Physical activity and albuminuria

Dose-Response Relationships of Moderate to Vigorous Physical Activity and Sedentary Time With Renal Function Indices in Adolescents With Reduced Renal Function: A Cross-Sectional Study

BACKGROUND

This study aimed to explore the associations between moderate to vigorous physical activity (MVPA) and sedentary time with renal function indices in adolescents with kidney disease.

METHODS

A cross-sectional study was conducted on 719 adolescents (median age 15 y, 40.6% female) with kidney disease from the National Health and Nutrition Examination Survey 2007-2016. The exposures were MVPA time and sedentary time. Renal metabolic parameters included serum uric acid (SUA), creatinine, blood urea nitrogen, the estimated glomerular filtration rate (eGFR), and the albumin creatinine ratio. Weighted multivariate regression analysis was used to estimate associations between exposures and outcomes.

RESULTS

After stratifying MVPA time, the regression effect values β (95% CI) for MVPA on SUA (Q2: -0.22 [-0.41 to -0.03]; Q3: -0.32 [-0.53 to -0.11]) and creatinine (Q2: -0.08 [-0.15 to -0.01]; Q3: -0.04 [-0.11 to 0.03]) gradually decreased with increasing MVPA time. In males (-0.76 [-1.19 to -0.32]), MVPA time was significantly associated with lower SUA levels compared with females (-0.14 [-0.38 to 0.10]). Notably, female adolescents who had an MVPA time exceeding 420 minutes exhibited lower albumin creatinine ratio (-75.37 [-146.63 to -4.11]). In addition, both recreational MVPA time (-0.26 [-0.45 to -0.06]) and sedentary time (-3.15 [-5.83 to -0.46]) were negatively associated with eGFR.

CONCLUSIONS

Our study found an association between MVPA and lower levels of SUA in male adolescents with kidney disease and albuminuria in female adolescents with kidney disease. In addition, MVPA was also negatively associated with creatinine and eGFR, whereas sedentary time was only associated with eGFR. Further studies are needed to confirm these findings.

High-Intensity Interval Training Ameliorates Tramadol-Induced Nephrotoxicity and Oxidative Stress in Experimental Rats

INTRODUCTION

Tramadol (TRA) is an opioid analgesic widely prescribed for moderate-to-severe pain; however, its abuse and chronic use have been associated with kidney damage. Considering the protective role of exercise training in reducing organ damage, this study aimed to assess the influence of high-intensity interval training (HIIT) on a male rat's kidney following chronic TRA administration.

METHODS

In this experimental study, 30 male Wistar rats were assigned to the following groups: control (CON; animals received normal saline five days a week in the first month and three days a week in the second month), exercise (EXE; animals conducted HIIT training according to exercise protocol five days a week for two months), TRA (animals received TRA 50 mg/kg (i.p.) as described for the CON group), EXE-TRA (animals received TRA and conducted exercise protocol), and EXE-SL (animals received normal saline and conducted exercise protocol). Then, serum IL-6 and IL-10 levels, tissue malondialdehyde (MDA), total antioxidant capacity (TAC), glutathione peroxidase (GPx), superoxide dismutase (SOD), and levels of albumin, urea, and creatinine (CR), along with pathological changes in the kidney, were measured. A p-value of <0.05 was considered significant using GraphPad Prism v.9 (GraphPad Software, La Jolla, California, USA).

RESULTS

The inflammatory cytokines IL-6 and IL-10 were significantly increased in the EXE and EXE-TRA groups compared to the TRA group. Chronic administration of TRA in the TRA group decreased antioxidant indicators TAC, GPx, and SOD in kidney tissue while increasing oxidative stress MDA compared to the CON group (p<0.05). In contrast, the EXE-TRA group showed higher levels of TAC, GPx, and SOD, while MDA decreased compared to the TRA group. Additionally, serum levels of urea and CR were increased in the TRA group compared to the CON group, whereas these levels were decreased in the EXE-TRA group compared to the TRA group. The inflammatory effect of HIIT training, due to severe hyperemia and mild inflammatory cell infiltration, was seen in all EXE groups. Pathological findings confirmed TRA-induced kidney damage through moderate hyaline cast presence and severe apoptosis in the TRA group. Other findings were in line with the above results.

CONCLUSION

These findings confirm the nephrotoxicity of chronic use of TRA through biochemical and oxidative markers and pathological outcomes. In addition, the result suggests that HIIT has the potential to mitigate the detrimental effects of TRA through reversing biochemical and oxidative markers, including TRA-induced apoptosis. Consequently, considering its restorative properties, HIIT could be explored as a prospective nephroprotective approach for long-term TRA treatment.

Association of kidney function with physical performance: the Maastricht study

BACKGROUND

Kidney failure has been associated with decreased physical capacity, although evidence regarding the physical performance of individuals with earlier stages of chronic kidney disease (CKD) remains limited.

METHODS

Cross-sectional data were derived from the prospective, population-based Maastricht Study. Multivariate linear regression models were fitted to assess the association of estimated glomerular filtration rate (eGFR) and albuminuria categories with physical performance test outcomes.

RESULTS

Overall, 7396 participants were included. Compared to eGFR 60-90 ml/min/1.73 m2, values < 60 ml/min/1.73 m2 were associated with significantly shorter 6-min walk distance (β: - 13.04 m, 95% confidence intervals-CI - 19.95; - 6.13), worse timed chair rise stand test time (β: 0.91 s, 95% CI 0.36; 1.47), lower maximal grip (β: - 0.83 kg, 95% CI - 1.50; - 0.15) and elbow flexion (β: - 3.64 Nm, 95% CI - 7.11; - 0.16) strength. Additionally, eGFR > 90 ml/min/1.73 m2 was linked to significantly shorter 6-min walk distance (β: - 6.13 m, 95% CI - 9.44; - 2.82). Urinary albumin excretion > 30 mg/24 h was associated with shorter 6-min walk distance (β: - 12.48 m, 95% CI - 18.28; - 6.68), worse timed chair rise stand test time (β: 0.51 s, 95% CI 0.11; 1.06), lower maximal grip (β: - 1.34 kg, 95% CI - 1.91; - 0.76) and elbow flexion strength (β: - 3.31 Nm, 95% CI - 5.80; - 0.82).

CONCLUSIONS

Reduced eGFR and higher albuminuria levels were associated with worse physical performance, especially shorter 6-min walk distance and lower muscle strength. The relationship between eGFR and physical function was non-linear, with also high eGFR values being associated with worse performance, especially in the six-minute walk test.

Association of domain-specific physical activity with albuminuria among prediabetes and diabetes: a large cross-sectional study

BACKGROUND

Albuminuria, the presence of excess of protein in urine, is a well-known risk factor for early kidney damage among diabetic/prediabetic patients. There is a complex interaction between physical activity (PA) and albuminuria. However, the relationship of specific-domain PA and albuminuria remained obscure.

METHODS

Albuminuria was defined as urinary albumin/creatinine ratio (ACR) > 30 mg/g. PA was self-reported by participants and classified into transportation-related PA (TPA), occupation-related PA (OPA), and leisure-time PA (LTPA). Weighted logistic regression was conducted to compute the odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic spline (RCS) was used to evaluate the dose-response of PA domains with the risk of albuminuria.

