interaction between hyperuricemia and CVD risk on CKD. The aOR in low-CVD risk groups was 5.51 (95% CI 4.03∼7.52), followed by medium-CVD risk groups (aOR: 3.64, 95% CI 2.61∼5.09) and high-CVD risk groups (aOR: 2.89, 95% CI 2.12∼3.96). CVD risk was less associated with CKD in hyperuricemia group (aOR: 0.92, 95% CI 0.68∼1.22) than in non-hyperuricemia group (aOR: 1.43, 95% CI 1.21∼1.70). Furthermore, hyperuricemia and age had a significant additive effect on CKD, with a synergy index of 2.26 (95% CI 1.45∼3.52). Coexisting with older age and hyperuricemia, the likelihood of developing CKD was higher than the sum of the two alone.

Conclusion

The link between hyperuricemia and CKD begins at a young age and becomes stronger in the low CVD risk group. For young adults, early detection of hyperuricemia, routine CVD risk assessment, and timely intervention of modifiable factors are warranted.

Fiber intake and health in people with chronic kidney disease

Emerging evidence suggests that diet, particularly one that is rich in dietary fiber, may prevent the progression of chronic kidney disease (CKD) and its associated complications in people with established CKD. This narrative review summarizes the current evidence and discusses the opportunities for increasing fiber intake in people with CKD to improve health and reduce disease complications. A higher consumption of fiber exerts multiple health benefits, such as increasing stool output, promoting the growth of beneficial microbiota, improving the gut barrier and decreasing inflammation, as well decreasing uremic toxin production. Despite this, the majority of people with CKD consume less than the recommended dietary fiber intake, which may be due in part to the competing dietary potassium concern. Based on existing evidence, we see benefits from adopting a higher intake of fiber-rich food, and recommend cooperation with the dietitian to ensure an adequate diet plan. We also identify knowledge gaps for future research and suggest means to improve patient adherence to a high-fiber diet.

The association between hypertriglyceridemic-waist phenotype and chronic kidney disease: a cohort study and meta-analysis

Evidence on the association between hypertriglyceridemic-waist phenotype (HTGW) and chronic kidney disease (CKD) is limited and inconsistent. We aimed to explore such association among 7406 Chinese aged ≥ 45 years in a cohort setting, followed by a meta-analysis. Participants were categorized into four phenotypes: NTNW (normal triglycerides and normal waist circumference), NTGW (isolated enlarged waist circumference), HTNW (isolated high triglycerides), and HTGW (high triglycerides and enlarged waist circumference). We used multivariate logistic regression to determine the association between different phenotypes and risk of CKD in the cohort study. For meta-analysis, we searched relevant studies from Embase, Medline, PubMed, and Web of Science from dataset inception up to May 1, 2021. A random-effect model was used to estimate the pooled effect and I² statistic was applied to evaluate heterogeneity. In the cohort study, compared to the NTNW phenotype, HTGW (OR 1.82, 95% CI 1.32 to 2.51, p < 0.01) and NTGW (OR 1.48, 95% CI 1.13 to 1.94, p = 0.004) were significantly associated with CKD risk after 4 years follow-up, but not for the HTNW phenotype. The meta-analysis also showed a positive association between HTGW phenotype and CKD risk (pooled OR 1.53, 95% CI 1.31 to 1.79, I² = 62.4%). Assessment of triglyceridemic-waist phenotypes might help to identify individuals with high-risk of developing CKD.

Metabolic and hormonal responses to chronic blood-flow restricted resistance training in chronic kidney disease: a randomized trial

Maintenance of glycemic and lipemic homeostasis can limit the progression of diabetic kidney disease. Resistance training (RT) is effective in controlling glycemia and lipemia in kidney disease; however, the effect of RT with blood flow restriction (RT+BFR) on these metabolic factors has not been investigated. We aimed to verify if chronic (6 months) RT and RT+BFR performed by patients with stage-2 chronic kidney disease (CKD) improves their glycemic homeostasis and immunometabolic profiles. Patients with CKD under conservative treatment (n = 105 (33 females)) from both sexes were randomized into control (n = 35 (11 females); age 57.6 ± 5.2 years), RT (n = 35 (12 females); age 58.0 ± 6.2 years), and RT+BFR (n = 35 (10 females); 58.0 ± 6.4 years) groups. Chronic RT or RT+BFR (6 months) was performed 3 times per week on non-consecutive days with training loading adjusted every 2 months, RT 50%-60%-70% of 1RM, and RT+BFR 30%-40%+50% of 1RM and fixed repetition number. Renal function was estimated with the glomerular filtration rate and serum albumin level. Metabolic, hormonal, and inflammatory assessments were analyzed from blood samples. Six months of RT and RT+BFR were similarly effective in improving glucose homeostasis and hormone mediators of glucose uptake (e.g., irisin, adiponectin, and sirtuin-1), decreasing pro-inflammatory and fibrotic proteins, and attenuating the progression of estimated glomerular filtration rate. Thus, RT+BFR can be considered an additional exercise modality to be included in the treatment of patients with stage 2 chronic kidney disease. Trial registration number: U1111-1237-8231. URL: http://www.ensaiosclinicos.gov.br/rg/RBR-3gpg5w/, no. RBR-3gpg5w. Novelty: Glycemic regulation induced by resistance training prevents the progression of CKD. Chronic RT and RT+BFR promote similar changes in glycemic regulation. RT and RT+BFR can be considered as non-pharmacological tools for the treatment of CKD.

