Recent trends in the prevalence of chronic kidney disease in Korean adults: Korean National Health and Nutrition Examination Survey from 1998 to 2013

Trajectory Analysis in FBG and the Incidence of Chronic Kidney Disease: A Nationwide Population-Based Study

OBJECTIVES

This study aimed to classify fasting blood glucose (FBG) trajectories by sex and examine their associations with the risk of chronic kidney disease (CKD).

METHODS

Using data from the National Health Insurance Service-National Sample Cohort in Korea, participants aged 40 years and above, without CKD or diabetes mellitus (DM), were followed from 2002 to 2009. Based on their FBG trajectories, participants were categorized into two classes and stratified by sex. CKD incidence rates were analyzed according to these FBG trajectories, and the impact of additional risk factors on CKD incidence was assessed.

RESULTS

A total of 91,131 participants were analyzed. Among individuals classified in Class 1, FBG levels gradually increased from 90.7 (men) and 88.7 (women) in 2002 to 96.6 (men) and 93.2 (women) in 2009. In contrast, participants classified as Class 2 exhibited a rapid increase in FBG levels, rising from 106 (men) and 106 (women) in 2002 to 144 (men) and 132 (women) in 2009. The incidence of CKD increased over time in both men and women classified as Class 2 compared to Class 1, with respective hazard ratios (HR) of 1.35 for men and 1.53 for women. Additionally, increased age, hypertension, and body mass index (BMI) were independently associated with an elevated risk of CKD.

CONCLUSIONS

The Class 2 group demonstrated a significantly higher incidence of CKD compared to the Class 1 group. This finding indicates the need for the proactive management of individuals with relatively high FBG levels featuring rapid FBG increases in order to mitigate the risk of CKD development.

Identification and Functional Mechanism Verification of Novel MicroRNAs Associated with the Fibrosis Progression in Chronic Kidney Disease

Chronic kidney disease (CKD) is a serious threat to human health worldwide, and its incidence is increasing annually. A growing amount of information is emerging about the role of micoRNAs (miRNAs) in the regulation of renal fibrosis, which has aroused interest in the development of drugs that block pathogenic miRNAs or restore protective miRNAs levels. To clarify the role of miRNAs in CKD, we selected patients with significant renal fibrotic disease (diabetic nephropathy (DN) and focal segmental glomerulosclerosis (FSGS)) as the disease group, and patients with little or no renal fibrotic disease (minimal change disease (MCD) and renal carcinoma adjacent to normal kidney) as controls. Significantly differentially expressed miRNAs were obtained by human kidney tissue sequencing, subsequently verified in mice models of DN and FSGS, and subsequently inhibited or overexpressed in human renal tubular epithelial cells (HK-2) stimulated by high glucose (HG) and TGF-β1 in vitro. Therefore, the mechanism of its action in renal fibrosis was further elaborated. Finally, the downstream target genes of the corresponding miRNAs were verified by bioinformatics analysis, qRT-PCR, western blot and double luciferase report analysis. Two novel miRNAs, hsa-miR-1470-3p (miR-1470) and hsa-miR-4483-3p (miR-4483), were detected by renal tissue sequencing in the disease group with significant renal fibrosis (DN and FSGS) and the control group with little or no renal fibrosis (MCD and normal renal tissue adjacent to renal carcinoma). Subsequent human renal tissue qRT-PCR verified that the expression of miR-1470 was significantly increased, while the expression of miR-4483 was markedly decreased in the disease group (p < 0.05). Moreover, in vivo DN and FSGS mice models, the expression levels of miR-1470 and miR-4483 were consistent with the results of human kidney tissue. In vitro, miR-4483 was suppressed, whereas miR-1470 was induced by treatment with TGF-β1 or HG. Inhibition of miR-1470 or overexpression of miR-4483 promoted HG or TGF-β1-induced fibrosis in HK-2 cells. Further study revealed that MMP-13 and TIMP1 were the target genes ofmiR-1470 and miR-4483, respectively. Our study identifies newly dysregulated miRNA profiles related to fibrosis kidneys. miR-1470 and miR-4483 are demonstrated to participate in kidney fibrosis by regulation of MMP-13, TIMP1 respectively. Our results may represent a promising research direction for renal disorders and help identify new biomarkers and therapeutic targets for CKD.