RESULTS

A total of 6739 diabetic/prediabetic patients (mean age: 56.52 ± 0.29 years) were enrolled in our study, including 3181 (47.20%) females and 3558 (52.80%) males. Of them, 1578 (23.42%) were identified with albuminuria, and 5161(76.58%) were without albuminuria. Diabetic/prediabetic patients who adhered the PA guidelines for total PA had a 22% decreased risk of albuminuria (OR = 0.78, 95%CI 0.64-0.95), and those met the PA guidelines for LTPA had a 28% decreased of albuminuria (OR = 0.72, 95%CI 0.57-0.92). However, OPA and TPA were both not associated with decreased risk of albuminuria. RCS showed linear relationship between the risk of albuminuria with LTPA.

CONCLUSIONS

Meeting the PA guideline for LTPA, but not OPA and TPA, was inversely related to the risk of albuminuria among diabetic/prediabetic patients. Additionally, achieving more than 300 min/week of LTPA conferred the positive effects in reducing albuminuria among diabetic/prediabetic patients.

The Relationship Between Sarcopenia And Proteinuria, What Do We Know?

Sarcopenia is one of the most common geriatric syndromes in the elderly. It is defined as a decrease in muscle mass and function, and it can lead to physical disability, falls, poor quality of life, impaired immune system, and death. It is known that, the frequency of sarcopenia increases in the kidney patient population compared to healthy individuals. Although it is known that kidney disease can lead to sarcopenia; our knowledge of whether sarcopenia causes kidney disease is limited. Prior studies have suggested that protein energy wasting may be a risk of de novo CKD. Proteinuria is an important manifestation of kidney disease and there is a relationship between sarcopenia and proteinuria in diabetes, geriatric population, kidney transplant, and nephrotic syndrome. Does proteinuria cause sarcopenia or vice versa? Are they both the results of common mechanisms? This issue is not clearly known. In this review, we examined the relationship between sarcopenia and proteinuria in the light of other studies.

Review on adherence of the literature to official recommendations on albuminuria harmonization and standardization

Albuminuria standardization is a key issue to produce reliable and equivalent results between laboratories. We investigated whether official recommendations on albuminuria harmonization are followed in the literature. The PubMed database was searched from June 1 to September 26, 2021. The search terms included urine albumin, urine albumin-to-creatinine ratio (uACR), and albuminuria. A total of 159 articles were considered eligible; 50.9 % reported the type of urine collection. Specifically, 58.1 % collected a random spot urine specimen, 21 % collected a first morning void, and 6.2 % collected a 24-h specimen. Overall, 15 % of articles reported data on sample shipping, storage, and centrifugation and 13.3 % mentioned the preanalytical phase without any data on albuminuria. The method for albuminuria was properly described in 31.4 % of articles; of these, 54.9 % used immunological methods, and 8.9 % contained errors or missing data. Most articles (76.7 %) expressed test results as albuminuria-to-creatininuria ratio. Different decision levels were utilized in 130 articles; of these, 36 % used a decision level of ≤30 mg/g creatininuria and 23.7 % used three decision levels (≤30, 30-300, and ≥300 mg/g). The failure to follow guidelines on albuminuria harmonization was mainly found in the preanalytical phase. The poor awareness of the importance of preanalytical steps on test result may be a possible explanation.

Association between physical activity and risk of renal function decline and mortality in community-dwelling older adults: a nationwide population-based cohort study

BACKGROUND

Physical activity (PA) is an important risk factor associated with health outcomes. However, the relationship between PA and kidney function decline in older adults remains unclear. We examined the influence of PA on kidney function decline and mortality in community-dwelling older adults.

METHODS

Adults aged ≥ 65 years with an estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73 m² who had available health checkup data from 2009 to 2010 were included. The cohort was followed annually through December 2015 for anthropometric, sociodemographic, and medical information including outcomes and biennially for laboratory information from the health checkup. We divided these patients into three groups according to self-reported PA (Inactive group: no leisure-time PA, Active group: vigorous activity for at least 80 min/week or a sum of moderate-intensity activity and walking for at least 300 min/week, Low-active group: level of PA between the definitions of the other two groups). Associations between the intensity of PA and death, cardiovascular death, and ≥ 50% eGFR decline were investigated.

RESULTS

Among 102,353 subjects, 32,984 (32.23%), 54,267 (53.02%), and 15,102 (14.75%) were classified into the inactive, low-active, and active groups, respectively. The active group was younger, contained a higher proportion of men, and had higher frequencies of hypertension, diabetes mellitus, drinking, and smoking than the other groups. The active group had significantly lower incidence rates of mortality, cardiovascular mortality, and kidney function decline than the other groups (all p < 0.001). The active group also showed lower all-cause (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.70-0.82) and cardiovascular mortality (HR, 0.64; 95% CI, 0.53-0.78) and protection against ≥ 50% eGFR decline (HR, 0.81; 95% CI, 0.68-0.97) compared with the inactive group in the fully adjusted Cox proportional hazards regression model.

CONCLUSIONS

High PA was an independent modifiable lifestyle factor for reducing mortality and protecting against declines in kidney function in older adults.

Role of Physical Activity in Lowering Risk of End-Stage Renal Disease

OBJECTIVE

To investigate the association between the amount and intensity of leisure-time physical activity (LTPA) and the risk of end-stage renal disease (ESRD).

METHODS

The study examined a cohort of 543,667 participants aged 20 years and older who participated in a health screening program from January 1, 1996, through December 31, 2017. We identified 2520 individuals undergoing dialysis or who had a kidney transplant by linking participants' encrypted personal identification with the registry for ESRD with a median follow-up of 13 years. We classified participants into 5 categories measured by metabolic equivalent of tasks. Within each category, we analyzed the effect of moderate- and vigorous-intensity LTPA in reducing risk of ESRD. We used a Cox proportional hazards model to calculate hazard ratios (HRs).

RESULTS

We observed a dose-response relationship between LTPA and the risk of ESRD. The fully active group had a 12% lower hazard of ESRD compared with the no reported LTPA group (HR, 0.88; 95% CI, 0.80 to 0.98) adjusting for covariates including baseline estimated glomerular filtration rate and proteinuria. Within the same category of LTPA, vigorous-intensity exercise carried a 35% lower HR for ESRD compared with moderate-intensity exercise (HR, 0.65; 95% CI, 0.52 to 0.81). The effect was observed stronger among men, younger participants, and participants with diabetes or hyperlipidemia.

CONCLUSION

Sustained LTPA (≥ 150 minutes per week), particularly with vigorous intensity, significantly lowered the ESRD risk, even among individuals with comorbidities such as diabetes or hyperlipidemia. This finding suggested that patients with no reported LTPA with cardiovascular risks should engage in more LTPA to lower their risk of ESRD.