Association between exercise frequency with renal and cardiovascular outcomes in diabetic and non-diabetic individuals at high cardiovascular risk

BACKGROUND

Guidelines recommend physical activity to reduce cardiovascular (CV) events. The association between physical activity and progression of chronic kidney disease (CKD) with and without diabetes is unknown. We assessed the association of self-reported physical activity with renal and CV outcomes in high-risk patients aged ≥ 55 years over a median follow-up of 56 months in post-hoc analysis of a previously randomized trial program.

METHODS

Analyses were done with Cox regression analysis, mixed models for repeated measures, ANOVA and χ2-test. 31,312 patients, among them 19,664 with and 11,648 without diabetes were analyzed.

RESULTS

Physical activity was inversely associated with renal outcomes (doubling of creatinine, end-stage kidney disease (ESRD)) and CV outcomes (CV death, myocardial infarction, stroke, heart failure hospitalization). Moderate activity (at least 2 times/week to every day) was associated with lower risk of renal outcomes and lower incidence of new albuminuria (p < 0.0001 for both) compared to lower exercise levels. Similar results were observed for those with and without diabetes without interaction for renal outcomes (p = 0.097-0.27). Physical activity was associated with reduced eGFR decline with a moderate association between activity and diabetes status (p = 0.05).

CONCLUSIONS

Moderate physical activity was associated with improved kidney outcomes with a threshold at two sessions per week. The association of physical activity with renal outcomes did not meaningfully differ with or without diabetes but absolute benefit of activity was even greater in people with diabetes. Thus, risks were similar between those with diabetes undertaking high physical activity and those without diabetes but low physical activity.

CLINICAL TRIAL REGISTRATION

http://clinicaltrials.gov.uniqueidentifier :NCT00153101.

Associations of a healthy lifestyle score from childhood to adulthood with subclinical kidney damage in midlife: a population-based cohort study

Background

The relationships of healthy lifestyle scores (HLS) of various kinds in adulthood with the risk of chronic kidney disease (CKD) have been reported, but little is known about the association of childhood lifestyle with later life CKD. This study examined the relationship of HLS from childhood to adulthood with subclinical kidney damage (SKD) in midlife, a surrogate measure for CKD.

Methods

Data were collected in an Australian population-based cohort study with 33 years follow-up. 750 participants with lifestyle information collected in childhood (ages 10–15 years) and midlife (ages 40–50 years), and measures of kidney function in midlife were included. The HLS was generated from the sum scores of five lifestyle factors (body mass index, smoking, alcohol consumption, physical activity, and diet). Each factor was scored as poor (0 point), intermediate (1 point), or ideal (2 points). Log-binomial regression was used to investigate the relationship of HLS in childhood and from childhood to adulthood with SKD defined as either 1) estimated glomerular filtration rate (eGFR) 30–60 mL/min/1.73m² or 2) eGFR> 60 mL/min/1.73m² with urine albumin-creatinine ratio ≥ 2.5 mg/mmol (males) or 3.5 mg/mmol (females), adjusting for socio-demographic factors and the duration of follow-up.

Results

The average HLS was 6.6 in childhood and 6.5 in midlife, and the prevalence of SKD was 4.9% (n = 36). Neither HLS in childhood nor HLS from childhood to adulthood were significantly associated with the risk of SKD in midlife.

Conclusions

A HLS from childhood to adulthood did not predict SKD in this middle-aged, population-based Australian cohort.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02627-0.