Assessment of the renal function and fibrosis indexes of conventional western medicine with Chinese medicine for dredging collaterals on treating renal fibrosis: A systematic review and meta-analysis

To investigate the renal function and fibrosis indexes of conventional western medicine with Chinese medicine for dredging collaterals in the treatment of renal fibrosis (RF). We searched articles from databases (PubMed, Embase, The Cochrane Library, CNKI, and Wanfang data) and references of included studies. The quality of literature was evaluated and data were extracted in regard to the inclusion and exclusion criteria. RevMan5.3 software was applied for all statistical analyses. Eleven eligible RCTs with a total of 898 patients were included in this meta-analysis. Compared with conventional western medicine alone, conventional western medicine with Chinese medicine for dredging collaterals in the treatment of RF has lower BUN levels and SCr levels (P < 0.05). As for fibrosis indexes, conventional western medicine with Chinese medicine for dredging collaterals has lower HA, laminin (LN), IV-Col, and PC-III levels (P < 0.05). Conventional western medicine with Chinese medicine for dredging collaterals with lower BUN, Scr, HA, LN, PC-III, and IV-Col levels, has an advantage in the treatment of RF. These lower serum levels may not be associated with the presence of RF. Ideally, kidney biopsies should be performed to confirm that these markers reduce RF. This is a major limitation of this study.

Sex-related differences in pre-dialysis trajectories and dialysis initiation: A French nationwide retrospective study

BACKGROUND

In the last two decades, sex and gender differences have been documented in chronic kidney disease (CKD) management, including access to renal replacement therapy and its outcomes. The objectives of this study were to 1) compare the pre-dialysis healthcare utilization in men and women, and 2) examine the sex-specific factors associated with emergency dialysis start.

METHODS

Adult patients with CKD who started dialysis in France in 2015 were extracted from the Renal Epidemiology and Information Network registry. Patients were matched to the French National Health Data System database to extract healthcare utilization data for the 2 years before dialysis start. Frequencies and monthly rates of consultations and hospitalizations were compared between men and women. Logistic regression analyses were performed separately in the two groups.

RESULTS

Among the 8856 patients included, 3161 (35.7%) were women. Median age (71 years) and estimated glomerular filtration rate (8.1 and 7.7 ml/min for men and women) were similar between groups at dialysis start. Monthly consultations rates with a general practitioner and nephrology-related care were similar between women and men. Some sex-specific differences were found: higher frequencies of consultations with a psychiatrist in women and more frequent hospitalizations for circulatory system diseases in men. Emergency dialysis start rate was 30% in both groups. Emergency dialysis start was associated with acute nephropathy, compared with slowly progressive nephropathy, in women but not in men (OR = 1.48, p<0.01 vs 1.15, p = 0.18).

CONCLUSIONS

This study found similar quantitative pre-dialysis healthcare utilization in men and women. To better understand sex/gender differences in CKD care trajectories, future research should focus on patients with CKD who are unknown to nephrology services, on patients receiving conservative care and on the sex/gender-specific mechanisms underlying care decision-making.

Prevalence of chronic kidney disease and metabolic related indicators in Mianzhu, Sichuan, China

Background

Chronic kidney disease (CKD) is a major public health problem worldwide. Periodic surveys are essential for monitoring the prevalence of CKD and its risk factors. We assessed the prevalence of CKD and its risk factors in Mianzhu City in 2020.

Method

The Natural Population Cohort Study surveyed 7,770 individuals aged>20 years in Mianzhu City of Sichuan province in 2020. Our investigation encompassed the measurement of CKD prevalence, the evaluation of various renal function indicators, and comparisons based on age, gender, and hukou status. Additionally, some metabolic indices were also measured to identify the underlying causes of CKD.