The Effects of Exercise Habit on Albuminuria and Metabolic Indices in Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study

Background and Objectives: Diabetes mellitus (DM) can cause macrovascular and microvascular complications, potentially resulting in further life-threatening complications. In general, the global prevalence of type 2 DM is increasing. To date, the care of DM comprises three aspects: diet, medication and exercise; among them, exercise is the most economical. Albuminuria is associated with renal injury and the progress of chronic kidney disease (CKD). The effects of habitual exercise in patients with new onset of diabetic kidney disease (DKD) have not been generally recognized. Our aim was to conduct an observational study regarding the effects of regular exercise on proteinuria and associated metabolic indices in patients with newly diagnosed type 2 DM. To investigate the effects of an exercise habit on albuminuria and the metabolic indices including renal function, blood glucose, and plasma lipids among patients with newly diagnosed type 2 DM. Materials and Methods: A cross-sectional study was conducted on newly diagnosed DM patients in two teaching hospitals in Taiwan from 1 June to 31 December 2020. The DM patients participated in the Diabetes Shared Care Network. According to the DM care mode, the patients’ blood biochemical results were analysed. Based on exercise duration, the patients were divided into two groups, i.e., the exercise group (≥150 min per week) and the non-exercise group (<150 min per week). Clinical demographic features and laboratory examination including blood and urine biochemistries were determined. Results: A total of 229 patients including 99 males (43.2%) and 130 females (56.8%) participated in the study. The proportion of DM patients with normoalbuminuria was higher (p < 0.05) in the exercise group (69.8%) than in the non-exercise group (53.7%), and the proportion of DM patients with micro or macroalbuminuria was lower in the exercise group (30.2%) than in the non-exercise group (46.3%). Levels of glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), triglycerides (TG) and high-density lipoprotein (HDL) were significantly different in both groups. Compared with the non-exercise group, lower HbA1c (6.89 ± 0.69 vs. 7.16 ± 1.05%) (p < 0.05), lower FPG (121.9 ± 25.7 vs. 140.5 ± 42.4 mg/dL) (p < 0.05), lower TG (115.6 ± 53.6 vs. 150.2 ± 15.4 mg/dL) (p < 0.05), and higher HDL (50.3 ± 11.4 vs. 44.1 ± 9.26 mg/dL) (p < 0.05) levels were noted in the exercise group. Conclusions: Regular exercise remains imperative and may bear an impact on albuminuria, blood glucose, and plasma lipids among type 2 DM patients. Therefore, medical staff and healthcare providers should encourage patients to maintain an exercise duration ≥150 min per week for preventing and controlling DM progression.

Systemic Immune-Inflammation Index Is Associated With Increased Urinary Albumin Excretion: A Population-Based Study

Background

Systemic immune-inflammation index (SII) is a novel inflammatory marker, and inflammation has been reported to be related with renal damage. We aimed to investigate the possible relationship between SII and albuminuria.

Methods

The present cross-sectional study was conducted among adults with complete data about SII and urinary albumin-to-creatinine ratio (ACR) in 2005–2018 National Health and Nutrition Examination Survey (NHANES). SII was calculated as the platelet count × neutrophil count/lymphocyte count. Albuminuria was defined as ACR >30mg/g. Weighted multivariable regression analysis and subgroup analysis were conducted to explore the independent relationship between SII and albuminuria.

Results

A total of 36,463 individuals were included in our analysis; 9.56% participants were categorized as having albuminuria overall and increased with the higher SII tertiles (tertile 1, 7.83%; tertile 2, 8.49%; tertile 3, 12.13%; p for trend <0.0001). Multivariable logistic regression showed that a higher SII level was associated with increased likelihood of albuminuria independently (OR = 1.31; 95% CI, 1.17–1.48, p<0.0001) after full adjustment. Subgroup analysis and interaction test showed that there was no significant dependence of gender, age, body mass index, hypertension, diabetes, non‐alcoholic fatty liver disease, and estimated glomerular filtration rate (eGFR) on this positive association (all p for interaction >0.05).

Conclusions

SII was positively associated with increased urinary albumin excretion in US adults. Further large-scale prospective studies are still needed to analyze the role of SII in albuminuria.

Cardiovascular and Renal Disease in Chronic Critical Illness

With advances in critical care, patients who would have succumbed in previous eras now survive through hospital discharge. Many survivors suffer from chronic organ dysfunction and induced frailty, representing an emerging chronic critical illness (CCI) phenotype. Persistent and worsening cardiovascular and renal disease are primary drivers of the CCI phenotype and have pathophysiologic synergy, potentiating one another and generating a downward spiral of worsening disease and clinical outcomes manifest as cardio-renal syndromes. In addition to pharmacologic therapies (e.g., diuretics, beta adrenergic receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and blood pressure control), special consideration should be given to behavioral modifications that avoid the pitfalls of polypharmacy and suboptimal renal and hepatic dosing, to which CCI patients may be particularly vulnerable. Smoking cessation, dietary modifications (e.g., early high-protein nutrition and late low-sodium diets), and increased physical activity are advised. Select patients benefit from cardiac re-synchronization therapy or renal replacement therapy. Coordinated, patient-centered care bundles may improve compliance with standards of care and patient outcomes. Given the complex, heterogeneous nature of cardiovascular and renal disease in CCI and the dismal long-term outcomes, further research is needed to clarify pathophysiologic mechanisms of cardio-renal syndromes in CCI and develop targeted therapies.

Effects of antihypertensive medication and high-intensity interval training in hypertensive metabolic syndrome individuals

Pharmacological and non-pharmacological therapies are simultaneously prescribed when treating hypertensive individuals with elevated cardiovascular risk (ie, metabolic syndrome individuals). However, it is unknown if the interactions between antihypertensive medication (AHM) and lifestyle interventions (ie, exercise training) may result in a better ambulatory blood pressure (ABP) control. To test this hypothesis, 36 hypertensive individuals with metabolic syndrome (MetS) under long-term prescription with AHM targeting the renin-angiotensin-aldosterone system (RAAS) were recruited. Before and after 4 months of high-intensity interval training (HIIT), participants completed two trials in a double-blind, randomized order: (a) placebo trial consisting of AHM withdrawal for 3 days and (b) AHM trial where individuals held their habitual dose of AHM. In each trial, 24-h mean arterial pressure (MAP) was monitored and considered the primary study outcome. Secondary outcomes included plasma renin activity (PRA) and aldosterone concentration to confirm withdrawal effects on RAAS, along with the analysis of urine albumin-to-creatinine ratio (UACR) to assess kidney function. The results showed main effects from AHM and HIIT reducing 24-h MAP (-5.7 mmHg, p < 0.001 and -2.3 mmHg, p = 0.007, respectively). However, there was not interaction between AHM and HIIT on 24-h MAP (p = 0.240). There was a main effect of AHM increasing PRA (p < 0.001) but no effect on plasma aldosterone concentration (p = 0.368). HIIT did not significantly improve RAAS hormones or the UACR. In conclusion, AHM and HIIT have independent and additive effects in lowering ABP. These findings support the combination of habitual AHM with exercise training with the goal to reduce ABP in hypertensive MetS individuals.

Association of maximal stress ergometry performance with troponin T and abdominal aortic calcification score in advanced chronic kidney disease

Background

Cardiac biomarkers Troponin T (TnT) and N-terminal pro-B-type natriuretic peptide (proBNP) and abdominal aortic calcification score (AAC) are associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). The effects of cardiac biomarkers and AAC on maximal exercise capacity in CKD are unknown and were studied.

Methods

One hundred seventy-four CKD 4–5 patients not on maintenance dialysis underwent maximal bicycle ergometry stress testing, lateral lumbar radiograph to study AAC, echocardiography and biochemical assessments.

Results

The subjects with proportional maximal ergometry workload (WMAX%) less than 50% of the expected values had higher TnT, proBNP, AAC, left ventricular end-diastolic diameter, left ventricular mass index, E/e’ and pulse pressure, and lower global longitudinal strain compared to the better performing patients. TnT (β = − 0.09, p = 0.02), AAC (β = − 1.67, p < 0.0001) and diabetes (β = − 11.7, p < 0.0001) remained significantly associated with WMAX% in the multivariable model. Maximal ergometry workload (in Watts) was similarly associated with TnT and AAC in addition to age, male gender, hemoglobin and diastolic blood pressure in a respective multivariate model.

AAC and TnT showed fair predictive power for WMAX% less than 50% of the expected value with AUCs of 0.70 and 0.75, respectively.

Conclusions

TnT and AAC are independently associated with maximal ergometry stress test workload in patients with advanced CKD.