Association between metabolic scores for visceral fat and chronic kidney disease: A cross-sectional study

INTRODUCTION

Central obesity is closely linked to the risk of chronic kidney disease (CKD). This study aimed to evaluate the association between the novel central obesity index- metabolic score for visceral fat (METS-VF) and the risk of CKD in a Chinese population, and to compare its ability to predict CKD with other central obesity indices including waist circumference (WC), waist-to-height ratio (WHtR), lipid accumulation product (LAP), visceral adiposity index (VAI), a body shape index (ABSI), body roundness index (BRI), and cardiometabolic index (CMI).

METHODS

This cross-sectional study included 8866 individuals from China. Demographic information, lifestyle data, and medical history data were collected, and physical examinations, anthropometric measurements and laboratory tests were performed for each participant. CKD was defined as an estimated GFR< 60 ml/min/1.73m². Multivariate logistic regression models were used to evaluate the association between the METS-VF and the prevalence of CKD. Receiver operating characteristic (ROC) analyses were performed to assess and compare the predictive abilities of the central obesity indices and determine the optimal cut-off points.

RESULTS

A graded increase in the prevalence of CKD was observed with increasing METS-VF tertiles. Moreover, the METS-VF was independently associated with the risk of CKD after adjustment for current smoking, current drinking, physical activity level, diabetes, hypertension, CVD history and BMI. Compared with participants with a METS-VF in the lowest tertile, the multivariate-adjusted ORs and 95% CIs for participants with a METS-VF in the highest tertile were 3.943 (2.435-6.385) in the overall population, 3.585 (1.585-8.109) for men and 4.627 (2.485-8.616) for women. Significant interactions were found between the METS-VF and the risk of CKD by age (P value for interaction = 0.023). In ROC analysis, the METS-VF had a higher AUC value than other indices for predicting CKD in men and had comparable or higher AUC than other indices for women. For predicting CKD, the optimal cut-off value of the METS-VF was 6.891 for men and 6.744 for women. The METS-VF yielded the greatest Youden index among all indices for both sexes.

CONCLUSION

A higher METS-VF was independently associated with a greater risk of CKD. The METS-VF can be a useful clinical indicator for identifying CKD, as it had superior predictive power for CKD when compared with other central obesity indices.

OUP accepted manuscript

Cancer is the second leading cause of death in people with chronic kidney disease (CKD) after cardiovascular disease. The incidence of CKD in patients with cancer is higher than in the non-cancer population. Across various populations, CKD is associated with an elevated risk of cancer incidence and cancer death compared with people without CKD, although the risks are cancer site-specific. Higher risk of cancer is detectable in mild CKD [estimated glomerular filtration rate (eGFR) 60-89 mL/min/1.73 m2], although this risk is more obvious if sensitive markers of kidney disease are used, such as cystatin C. Independent of eGFR, albuminuria is associated with increased risk of site-specific cancer incidence and death. Here, we explore the potential mechanisms for the increased risk of cancer observed in CKD, including patient factors (shared risks such as cardiometabolic disease, obesity, smoking, diet, lifestyle and environment), disease (genetic, inflammatory and infective) and treatment factors. In particular, we discuss the ways in which renal adverse events associated with conventional chemotherapies and newer systemic anti-cancer therapies (including targeted and immunotherapies) may contribute to worse cancer outcomes in people with CKD. Finally, we review the potential benefits of acknowledging increased risk of cancer in risk prediction tools used for the management of CKD.

Lifestyle interventions for preventing and ameliorating CKD in primary and secondary care

PURPOSE OF REVIEW

Despite the growth in chronic kidney disease (CKD) epidemics, evidence-based lifestyle recommendations for primary prevention of CKD are limited by reliance on observational studies and predominantly pilot clinical trials.

RECENT FINDINGS

Emerging data have shown lifestyle modification strategies for primary CKD prevention with the most evidence favoring a healthy dietary pattern (rich in fruit, vegetables, potassium and have a higher plant-based to animal protein ratio), and diet low in sodium, being physically active, avoiding tobacco smoking, moderating alcohol consumption and maintaining a healthy body weight. The way these behavioral interventions can be implemented in practice should consider their synergistic benefit as well as mechanisms to facilitate long-term behavior change. Sustaining long-term behavior change remains a challenge in practice, particularly due to a lack of healthcare resources and behavior relapse. Some suggestions to mitigate this include ensuring adequate time is spent in intervention codesign and planning, utilizing adaptive trial/intervention designs with regular intervention tailoring for intervention dose, intensity, duration, and modality.

SUMMARY

A number of modifiable lifestyle behaviors consistently associate with developing CKD in the community. The current evidence base, despite its inherent limitations, may inform both public health recommendations and clinical practice.