Results

(1) Overall, the prevalence of reduced renal function (eGFR<60 mL/min/1.73m2), albuminuria, and CKD were 1.3, 10.0, and 10.4%, respectively, (2) the overall prevalence of CKD was higher among men than among women (14.5% vs. 8.6%). Similarly, the prevalence of CKD was higher among men than women in most age groups, (3) among urban residents, the prevalence of CKD was higher among middle-aged individuals and lower among young individuals and older adults, and (4) considering eGFR, the albuminuria and CKD for group definition, Blood pressure, triglyceride, high-density lipoprotein, blood sugar, and BMI were all statistically different among between normal groups and abnormal groups s in the albuminuria and CKD.

Conclusion

The incidence of CKD greatly varied between Mianzhu City and other regions in China and other countries. The differences in risk factors of CKD should be explored in the future. The gender difference in the prevalence of CKD in this study was markedly different from that in previous studies. More high-quality studies are needed to further explore this controversy. Based on the different prevalence of CKD and metabolism-related indices in rural and urban areas in this study, we speculated that the high incidence of CKD in Mianzhu City might be related to diet, lifestyle, and availability of healthcare services.

Sex disparity in dialysis and kidney transplantation over 20 years in Korea

BACKGROUND

Sex disparity is prevalent in organ transplantations worldwide. This study aimed to understand sex disparities in dialysis and kidney transplantation in Korea over the last 20 years.

METHODS

Data for incident dialysis, waiting list registration, and donors and recipients were retrospectively collected between January 2000 and December 2020 from the Korean Society of Nephrology end-stage renal disease registry and the database of the Korean Network for Organ Sharing. Data regarding the proportion of females for dialysis, waiting list, and kidney transplantation donors or recipients were analyzed using linear regression analysis.

RESULTS

The average proportion of females on dialysis over the past 20 years was 40.5%. The proportion of females on dialysis was 42.8% in 2000, and decreased to 38.2% in 2020, showing a decreasing trend. The average proportion of women on the waiting list was 38.4%, which was lower than that for dialysis. The average proportion of female recipients in living donor kidney transplantation and female living donors were 40.1% and 53.2%, respectively. The overall proportion of female donors in living donor kidney transplantation showed an increasing trend. However, there was no change in the proportion of female recipients in living donor kidney transplantation.

CONCLUSION

Sex disparities in organ transplantation exist, including an increasing trend of female donors in living donor kidney transplantation. Further studies are needed to identify the biological and socioeconomic factors involved to resolve these disparities.

National trends in the prevalence of chronic kidney disease among Korean adults, 2007-2020

Little is known about the prevalence of chronic kidney disease (CKD) during the coronavirus disease 2019 (COVID-19) pandemic. We aimed to investigate the long-term trends in CKD prevalence from South Korea including the early pandemic. We used data from 108,152 Korean adults from 2007 to 2020 obtained from a representative longitudinal serial study. We defined CKD as a condition when the participant's estimated glomerular filtration rate was < 60 mL/min/1.73 m², or one-time spot proteinuria was ≥ 1 +, and then examined the overall trends in the prevalence of CKD. Among the included adults (n = 80,010), the overall national prevalence of CKD was 6.2%. The trend slope gradually increased from 2007 to 2019, however, there was a sudden decrease in 2020 (2007-2010, 5.1% [95% confidence interval (CI) 4.7-5.5]; 2017-2019, 7.1% [95% CI 6.6-7.6]; pandemic period, 6.5% [95% CI 5.7-7.3]; and β_diff, - 0.19; 95% CI - 0.24 to - 0.13). The prevalence of CKD among younger adults and those with poor medical utilization significantly decreased during the early pandemic. This study was the first large-scale study to investigate the longitudinal prevalence of CKD from 2007 to 2020. Further research is needed to fully understand the exact causes for this decline and to identify healthcare policy strategies for preventing and managing CKD.

Chronic kidney disease is more prevalent among women but more men than women are under nephrological care : Analysis from six outpatient clinics in Austria 2019

BACKGROUND

A discrepancy between sex-specific treatment of kidney failure by dialysis (higher in men) and the prevalence of chronic kidney disease in the general population (higher in women) has been reported internationally, but the prevalence by sex has not been described for Austria. Sex disparity among nephrology outpatients has not been studied.

