A higher ratio of refined grain to whole grain is associated with a greater likelihood of chronic kidney disease: a population-based study

Association between Whole Grain Intake and Chronic Kidney Disease

BACKGROUND

The relationship between whole grain intake and chronic kidney disease (CKD) remains uncertain.

OBJECTIVE

This study aimed to evaluate the association between whole grain intake and risk of CKD in Chinese adults.

METHODS

The present cross-sectional study used data from the China Health and Nutrition Survey conducted in 2009. Whole grain intake was measured using 3 consecutive 24-h dietary recalls and a household food inventory. A multivariable logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of CKD. In addition, a restricted cubic spline was used to investigate the dose‒response relationship between whole grain and risk of CKD.

RESULTS

A total of 6747 participants were included, 728 of whom had CKD. Compared with those in the lowest whole grain intake group, those in the higher grain intake group had an inverse association with risk of CKD (Q2: adjusted OR 0.70, 95% CI: 0.54, 0.89; Q3: adjusted OR 0.54, 95% CI: 0.42, 0.69; and Q4: adjusted OR 0.29, 95% CI: 0.21, 0.41). The association between whole grain intake and CKD seems to be stronger for individuals who were male (P for interaction = 0.008) or smokers (P for interaction = 0.013). In addition, the restricted cubic spline suggested an obvious L-shaped correlation.

CONCLUSIONS

Increased whole grain intake was associated with a decreased risk of CKD in Chinese adults.

Associations between dietary patterns and renal impairment in individuals with diabetes: a cross-sectional study

BACKGROUND

A variety of chronic diseases are affected by diet. To our knowledge, few studies have investigated the relationship between dietary patterns and renal impairment in individuals with diabetes within an Asian population. This study aimed to assess the relationship between renal impairment and dietary patterns in individuals with diabetes within a Chinese population.

METHODS

In this cross-sectional survey, we analysed data on 1522 participants with diabetes aged 18 years or older who took part in the China National Diabetic Chronic Complications Study. We utilised the Chinese Diabetes Complications Questionnaire, including the semiquantitative food frequency questionnaire (SQFFQ). We identified three dietary patterns using factor analysis: Chinese traditional, healthy and plant-based dietary patterns, and these dietary patterns were used to classify participants into four groups based on the quartiles of their scores. A decrease in the estimated glomerular filtration rate (eGFR; <60 mL/min/1.73 m2 ) and an increase in the albumin-to-creatinine ratio (ACR; ≥3 mg/mmol) were used as indicators of renal impairment. Binary logistic regression models were used to estimate the odds ratio (OR) of the highest quartile (Q4: high intake levels of each dietary pattern) for renal impairment compared to the lowest quartile (Q1: low intake levels of each dietary pattern).

RESULTS

Among the 1522 participants, there was a 5.5% prevalence of low eGFR, with prevalence rates of 5.2% in men and 5.9% in women, yet the prevalence of albuminuria was as high as 47.9%. After adjusting for confounders, participants in Q4 of the plant-based dietary pattern had a smaller OR for renal impairment than those in Q1.

CONCLUSIONS

Our findings demonstrated that a plant-based dietary pattern is associated with a reduced risk of renal impairment in a population with diabetes.

Association between dietary patterns and chronic kidney disease combined with hyperuricemia

Background and aims: Chronic kidney disease (CKD) combined with hyperuricemia is a concerning health issue, but the association between this condition and dietary patterns remains poorly understood. The aim of this study was to assess the associations between dietary patterns and CKD combined with hyperuricemia. Methods: This cross-sectional study was conducted involving 12 318 participants aged 18-79 years during 2018-2020. Dietary intake information was collected using a validated 110-item food frequency questionnaire. Factor analysis was used to identify major dietary patterns. CKD was defined as the presence of albuminuria or an estimated glomerular filtration rate <60 mL min-1 1.73 m-2. Hyperuricemia was defined as serum uric acid levels >420 μmol L-1 both in men and women. Logistic regression models were applied to assess the association between dietary patterns and the risk of CKD combined with hyperuricemia. Results: Five major dietary patterns were identified: 'healthy pattern', 'traditional pattern', 'animal foods pattern', 'sweet foods pattern', and 'tea-alcohol pattern', which together explained 38.93% of the variance in the diet. After adjusting for potential confounders, participants in the highest quartile of the traditional pattern had a lower risk of CKD combined with hyperuricemia (OR = 0.49, 95% CI: 0.32-0.74, Pfor trend < 0.01). Conversely, participants in the highest quartile of the sweet foods pattern had a higher risk compared to those in the lowest quartile (OR = 1.69, 95% CI: 1.18-2.42, Pfor trend < 0.01). However, no significant association was observed between the healthy pattern, animal foods pattern and tea-alcohol pattern and the risk of CKD combined with hyperuricemia. Conclusions: Our results suggest that the traditional pattern is associated with a reduced risk of CKD combined with hyperuricemia, whereas the sweet foods pattern is associated with an increased risk.