Lifestyle Medicine and Economics: A Proposal for Research Priorities Informed by a Case Series of Disease Reversal

Chronic disease places an enormous economic burden on both individuals and the healthcare system, and existing fee-for-service models of healthcare prioritize symptom management, medications, and procedures over treating the root causes of disease through changing health behaviors. Value-based care is gaining traction, and there is a need for value-based care models that achieve the quadruple aim of (1) improved population health, (2) enhanced patient experience, (3) reduced healthcare costs, and (4) improved work life and decreased burnout of healthcare providers. Lifestyle medicine (LM) has the potential to achieve these four aims, including promoting health and wellness and reducing healthcare costs; however, the economic outcomes of LM approaches need to be better quantified in research. This paper demonstrates proof of concept by detailing four cases that utilized an intensive, therapeutic lifestyle intervention change (ITLC) to dramatically reverse disease and reduce healthcare costs. In addition, priorities for lifestyle medicine economic research related to the components of quadruple aim are proposed, including conducting rigorously designed research studies to adequately measure the effects of ITLC interventions, modeling the potential economic cost savings enabled by health improvements following lifestyle interventions as compared to usual disease progression and management, and examining the effects of lifestyle medicine implementation upon different payment models.

Vegetable Preference and Prediction of Proteinuria: A Retrospective Cohort Study

INTRODUCTION

Little information is available about the association between vegetable preference and chronic kidney disease.

METHODS

This retrospective cohort study included 10,819 university workers in Japan who underwent their annual health checkups between January 2005 and March 2013. According to a question "Do you like vegetables"? with 3 possible answers of "I like vegetables," "I like vegetables somewhat," or "I dislike vegetables," 2,831, 2,249, and 104 male workers and 3,902, 1,648, and 85 female workers were classified into the "like," "somewhat," and "dislike" groups, respectively. An association between vegetable preference and incidence of proteinuria (dipstick urinary protein ≥1+) was assessed using Cox proportional-hazards models adjusted for clinically relevant factors.

RESULTS

During the median observational period of 5.0 years, the incidence of proteinuria was observed in 650 (12.7%) male and 789 (14.1%) female workers. Among male workers, the "dislike" group had a significantly higher risk of proteinuria (multivariable-adjusted hazard ratio of "like," "somewhat," and "dislike" groups: 1.00 [reference], 1.05 [0.90-1.23], and 1.59 [1.01-2.50], respectively). Among female workers, vegetable preference was associated with the incidence of proteinuria in a dose-dependent manner (1.00 [reference], 1.20 [1.04-1.40], 1.95 [1.26-3.02], respectively).

CONCLUSION

"Do you like vegetables"? was a clinically useful tool to identify subjects vulnerable to proteinuria.

Effect of body mass index on the association between alcohol consumption and the development of chronic kidney disease

The influence of body mass or metabolic capacity on the association between alcohol consumption and lower risks of developing chronic kidney disease (CKD) is not fully elucidated. We examined whether the body mass index (BMI) affects the association between drinking alcohol and CKD. We defined CKD as an estimated glomerular filtration rate decline < 60 mL/min/1.73 m² and/or positive proteinuria (≥ 1+). Participants were 11,175 Japanese individuals aged 40–74 years without baseline CKD who underwent annual health checkups. Daily alcohol consumption at baseline was estimated using a questionnaire, and the participants were categorized as “infrequent (occasionally, rarely or never),” “light (< 20 g/day),” “moderate (20–39 g/day),” and “heavy (≥ 40 g/day).” Over a median 5-year observation period, 936 participants developed CKD. Compared with infrequent drinkers, light drinkers were associated with low CKD risks; adjusted hazard ratios (95% confidence intervals) were 0.81 (0.69–0.95). Stratified by BMI (kg/m²), moderate drinkers in the low (< 18.5), normal (18.5–24.9), and high (≥ 25.0) BMI groups had adjusted hazard ratios (95% confidence intervals) of 3.44 (1.60–7.42), 0.75 (0.58–0.98), and 0.63 (0.39–1.04), respectively. Taken together, the association between alcohol consumption and CKD incidence was not the same in all the individuals, and individual tolerance must be considered.

Optimizing Diet to Slow CKD Progression

Due to the unique role of the kidney in the metabolism of nutrients, patients with chronic kidney disease (CKD) lose the ability to excrete solutes and maintain homeostasis. Nutrient intake modifications and monitoring of nutritional status in this population becomes critical, since it can affect important health outcomes, including progression to kidney failure, quality of life, morbidity, and mortality. Although there are multiple hemodynamic and metabolic factors involved in the progression and prognosis of CKD, nutritional interventions are a central component of the care of patients with non-dialysis CKD (ND-CKD) and of the prevention of overweight and possible protein energy-wasting. Here, we review the reno-protective effects of diet in adults with ND-CKD stages 3-5, including transplant patients.