METHODS

We employed two formulae (2009 CKD-EPI suppressing the race factor, and race-free 2021 CKD-EPI) to estimate the sex distribution of CKD in Austrian primary care, based on creatinine measurements recorded in a medical sample of 39,800 patients from general practitioners' offices (1989-2008). Further, we collected information from all clinic appointments scheduled at nephrology departments of 6 Austrian hospitals (Wien, Linz, Wels, St. Pölten, Villach, Innsbruck) during 2019 and calculated visit frequencies by sex.

RESULTS

Using the 2009 CKD-EPI formula, the prevalence of CKD in stages G3-G5 (estimated glomerular filtration rate < 60 mL/min/1.73 m²) was 16.4% among women and 8.5% among men aged > 18 years who had attended general practitioners' offices in Austria between 1989 and 2008 and had at least one creatinine measurement performed. Using the 2021 CKD-EPI formula, the respective CKD prevalence was 12.3% among women and 6.1% among men. In 2019, 45% of all outpatients at 6 participating nephrology departments were women. The median of nephrology clinic visits in 2019 was two (per year) for both sexes.

CONCLUSION

CKD is more prevalent among Austrian women than men. Men are more prevalent in nephrology outpatient services. Research into causes of this sex disparity is urgently needed.

The ratio of triglycerides to high-density lipoprotein cholesterol is associated with the risk of chronic kidney disease in Korean men

Dyslipidemia is nephrotoxic and can result in the development of chronic kidney disease (CKD). The ratio of triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) (TG/HDL-C ratio) is well-correlated with insulin resistance and cardiovascular events. The aim of this study is to examine the association between the TG/HDL-C ratio and CKD in Korean adults. This study was retrospectively designed based on the National Health Insurance Service-National Health Screening cohort. Seventy three thousand and fifty-two participants aged between 40 and 79 years old at baseline (2009-2010) were included in the final analyses. The study population was classified into three tertile groups (T₁ , T₂ , and T₃ ) according to the TG/HDL-C ratio by sex. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for CKD were calculated using Cox proportional hazard regression models. The median follow-up duration was 5.9 years. Higher tertile groups of the TG/HDL-C ratio had lower estimated glomerular filtration rates in both sexes. The cumulative incidence of CKD of T₁ , T₂ , and T₃ was 11.89%, 12.90%, and 12.91%, respectively, in men and 10.17%, 10.61%, and 14.87%, respectively, in women (all p values < 0.001). Compared with T₁ of the TG/HDL-C ratio, the HRs (95% CIs) of T₂ and T₃ for CKD were 1.212 (1.118-1.315) and 1.183 (1.087-1.287), respectively, in men and 0.895 (0.806-0.994) and 1.038 (0.937-1.150), respectively, in women after being fully adjusted. Higher TG/HDL-C ratios were positively associated with CKD development in men, while middle levels of TG/HDL ratios reduced the CKD incidence in women.

Epidemiology of chronic kidney disease in Peru and its relation to social determinants of health

BACKGROUND

Chronic kidney disease (CKD) is a growing public health problem and an important cause of morbidity and mortality. Disparities in CKD may be related to social determinants and health inequalities in low- and middle-income countries. This study determined how social determinants of health influence trends in the prevalence and mortality of CKD in Peru.

METHODS

This was an ecological study based on a secondary analysis of health care and death records obtained from the Ministry of Health of Peru for the period 2010-2016. The standardized prevalence and mortality rates of CKD were descriptively reported using geospatial exploratory analysis. We also determined the association with social determinants of health according to the domains suggested by Healthy People 2020.