The association of dietary patterns with incident chronic kidney disease and kidney function decline among middle-aged Korean adults: a cohort study

OBJECTIVES

This study assessed the association of dietary patterns with the incidence of chronic kidney disease (CKD) and kidney function decline among Korean adults.

METHODS

Data were collected from the records of 20,147 men and 39,857 women who participated in the Health Examinees study. Principal component analysis was used to identify 3 dietary patterns (prudent, flour-based food and meat, and white rice-based), and CKD risk was defined using the Epidemiology Collaboration equation for estimated glomerular filtration rate: (eGFR) <60 mL/min/1.73 m2. A kidney function decline was defined as a >25% decrease in eGFR from baseline.

RESULTS

During the 4.2-year follow-up, 978 participants developed CKD and 971 had a 25% decline in kidney function. After adjusting for potential impact variables, compared with the lowest quartile of the prudent dietary pattern, participants in the highest quartile had a 37% lower risk of kidney function decline among men (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.47 to 0.85); while higher adherence to the flour-based food and meat dietary pattern was associated with an increased risk of CKD in both men (HR, 1.63; 95% CI, 1.22 to 2.19) and women (HR, 1.47; 95% CI, 1.05 to 2.05) as well as a decline in kidney function in both men (HR, 1.49; 95% CI, 1.07 to 2.07) and women (HR, 1.77; 95% CI, 1.33 to 2.35).

CONCLUSIONS

Although a higher adherence to the prudent dietary pattern was inversely associated with the risk of kidney function decline in men, there was no association with CKD risk. In addition, a higher adherence to the flour-based food and meat dietary pattern increased the risk of CKD and kidney function decline. Further clinical trials are needed to confirm these associations.

Higher Plasma Levels of Valerate Produced by Gut Microbiota May Have a Beneficial Impact on Renal Function

OBJECTIVE

Observational studies have evaluated the relationships among plasma short chain fatty acids (SCFA) produced by gut microbiota, renal function, and risk of chronic kidney disease (CKD). In the present study, Mendelian Randomization (MR) analysis was applied to obtain unconfounded estimates of the casual association of genetically determined plasma valerate (an SCFA) with kidney function and risk of CKD.

METHOD

MR was performed by using summary-level data from the largest genome-wide association studies (GWAS) conducted on plasma valerate, CKD, and estimated glomerular filtration rate (eGFR; separately in diabetic and nondiabetic individuals). Inverse variance weighted method (IVW), weighted median-based method, MR-Egger, as well as MR-Pleiotropy RESidual Sum and Outlier (PRESSO) were applied. Sensitivity analysis was conducted using the leave-one-out method.

RESULTS

No significant association was observed between plasma valerate and CKD (IVW: β = 0.234, p = 0.744). In contrast, plasma valerate was positively associated with eGFR in the total population (IVW: β = 0.049, p = 0.022) and among nondiabetic individuals (IVW: β = 0.058, p = 0.009), but not in the diabetic population (IVW: β = -0.052, p = 0.603). None of the estimated associations was subjected to significant level of heterogeneity. Furthermore, MR-PRESSO analysis did not show any chance of outlier for all estimates. The pleiotropy test, with very a negligible intercept and insignificant p value, also indicated no chance of pleiotropy for all of our estimations (all p > 0.539). The results of the MR-Robust Adjusted Profile Score were identical with the IVW estimates, highlighting again no possibility of pleiotropy. Results of the leave-one-out method demonstrated that the links were not driven by single-nucleotide polymorphisms.

CONCLUSIONS

Individuals with higher plasma valerate levels had better renal function, defined by eGFR. This finding was observed in the total population and in nondiabetic subjects, but not in those with diabetes. Further research is needed to elucidate the links among plasma valerate, kidney function, and CKD.

Higher HEI-2015 scores are associated with lower risk of gout and hyperuricemia: Results from the national health and nutrition examination survey 2007-2016