Trial registration

http://www.ClinicalTrials.gov NCT04223726.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02251-y.

Impact of High Temperature on Post-Exercise Albuminuria in Dogs

Simple Summary

The literature suggests that strenuous exercise and exposure to high temperatures may cause physiologic proteinuria, but there are no available data showing the effect of high temperature on the occurrence of post-exercise albuminuria in dogs. The goal of the present study was to assess impact of high temperature on the occurrence of albuminuria. A period of about 30–40 min of intensive exercise at high temperatures did not lead to increased albuminuria. This suggests that there is no need to limit physical activity before urine tests in dogs, even at high temperatures, before a urinalysis.

Abstract

The literature suggests that strenuous exercise and exposure to high temperatures may cause physiologic proteinuria, but to our knowledge there have been no studies that have assessed the effect of high temperatures on the occurrence of post-exercise albuminuria in dogs. The goal of the study was to assess the impact of high temperatures on the occurrence of albuminuria. Thirteen healthy adult dogs—eight female (62%) and five male (38%) had to run 5 km at a temperature of 25 °C in grasslands which took about 30–40 min. Dogs underwent clinical examinations: echocardiography, abdominal ultrasound, blood hematology and biochemistry and urinalysis, including the ratio of albumin to creatinine (UAC). Baseline UAC was on the borderline of statistical significance for female dogs, but not for male dogs, before and after exercise. UAC was 0.31 ± 0.56 mg/mmol for female dogs and 0.36 ± 0.60 mg/mmol in male dogs before exercise. Immediately after exercise, UAC was 0.51 ± 0.58 mg/mmol in female dogs and 0.31 ± 0.40 mg/mmol in male dogs. Thus, a period of about 30–40 min of intensive exercise at high temperatures (25 °C) did not lead to increased albuminuria. This suggests that there is no need to limit the movement activity before urine tests in dogs, even at high temperatures, before urinalysis.

Occupational sedentary behavior and prediction of proteinuria in young to middle-aged adults: a retrospective cohort study

BACKGROUND

Although sedentary behavior is a risk factor of cardiometabolic diseases and mortality, little information is available about a clinical impact of occupational sedentary behavior on chronic kidney disease (CKD).

METHODS

The present retrospective cohort study included 10,212 workers of a national university in Japan who underwent annual health checkups between April 2006 and March 2013. Main exposure of interest was self-reported occupational sedentary behavior at the baseline visit. The outcome was the incidence of proteinuria defined as dipstick urinary protein of 1 + or more. The association between sedentary workers and the incidence of proteinuria was assessed using Cox proportional hazards models adjusting for clinically relevant factors, including television viewing time, the major home sedentary behavior.

RESULTS

During median 4.8 years (interquartile range 2.1-7.9) of the observational period, the incidence of proteinuria was observed in 597 (12.0%) males and 697 (13.3%) females. In males, sedentary workers were identified as a significant predictor of proteinuria (multivariable-adjusted hazard ratio of non-sedentary and sedentary workers: 1.00 [reference] and 1.35 [1.11-1.63]), along with longer television viewing time (< 30 min, 30-60 min, 1-2 h, 2-3 h, and > 3 h/day: 1.15 [0.93-1.42], 1.00 [reference], 1.24 [1.00-1.53], 1.41 [1.03-1.93], and 1.77 [1.13-2.76]), whereas not daily exercise time. In females, neither sedentary workers nor television viewing time was associated with the incidence of proteinuria.

CONCLUSIONS

In conclusion, male sedentary workers were at high risk of proteinuria. Occupational sedentary behavior may be a potentially modifiable target for the prevention of CKD.

Effects of exercise training on proteinuria in adult patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Rehabilitation effects of exercise training on adults with chronic kidney disease (CKD) have been generally recognised; however, the effects of exercise training on proteinuria have been underexplored. Our aim was to explore the effects of exercise training on proteinuria in adult CKD patients without renal replacement therapy.

METHODS

Randomised controlled trials (RCTs) and quasi-experimental studies examining the effects of exercise training on proteinuria in adults CKD patients without renal replacement therapy were searched in 10 electronic databases (MEDLINE, Embase, CINAHL, Cochrane Central Register of Controlled Trials, Allied and Complementary Medicine Database, SPORTDiscus with full text, Web of Science, China Wan Fang Database, China National Knowledge Internet, China Science and Technology Journal Database) until June 2019. The quality of quasi-experimental studies was assessed using the Joanna Briggs Institute Checklist for non-randomised experimental studies. The Cochrane risk of bias tool was used to evaluate the RCT quality.

RESULTS

We analysed 11 studies (623 participants). The 24-h urinary protein (24 h UP) level significantly decreased after exercise training in the within-group analysis (standard mean difference [SMD], 0.48; 95% confidence interval [CI], 0.08 to 0.88). There was a slight decrease in 24 h UP levels in the between-group analysis (SMD, 0.91; 95% CI, 0.00 to 1.82); however, the subgroup analysis showed that the change was insignificant (RCT: SMD, 0.24; 95% CI, - 0.44 to 0.92; quasi-experimental studies: SMD, 2.50; 95% CI, - 1.22 to 6.23). Exercise resulted in no significant differences in the urinary albumin-to-creatinine ratio in the between-group analysis (SMD, 0.06; 95% CI, - 0.54 to 0.67), but a significant decrease was found in the within-group analysis (SMD, 0.21; 95% CI, 0.04 to 0.38). No evidence of a decreased urinary protein-to-creatinine ratio was found after exercise (between-group analysis: SMD, 0.08 and 95% CI, - 0.33 to 0.48; within-group analysis: SMD, 0.04; 95% CI, - 0.25 to 0.32).

CONCLUSION

Exercise training does not aggravate proteinuria in adult CKD patients without renal replacement therapy. Further research is warranted in the future to determine the effectiveness of exercise training on proteinuria and to explore the mechanisms by which exercise training influences proteinuria.

Effects of low skeletal muscle mass and sarcopenic obesity on albuminuria: a 7-year longitudinal study

We aimed to identify the association between low skeletal muscle, sarcopenic obesity, and the incidence of albuminuria in the general population using a longitudinal study. Data from 29,942 subjects who underwent two or more routine health examinations from 2006 to 2013 were retrospectively reviewed. Relative skeletal muscle mass was presented using the skeletal muscle mass index (SMI), a measure of body weight-adjusted appendicular skeletal muscle mass estimated by bioelectrical impedance analysis. The cumulative incidence of albuminuria was 981 (3.3%) during the 7-year follow-up period. The hazard ratio of incident albuminuria was 1.44 (95% CI: 1.22–1.71, p for trend <0.001) in the lowest SMI tertile relative to the highest SMI tertile after multivariable adjustment. After additionally adjusting for general and central obesity, the hazard ratio was 1.35 (95% CI: 1.13–1.61, p for trend = 0.001) and 1.30 (95% CI: 1.08–1.56, p for trend = 0.003), respectively. Furthermore, the risk of developing albuminuria was much higher in the sarcopenic obesity group (HR: 1.49, 95% CI: 1.21–1.81, p for trend <0.001) compared to the other groups. Sarcopenic obesity, as well as low skeletal muscle, may lead to albuminuria in general populations.