RESULTS

In the studied period, CKD prevalence increased by 300% and was associated with the health insurance coverage rate (β=5.9 [95% CI 0.82 to 10.92]), proportion of people with a secondary education level (β=11.4 [95% CI 1.94 to 20.93]), mean age (β=-10.7 [95% CI -19.33 to -2.12]), monetary poverty rate (β=-2.2 [95% CI -3.88 to -0.60]) and gross domestic product per capita (β=-63.2 [95% CI -117.81 to -8.52]). The standardized mortality decreased by 10% and was associated with mean age (β=-0.6 [95% CI -1.22 to -0.06]) and the proportion of people with a primary education level (β=-0.5 [95% CI -0.9 to -0.05]).

CONCLUSIONS

During the period 2010-2016, the prevalence of CKD increased and the mortality associated with CKD decreased. The observed changes were associated with some social determinants of health, such as increased health coverage and education. The health system of Peru must be prepared to take on the challenge.

Estimating disease prevalence from drug utilization data using the Random Forest algorithm

Background

Aggregated claims data on medication are often used as a proxy for the prevalence of diseases, especially chronic diseases. However, linkage between medication and diagnosis tend to be theory based and not very precise. Modelling disease probability at an individual level using individual level data may yield more accurate results.

Methods

Individual probabilities of having a certain chronic disease were estimated using the Random Forest (RF) algorithm. A training set was created from a general practitioners database of 276 723 cases that included diagnosis and claims data on medication. Model performance for 29 chronic diseases was evaluated using Receiver-Operator Curves, by measuring the Area Under the Curve (AUC).

Results

The diseases for which model performance was best were Parkinson’s disease (AUC = .89, 95% CI = .77–1.00), diabetes (AUC = .87, 95% CI = .85–.90), osteoporosis (AUC = .87, 95% CI = .81–.92) and heart failure (AUC = .81, 95% CI = .74–.88). Five other diseases had an AUC >.75: asthma, chronic enteritis, COPD, epilepsy and HIV/AIDS. For 16 of 17 diseases tested, the medication categories used in theory-based algorithms were also identified by our method, however the RF models included a broader range of medications as important predictors.

Conclusion

Data on medication use can be a useful predictor when estimating the prevalence of several chronic diseases. To improve the estimates, for a broader range of chronic diseases, research should use better training data, include more details concerning dosages and duration of prescriptions, and add related predictors like hospitalizations.

Association between lifestyle factors and decreased kidney function in older adults: a community-based cross-sectional analysis of the Taipei City elderly health examination database

BACKGROUND

Impaired kidney function is the hallmark of chronic kidney disease (CKD), and is associated with increased risk of all-cause mortality in the elderly. In the present cross-sectional population-based study, we aimed to evaluate the associations between lifestyle factors (exercise habit, alcohol consumption, smoking history, and betel nut chewing) and decreased kidney function.

METHODS

The data from the Taipei City Elderly Health Examination Database (2006 to 2012) were extracted. Associations between risk factors and reduced estimated Glomerular filtration rate (eGFR) were evaluated by regression and stratification analyses.

RESULTS

A total of 297,603 participants were included in the final analysis, and 29.7% of them had reduced eGFR. Smoking was significantly associated with an elevated risk of reduced eGFR. While, physical exercise conferred to a significantly decreased adjusted odds ratio (aOR) in reduced eGFR (regular exercise, aOR = 0.79; occasional exercise, aOR = 0.87). Furthermore, the protective effect of exercise habit against reduced eGFR was not affected by comorbid conditions, such as hypertension, diabetes, obesity, and cardiovascular disease.

CONCLUSIONS

Engaging in physical exercise was beneficially associated with reduced eGFR in older individuals. Longitudinal or prospective studies are warranted for confirmation and extrapolation of the current findings.

Sex hormones and their influence on chronic kidney disease

PURPOSE OF REVIEW

The majority of end-stage renal disease including dialysis and kidney transplant patients are men. In contrast, the incidence of chronic kidney disease (CKD) is higher in women compared with men. In this review, we dissect the sex hormone levels and its effects on experimental models and patients with CKD.