Gout, the most prevalent inflammatory arthritis, is becoming increasingly prevalent in the United States and across the world, and it adversely impacts people’s quality of life and their health. Few studies have focused on the relationship between daily dietary quality and gout, so the topic requires further exploration. Data were derived from the National Health and Nutrition Examination Survey 2007–2016, and the inclusion criteria of the analytic sample were (1) adults, age ≥20 years, with complete information about HEI-2015, gout, and uric acid; (2) complete information of demographics, lifestyle (BMI, smoking, drinking), and disease history [hypertension, chronic kidney disease (CKD), diabetes]. The quality of the daily diet was reflected using the Healthy Eating Index 2015 (HEI-2015). The baseline features of different groups were examined using the Scott-Rao chi-square tests, and the association between the HEI-2015 score and the risk of gout/hyperuricemia (HUA) was investigated using weighted logistic regression models. The effects of different dietary components in the HEI-2015 on reducing the risk of gout/HUA were evaluated by weighted quantile sum (WQS) regression models. After adjusting for demographic characteristics, behavioral covariates, and disease history, higher HEI-2015 scores were associated with a significantly lower risk of gout (OR: 0.878, 95% CI: 0.876–0.880) and HUA (OR: 0.978, 95% CI: 0.976–0.979) in weighted logistic regression. Dairy, whole grains, plant proteins, and added sugar contributed greatly in HEI-2015 to reducing gout risk (weights of WQS index: 42, 17.18, 16.13, and 7.93%, respectively). Dairy, total fruits, greens and beans, and plant proteins contributed greatly in HEI-2015 to reducing HUA risk (weights of WQS index: 28.9, 17.13, 16.84, and 11.39%, respectively). As the result, adherence to the American Dietary Guidelines may assist to decrease the risk of gout/HUA in American adults, and greater emphasis should be placed on dairy products, whole grains, fruits, legumes, and added sugars.

Clinical Efficacy of Persian Medicine Diet Combined with Western Medicine-Based Diet on Proteinuria in Pediatric Nephrotic Syndrome: A Randomized Controlled Clinical Trial

Introduction

Nephrotic syndrome (NS) is a common chronic kidney disorder during childhood. The most important characteristic of this disease is proteinuria. The Persian medicine (PM) has important dietary recommendations for strengthening the kidney function and treatment of this disease. The aim of this study was to investigate the effect of a diet including PM recommendations and general principles of Western medicine.

Materials and Methods

Twenty children with nephrotic syndrome were randomly divided into intervention and control groups and monitored for one month. The control group received a diet based on the general principles of Western medicine. In the intervention group, in addition to the Western medicine diet, dietary recommendations of PM were also prescribed including the pomegranate (Cydonia oblonga mill.), quince (Cydonia oblonga mill.), and whole grains (wheat and barley). A 24-hour dietary questionnaire was applied and anthropometric and biochemical indices including spot urine protein (proteinuria), albumin (Alb), urea, creatinine (Cr), total cholesterol (TC), and triglyceride (TG) were measured before and after the study.

Results

The amount of protein intake reduced significantly in the diet of both groups but the differences between the two groups were not significant. Proteinuria reduced significantly in both the Western and PM groups; however, proteinuria was significantly lower in the Persian medicine group compared to the control group. TC and Cr levels reduced significantly in the intervention group, although the changes were not significant compared to the control group.

Conclusion

The results of this study showed that adding dietary recommendations of the Persian medicine to the general rules of the Western medicine diet reduced proteinuria and improved the combat against nephrotic syndrome.

Associations of Whole Grain and Refined Grain Consumption With Metabolic Syndrome. A Meta-Analysis of Observational Studies

Background: The associations of whole grain and refined grain consumption with metabolic syndrome (MetS) has been evaluated in several epidemiological studies with conflicting results. This meta-analysis was therefore employed to further investigate the above associations. Method: We searched the PubMed, Web of Science and Embase database until March 2021 (without restriction for inclusion time), for observational studies on the associations of whole grain and refined grain consumption with MetS. The pooled relative risk (RR) of MetS for the highest vs. lowest category of whole grain and refined grain consumption, as well as their corresponding 95% confidence interval (CI) were calculated. Results: A total of 14 observational studies, which involved seven cross-sectional and seven prospective cohort studies, were identified. Specifically, nine studies were related to whole grain consumption, and the overall multi-variable adjusted RR demonstrated that the whole grain consumption was inversely associated with MetS (RR = 0.80, 95%CI: 0.67-0.97; P = 0.021). With regard to refined grain consumption, 13 studies were included. The overall multi-variable adjusted RR indicated that refined grain consumption was positively associated with MetS (RR = 1.37, 95%CI: 1.02-1.84; P = 0.036). Conclusions: The existing evidence suggests that whole grain consumption is negatively associated with MetS, whereas refined grain consumption is positively associated with MetS. Our result might be helpful to better consider the diet effect on MetS. However, more well-designed prospective cohort studies are needed to elaborate the concerned issues further.