Hypertension is associated with increased post-exercise albuminuria, which may be attenuated by an active lifestyle

Albuminuria is a known marker for endothelial dysfunction and cardiovascular events, even below the threshold of moderately increased albuminuria (MIA). Post-exercise increased albuminuria may precede the appearance of rest MIA, enabling detection of early injury. Modifying lifestyle for a population at risk for MIA is therefore of interest. Our aim was to evaluate post-exercise albuminuria in hypertensive compared with normotensive individuals and to analyze the effect of an active lifestyle on rest and post-exercise albumin excretion. The study cohort consisted of 3931 adults who participated in a health-screening program. Albuminuria was measured as urine albumin-to-creatinine ratio (ACR). Lifestyle was divided into three groups: non-active, less-active, and active according to regular sport activity, categorized as follows: none, <2.5 and ≥2.5 hours per week. Mean age was 47.7 years, and 31.2% (n = 1228) were diagnosed with hypertension. Both rest and post-exercise ACR were higher in hypertensive compared to normotensive participants. Rest ACR was higher in non-active compared to less-active and active hypertensive participants. Hypertensive participants with an active lifestyle had significantly lower post-exercise and delta ACR compared to less-active and non-active hypertensive participants. Parameters related to delta ACR in hypertensive participants were increased age, BMI, and diabetes, while active lifestyle and fitness (measured as METS achieved by a stress test) were protective. In conclusion, there is an association between hypertension and increased albumin excretion post-exercise, which can be attenuated with an active lifestyle.

Vitamin D deficiency increases risk of nephropathy and cardiovascular diseases in Type 2 diabetes mellitus patients

Background:

Vitamin D (VD) deficiency is associated with insulin function and secretion. It is linked with diabetes mellitus (DM) progression, and complications were also recorded. Therefore, the current study aimed to investigate serum VD level in Type 2 DM (T2DM) patients and its association with diabetic nephropathy and cardiovascular diseases (CVD).

Materials and Methods:

In this cross-sectional study, 205 patients with Type 2 diabetes age ranged from 39 to 75 years old were enrolled. Serum VD, high-sensitivity C-reactive protein (hs-CRP), and hemoglobin A1c (HbA1c) were measured. In addition, urinary albumin:creatinine ratio (ACR) was estimated.

Results:

Patients with Type 2 diabetes had a 78.5% VD level <30 ng/m. ACR and hs-CRP levels were significantly increased in patients with diabetes with VD <30 ng/m (P = 0.011 and P = 0.008, respectively). Female had significantly lower VD level than male P < 0.001. Patients exposed to sunlight had significantly higher VD level and lower hs-CRP levels compared with less-exposed, P value (0.001 and <0.001), respectively. Exercise significantly increased VD and decreased ACR levels in DM patients, P value (0.046 and 0.002), respectively. VD was positively associated with age (r = 0.355 P = 0.040) and negatively correlate with BMI (r = −0.502 P = 0.009), duration of disease (r = −0.498 P = 0.003), ACR (r = −0.384 P = 0.015), and HbA1c (r = −0.327 P = 0.032).

Conclusion:

The evidence from this study suggest that patients with Type 2 diabetes with VD deficiency are at higher risk for developing CVD and nephropathy.

Amount and pattern of physical activity and sedentary behavior are associated with kidney function and kidney damage: The Maastricht Study

Background

Chronic kidney disease, which is defined as having a reduced kidney function (estimated glomerular filtration rate (eGFR)) and/or signs of kidney damage (albuminuria), is highly prevalent in Western society and is associated with adverse health outcomes, such as cardiovascular disease. This warrants a search for risk factors of lower eGFR and higher albuminuria. Physical activity and sedentary behavior may be such risk factors.

Objective

To examine associations of physical activity (total, high, low), sedentary time and sedentary behavior patterns (breaks, prolonged bouts, average bout duration) with eGFR and albuminuria.

Methods

We examined these associations in 2,258 participants of the Maastricht Study (average age 60.1±8.1 years; 51.3% men), who wore an accelerometer 24h/day on 7 consecutive days. Associations with continuous eGFR and categories of urinary albumin excretion (UAE; <15 [reference category], 15-<30, ≥30 mg/24h) were evaluated with linear regression analyses and multinomial logistic regression analyses, respectively.

Results

After adjustment for potential confounders, each extra hour of total physical activity was associated with a more favorable kidney function (beta_eGFR = 2.30 (95%CI = 1.46; 3.14)), whereas each extra hour of sedentary behavior was associated with a more adverse kidney function (beta_eGFR = -0.71 (-1.08; -0.35)). Also, compared to individuals with the lowest levels of total physical activity, individuals with the highest levels had less kidney damage (OR_15-<30mg/24h = 0.63 (0.41; 0.96), OR_≥30mg/24h = 0.84 (0.53; 1.35). An extra hour of sedentary behavior was associated with more kidney damage (OR_{15-<30 mg/24h} = 1.11 (1.01; 1.22), OR_{≥30 mg/24h} = 1.10 (0.99; 1.22)). Further, a highly sedentary pattern was associated with a more adverse kidney function, but no association was seen with kidney damage.

Conclusions

Physical activity and sedentary behavior were associated with kidney function and kidney damage. Additionally, sedentary behavior patterns were associated with kidney function. Causal studies are required to examine whether this indeed implicates that prevention strategies should focus not only on increasing physical activity, but on reducing sedentary behavior as well.

Assessing Microvascular Function in Humans from a Chronic Disease Perspective

Microvascular dysfunction (MVD) is considered a crucial pathway in the development and progression of cardiometabolic and renal disease and is associated with increased cardiovascular mortality. MVD often coexists with or even precedes macrovascular disease, possibly due to shared mechanisms of vascular damage, such as inflammatory processes and oxidative stress. One of the first events in MVD is endothelial dysfunction. With the use of different physiologic or pharmacologic stimuli, endothelium-dependent (micro)vascular reactivity can be studied. This reactivity depends on the balance between various mediators, including nitric oxide, endothelin, and prostanoids, among others. The measurement of microvascular (endothelial) function is important to understand the pathophysiologic mechanisms that contribute to MVD and the role of MVD in the development and progression of cardiometabolic/renal disease. Here, we review a selection of direct, noninvasive techniques for measuring human microcirculation, with a focus on methods, interpretation, and limitations from the perspective of chronic cardiometabolic and renal disease.

Diabetes with early kidney involvement may shorten life expectancy by 16 years

This study aimed to identify the excess risks associated with diabetic patients with early kidney involvement (early diabetic kidney disease). The mortality risks of early diabetic kidney disease, defined as diabetes in early stages 1-3 chronic kidney disease (CKD), were assessed from a cohort of 512,700 adults in Taiwan participating in a health surveillance program from 1994-2008. Three related groups were identified and compared: diabetes without CKD, early diabetic kidney disease, and early CKD without diabetes. Deaths were ascertained through the National Death Registry. One-third of diabetics had early kidney disease, and approximately two-thirds of patients were classified with early CKD due to proteinuria. Patients with early diabetic kidney disease had more lifestyle risks such as inactivity or obesity, which characteristically amplified excess mortality by up to five times. The three-fold increase in all-cause mortality (hazard ratio 3.16) and a 16-year loss in life expectancy made early diabetic kidney disease a serious and yet often overlooked disease, with most patients unaware of their kidney involvement. Mortality for early diabetic kidney disease was nearly twice as high as that for early CKD (hazard ratio 2.01) or diabetes without CKD (hazard ratio 1.79). The 16-year life span loss is much worse than individually from early CKD (six years) or diabetes (ten years). Thus, identifying early proteinuria among diabetic patients and realizing the importance of reducing lifestyle risks like inactivity is a clinical challenge, but can save lives.