RECENT FINDINGS

Sex hormones are clearly involved in CKD progression to end-stage renal disease (ESRD). A significant reduction in lipid peroxidation as a mechanism of renoprotection has been observed in kidneys of streptozotocin (STZ)-diabetic ovariectomized rats after estradiol administration. Furthermore, a G-protein-coupled estrogen receptor inhibits podocyte oxidative stress maintaining the integrity of the mitochondrial membrane. Sex hormone depletion has been shown to modulate RAS system and protect against kidney injury in the male STZ-diabetic model. In human primary proximal tubular epithelial cells, a proteomic study showed that dihydrotestosterone dysregulated metabolic, suggesting that the deleterious effect of androgens within the kidney maybe related to altered energy metabolism in renal tubules.

SUMMARY

Male gender is associated with worse CKD progression and this fact may be ascribed to sex hormone. Although male hormones exert a deleterious effect in terms of increasing oxidative stress, activating RAS system, and worsening fibrosis within the damaged kidney, female hormones exert a renoprotective effect.

Older menarche age and short reproductive period linked to chronic kidney disease risk

This study aimed to investigate the association between reproductive period and menarche age and chronic kidney disease (CKD) in South Korean postmenopausal women.This was a cross-sectional study of the data for 8510 postmenopausal women using the results of Korean National Health and Nutrition Examination Surveys over the past 6 years.Of the total 8510 postmenopausal women, 790 (10.23%) were CKD patients. The menarche age in the CKD group was 16.2 ± 1.9 years old, which was higher than that in the non-CKD group (P < .001). The reproductive period of the CKD group was 32.4 ± 5.7 years, which was shorter than 33.3 ± 5.4 years in the non-CKD group (P < .001). The prevalence of CKD was 4.7% at a menarche age of 11 years or younger, which increased with increasing of menarche age, reaching 9.9% at menarche age of 16 years or older. According to the length of the reproductive period, the prevalence of CKD was 13.9% for the group less than 20 years of period and decreased significantly with increasing length of reproductive period. The prevalence of proteinuria was 7.2% in women with reproductive period of less than 20 years and significantly less in women with a reproductive period longer than 45 years (2.3%). The prevalence of CKD and proteinuria increased with increasing of menarche age, and the prevalence of CKD and proteinuria decreased with increasing of reproductive period.The results suggest that CKD was associated with older menarche age and a short reproductive period. Management of life patterns and medical problems in women with old age at menarche and a short reproductive period should be considered.

Chronic kidney disease in neurogenic bladder

AIM

It was believed that neurogenic bladder (NB) might be a risk factor of chronic kidney disease (CKD). However, data are limited regarding the real incidence or risk of CKD in NB. In addition, serum creatinine (sCr), a classical marker of renal function, is not reliable in NB patients because they present muscle wasting due to disuse or denervation. The aim of the study was to estimate the prevalence of CKD in NB patients using serum Cystatin-C. Secondly, we aimed to identify the risk factors for CKD development in NB.

METHODS

This was a cross-sectional study in a public hospital, a specialized center for patients who were victims of industrial accidents. Serum Cystatin-C was checked at the regular laboratory test in the structured NB programme of the hospital, and 313 patients were included in the study.

RESULTS

The overall prevalence of CKD, defined as estimated glomerular filtration rate (eGFR) <60/mL per 1.73m² was 8.0% and 22.4%, by sCr-based and Cystain-C-based eGFR, respectively, and was greater than age-matched general population in Korea. sCr was not able to detect the early deterioration of renal function in NB patients. Co-morbid diabetes, small bladder volume, recurrent urinary tract infection, and proteinuria were significantly associated with CKD in the multivariable analysis.

CONCLUSION

Chronic kidney disease prevalence was more than three times higher in NB patients than in the general population despite recent progress in the medical care of NB. Co-morbid diabetes, small bladder volume, recurrent urinary tract infection, and proteinuria seem to be the risk factors for CKD development in NB.

The Association between Socioeconomic Status and Adherence to Health Check-up in Korean Adults, Based on the 2010-2012 Korean National Health and Nutrition Examination Survey

Background

We investigated the association between socioeconomic status and adherence to health check-ups in a Korean population aged 40 years or older.