The impact of type of dietary protein, animal versus vegetable, in modifying cardiometabolic risk factors: A position paper from the International Lipid Expert Panel (ILEP)

Proteins play a crucial role in metabolism, in maintaining fluid and acid-base balance and antibody synthesis. Dietary proteins are important nutrients and are classified into: 1) animal proteins (meat, fish, poultry, eggs and dairy), and, 2) plant proteins (legumes, nuts and soy). Dietary modification is one of the most important lifestyle changes that has been shown to significantly decrease the risk of cardiovascular (CV) disease (CVD) by attenuating related risk factors. The CVD burden is reduced by optimum diet through replacement of unprocessed meat with low saturated fat, animal proteins and plant proteins. In view of the available evidence, it has become acceptable to emphasize the role of optimum nutrition to maintain arterial and CV health. Such healthy diets are thought to increase satiety, facilitate weight loss, and improve CV risk. Different studies have compared the benefits of omnivorous and vegetarian diets. Animal protein related risk has been suggested to be greater with red or processed meat over and above poultry, fish and nuts, which carry a lower risk for CVD. In contrast, others have shown no association of red meat intake with CVD. The aim of this expert opinion recommendation was to elucidate the different impact of animal vs vegetable protein on modifying cardiometabolic risk factors. Many observational and interventional studies confirmed that increasing protein intake, especially plant-based proteins and certain animal-based proteins (poultry, fish, unprocessed red meat low in saturated fats and low-fat dairy products) have a positive effect in modifying cardiometabolic risk factors. Red meat intake correlates with increased CVD risk, mainly because of its non-protein ingredients (saturated fats). However, the way red meat is cooked and preserved matters. Thus, it is recommended to substitute red meat with poultry or fish in order to lower CVD risk. Specific amino acids have favourable results in modifying major risk factors for CVD, such as hypertension. Apart from meat, other animal-source proteins, like those found in dairy products (especially whey protein) are inversely correlated to hypertension, obesity and insulin resistance.

Adherence to healthy dietary pattern and risk of kidney disease: a systematic review and meta-analysis of observational studies

Epidemiological studies show that adherence to healthy dietary patterns may be associated with a lower risk of decline in kidney function. However, existing evidence has not been quantitatively gathered. Pertinent observational studies investigating the association of adherence to a healthy dietary pattern, either priori-defined dietary pattern/indices or data-driven dietary patterns, with risk of kidney disease in the general population were identified by searching Medline and Scopus databases to May 28, 2018. A random-effects meta-analysis was applied. The analysis included eight prospective cohorts (5734 cases among 569,688 participants) and five cross-sectional studies (1955 cases among 16,614 participants). Higher adherence to a healthy dietary pattern (either priori-defined or data-driven dietary patterns) was associated with a 28% lower risk of kidney disease in the analysis of prospective cohort studies (RR = 0.72, 95 % CI = 0.58, 0.86; I² = %71, n = 8). A subgroup analysis based on definition of healthy dietary pattern resulted in significant inverse association only in the subgroup of Dietary Approaches to Stop Hypertension dietary pattern (RR: 0.74, 95 % CI: 0.54, 0.93; I² = 73%, n = 5). A dose-response analysis indicated a monotonic inverse association between adherence to the Dietary Approaches to Stop Hypertension dietary pattern with risk of kidney disease. A 32% lower risk was observed in the analysis of cross-sectional studies (OR: 0.68, 95 %CI: 0.53, 0.83, I² = 0%, n = 5). The findings suggest that higher adherence to a healthy dietary pattern is associated with a lower risk of kidney disease.

Mediation of the effect of serum uric acid on the risk of developing hypertension: a population-based cohort study

Background

Serum uric acid (SUA) had been associated with incident hypertension, but it is uncertain whether and to what extent the effect of SUA is mediated by other metabolic factors.

Methods

Data from the China Health and Retirement Longitudinal Study (CHARLS) during 2011 to 2015 was employed for this study. A total of 7639 participants aged between 35 and 96 years without hypertension was included. Cox proportional hazards model was used to investigate the association between elevated SUA and hypertension. A mediation model was used to separately explore mediating effects (MEs) of metabolic factors on the association between SUA and incident hypertension.

Results

During a median 4.0 years of follow-up, 2348 individuals were diagnosed with hypertension. After adjustment for metabolic confounders, participants with the highest SUA quartile had a hazard ratio of 1.16 (1.02–1.33) compared with the lowest category for incident hypertension. The association between SUA and incident hypertension were partially mediated by waist circumference (WC; ME = 0.034), body mass index (BMI; ME = 0.016), triglycerides (TG; ME = 0.024), total cholesterol (TC; ME = 0.009), high density lipoprotein cholesterol (HDL-C; ME = 0.009), fasting plasma glucose (FPG; ME = 0.005), and glycated hemoglobin (HbA1c; ME = − 0.002). Additionally, proportional mediation was 32.7% by WC and 15.4% by BMI for obesity indicators; 23.1% by TG, 8.7% by TC, and 8.7% by HDL-C for blood lipid; and 4.8% by FPG and − 1.9% by HbA1c for blood glucose.

Conclusions

The positive association between elevated SUA concentration and hypertension was reconfirmed in a Chinese population. Obesity indicators, blood lipids, and blood glucose may play important mediating roles in the pathways.