Associations between proteinuria and cardiovascular risk factors among hypertensive patients in Andkhoy, Afghanistan

Proteinuria in hypertension is an early marker of renal disease and a predictor for the progression of end stage renal disease, and cardiovascular diseases. This study was designed to determine the prevalence of proteinuria and its association with cardiovascular risk factors among adult hypertensive patients in Afghanistan. Five hundred fifty-five patients with a high blood pressure recorded in an outpatient clinic in Andkhoy, Afghanistan from December 2014 to May 2015, were included in this study. Data obtained from each patient, included demographic characteristics, body mass index, blood pressure patterns, cardiovascular history, cardiovascular risk factors, comorbidity, and current drug-therapy. Dipstick screening for proteinuria was performed with reagent test strips. The mean age of the patients was 57.9 ± 13.3 years, and a female predominance was observed (n = 333, 60%). The prevalence of proteinuria was 67.2%. The predictors of proteinuria were found to be age ≥65 years (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.00-1.04), smoking (OR 1.88, 95% CI 1.17-3.02), heart failure (OR 2.23, 95% CI 1.13-4.41), and diabetes mellitus (OR 3.41, 95% CI 1.49-7.81). In conclusion, this study shows that proteinuria is highly prevalent among hypertensive outpatients in an outpatient clinic in Andkhoy, Afghanistan, especially in those with high cardiovascular risk.

Sarcopenia is associated with albuminuria independently of hypertension and diabetes: KNHANES 2008-2011

INTRODUCTION

Although sarcopenia is associated with metabolic disorders, its influence on albuminuria has not been determined. The aim of this study was to identify the relationship between sarcopenia and albuminuria in the general population.

METHODS

This was a population-based, cross-sectional study using a nationally representative sample of 2326 subjects aged ≥20years from the Korea National Health and Nutrition Examination Surveys of 2008-2011. Appendicular skeletal muscle (ASM) measured by dual-energy X-ray absorptiometry was used to assess sarcopenia, which was defined as ASM divided by body mass index, as recommended by the international consensus meeting of the National Institutes of Health. Albuminuria was defined as an albumin-to-creatinine ratio of ≥30mg/g using random spot urine samples.

RESULTS

A total of 385 (16.5%) subjects were classified as having albuminuria. Sarcopenic subjects showed a higher proportion of albuminuria than subjects without sarcopenia (odds ratios [ORs]=2.17-3.26, all P<0.05) after stratification based on the presence of hypertension, diabetes, or metabolic syndrome and a higher homeostasis model assessment of insulin resistance (all P<0.001). The albuminuria risk was comparable between insulin-sensitive subjects with sarcopenia and insulin-resistant subjects with preserved muscle mass. A multiple logistic regression analysis also demonstrated that sarcopenia was independently associated with albuminuria (OR=1.61, 95% confidence interval [CI]=1.04-2.48, P<0.05). The association between sarcopenia and albuminuria remained strong in the elderly population (ORs=1.80-2.68, P<0.05), whereas it lost its significance in the younger age group. Furthermore, the risk of albuminuria was much higher in sarcopenic obese subjects than in other groups (OR=4.90, 95% CI=3.23-7.43, P<0.001).

CONCLUSIONS

Sarcopenia was associated with an increased risk of albuminuria independent of hypertension, diabetes, and metabolic syndrome. Sarcopenia and obesity had a synergistic impact on the increased risk of albuminuria. This suggests that sarcopenic obesity as well as sarcopenia alone may be considered as novel risk factors for albuminuria.

Objectively measured sedentary time, physical activity and kidney function in people with recently diagnosed Type 2 diabetes: a prospective cohort analysis

AIM

To assess the prospective association between objectively measured physical activity and kidney function over 4 years in people with Type 2 diabetes.

METHODS

Individuals (120 women and 206 men) participating in the ADDITION-Plus trial underwent assessment of sedentary time (SED-time), time spent in moderate-to-vigorous-intensity physical activity (MVPA) and total physical activity energy expenditure (PAEE) using a combined heart rate and movement sensor, and kidney function [estimated glomerular filtration rate (eGFR), serum creatinine and urine albumin-to-creatinine ratio (ACR)] at baseline and after 4 years of follow-up. Multivariate regression was used to quantify the association between change in SED-time, MVPA and PAEE and kidney measures at four-year follow-up, adjusting for change in current smoking status, waist circumference, HbA1c , systolic blood pressure, triglycerides and medication usage.

RESULTS

Over 4 years, there was a decline in eGFR values from 87.3 to 81.7 ml/min/1.73m(2) (P < 0.001); the prevalence of reduced eGFR (eGFR < 60 ml/min/1.73m(2) ) increased from 6.1 to 13.2% (P < 0.001). There were small increases in serum creatinine (median: 81-84 μmol/l, P < 0.001) and urine ACR (median: 0.9-1.0 mg/mmol, P = 0.005). Increases in SED-time were associated with increases in serum creatinine after adjustment for MVPA and cardiovascular risk factors (β = 0.013, 95% CI: 0.001, 0.03). Conversely, increases in PAEE were associated with reductions in serum creatinine (β = -0.001, 95% CI: -0.003, -0.0001).

CONCLUSION

Reducing time spent sedentary and increasing overall physical activity may offer intervention opportunities to improve kidney function among individuals with diabetes. (Trial Registry no. ISRCTN 99175498).

Association between sedentary time and kidney function in community-dwelling elderly Japanese people

AIM

The aim of the present study was to evaluate the relationship between sedentary time and declines in kidney function among community-dwelling older adults.

METHODS

Participants comprised 10 242 community-dwelling older adults who were participating in the National Center for Geriatrics and Gerontology - Study of Geriatric Syndromes. Sedentary time was determined by asking participants to record the total amount of hours usually spent sitting each day, with values divided into quartiles of 0 to <4 h (reference), 4 to <6 h, 6 to <8 h and ≥8 h of sitting time per day. The estimated glomerular filtration rate was determined according to creatinine levels, and participants were classified into two categories: ≥60.0 or <60 mL/min/1.73 m² .

RESULTS

After multivariate adjustment, the highest quartiles of sedentary time showed a higher rate of kidney function decline than those in the lowest quartile (odds ratio 1.42, 95% CI 1.02-1.37). In addition, participants with a history of cancer (odds ratio 1.18, 95% CI 1.01-1.39) or hypertension (odds ratio 1.38; 95% CI 1.07-1.60) had significantly increased risks of kidney function decline in the highest sedentary time group, regardless of multivariate control. Furthermore, analyses showed an increased risk of kidney function decline for a history of both cancer and hypertension (odds ratio 2.02, 95% CI 1.08-3.80).

CONCLUSIONS

A higher level of sedentary time was associated with kidney function decline among community-dwelling older adults. Geriatr Gerontol Int 2017; 17: 730-736.

Adiposity measures, lean body mass, physical activity and mortality: NHANES 1999-2004

Background

Obesity and physical inactivity are major public health problems. We studied the associations between measures of adiposity, lean body mass, leisure time physical activity (LTPA), and death in those with and without chronic kidney disease (CKD).

Methods

Associations between body mass index (BMI), waist circumference (WC), percent body fat, lean body mass (assessed with Dual-Energy X-ray Absorptiometry[DEXA]), leisure time physical activity (LTPA) and death were examined using the National Health and Nutrition Examination Surveys (NHANES 1999–2004). All-cause mortality was ascertained by linkage of NHANES files with the National Death Index.