Methods

This cross-sectional study included 12,311 participants who participated in the 2010–2012 Korean National Health and Nutrition Examination Survey. Self-reported questionnaires were used to assess each participant's socioeconomic status (household income, occupation, and education) and adherence to health check-ups.

Results

Men with a higher income (highest vs. lowest: odds ratio [OR], 1.799; 95% confidence interval [CI], 1.296–2.497) and men with a higher education level (≥12 vs. <6 years: OR, 1.488; 95% CI, 1.078–2.054) and office workers compared with manual workers (men: OR, 1.431; 95% CI, 1.077–1.902; women: OR, 1.783; 95% CI, 1.256–2.532) appeared to undergo more health check-ups. In particular, men and women with a higher income and education appeared more likely to undergo opportunistic health check-ups (men: highest vs. lowest income: OR, 2.380; 95% CI, 1.218–4.653; ≥12 vs. <6 years education: OR, 2.121; 95% CI, 1.142–3.936; women: highest vs. lowest income: OR, 4.042; 95% CI, 2.239–7.297; ≥12 vs. <6 years education: OR, 2.475; 95% CI, 1.283–4.775).

Conclusion

A higher socioeconomic status was associated with a higher rate of participation in health check-ups. More efforts are needed to identify the factors associated with disparity in adherence to health check-ups.

Oxidative Stress and Renal Fibrosis: Recent Insights for the Development of Novel Therapeutic Strategies

Chronic kidney disease (CKD) is a significant worldwide healthcare problem. Regardless of the initial injury, renal fibrosis is the common final pathway leading to end stage renal disease. Although the underlying mechanisms are not fully defined, evidence indicates that besides inflammation, oxidative stress plays a crucial role in the etiology of renal fibrosis. Oxidative stress results from an imbalance between the production of free radicals that are often increased by inflammation and mitochondrial dysfunction, and reduced anti-oxidant defenses. Several studies have demonstrated that oxidative stress may occur secondary to activation of transforming growth factor β1 (TGF-β1) activity, consistent with its role to increase nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) activity. A number of other oxidative stress-related signal pathways have also been identified, such as nuclear factor erythroid-2 related factor 2 (Nrf2), the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP)-cGMP-dependent protein kinase 1-phosphodiesterase (cGMP-cGK1-PDE) signaling pathway, and the peroxisome proliferator-activated receptor gamma (PPARγ) pathway. Several antioxidant and renoprotective agents, including cysteamine bitartrate, epoxyeicosatrienoic acids (EETs), and cytoglobin (Cygb) have demonstrated ameliorative effects on renal fibrosis in preclinical or clinical studies. The mechanism of action of many traditional Chinese medicines used to treat renal disorders is based on their antioxidant properties, which could form the basis for new therapeutic approaches. This review focuses on the signaling pathways triggered by oxidative stress that lead to renal fibrosis and provides an update on the development of novel anti-oxidant therapies for CKD.

Sex and gender disparities in the epidemiology and outcomes of chronic kidney disease

Improved understanding of sex and gender-specific differences in the aetiology, mechanisms and epidemiology of chronic kidney disease (CKD) could help nephrologists better address the needs of their patients. Population-based studies indicate that CKD epidemiology differs by sex, affecting more women than men, especially with regard to stage G3 CKD. The effects of longer life expectancy on the natural decline of glomerular filtration rate (GFR) with age, as well as potential overdiagnosis of CKD through the inappropriate use of GFR equations, might be in part responsible for the greater prevalence of CKD in women. Somewhat paradoxically, there seems to be a preponderance of men among patients starting renal replacement therapy (RRT); the protective effects of oestrogens in women and/or the damaging effects of testosterone, together with unhealthier lifestyles, might cause kidney function to decline faster in men than in women. Additionally, elderly women seem to be more inclined to choose conservative care instead of RRT. Dissimilarities between the sexes are also apparent in the outcomes of CKD. In patients with predialysis CKD, mortality is higher in men than women; however, this difference disappears for patients on RRT. Although access to living donor kidneys among men and women seems equal, women have reduced access to deceased donor transplantation. Lastly, health-related quality of life while on RRT is poorer in women than men, and women report a higher burden of symptoms. These findings provide insights into differences in the underlying pathophysiology of disease as well as societal factors that can be addressed to reduce disparities in access to care and outcomes for patients with CKD.