Kidney Function, Kidney Function Decline, and the Risk of Dementia in Older Adults: A Registry-Based Study

OBJECTIVE

Community-based reports regarding the association between the estimated glomerular filtration rate (eGFR) and dementia risk show conflicting results. The aim of this study is to investigate the links among kidney function, kidney function decline, and dementia incidence.

METHODS

We analyzed the association of eGFR with the risk of dementia (defined as a new dementia diagnosis or initiation of dementia treatments) among 329,822 residents of Stockholm who accessed health care during 2006 to 2011, were ≥65 years of age, had no history of dementia, or underwent kidney replacement therapy. We also estimated the rate of eGFR decline among 205,622 residents with repeated eGFR measurements during the first year of observation and investigated its association with subsequent dementia risk.

RESULTS

We detected 18,983 cases of dementia (5.8% of participants) over a median follow-up of 5 years. Dementia incidence rates were progressively higher with lower eGFR: from 6.56/1,000 person-years in those with eGFR of 90 to 104 mL/min to 30.28/1,000 person-years in those with eGFR <30 mL/min. After multivariable adjustment, lower eGFR was associated with a higher dementia risk (hazard ratio [HR] 1.71, 95% confidence interval [CI] 1.54-1.91 in eGFR 30-59 mL/min; HR 2.62, 95% CI 1.91-3.58 in eGFR <30 mL/min) compared with eGFR of 90 to 104 mL/min. A steeper decline in eGFR (decline >2 mL/min/1.73 m2/y) within 1 year was associated with higher dementia risk. Risk magnitudes were stronger for vascular dementia than for Alzheimer dementia. As many as 10% (95% CI 6%-14%) of dementia cases could be attributed to eGFR <60 mL/min/1.73 m2, a proportion higher than that attributed to other dementia risk factors such as cardiovascular disease and diabetes.

CONCLUSIONS

Both lower kidney function and steeper kidney function decline are associated with the development of dementia.

Leisure-time, occupational, and commuting physical activity and the risk of chronic kidney disease in a working population

Physical activity has been linked to a lower risk of chronic kidney disease (CKD); however, evidence on the relationship between domain-specific physical activity and CKD is scarce. This study aimed to examine the risk of CKD in relation to leisure-time, occupational, and commuting physical activities in a large occupational cohort in Japan. Participants were 17,331 workers (20-65 years old) without CKD and were followed-up for a maximum period of 13 years. Incident CKD was defined as an estimated glomerular filtration rate of < 60 mL/min/1.73 m² and/or proteinuria determined using the dipstick test. The Cox proportional hazards models were used to examine the associations. During 147,752 person-years of follow-up, 4013 participants developed CKD. Workers who were standing or walking at work and those who were fairly active at work had adjusted hazard ratios of 0.88 (95% confidence interval 0.86-0.96) and 0.89 (95% confidence interval 0.78-1.02), respectively, for developing CKD than sedentary workers. Leisure-time physical activity and walking for commute were not associated with CKD risk. Our findings suggest that occupational, but not leisure-time and commuting physical activities, is associated with a lower CKD risk.

Nitric oxide signalling in kidney regulation and cardiometabolic health

The prevalence of cardiovascular and metabolic disease coupled with kidney dysfunction is increasing worldwide. This triad of disorders is associated with considerable morbidity and mortality as well as a substantial economic burden. Further understanding of the underlying pathophysiological mechanisms is important to develop novel preventive or therapeutic approaches. Among the proposed mechanisms, compromised nitric oxide (NO) bioactivity associated with oxidative stress is considered to be important. NO is a short-lived diatomic signalling molecule that exerts numerous effects on the kidneys, heart and vasculature as well as on peripheral metabolically active organs. The enzymatic L-arginine-dependent NO synthase (NOS) pathway is classically viewed as the main source of endogenous NO formation. However, the function of the NOS system is often compromised in various pathologies including kidney, cardiovascular and metabolic diseases. An alternative pathway, the nitrate-nitrite-NO pathway, enables endogenous or dietary-derived inorganic nitrate and nitrite to be recycled via serial reduction to form bioactive nitrogen species, including NO, independent of the NOS system. Signalling via these nitrogen species is linked with cGMP-dependent and independent mechanisms. Novel approaches to restoring NO homeostasis during NOS deficiency and oxidative stress have potential therapeutic applications in kidney, cardiovascular and metabolic disorders.