Results

9,433 non-CKD participants and 2,153 CKD participants who had fat mass measured using DEXA, BMI, WC, LTPA and mortality data were included. After adjusting for demographics, comorbid conditions, kidney function measures, C-Reactive Protein (CRP), and sodium intake there was no significant risk for death noted with higher WC, fat mass and BMI in those with and without CKD. When examining normal, overweight, and obese groups based on BMI criteria, being overweight (BMI 25–29.9 kg/m²) was associated with lower risk of death in those without CKD (Hazard ratio 0.62, 95% CI 0.40, 0.95). Higher lean body mass was associated with lower risk for death in those without kidney disease but not in the CKD population. There was a significantly higher risk for death among those who did not meet the minimum LTPA goals compared to those who met or exceeded the recommended activity levels (>450 MET/min/week) in those with and without CKD (CKD Hazard ratio: 1.36, 95% CI 1.003, 1.85; non-CKD HR 1.65, 95% CI 1.21, 2.26).

Conclusions

In a representative sample of the US population, higher LTPA levels and lean body mass were associated with lower mortality in those without kidney disease. In CKD, higher LTPA was associated with lower risk of death. There was no association between adiposity measures and death in those with and without CKD except for lower mortality associated with overweight among those without CKD. The data suggests the need to develop programs to facilitate an increase in physical activity in people with and without kidney disease.

Microalbuminuria, kidney function, and daily physical activity

The present study was carried out to investigate independent relationship between daily physical activity, microalbuminuria, and kidney function. The demographic characteristics and laboratory parameters were recorded for all patients. The determination of daily activities was carried out by Nottingham Extended Activities of Daily Living Scale (NEADLS) which was performed for each patient in an interview. Totally 139 patients were enrolled. In the whole group NEADLS score was correlated with age (rho: −0.759, P < 0.0001), clinical systolic blood pressure (rho: −0.212, P: 0.018), blood urea nitrogen (rho: −0.516, P < 0.0001), creatinine (rho: −0.501, P < 0.0001), uric acid (rho: −0.308, P < 0.0001), albumin (rho: 0.382, P < 0.0001), total cholesterol (rho: −0.194, P: 0.022), LDL-cholesterol (rho: −0.230, P: 0.008), hemoglobin (rho: 0.256, P: 0.002), creatinine clearance (rho: 0.565, P < 0.0001), 24-hour urinary protein excretion (rho: −0.324, P < 0.0001), and 24-hour urinary albumin excretion (UAE) (rho: −0.483, P < 0.0001). The multivariate linear regression of independent factors corelated with logarithmically converted NEADLS score (as a dependent variable) has shown that age (P < 0.0001), presence of coronary artery disease (P: 0.011), hemoglobin (P: 0.020), 24-hour creatinine clearance (P: 0.004), and 24-hour urinary albumin excretion (P < 0.0001) were independently corelated with NEADLS score. In conclusion, both UAE and kidney function were independently associated with daily physical activity.

The role of physical activity in chronic kidney disease in the presence of diabetes mellitus: a prospective cohort study

BACKGROUND/AIMS

Although the effect of exercise on health is well established, nephrologists seldom consider physical activity in the treatment of chronic kidney disease (CKD) or CKD in the presence of diabetes mellitus (DM/CKD). The aim of the present study was to analyze the benefits of leisure-time physical activity (LTPA) in DM/CKD.

METHODS

A total of 445,075 adult participants who underwent a medical screening program between 1996 and 2008 were prospectively recruited. Of these, 7,863 DM/CKD subjects were identified. Each participant was categorized according to LTPA level (a product of duration and intensity) as inactive, low-active or fully active. Hazard ratios (HRs) for mortality risk were calculated.

RESULTS

Fully active LTPA was associated with lower odds of DM/CKD development and lower risk of mortality among patients with DM/CKD in a dose-response relationship. The fully active and low-active DM/CKD groups had a 26% (HR 0.74, 95% CI 0.66-0.85) and 13% (HR 0.87, 95% CI 0.75-1.01) lower risk of all-cause mortality, respectively, in comparison to the inactive group. The association of exercise with mortality rate reduction was more pronounced among DM/CKD subjects (mortality rate reduction of 446.5 per 100,000 person-years) than among subjects with diabetes alone or CKD alone.

CONCLUSION

Exercise, at the recommended level or more, is associated not only with lower odds of DM/CKD but also with a 26% lower mortality risk among DM/CKD patients. Nephrologists should encourage all DM/CKD subjects to be physically active

Body mass index, waist circumference, physical activity, and risk of hearing loss in women

BACKGROUND

Acquired hearing loss is highly prevalent, but prospective data on potentially modifiable risk factors are limited. In cross-sectional studies, higher body mass index (BMI), larger waist circumference, and lower physical activity have been associated with poorer hearing, but these have not been examined prospectively.

METHODS

We examined the independent associations between BMI, waist circumference, and physical activity, and self-reported hearing loss in 68,421 women in the Nurses' Health Study II from 1989 to 2009. Baseline and updated information on BMI, waist circumference, and physical activity was obtained from biennial questionnaires.

RESULTS

After more than 1.1 million person-years of follow-up, 11,286 cases of hearing loss were reported to have occurred. Higher BMI and larger waist circumference were associated with increased risk of hearing loss. Compared with women with BMI <25 kg/m(2), the multivariate-adjusted relative risk (RR) for women with BMI ≥ 40 was 1.25 (95% confidence interval [CI], 1.14-1.37). Compared with women with waist circumference <71 cm, the multivariate-adjusted RR for waist circumference >88 cm was 1.27 (95% CI, 1.17-1.38). Higher physical activity was related inversely to risk; compared with women in the lowest quintile of physical activity, the multivariate-adjusted RR for women in the highest quintile was 0.83 (95% CI, 0.78-0.88). Walking 2 hours per week or more was associated inversely with risk. Simultaneous adjustment for BMI, waist circumference, and physical activity slightly attenuated the associations but they remained statistically significant.

CONCLUSIONS

Higher BMI and larger waist circumference are associated with increased risk, and higher physical activity is associated with reduced risk of hearing loss in women. These findings provide evidence that maintaining healthy weight and staying physically active, potentially modifiable lifestyle factors, may help reduce the risk of hearing loss.

Chronic kidney disease and cardiovascular risk: epidemiology, mechanisms, and prevention

Since the first description of the association between chronic kidney disease and heart disease, many epidemiological studies have confirmed and extended this finding. As chronic kidney disease progresses, kidney-specific risk factors for cardiovascular events and disease come into play. As a result, the risk for cardiovascular disease is notably increased in individuals with chronic kidney disease. When adjusted for traditional cardiovascular risk factors, impaired kidney function and raised concentrations of albumin in urine increase the risk of cardiovascular disease by two to four times. Yet, cardiovascular disease is frequently underdiagnosed and undertreated in patients with chronic kidney disease. This group of patients should, therefore, be acknowledged as having high cardiovascular risk that needs particular medical attention at an individual level. This view should be incorporated in the development of guidelines and when defining research priorities. Here, we discuss the epidemiology and pathophysiological mechanisms of cardiovascular risk in patients with chronic kidney disease, and discuss methods of prevention.

Association of low aerobic fitness with hyperfiltration and albuminuria in men

PURPOSE

The purpose of this study was to evaluate the association of low aerobic fitness (AF), a quantitative phenotype primarily modified by physical activity, with the earlier markers of chronic kidney disease (CKD).

METHODS

Maximum oxygen uptake (VO2max), the best index of AF, was estimated in an apparently healthy population of 34,769 adults without known history of diabetes and/or hypertension, and its association with renal function and albuminuria was analyzed retrospectively. VO2max was estimated using a cycle ergometer. Glomerular filtration rate was estimated with the Modification of Diet in Renal Disease Study equation. Glomerular hyperfiltration was defined as estimated glomerular filtration rate above the age- and sex-specific 97.5th percentile. Albuminuria was detected with dipstick urinalysis on fast morning urine and defined as ≥1+.