Sex and gender disparities in the epidemiology and outcomes of chronic kidney disease

Improved understanding of sex and gender-specific differences in the aetiology, mechanisms and epidemiology of chronic kidney disease (CKD) could help nephrologists better address the needs of their patients. Population-based studies indicate that CKD epidemiology differs by sex, affecting more women than men, especially with regard to stage G3 CKD. The effects of longer life expectancy on the natural decline of glomerular filtration rate (GFR) with age, as well as potential overdiagnosis of CKD through the inappropriate use of GFR equations, might be in part responsible for the greater prevalence of CKD in women. Somewhat paradoxically, there seems to be a preponderance of men among patients starting renal replacement therapy (RRT); the protective effects of oestrogens in women and/or the damaging effects of testosterone, together with unhealthier lifestyles, might cause kidney function to decline faster in men than in women. Additionally, elderly women seem to be more inclined to choose conservative care instead of RRT. Dissimilarities between the sexes are also apparent in the outcomes of CKD. In patients with predialysis CKD, mortality is higher in men than women; however, this difference disappears for patients on RRT. Although access to living donor kidneys among men and women seems equal, women have reduced access to deceased donor transplantation. Lastly, health-related quality of life while on RRT is poorer in women than men, and women report a higher burden of symptoms. These findings provide insights into differences in the underlying pathophysiology of disease as well as societal factors that can be addressed to reduce disparities in access to care and outcomes for patients with CKD.

Inflammation and renal fibrosis: Recent developments on key signaling molecules as potential therapeutic targets

Chronic kidney disease (CKD) is a major public health issue. At the histological level, renal fibrosis is the final common pathway of progressive kidney disease irrespective of the initial injury. Considerable evidence now indicates that renal inflammation plays a central role in the initiation and progression of CKD. Some of the inflammatory signaling molecules involved in CKD include: monocyte chemoattractant protein-1 (MCP-1), bradykinin B₁ receptor (B₁R), nuclear factor κB (NF-κB), tumor necrosis factor-α (TNFα), transforming growth factor β (TGF-β), and platelet-derived growth factor (PDGF). Multiple antifibrotic factors, such as interleukin-10 (IL-10), interferon-γ (IFN-γ), bone morphogenetic protein-7 (BMP-7), hepatocyte growth factor (HGF) are also downregulated in CKD. Therefore, restoration of the proper balance between pro- and antifibrotic signaling pathways could serve as a guiding principle for the design of new antifibrotic strategies that simultaneously target many pathways. The purpose of this review is to summarize the existing body of knowledge regarding activation of cytokine pathways and infiltration of inflammatory cells as a starting point for developing novel antifibrotic therapies to prevent progression of CKD.

Therapeutic potential of microRNAs for the treatment of renal fibrosis and CKD

Chronic kidney disease (CKD), defined as reduced glomerular filtration rate, is increasingly becoming a major public health issue. At the histological level, renal fibrosis is the final common pathway leading to end-stage renal disease, irrespective of the initial injury. According to this view, antifibrotic agents should slow or halt the progression of CKD. However, due to multiple overlapping pathways stimulating fibrosis, it has been difficult to develop antifibrotic drugs that delay or reverse the progression of CKD. MicroRNAs (miRNAs) are small noncoding RNA molecules, 18-22 nucleotides in length, that control many developmental and cellular processes as posttranscriptional regulators of gene expression. Emerging evidence suggests that miRNAs targeted against genes involved in renal fibrosis might be potential candidates for the development of antifibrotic therapies for CKD. This review will discuss some of the miRNAs, such as Let-7, miR-21,-29, -192, -200,-324, -132, -212, -30, -126, -433, -214, and -199a, that are implicated in renal fibrosis and the potential to exploit these molecular targets for the treatment of CKD.