RESULTS

VO2max levels were negatively correlated with the odds ratios of glomerular hyperfiltration in men (Ptrend = 0.039), not in women. VO2max was associated with glomerular hyperfiltration in young men (≤ the median age; Ptrend < 0.001), but not in old men. VO2max levels were negatively correlated with the odds ratio of albuminuria in men (Ptrend < 0.001), but not in women. These findings suggest that low AF may be associated with earlier markers of CKD in men. This association was not observed in women.

CONCLUSION

From the results of this study, it can be concluded that low AF may be a possible independent, modifiable risk factor for CKD in men.

Lifestyle-related factors, obesity, and incident microalbuminuria: the CARDIA (Coronary Artery Risk Development in Young Adults) study

BACKGROUND

Modifiable lifestyle-related factors are associated with risk of coronary heart disease and may also influence kidney disease risk.

STUDY DESIGN

Community-based prospective cohort study.

SETTING & PARTICIPANTS

2,354 African American and white participants aged 28-40 years without baseline microalbuminuria or estimated glomerular filtration rate <60 mL/min/1.73 m² recruited from 4 US centers: Birmingham, AL; Chicago, IL; Minneapolis, MN; and Oakland, CA.

FACTORS

Current smoking, physical activity, fast food habits, obesity, and diet quality, which was based on 8 fundamental components of the Dietary Approaches to Stop Hypertension (DASH) diet, including increased intake of fruits, vegetables, low-fat dairy products, whole grains, and nuts and legumes and reduced intake of sodium, sugar-sweetened beverages, and red and processed meats.

OUTCOMES & MEASUREMENTS

Spot urine albumin-creatinine ratios were obtained at baseline (1995-1996) and three 5-year follow-up examinations (5, 10, and 15 years' follow-up). Incident microalbuminuria was defined as the presence of age- and sex-adjusted albumin-creatinine ratio ≥25 mg/g at 2 or more of the successive follow-up examinations.

RESULTS

During the 15-year follow-up, 77 (3.3%) individuals developed incident microalbuminuria. After multivariable adjustment, poor diet quality (OR, 2.0; 95% CI, 1.1-3.4) and obesity (OR, 1.9; 95% CI, 1.1-3.3) were associated significantly with microalbuminuria; current smoking (OR, 1.6; 95% CI, 0.9-2.8) was associated with microalbuminuria, although the CI crossed 1.0. Neither low physical activity (OR, 1.0; 95% CI, 0.5-1.8) nor fast food consumption (OR, 1.2; 95% CI, 0.7-2.3) was associated with microalbuminuria. Compared with individuals with no unhealthy lifestyle-related factors (poor diet quality, current smoking, and obesity), adjusted odds of incident microalbuminuria were 131%, 273%, and 634% higher for the presence of 1 (OR, 2.3; 95% CI, 1.3-4.3), 2 (OR, 3.7; 95% CI, 1.8-7.7), and 3 (OR, 7.3; 95% CI, 2.1-26.1) unhealthy lifestyle-related factors.

LIMITATIONS

Self-reported dietary history and physical activity, low number of outcomes.

CONCLUSIONS

Consuming an unhealthy diet and obesity are associated with incident microalbuminuria.

Overweight, obesity and intentional weight loss in chronic kidney disease: NHANES 1999-2006

Objective

Obesity and chronic kidney disease (CKD) have emerged as major public health problems. We aimed to examine: a) lifestyle and behavioral factors, b) factors related to pursuing weight loss, and c) weight loss modalities pursued by CKD and non-CKD individuals who are overweight and obese.

Methods

Cross-sectional analysis of 10,971 overweight and obese adult participants in the National Health and Nutrition Examination Surveys conducted between 1999-2006. We examined the differences in lifestyle and behavioral factors between CKD and non-CKD participants and factors associated with pursuing weight loss using survey regression models.

Results

The total daily energy intake of the CKD population was lower than the non-CKD group (1987 kcal/day vs. 2063 kcal/day, p=0.02) even after adjusting for relevant covariates. However, the percentage of energy derived from protein was similar between the groups. Sixty-six percent of the CKD population did not meet the minimum recommended leisure time physical activity goals compared to 57% among non-CKD (p<0.001). Fifty percent of CKD participants pursued weight loss (vs. 55% of non-CKD individuals, p=0.01), but the presence of CKD was not independently associated with the pursuit of weight loss in the multivariate model. Among participants pursuing weight loss, modalities including dietary interventions utilized by CKD and non-CKD participants were similar. Eight percent of CKD participants used medications to promote weight loss.

Conclusions

Among the overweight and obese population, lifestyle and behavioral factors related to obesity and weight loss are similar between CKD and non-CKD participants. Insufficient data exist on the beneficial effects of intentional weight loss in CKD and these data show that a significant proportion of the CKD population use diets that may have high protein content and medications to promote weight loss that may be harmful. Future clinical trials evaluating the efficacy and optimal modalities to treat obesity in the CKD population are warranted.

Physical activity, television viewing time, and retinal microvascular caliber: the multi-ethnic study of atherosclerosis

Physical activities and sedentary behaviors are 2 broad classes of behavior that may be clearly distinguished from each other and have different patterns of determinants. The authors examined the associations of physical activity and television viewing time with retinal vascular caliber among US adults (n = 5,893) from 4 racial/ethnic groups in the Multi-Ethnic Study of Atherosclerosis (2002-2004) that included non-Hispanic whites, blacks, Hispanics, and Chinese. Physical activity and television viewing time were assessed by using a questionnaire, and vascular calibers (arteriolar and venular) were measured from digital retinal photographs. Those in the lowest quartile of physical activity had wider retinal venular caliber compared with those in the highest quartile in multivariate models adjusted for demographic, cardiovascular, behavioral, and inflammatory risk factors. This was noted in non-Hispanic whites and Hispanics but not in blacks or Chinese. For television viewing time, non-Hispanic whites (but not the other racial/ethnic groups) who were in the highest quartile of television viewing time had wider retinal venular caliber compared with those in the lowest quartile. No associations were noted with arteriolar caliber. Lower levels of physical activity (among non-Hispanic whites and Hispanics) and higher levels of television viewing time (among whites) are associated with wider retinal venules.

Low-Intensity physical activity beneficially alters the ultrastructural renal morphology of spontaneously hypertensive rats

INTRODUCTION AND OBJECTIVE

Kidney disorders can cause essential hypertension, which can subsequently cause renal disease. High blood pressure is also common among those with chronic kidney disease; moreover, it is a well-known risk factor for a more rapid progression to kidney failure. Because hypertension and kidney function are closely linked, the present study aimed to observe the beneficial effects of low-intensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats.

METHOD

Male Wistar-Kyoto rats and spontaneously hypertensive rats were randomly allocated into four groups: sedentary or exercised Wistar-Kyoto and sedentary or exercised spontaneously hypertensive rats. The exercise lasted 20 weeks and consisted of treadmill training for 1 hour/day, 5 days/week.

RESULTS

The exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26%. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity: (i) the interdigitations of the proximal and distal convoluted tubules; (ii) the basal membrane of the proximal and distal convoluted tubules; and (iii) in the basal membrane, slit diaphragm and pedicels of the glomerular filtration barrier. The spontaneously hypertensive rats also showed a decreased expression of connexin-43.

CONCLUSION

Physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals.