Viral hepatitis and proteinuria in an area endemic for hepatitis B and C infections: another chain of link?

Hepatitis B virus infection as a risk factor for chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Currently, several studies have observed that chronic hepatitis B virus infection is associated with the pathogenesis of kidney disease. However, the extent of the correlation between hepatitis B virus infection and the chronic kidney disease risk remains controversial.

METHODS

In the present study, we searched all eligible literature in seven databases in English and Chinese. The random effects model was used to conduct a meta-analysis. Quality of included studies was assessed using the Newcastle-Ottawa Quality Scale.

RESULTS

In this analysis, a total of 31 studies reporting the association between hepatitis B virus infection and chronic kidney disease risk were included. The results showed a significant positive association between hepatitis B virus infection and the risk of chronic kidney disease (pooled OR, 1.20; 95% CI, 1.12-1.29), which means that hepatitis B virus increases the risk of developing chronic kidney disease.

CONCLUSION

This study found that hepatitis B virus infection was associated with a significantly increased risk of chronic kidney disease. However, the current study still cannot directly determine this causal relationship. Thus, more comprehensive prospective longitudinal studies are needed in the future to provide further exploration and explanation of the association between hepatitis B virus and the risk of developing chronic kidney disease.

Hepatitis C virus antibody seropositivity is associated with albuminuria but not peripheral artery disease in patients with type 2 diabetes

Hepatitis C virus (HCV) infection is prevalent in patients with type 2 diabetes mellitus (DM). We aimed to investigate whether HCV antibody (Ab) seropositivity is associated with diabetic micro- and macro-vascular diseases. In this hospital-based cross-sectional study, we retrospectively collected data from patients who participated in the diabetes pay-for-performance program and underwent HCV Ab screening in the annual comprehensive assessment between January 2021 and March 2022. We examined the relationships of HCV Ab seropositivity with the spot urinary albumin-to-creatinine ratio (UACR) and ankle-brachial index (ABI) in patients aged ≥ 50 years with type 2 DM. A total of 1758 patients were enrolled, and 85 (4.83%) of the enrolled patients had HCV Ab seropositivity. Multivariable regression analyses revealed that albuminuria showed a dose-dependent association with HCV Ab seropositivity (UACR [30-299 mg/g]: odds ratio [OR] = 1.463, 95% confidence interval [CI] 0.872‒2.456); UACR [≥ 300 mg/g]: OR = 2.300, 95% CI 1.160‒4.562; P for trend = 0.015) when compared with normal albuminuria (UACR < 30 mg/g). However, the proportion of patients with peripheral arterial disease, defined as an ABI ≤ 0.9, was not significantly different between the groups with and without HCV Ab seropositivity (3.5% vs. 3.9%, P = 0.999). In conclusion, severely increased albuminuria, but not the ABI, showed a significant association with HCV Ab seropositivity in patients aged ≥ 50 years with type 2 DM.

Focal Segmental Glomerulosclerosis Followed by Acute Hepatitis A Infection: Case Report

Background and Objectives: Chronic viral hepatitis such as hepatitis B or hepatitis C is frequently related to nephropathies, yet acute hepatitis A virus (HAV) infection is an exception. Materials and Methods: A 43-year-old male presented with jaundice accompanied by nausea and vomiting. The patient was diagnosed with acute HAV infection. Although the liver function improved after conservative treatment, various symptoms such as proteinuria, hypoalbuminemia, generalized edema and pleural effusion persisted. Due to nephrotic syndrome, the patient was referred to the clinic of the nephrology department and a renal biopsy was performed. Results: The result of the renal biopsy was focal segmental glomerulosclerosis (FSGS) based on histology, electron microscopy and immunohistochemistry. Therefore, based on the clinical history and biopsy results, the patient was diagnosed as having FSGS aggravated by acute HAV infection. Proteinuria, hypoalbuminemia and generalized edema were improved after prednisolone treatment. Conclusions: Although less common, acute HAV infection can also present with an extrahepatic manifestation, for example, FSGS. Hence, clinical attention is required if proteinuria or hypoalbuminemia persists in patients with acute HAV infection.

Long-term risk of end-stage renal diseases with maintenance dialysis among chronic hepatitis C patients after antiviral therapy in Taiwan

BACKGROUND AND AIM

Chronic hepatitis C virus (HCV) infection is associated with impaired renal function. The aim of this study is to explore the risk of and factors associated with end-stage renal diseases (ESRD) under maintenance dialysis among HCV patients after anti-HCV therapy.

METHODS

A total of 12 696 HCV-infected patients with interferon-based therapy, including 9679 (76.2%) achieving sustained virological response (SVR), were enrolled from 23 hospitals in Taiwan.

RESULTS

During a mean follow-up period of 5.3 years (67 554 person-years), the annual incidence of 4.1/10 000 person-years, 4.0/10 000 and 4.7/10 000 person-years among SVR patients and non-SVR patients, respectively. History of diabetes and baseline estimated glomerular filtration rate < 60 mL/min/m² , instead of SVR, were the significant risk factors for developing ESRD with maintenance dialysis after anti-HCV therapy (adjusted hazard ratio 7.75 and 9.78).

CONCLUSION

Diabetes and baseline impaired renal function were strongly associated with progression to ESRD with maintenance dialysis among chronic HCV-infected patients after antiviral therapy.

HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified.

AIM

We evaluated the impact of infection with HBV on the risk of CKD in the general population.

MATERIAL AND METHODS

We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed.

RESULTS

We retrieved 33 studies (n = 7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n = 1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P < .001). Between-study heterogeneity was noted (Q value, 49.5, P < .0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n = 3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P = .5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P < .015).

CONCLUSIONS

It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Evolutionary seroepidemiology of viral hepatitis and the gap in hepatitis C care cascades among uraemic patients receiving haemodialysis in Taiwan-the Formosa-Like Group

Uraemic patients undergoing haemodialysis are at high risk of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. We aimed to evaluate the evolutionary seroprevalence of viral hepatitis and the gap in HCV care cascades in this special population by a large-scale surveillance study in Taiwan. Uraemic patients on maintenance haemodialysis from 22 sites (FORMOSA-LIKE group) in 2012 (n = 1,680) and 2019 (n = 2,326) were recruited for this study. The distributions and sequential changes of viral hepatitis markers were analysed. The prevalence of anti-HCV antibody and hepatitis B surface antigen (HBsAg) seropositivity was 13.6% (316/2326) and 11.5% (267/2326), respectively, in 2019 compared with 17.3% (290/1680, P = .002) and 13.6% (229/1680, P = .046), respectively, in 2012. The HCV-viremic rate among anti-HCV-seropositive patients was significantly lower in 2019 than in 2012 (56.3% [178/316] vs. 73.8% [214/290], P < .001). The HCV treatment rate increased from 2.3% (5/217) in 2012 to 21.7% (49/226) in 2019 (P < .001). In the sequential analysis of the 490 patients who participated in both screens, 17 of the 55 HCV-viremic patients became HCV RNA seronegative, including 13 by antivirals and four spontaneously. By contrast, one anti-HCV-seropositive but nonviremic patient became viremic, and six anti-HCV-seronegative patients became anti-HCV-seropositive in 2019. The annual incidence of new HCV was 0.2%/year. Seven HBsAg-seropositive patients experienced HBsAg loss (1.25%/year). Two patients had new anti-HBc seropositivity (new HBV exposure: 0.57%/year). The seroprevalence of viral hepatitis decreased in an 8-year follow-up but remained prevalent, and the treatment of HCV infection was underutilized in uraemic patients. Additional efforts are needed to enhance the HCV treatment uptake of uraemic patients. Clinical Trial IDs: NCT03803410, NCT01766895.

HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified.

AIM

We evaluated the impact of infection with HBV on the risk of CKD in the general population.

MATERIAL AND METHODS

We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed.

RESULTS

We retrieved 33 studies (n=7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n=1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P<.001). Between-study heterogeneity was noted (Q value, 49.5, P<.0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n=3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P=.5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P<.015).

CONCLUSIONS

It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Association Between Hepatitis C Virus and Chronic Kidney Disease: A Systematic Review and Meta-Analysis

INTRODUCTION AND AIM

The role of hepatitis C virus infection as a risk factor for the development and progression of chronic kidney disease in the general population remains unclear.

MATERIAL AND METHODS

A systematic review of the published medical literature was performed to assess whether positive anti-HCV serologic status is associated with higher frequency of chronic kidney disease in the adult general population. We used a random-effects model to generate a summary estimate of the relative risk of chronic kidney disease (defined by lowered glomerular filtration rate or detectable proteinuria) with HCV across the published studies. Meta-regression and stratified analysis were also carried out.

RESULTS

Forty studies were eligible (n = 4,072,867 patients), and separate meta-analyses were conducted according to the outcome. Pooling results of longitudinal studies (n = 15 studies, n = 2,299,134 unique patients) demonstrated an association between positive anti-HCV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HCV across the surveys, 1.54 (95% CI, 1.26; 1.87) (P &lt; 0.001). Between-study heterogeneity was observed (Q value by Chi-squared [χ2] test 500.3, P &lt; 0.0001). The risk of chronic kidney disease related to HCV, in the subset of surveys from Asia was 1.45 (1.27; 1.65) (P &lt; 0.001) (no heterogeneity). According to our meta-regression, ageing (P &lt; 0.0001) and duration of follow-up (P &lt; 0.0001) increased the risk of chronic kidney disease among HCV-positive subjects. We observed a relationship between anti-HCV positive serologic status and frequency of proteinuria, adjusted effect estimate of proteinuria with HCV among surveys was 1.633 (95% CI, 1,29; 2.05) (P &lt; 0.001) (n = 10 studies; 315,404 unique patients). However, between-studies heterogeneity was noted (P value by Q test &lt; 0.0001).

CONCLUSION

An association between HCV infection and increased risk of chronic kidney disease in the general population exists. The mechanisms underlying such association are currently under active investigation.

Association between hepatitis B virus infection and chronic kidney disease: A cross-sectional study from 3 million population aged 20 to 49 years in rural China

Hepatitis B virus (HBV) infection can lead to different types of chronic kidney diseases (CKD) in clinical practice. However, HBV infection has been observed to have no significant association with CKD indicators in some epidemiological surveys. This research aims to estimate CKD prevalence in HBV infection population and clarify the relationship between HBV infection status and CKD.The participants aged 20 to 49 years were selected by multistage random sampling from January 1, 2010 to December 31, 2012 across 31 provinces and regions in rural China. The data was collected by standard questionnaire and physical check-up. Status of HBV infection was diagnosed as immune tolerant phase, hepatitis B envelope antigen -positive chronic HBV infection, inactive HBV carrier, hepatitis B envelope antigen -negative chronic HBV infection and resolved HBV infection based on serological markers, and the level of hepatic function, respectively.In total, 2,969,502 subjects were included in the study. In population aged 20 to 49 years in rural China, prevalence of HBV infection was 12.17%. Prevalence of proteinuria, hematuria, estimated glomerular filtration rate less than 60 mL/min/1.73m and CKD was 0.94%(95% CI = 0.91-0.97%) vs. 0.65%(95% CI = 0.64-0.66%), 1.92%(95% CI = 1.87-1.96%) vs. 1.19% (95% CI = 1.18-1.21%), 1.02%(95% CI = 0.99-1.06%) vs. 0.77% (95% CI = 0.76-0.78%), and 3.85%(95% CI = 3.78-3.91%) vs. 2.60%(95% CI = 2.58-2.62%) in population with HBV infection and without infection, respectively. Prevalence of CKD and indicators was higher in population in every status of HBV infection than in population without infection, respectively (all P < 0·0001). Every HBV infection status was a risk factor for CKD.CKD prevalence was higher in population in every status of HBV infection than without infection. HBV infection was a risk factor for CKD in population aged 20 to 49 years in rural China.

Considering hepatitis C virus infection as a systemic disease

Hepatitis C virus (HCV) infection has been demonstrated to result in several adverse hepatic outcomes and has been associated with a number of important extrahepatic manifestations. The scope of extrahepatic clinical possibilities includes systemic diseases such as vasculitis and lymphoproliferative disorders, cardiovascular disease, myalgia, arthritis, and sicca syndrome. These end-organ effects of HCV may dominate the clinical course beyond the hepatic complications and significantly worsen the long-term prognosis of infected patients. Until several years ago, the standard of care for the treatment of HCV infection had been interferon-alpha-based regimens, which not only had limited effectiveness in achieving a cure but were often poorly tolerated, especially in patients with kidney disease. In those HCV-infected patients with significant systemic manifestations, the interferon-based regimens were problematic given their association with a wide variety of toxicities. The development of highly effective direct-acting antiviral agents to treat HCV infection presented an opportunity to improve the HCV care cascade with the eradication of HCV in most infected patients and by reducing the burden of both hepatic and extrahepatic complications.

Hepatitis B virus infection and development of chronic kidney disease: a cohort study

Background

The effect of chronic hepatitis B virus (HBV) infection on the risk of chronic kidney disease (CKD) is controversial. We examined the prospective association between hepatitis B surface antigen (HBsAg) serology status and incident CKD in a large cohort of men and women.

Methods

Cohort study of 299,913 adults free of CKD at baseline who underwent health screening exams between January 2002 and December 2016 in South Korea. Incident CKD was defined as the development of an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m² and/or proteinuria.

Results

Over 1,673,701 person-years of follow-up, we observed 13,924 incident cases of CKD (3225 cases of eGFR < 60 ml/min/1.73m² and 11,072 cases of proteinuria). In fully adjusted models comparing positive to negative HBsAg participants, the hazard ratio (HR, 95% confidence interval) for incident CKD was 1.11 (1.03–1.21; P = 0.01). The corresponding HR for incident proteinuria and for eGFR < 60 ml/min/1.73m² were 1.23 (1.12–1.35; P <  0.001) and 0.89 (0.73–1.07; P = 0.21), respectively. The associations were similar across categories of liver enzyme levels at baseline.

Conclusion

In this large cohort, HBsAg positive serology was associated with higher risk of incident CKD, and we provide novel evidence that this association was due to a higher incidence of proteinuria in HBsAg positive participants. Our study adds to the growing body of evidence suggesting that chronic HBV infection may be a contributor to the increasing incidence of CKD.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1154-4) contains supplementary material, which is available to authorized users.

The association of hepatitis C infection with the onset of CKD and progression into ESRD

Hepatitis C virus (HCV) infection is not only an important cause of chronic liver disease, but extrahepatic manifestations are common and include chronic kidney disease (CKD). HCV is classically associated with cryoglobulinemic glomerulonephritis in the context of mixed cryoglobulinemia syndrome, but other glomerular diseases also occur and may be significantly under-recognized. HCV may cause glomerular disease by immune complex deposition; however, other potential mechanisms by which HCV promotes CKD include a direct cytopathic effect of the virus on renal tissue, and by its association with accelerated atherosclerosis, insulin resistance, and chronic inflammation. Epidemiologic studies show HCV infection confers an increased risk of incident CKD and accelerates progression of CKD to end-stage renal disease (ESRD) in the general population, as well as subpopulations including diabetic patients, those coinfected with human immunodeficiency virus (HIV), and kidney transplant recipients. Patients with CKD and HCV infection experience inferior clinical outcomes, including poorer quality of life and an increased risk of mortality. Treatment with interferon-based regimens is associated with decreased risk of incident CKD and ESRD, though prior studies are limited by the small number of patients with HCV and CKD who underwent treatment. With the advent of new, well-tolerated direct-acting antiviral combinations that are not cleared by the kidneys, it is possible to treat all genotypes of HCV infection in patients with CKD and ESRD. More data on the effect of direct-acting antivirals on CKD incidence and progression are necessary. However, there is every expectation that with improved access to HCV treatment, the burden of CKD in patients with HCV could significantly decline.

Hepatitis C and renal transplantation in era of new antiviral agents

Data from World Health Organization estimates that the hepatitis C virus (HCV) prevalence is 3% and approximately 71 million persons are infected worldwide. HCV infection is particularly frequent among patients affected by renal diseases and among those in dialysis treatment. In addition to produce a higher rate of any cause of death, HCV in renal patients and in renal transplanted patients produce a deterioration of liver disease and is a recognized cause of transplant glomerulopathy, new onset diabetes mellitus and lymphoproliferative disorders. Treatment of HCV infection with interferon alpha and/or ribavirin had a poor efficacy. The treatment was toxic, expensive and with limited efficacy. In the post-transplant period was also cause of severe humoral rejection. In this review we have highlighted the new direct antiviral agents that have revolutionized the treatment of HCV both in the general population and in the renal patients. Patients on dialysis or with low glomerular filtration rate were particularly resistant to the old therapies, while the direct antiviral agents allowed achieving a sustained viral response in 90%-100% of patients with a short period of treatment. This fact to date allows HCV patients to enter the waiting list for transplantation easier than before. These new agents may be also used in renal transplant patients HCV-positive without relevant clinical risks and achieving a sustained viral response in almost all patients. New drug appears in the pipeline with increased profile of efficacy and safety. These drugs are now the object of several phases II, III clinical trials.

Treatment of early stage chronic hepatitis C virus infection

INTRODUCTION

Treatment of Hepatitis C Virus (HCV) with direct acting antivirals (DAAs) is able to achieve the cure of infection in almost the totality of patients, independently of the characteristics of the individual and the virus, using short treatment schedules, and without the need of ribavirin. The high cost of DAAs is the main limiting factor for universal treatment of HCV. However, there is a strong evidence that treatment of infection at the early stage of disease may be the most rewarding approach. Areas covered: This review evaluates the aspects underlying the benefit of treating chronic HCV infection at the early stage of disease. It outlines the considerations that have to be taken into account when planning treatment in patients with HCV and minimal liver disease, assessing the positive reflex of viral eradication on several HCV-associated extra-hepatic conditions such as the risk of lymphoma, insulin-resistance and glycaemic control, and renal function. Lastly, it also covers the improvement of patients' quality of life and the pharmaco-economic aspects associated with early treatment. Expert commentary: Treatment of patients with HCV and minimal liver disease is associated with a beneficial, pleiotropic effect of viral eradication that goes beyond the simplistic consideration of the improvement in liver disease-related outcomes.

A systematic review and meta-analysis: Does hepatitis C virus infection predispose to the development of chronic kidney disease?

We aimed to meta-analytically assess the predisposition of hepatitis C virus (HCV) infection to the occurrence and severity of chronic kidney disease (CKD). Two authors independently searched articles and abstracted information. Odds ratio (OR) or hazard ratio (HR) along with 95% confidence interval (CI) was converged separately in 12 longitudinal (1,972,044 subjects) and 15 cross-sectional (937,607 subjects) studies. Overall effect estimate was remarkably significant in longitudinal studies (HR, 95% CI, P: 1.45, 1.23-1.71, < 0.001), in contrast to that in cross-sectional studies (OR, 95% CI, P: 1.25, 0.90-1.73, 0.188), with obvious heterogeneity (I² > 95%). HCV infection was also associated with an 1.54-fold (95% CI, P: 1.27-1.87, < 0.001) increased risk of having prevalent proteinuria. In longitudinal studies with estimated glomerular filtration rate (eGFR) < 60, < 30 and < 15 ml/min/1.73m², the corresponding HR was 1.39 (95% CI, P: 1.14-1.69, 0.001), 1.79 (0.91-3.51, 0.091) and 2.30 (1.26-4.19, 0.007). Further grouping the longitudinal studies by median follow-up time at 5 years revealed that the effect estimate was reinforced in long-term studies (HR, 95% CI, P: 1.86, 1.19-2.89, 0.006; I²=98.1%) relative to that in short-term studies (1.21, 1.03-1.43, 0.024; 92.0%). In conclusion, our findings demonstrate the significant risk of experiencing incident CKD after HCV infection, with the lower eGFR and longer HCV exposure time entailing a greater risk.

Hepatitis C and Its Metabolic Complications in Kidney Disease

INTRODUCTION

Evidence has been accumulated during the last decade showing that HCV infection plays an important activity at hepatic and extra-hepatic level. Chronic HCV is associated with a large spectrum of extra-hepatic manifestations including lympho-proliferative diseases and metabolic abnormalities (such as insulin resistance and fatty liver disease).

MATERIAL AND METHODS

We have performed an extensive review of the medical literature regarding the increased risk of cardiovascular and kidney disease that has been observed in various groups of HCV-infected patients. The potential link between such increased risk and the metabolic consequences of chronic HCV infection has been explored.

RESULTS

According to a systematic review with a meta-analysis of longitudinal studies (n = 9 clinical observational studies; n = 1,947,034 unique patients), we found a strong relationship between positive anti-HCV serologic status and increased incidence of chronic kidney disease in the adult general population, the summary estimate for adjusted hazard ratio was 1.43 (95% confidence intervals, 1.23; 1.63, P = 0.0001) (random-effects model) in anti-HCV positive patients. In another meta-analysis of clinical observational studies (n = 145,608 unique patients on long term dialysis; n = 14 observational studies), anti-HCV sero-positive status was an independent and significant risk factor for death in patients on maintenance dialysis. The summary estimate for adjusted relative risk (all-cause mortality) was 1.35 with a 95% confidence interval (CI) of 1.25; 1.47 (P &lt; 0.01) in anti-HCV positive patients on maintenance dialysis. An updated and stratified analysis (n = 4 studies, n = 91,916 patients on maintenance dialysis) resulted in an adjusted HR for cardiovascular mortality among anti-HCV positive patients of 1.21 (95% CI, 1.06; 1.39) (P &lt; 0.01); the homogeneity assumption was not rejected. The mechanisms underlying such relationships remain unclear; it has been suggested that HCV promotes atherogenesis through direct and indirect mechanisms.

CONCLUSIONS

Clinical trials are under way to assess whether the clearance of HCV RNA from serum by direct-acting antiviral drugs reduces all cause or disease-specific (cardiovascular) mortality among patients on maintenance dialysis.

Arterial stiffness evaluated by carotid-femoral pulse wave velocity increases the risk of chronic kidney disease in a Chinese population-based cohort

AIM

Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease. Although pulse wave velocity (PWV), which reflects arterial stiffness, was increased in subjects with CKD, little is known regarding whether arterial stiffness can increase the risk of CKD. To help clarify this we conducted a prospective cohort study to measure the association of arterial stiffness with CKD.

METHODS

A total of 7154 adults aged 54.8 ± 10.6 years undergoing physical examinations without CKD at baseline were enrolled. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cfPWV). CKD was defined as decreased estimated glomerular filtration rate (eGFR < 60 mL/min per 1.73 m² ) or presence of proteinuria (urine protein ≥ 1+) assessed using a repeated dipstick method.

RESULTS

During 3 years of follow-up, 167 (2.3%) patients developed CKD, 101 (1.4%) patients with proteinuria and 68 (1.0%) patients with decreased eGFR. After adjusted for potential confounders, either cfPWV (per 1 m/s increase) or the highest quartile of cfPWV (increased cfPWV) was independently associated with increased risk of proteinuria, with a fully adjusted OR of 1.15 (95% CI, 1.07 to 1.23) and 1.93 (95% CI, 1.15 to 3.25), respectively. By contrast, neither cfPWV (per 1 m/s increase) nor increased cfPWV was associated with decreased eGFR in the multivariable logistic regression analysis.

CONCLUSIONS

The study revealed that arterial stiffness increases the risk of proteinuria. This suggests that vascular stiffness could be considered as a target for delaying the development of CKD.

Association of H. pylori infection with chronic kidney disease among Chinese adults

BACKGROUND

Some studies have suggested that Helicobacter pylori (H. Pylori) infection was associated with insulin resistance and metabolic syndrome, which may increase the risk of chronic kidney disease (CKD). But there is no conclusive evidence regarding the association between H. Pylori infection and CKD. To help clarify this, we conducted the cross-sectional study to investigate the association of H. pylori infection with CKD among Chinese adults.

METHODS

A total of 22,044 adults aged 48.6 ± 14.3 years were enrolled. H. pylori-specific immunoglobulin G antibody titers were measured by ELISA. CKD was defined as estimated glomerular filtration rate (eGFR) less than <60 ml/min/1.73 m² or presence of proteinuria (urine protein ≥ 1+) assessed using a repeated dipstick method.

RESULTS

Among all participants in this study, the prevalence of H. Pylori infection was 20.6%. As a categorical outcome, the prevalence of decreased eGFR in the H. Pylori infection group was higher than in the non-H. Pylori infection group (1.6 vs. 1.2%, P = 0.04), but the prevalence of proteinuria and the overall CKD were not significantly different between these two groups (1.7 vs. 1.6%, P = 0.65 and 3.0 vs. 2.7%, P = 0.2). After adjusted for age, sex, hypertension, diabetes, body mass index, uric acid, smoking, drinking, total cholesterol, triglycerides, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, the odds of decreased eGFR and proteinuria were not significantly different between the H. Pylori positive and negative subjects.

CONCLUSIONS

This study did not find an association between H. Pylori infection and CKD.

Association between hepatitis B virus and chronic kidney disease: a systematic review and meta-analysis

 Background. Hepatitis B virus infection and chronic kidney disease are prevalent and remain a major public health problem worldwide. It remains unclear how infection with hepatitis B virus impacts on the development and progression of chronic kidney disease.

AIM

To evaluate the effect of infection with HBV on the risk of chronic kidney disease in the general population.

MATERIAL AND METHODS

We conducted a systematic review of the published medical literature to determine if hepatitis B infection is associated with increased likelihood of chronic kidney disease. We used the random effects model of DerSimonian and Laird to generate a summary estimate of the relative risk for chronic kidney disease (defined by reduced glomerular filtration rate and/or detectable proteinuria) with hepatitis B virus across the published studies. Meta-regression and stratified analysis were also conducted.

RESULTS

We identified 16 studies (n = 394,664 patients) and separate meta-analyses were performed according to the outcome. The subset of longitudinal studies addressing ESRD (n = 2; n = 91,656) gave a pooled aHR 3.87 (95% CI, 1.48; 6.25, P < 0.0001) among HBV-infected patients and no heterogeneity was recorded. In meta-regression, we noted the impact of male (P = 0.006) and duration of follow- up (P = 0.007) upon the adjusted hazard ratio of incidence of chronic kidney disease (including end-stage renal disease). No relationship occurred between HBV positive status and prevalent chronic disease (n = 7, n = 109,889 unique patients); adjusted odds ratio, were 1.07 (95% CI, 0.89; 1.25) and 0.93 (95% CI, 0.76; 1.10), respectively.

CONCLUSIONS

HBV infection is possibly associated with a risk of developing reduced glomerular filtration rate in the general population; no link between HBV sero-positive status and frequency of chronic kidney disease or proteinuria was noted in cross-sectional surveys.

Hyperhomocysteinemia increases the risk of chronic kidney disease in a Chinese middle-aged and elderly population-based cohort

BACKGROUND

Patients either with hyperhomocysteinemia or chronic kidney disease (CKD) have an increased risk of cardiovascular disease. Little is known regarding whether hyperhomocysteinemia can increase the risk of CKD in a Chinese middle-aged and elderly population. To help clarify this we conducted a prospective cohort study to measure the association of hyperhomocysteinemia with CKD.

METHODS

A total of 5917 adults aged 56.4 ± 9.6 years without CKD at baseline were enrolled. The highest homocysteine quartile (≥15 μmol/L) was defined as hyperhomocysteinemia. CKD was defined as decreased estimated glomerular filtration rate (eGFR < 60 mL/min/1.73 m²) or presence of proteinuria (urine protein ≥ 1+) assessed using a repeated dipstick method.

RESULTS

During 3 years of follow-up, 143 (2.4%) patients developed CKD, 85 (1.4%) patients with proteinuria and 59 (1.0%) patients with decreased eGFR. After adjusted for potential confounders, both homocysteine (per 1 μmol/L increase) and hyperhomocysteinemia were independently associated with increased risk of decreased eGFR [with a fully adjusted OR of 1.07 (95% CI 1.04-1.10) and 3.05 (95% CI 1.71-5.46)] and CKD [with a fully adjusted OR of 1.04 (95% CI 1.02-1.07) and 1.62 (95% CI 1.11-2.35)], respectively. By contrast, neither homocysteine (per 1 μmol/L increase) nor hyperhomocysteinemia were associated with proteinuria in the multivariable logistic regression analysis.

CONCLUSIONS

The study revealed that hyperhomocysteinemia increases the risk of decreased eGFR. This suggests that homocysteine could be considered as a useful molecular markers for delaying the development of CKD.

Relationship between hepatitis B virus infection and chronic kidney disease in Asian populations: a meta-analysis

PURPOSE

To evaluate the association of Chronic hepatitis B virus (HBV) infection and chronic kidney disease (CKD).

METHODS

We searched Embase, Grateful Med, Ovid, PubMed, and the China Biological Medicine Database. A meta-analysis was performed to assess whether HBV infection plays an independent impact on the development of CKD in the general population. Relative risks of CKD (defined as reduced glomerular filtration rate or proteinuria) according to HBsAg serologic status were studied.

RESULTS

Six eligible clinical studies (189,709 individuals in total) were included in the analysis. There was no association between HBsAg seropositive status and prevalence of CKD, the summary estimate for adjusted relative risk (RR) was 1.16 (95% confidence interval (CI), 0.78, 1.71; p = .46) according to the random-effects model, and between studies heterogeneity was noted (p values by Q test <0.001). Also, there were no significant associations between positive HBV serologic status and low eGFR (adjusted relative risk, 0.95; 95% CI, 0.72, 1.26; p = .72) or proteinuria (adjusted relative risk, 1.00; 95% CI, 0.83, 1.20; p = .99).

CONCLUSIONS

This meta-analysis shows that there was no association between exposure to HBV and the risk of developing CKD in Asian populations.

New insights into HCV-related rheumatologic disorders: A review

Hepatitis C virus (HCV) infected patients are known to be exposed to major liver complications i.e. cirrhosis and hepatocellular carcinoma. In addition, many extrahepatic manifestations including rheumatologic disorders have been reported in up to two-third of HCV infected patients. These manifestations include frank auto-immune and rheumatic diseases (such as arthralgia, myalgia, arthritis, sicca syndrome and vasculitis) which may dominate the course of infection. Until recently, the standard of care of HCV has been the use of interferon-alpha based regimens, which not only had limited effectiveness in HCV cure but were poorly tolerated. In patients with rheumatic diseases interferon-based regimens may be problematic given their association with a wide variety of autoimmune toxicities. Recent therapeutic advances with new direct anti-HCV therapies (interferon-free) which are more effective and better tolerated, make screening for this comorbidity in patients with rheumatic disorders more important than ever. This review aimed to outline main HCV extrahepatic with a special focus on rheumatologic manifestations.

Does Nucleos(t)ide Analogues Treatment Affect Renal Function in Chronic Hepatitis B Patients Who Have Already Decreased eGFR? A Longitudinal Study

This study aimed to assess the renal function in chronic hepatitis B (CHB) patients who received nucleos(t)ide analogues (NAs) therapy using estimated glomerular filtration rate (eGFR) titer. We performed a longitudinal observational study of 37 tenofovir-, 42 telbivudine-, and 62 entecavir-naïve CHB patients, who had impaired renal function (eGFR, 90-30 ml/min/1.73m2) without history of diabetes, hypertension, and chemotherapy. Calculation and evaluation of eGFR was performed with the Modification of Diet in Renal Disease, Chronic Kidney Disease Epidemiology Collaboration, and Cockcroft-Gault formula at pretreatment, at baseline, and after the 1st and 2nd year of treatment. The eGFR was significantly increased in patients given telbivudine or entecavir (p = 0.003 and p = 0.012, respectively), but the eGFR was decreased in patients given tenofovir (p = 0.001) after 2 years of treatment. Of all patients, eGFR was stable one year prior to treatment. If we analyzed the renal function by change of chronic kidney disease (CKD) category with a change of 25% of eGFR, the proportion of uncertain drop (drop in CKD category with <25% decrease in eGFR) and certain drop (drop in CKD category with ≧25% decrease in eGFR) in tenofovir group was smaller (5.4%) than those of telbivudine (12.9%) or entecavir (6.5%). Furthermore, telbivudine had the lowest stable rate (76.2%), the highest certain rise rate (9.5%), and certain drop rate (7.1%) compared to the other groups (p = 0.049). In conclusion, in NAs-naïve CHB patients with impaired renal function, telbivudine and entecavir resulted in a significant increase in eGFR while tenofovir resulted in a significant decrease after a 2-year treatment. Interestingly, TDF had the lowest proportion of patients reclassified to certain and uncertain drop groups; in contrast, LdT had a higher proportion in both raise and drop groups. The outcomes of this renal effect remain to be determined.

Extrahepatic manifestations of chronic hepatitis C virus infection

During hepatitis C virus (HCV) chronic infection, extrahepatic manifestations are frequent and polymorphous. This article reports on a large cohort of patients with HCV-related autoimmune or lymphoproliferative disorders, from mixed cryoglobulinemia vasculitis to frank lymphomas. The relationship between HCV infection and such immune-related diseases has been formally demonstrated by epidemiological, clinical, immunological and pathological data, and results of therapeutic trials. More recently, other nonliver-related HCV disorders have been reported, including cardiovascular (i.e. stroke, ischemic heart disease), renal, metabolic and central nervous system diseases. For these manifestations, most evidence comes from large epidemiological studies; there is a need for mechanistic studies and therapeutic trials for confirmation. Beyond the risk of developing liver complications, that is, cirrhosis and liver cancer, patients with HCV infection have an increased risk of morbidity and mortality related to nonliver diseases. HCV chronic infection should be analyzed as a systemic disease in which extrahepatic consequences increase the weight of its pathological burden. The need for effective viral eradication measures is underlined.

Death Does Matter--Cancer Risk in Patients With End-Stage Renal Disease: A Nationwide Population-Based Study With Competing Risk Analyses

Patients with end-stage renal disease (ESRD) have a high mortality rate. We hypothesized that not accounting for death as a competing risk overestimates the event rate caused by ESRD. Thus, we examined the cancer risk for patients with ESRD (ESRD) after death as a competing risk event had been adjusted for. Patients with newly diagnosed ESRD (n = 64,299) between 1999 and 2007, together with age- and sex-matched controls without ESRD (ESRD) (n = 128,592) were enrolled (1:2). In a Cox proportional hazards model that included death as a competing risk, ESRD patients in Taiwan had a lower overall incidence (subdistribution hazard ratio [sdHR] = 1.29) of cancer than did ESRD patients in a Cox model that did not include death as a competing risk (HR = 1.70). After competing mortality had been adjusted for, ESRD patients ≥70 (sdHR = 0.82) and ESRD patients on long-term dialysis (> 5 follow-up years, sdHR = 0.62), had a lower risk for developing cancer than did ESRD patients. This finding supported our hypothesis that standard survival analyses overestimate the event rate, especially when the mortality rate is high. It also showed that ESRD patients, when they grow older, were far less likely to develop cancer and far more likely to die because of underlying illnesses that might also affect the risk of death because of ESRD.

Hepatitis C Virus Infection Increases the Risk of Developing Chronic Kidney Disease: A Systematic Review and Meta-Analysis

BACKGROUND AND RATIONALE

Chronic kidney disease and hepatitis C virus are prevalent in the general population worldwide, and controversy exists about the impact of HCV infection on the development and progression of kidney disease.

DESIGN

A systematic review of the published medical literature was made to assess whether positive anti-HCV serologic status plays an independent impact on the development of chronic kidney disease in the adult general population. We used a random-effects model to generate a summary estimate of the relative risk of chronic kidney disease (defined by reduced glomerular filtration rate or detectable proteinuria) with HCV across the published studies. Meta-regression and stratified analysis were also conducted.

RESULTS

Twenty-three studies (n = 2,842,421 patients) were eligible, and separate meta-analyses were performed according to the outcome. Pooling results of longitudinal studies (n = 9; 1,947,034 unique patients) demonstrated a relationship between positive HCV serologic status and increased incidence of chronic kidney disease, the summary estimate for adjusted hazard ratio was 1.43 (95% confidence interval 1.23; 1.63, P = 0.0001), and between-studies heterogeneity was noted (P value by Q test <0.0001). The risk of the incidence of chronic kidney disease associated with HCV, in the subset of Asian surveys, was 1.31 (95% confidence interval 1.16; 1.45) without heterogeneity (P value by Q test = 0.6). HCV positive serology was an independent risk factor for proteinuria; adjusted odds ratio, 1.508 (95% confidence intervals 1.19; 1.89, P = 0.0001) (n = 6 studies; 107,356 unique patients).

CONCLUSIONS

HCV infection is associated with an increased risk of developing chronic kidney disease in the adult general population.

Hepatitis B virus-related glomerulonephritis: not a predominant cause of proteinuria in korean patients with chronic hepatitis B

Background/Aims. Hepatitis B virus (HBV) can form immune complexes which may result in various types of glomerulonephritis (GN). However, proteinuria can occur because of other kidney diseases besides HBV-related GN (HBV-GN). The aim of this study is to elucidate the causes of proteinuria and report on the clinical outcomes of HBV-GN. Methods. We reviewed the medical records of patients positive for serum hepatitis B surface antigen who underwent renal biopsies due to proteinuria at a tertiary medical center in Korea. Results. A total of 55 patients were included. HBV-GN was diagnosed in 20 (36.4%) of the patients by confirming the presence of immune complexes (12 of 13 membranoproliferative glomerulonephritis, 7 of 8 membranous glomerulonephritis, and 1 of 13 immunoglobulin A nephropathy). Twenty-one patients had other types of GN. A total of 13 (65%) HBV-GN patients were treated with antiviral agents for a median of 11 months. However, the degrees of proteinuria were not significantly reduced in the antiviral intervention group when compared to the control group. Conclusions. Proteinuria can be caused by various glomerular diseases and HBV-GN accounts for one-third of total GN cases. Well-designed prospective study is needed to assess whether antiviral therapy against HBV infection may improve the prognosis of HBV-GN.

Hepatitis B Virus Infection and the Kidney: Renal Abnormalities in HBV Patients, Antiviral Drugs Handling, and Specific Follow-Up

Chronic hepatitis B virus (CHB) infection is one of the most common causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. Many patients with CHB have variable degrees of functional renal impairment, and approximately 2 to 15% of patients on hemodialysis have CHB. Several therapeutic regimens have been developed in the past years, among which oral nucleoside and nucleotide analogues have been demonstrated to be efficient and well tolerated. However, they all are excreted in the urine and may thus require dosage adjustment in patients with decreased renal function. Furthermore, a number of them may in addition be toxic to the kidneys, especially in those patients presenting with renal insufficiency.

Management of patients with hepatitis C infection and renal disease

Hepatitis C virus (HCV) infection in patients with end-stage renal disease (ESRD) is associated with more rapid liver disease progression and reduced renal graft and patients' survival following kidney transplantation. Evaluations and management of HCV in patients with renal disease are challenging. The pharmacokinetics of interferons (IFN), ribavirin (RBV) and some direct acting antiviral (DAA), such as sofosbuvir, are altered in patients with ESRD. With dose adjustment and careful monitoring, treatment of HCV in patients with ESRD can be associated with sustained virological response (SVR) rates nearly comparable to that of patients with normal renal function. DAA-based regimens, especially the IFN-free and RBV-free regimens, are theoretically preferred for patients with ESRD and KT in order to increase SVR rates and to reduce treatment side effects. However, based on the data for pharmacokinetics, dosing safety and efficacy of DAA for patients with severe renal impairment are lacking. This review will be focused on the evaluations, available pharmacologic data, and management of HCV in patients with severe renal impairment, patients who underwent KT, and those who suffered from HCV-related renal disease, according to the available treatment options, including DAA.

Prevalence of renal abnormalities in chronic HBV infection: the HARPE study

BACKGROUND & AIMS

Few data are available on the prevalence of renal abnormalities in chronic hepatitis B virus (HBV)-infected patients. The multicentric cross-sectional HARPE study evaluated the prevalence of kidney disease indicators, in chronic HBV surface antigen carriers patients (HBsAg+) with active or inactive infection.

PATIENTS AND METHODS

Two hundred and sixty-eight HBsAg+ adult patients, naïve of any oral antihepatitis B virus treatment were prospectively included over 2 years. Data for renal assessment were collected once from patient files. Univariate tests and multiple linear regressions were performed with the SAS software, version 8.02 (SAS, Inc., Cary, NC, USA).

RESULTS

Among the 260 patients analysed, 58% were men, the mean age was 42 ± 14 years, 59.6% were inactive carriers whereas 47 patients, mostly active, were about to start an antiviral therapy. Prevalence of proteinuria, haematuria, glycosuria, uninfectious leukocyturia was 38.1%, 20.6%, 3.9% and 9% respectively. According to the international definition, a total of 64.6% of patients were found to have kidney disease. Diabetes, hypertension and dyslipidaemia were observed, respectively, in 4.6%, 9.2% and 38.8% patients. There were no significant differences in these results within the three subgroups.

CONCLUSION

Renal abnormalities are highly prevalent in our population and pre-exist before the initiation of any antihepatitis B virus treatment. This emphasizes the need for: (i) a baseline renal evaluation in all HBs antigen-positive patients; (ii) a regular renal monitoring before and during antihepatitis B virus treatment to diagnose and manage renal impairment and adjust antihepatitis B virus treatment doses to renal function when necessary.

HBsAg seroprevalence among Senegalese militaries

BACKGROUND

Chronic hepatitis is a major public health problem. Hepatitis B virus is the primary cause, and Hepatitis B and C together are responsible for 60% of cirrhosis and 80% of hepatocellular carcinomas. This study measured the prevalence of HBsAg among Senegalese military to develop an appropriate strategy to prevent cirrhosis and hepatocellular carcinoma.

METHODS

We conducted a descriptive cross-sectional study among Senegalese military aged 25 to 60 years. A sample of 1224 participants was selected following a two-level-stratification. The mark of surface HBs antigen using chemiluminescence concerned 1195 participants. The presence of HBsAg was analyzed according to age, marital status, alcohol consumption and glomerular filtration rate. Epi-info6fr and R software were used, respectively, for data capture and analyses. A Chi-square test was performed to compare proportions considering a significance level of 5% and a confidence interval of 95%.

RESULTS

The average age was 39.8 ± 9.2 years. Participants in the age groups of 25-34 years, 45-60 years and 35-44 years were respectively 30.7%, 34.4% and 34.9% of the sample. Married persons represented 82.6% of participants and 17.08% were single. Most participants were educated (99%), and 56% had reached at least secondary school level. Alcohol consumption was at 11.5%. The HBsAg prevalence rate was 10.8% [9.1% to 12.7%] with a significant difference between age groups (P < 0.001), which ranged from 5.6% for 45-60 years, 9.62% for 25-34 years to 16.9% for 35-44 years. Marital status and alcohol consumption did not affect the carriage of HBsAg. HBsAg prevalence was more common among participants who had a glomerular filtration rate greater than 90 ml/min. Transaminases rate exceeded the normal threshold for 43 participants (3.6%); the increase was 6.6% [2.7% to 11.8%] for HBsAg carriers and 3.2% [1.2% to 6.7%] for alcohol users.

CONCLUSIONS

The high prevalence of HBsAg in the military requires the implementation of an effective prevention and care program to reduce the risk of cirrhosis and hepatocellular carcinoma and contribute to reducing the burden of communicable diseases, such as hepatitis and HIV/AIDS, and non-communicable diseases.

Extrahepatic manifestations of chronic hepatitis C virus infection

Hepatitis C virus (HCV) infected patients are known to be at risk of developing liver complications i.e. cirrhosis and liver cancer. However, the risks of morbidity and mortality are underestimated because they do not take into account non-liver consequences of chronic hepatitis C virus infection. Numerous extrahepatic manifestations have been reported in up to 74% of patients, from perceived to disabling conditions. The majority of data concern hepatitis C virus-related autoimmune and/or lymphoproliferative disorders, from mixed cryoglobulinaemia vasculitis to frank lymphomas. More recently, other hepatitis C virus-associated disorders have been reported including cardiovascular, renal, metabolic, and central nervous system diseases. This review aims to outline most of the extrahepatic manifestations that are currently being investigated, including some of autoimmune and/or lymphoproliferative nature, and others in which the role of immune mechanisms appears less clear. Beyond the liver, hepatitis C virus chronic infection should be analyzed as a multifaceted systemic disease leading to heavy direct and indirect costs. The accurate consideration of extrahepatic consequences of such a systemic infection significantly increases the weight of its pathological burden. The need for effective viral eradication measures is underlined.

Bidirectional association between the risk of comorbidities and the diagnosis of retinal vein occlusion in an elderly population: a nationwide population-based study

BACKGROUND

Retinal vein occlusion (RVO) is the second most common retinal vascular disease, with peak incidence at 70years of age. However, the bidirectional association between the risk of comorbidities and the diagnosis of RVO in this population is uncertain.

METHODS

A population-based cohort of 1,784,960 patients 70years of age and older retrieved from the Taiwan National Health Insurance Research Database between 2000 and 2010. Risks of comorbidities were assessed 5years before and after the diagnosis of RVO.

RESULTS

In our study, 3393 subjects had central RVO (CRVO) and 6688 subjects had branch RVO (BRVO). Before the diagnosis of RVO, patients showed increased risks for the following comorbidities: hypertension (odds ratio [OR]=1.83, 95% confidence interval [CI], 1.74-1.93), dyslipidemia (OR=1.29, [1.23-1.35]), DM (OR=1.29, [1.23-1.35]), liver disease (OR=1.22, [1.16-1.29]), renal disease (OR=1.30, [1.23-1.37]), and cerebrovascular disease (OR=1.16, [1.11-1.21]). After the diagnosis of RVO, patients were at greater risk of developing DM (adjusted hazard ratio [AHR]=1.12, [1.06-1.19]), PAD (AHR=1.17, [1.08-1.27]), and MACE (AHR=1.35, [1.25-1.46]); however, the risk of all-cause mortality was unchanged. Elderly patients with CRVO had a significantly higher risk of all-cause mortality (AHR=1.09, [1.02-1.17]), whereas patients with BRVO showed no significant differences in mortality.

CONCLUSION

This study suggests bidirectional association between the risk of comorbidities and the diagnosis of RVO in an elderly population.

Age and gender differences in the relationship between hepatitis C infection and all stages of Chronic kidney disease

Chronic kidney disease (CKD) is a worldwide health issue with heavy economic burden. Chronic hepatitis C virus (HCV) infection is a common cause of CKD, which can significantly impact the progression and mortality among patients with CKD. The prevalence of both illnesses is high in Taiwan. A multicentre and population-based cross-sectional study including 24 642 subjects was conducted to explore the association of HCV infection with the prevalence and severity of CKD. The measurements of metabolic parameters, eGFR and CKD stages were compared between subjects with HCV seropositivity and seronegativity. The analyses of association between HCV infection with CKD stages and evaluation of potential risk factors of CKD were performed by gender and age (≤ and >45 years). HCV-seropositive subjects accounted for 6.9% and had a significantly older age. The prevalence of CKD increased in those with HCV seropositivity (16.5%). Significantly higher prevalence of CKD stages ≥3 in HCV-seropositive subjects was noticed (7.8%). Age (>45 year), male gender, alcohol drinking, hypertension, creatinine and HCV infection were the significant factors associated with the presence of CKD. HCV seropositivity was an independent risk factor of developing CKD and associated with an increased risk of having CKD of all stages. The higher prevalence of earlier stage of CKD warrants longitudinal studies with frequent testing on renal function and sufficient duration to determine the changes of eGFR over time. Implementation of effective treatment intervention is also required for these subjects to prevent the progression of CKD to late stages.

High hepatitis B virus surface antigen levels and favorable interleukin 28B genotype predict spontaneous hepatitis C virus clearance in uremic patients

BACKGROUND & AIMS

Host and viral factors interplay in the spontaneous clearance of hepatitis C virus (HCV) infection. We aimed to explore the roles of IL28B genotypes and hepatitis B virus (HBV) infections in spontaneous HCV seroclearance.

METHODS

IL28B rs8099917 genotypes, HCV and HBV markers were determined in 290 patients who were seropositive for HCV antibodies from 1681 total uremic patients on maintenance hemodialysis.

RESULTS

Persistent HCV viremia was observed in 74.6% (214/287) of patients. Logistic regression revealed that the strongest factors associated with spontaneous HCV seroclearance were carriage of rs8099917 TT-type (odds ratio/95% confidence intervals [OR/CI]: 6.22/1.41-27.35, p=0.016), followed by concurrent hepatitis B surface antigen (HBsAg) seropositivity (OR/CI: 2.37/1.06-5.26, p=0.035). The clearance rate was highest among patients with both positive HBsAg/rs8099917 TT-type (44.8%, OR/CI: 20.88/3.5-402.5), followed by positive HBsAg/rs8099917 non-TT-type (28.6%, OR/CI: 8.86/1.8-160.8), and negative HBsAg/rs8099917 TT-type (26.7%, OR/CI: 12.75/1.0-319.4), compared to 4% of negative HBsAg/rs8099917 non-TT-type (trend p=0.0002). HBsAg levels, but not HBV DNA levels, were significantly associated with spontaneous HCV seroclearance. Spontaneous HCV seroclearance rate was 58.3% in patients with HBsAg>200IU/ml/rs8099917 TT-type (OR/CI: 42.54/5.7-908.4), 28.0% in patients with HBsAg<200IU/ml/rs8099917 TT-type or HBsAg>200IU/ml/rs8099917 non-TT-type (OR/CI: 11.12/2.3-201.0), compared to only 3.3% in those with HBsAg<200IU/ml/rs8099917 non-TT-type (trend p=0.0004). Five of 214 (2.3%) HCV viremic patients at enrollment had spontaneous HCV seroclearance during one-year follow-up, which was associated with baseline HCV RNA and HBsAg levels.

CONCLUSIONS

High HBsAg levels and favorable IL28B genotype were additively associated with spontaneous HCV seroclearance in uremic patients.

Hepatitis C virus infection, mixed cryoglobulinemia, and kidney disease

Hepatitis C virus (HCV) may instigate mixed cryoglobulinemia; the most significant accompanying kidney lesion is type I membranoproliferative glomerulonephritis, usually occurring in the context of type II mixed cryoglobulinemia. Additionally, recent data support a link between HCV infection and proteinuria in population-based studies, raising the possibility that kidney diseases associated with HCV may be more common than previously thought. A number of strategies have been used to treat HCV-related glomerulonephritis, including antiviral agents, immunosuppressive therapies such as corticosteroids and cytotoxic agents, and plasma exchange. Limited but encouraging data about the utility of antiviral treatment in the setting of HCV-associated glomerulonephritis exist, with one pooled analysis noting a sustained viral response of 42%, albeit with significant heterogeneity. Immunosuppressive therapy may be most useful for cryoglobulinemic kidney disease, with individualized approaches considered for the treatment of HCV-associated cryoglobulinemic glomerulonephritis based on the level of proteinuria and kidney failure. Of note, rituximab, a chimeric monoclonal antibody that blocks CD20 receptors on B cells, has been reported to be effective for the treatment of mixed cryoglobulinemia symptoms, including glomerulonephritis.

Factors associated with CKD in the elderly and nonelderly population

BACKGROUND AND OBJECTIVES

The risk factors for CKD in different age groups remain unknown. This community-based study aimed to identify the risk factors for CKD in elderly and nonelderly patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A multistage sampling survey for CKD was conducted in 2007 in Kaohsiung County, an area with the highest prevalence of dialysis in the world. CKD was defined as proteinuria in at least the microalbuminuric stage or an estimated GFR (eGFR) of <60 ml/min per 1.73 m(2). The factors for CKD in elderly and nonelderly patient groups were identified (with age 60 years as a cutoff value).

RESULTS

The analyses included 3352 participants, of whom 687 had CKD. The weighted prevalence of CKD was 19.4% (95% confidence interval [CI], 18.0%-20.7%). Elderly patients typically presented with low eGFR and nonelderly patients, with proteinuria. Age, annual income, use of oral analgesics, metabolic syndrome, hyperuricemia, and hemoglobin were risk factors for CKD in both age groups. In elderly patients, risk factors were medical history of diabetes mellitus, CKD, stroke, and not using analgesic injection (odds ratios [95% CIs], 3.58 [2.06-6.22], 3.66 [1.58-8.43], 3.89 [1.09-13.87], 2.27 [1.21-4.17], respectively). In nonelderly patients, associated risk factors for CKD were gout, hepatitis B virus infection, and use of the Chinese herbal medicine Long Dan Xie Gan Tang (odds ratios [95% CIs], 3.15 [1.96-5.07], 1.66 [1.09-2.53], and 8.86 [1.73-45.45], respectively).

CONCLUSIONS

The risk factors for CKD vary by age.

Association of reduced renal function with hepatitis B virus infection and elevated alanine aminotransferase

BACKGROUND AND OBJECTIVES

Clinically, hepatitis B virus (HBV) infection is observed to be associated with nephropathy. However, previous population-based studies failed to show an association between HBV infection and CKD. Therefore, this cross-sectional study was designed to further explore this association.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A representative sample of 6854 Chinese adults aged 30-75 years was tested for levels of serum hepatitis B surface antigen, alanine aminotransferase (ALT), creatinine, urinary albumin/creatinine ratio, and potential CKD risk factors.

RESULTS

Neither HBV infection nor elevated ALT (ALT+; ≥ sex-specific 90th percentile of ALT levels of noninfected persons) was significantly associated with reduced estimated GFR (eGFR < 60 ml/min per 1.73 m(2)). Compared with noninfected persons, HBV-infected persons with ALT+, but not those with ALT- (P=0.26), were more likely to have reduced eGFR (odds ratio, 4.07; 95% confidence interval, 1.18-14.0; P=0.03). Further analysis with a general linear model revealed a significant difference in eGFR (mean ± SEM) between HBV-infected and noninfected persons (87.8±0.8 versus 90.2±0.4 ml/min per 1.73 m(2); P=0.002). This difference was mainly derived from that between HBV-infected persons with ALT+ and noninfected persons, with an average difference in eGFR of -4.5 (95% confidence interval, -0.9 to -8.1; P=0.01). HBV infection and ALT+, alone or in combination, were not significantly associated with albuminuria or CKD.

CONCLUSIONS

HBV infection with elevated ALT, rather than HBV infection alone, was associated with reduced renal function.

Hepatitis B and C co-infection are independent predictors of progressive kidney disease in HIV-positive, antiretroviral-treated adults

Chronic kidney disease (CKD) is an important cause of morbidity and mortality in HIV-positive individuals. Hepatitis C (HCV) co-infection has been associated with increased risk of CKD, but prior studies lack information on potential mechanisms. We evaluated the association between HCV or hepatitis B (HBV) co-infection and progressive CKD among 3,441 antiretroviral-treated clinical trial participants. Progressive CKD was defined as the composite of end-stage renal disease, renal death, or significant glomerular filtration rate (eGFR) decline (25% decline to eGFR <60 mL/min/1.73 m(2) or 25% decline with a baseline <60). Generalized Estimating Equations were used to model the odds of progressive CKD. At baseline, 13.8% and 3.3% of participants were co-infected with HCV and HBV, respectively. Median eGFR was 111, and 3.7% developed progressive CKD. After adjustment, the odds of progressive CKD were increased in participants with HCV (OR 1.72, 95% CI 1.07-2.76) or HBV (OR 2.26, 95% CI 1.15-4.44). Participants with undetectable or low HCV-RNA had similar odds of progressive CKD as HCV seronegative participants, while participants with HCV-RNA >800,000 IU/ml had increased odds (OR 3.07; 95% CI 1.60-5.90). Interleukin-6, hyaluronic acid, and the FIB-4 hepatic fibrosis index were higher among participants who developed progressive CKD, but were no longer associated with progressive CKD after adjustment. Future studies should validate the relationship between HCV viremia and CKD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00027352; NCT00004978.

High incidence of hepatocellular carcinoma in ESRD patients: caused by high hepatitis rate or 'uremia'? a population-based study

OBJECTIVE

A high incidence of hepatocellular carcinoma has been reported in end-stage renal disease patients. This study was undertaken to evaluate whether this was caused by a high rate hepatitis or 'uremia' per se.

METHODS

We used claims data of the Bureau of National Health Insurance of Taiwan for analysis. All patients diagnosed with end-stage renal disease having received their first dialysis between 1 January 2003 and 31 December 2007 (n = 38 714) were enrolled for the study. A database of 1 million randomly selected subjects matched for age, gender, hepatitis B and C infection, and liver cirrhosis for the same period was used as control (n = 38 714). The longest observation period was up to 31 December 2008.

RESULTS

There was no significant difference in the incidence of hepatocellular carcinoma between end-stage renal disease patients and their non-end-stage renal disease counterparts (2.03 per 1000 person-years vs. 2.10 per 1000 person-years, rate ratio = 0.947; 95% confidence interval: 0.792-1.132). End-stage renal disease patients with hepatocellular carcinoma had higher percentages of diabetes mellitus, hypertension, heart failure and gout (all P < 0.001), and they presented with a worse cumulative survival rate than the non-end-stage renal disease group (P < 0.001). End-stage renal disease patients developing hepatocellular carcinoma were younger, and had more comorbidities than their non-end-stage renal disease counterparts. End-stage renal disease (hazard ratio = 1.61) and diabetes mellitus (hazard ratio = 1.55) were found to be independent factors for mortality in hepatocellular carcinoma patients.

CONCLUSIONS

After matching for hepatitis and liver cirrhosis, end-stage renal disease is not associated with a higher incidence of hepatocellular carcinoma than the general population. The high incidence of hepatocellular carcinoma in end-stage renal disease patients was caused by a high viral hepatitis rate rather than 'uremia' per se. Owing to increased comorbidity, end-stage renal disease patients developing hepatocellular carcinoma had worse long-term survival than non-end-stage renal disease patients.

Hepatitis C virus, cryoglobulinemia, and kidney: novel evidence

Hepatitis C virus infection can lead to chronic active hepatitis, cirrhosis, and liver failure; however, it is also associated with a wide range of extra-hepatic complications. HCV is associated with a large spectrum of histopathological lesions in both native and transplanted kidneys, and it is increasingly recognized as an instigator of B cell lympho-proliferative disorders including mixed cryoglobulinemia. Mixed cyoglobulinemia is a systemic vasculitis primarily mediated by immune complexes; it is characterized by variable organ involvement including skin lesions, chronic hepatitis, glomerulonephritis, peripheral neuropathy, and arthralgias. The most frequent HCV-associated nephropathy is type I membranoproliferative glomerulonephritis, usually in the context of type II mixed cryoglobulinemia. Various approaches have been tried for the treatment of HCV-related glomerulonephritis, including immunosuppressive therapy (corticosteroids and cytotoxic agents), plasma exchange and antiviral agents. Data on the antiviral treatment of HCV-associated glomerulonephritis are not abundant but encouraging results have been provided. Immunosuppressive therapy is particularly recommended for cryoglobulinemic kidney disease. Recent evidence has been accumulated on rituximab therapy for HCV-related cryoglobulinemic glomerulonephritis exists but several questions related to its use remain unclear. Distinct approaches should be considered for the treatment of HCV-associated cryoglobulinemic glomerulonephritis according to the level of proteinuria and kidney failure.

The outcomes of glucose abnormalities in pre-diabetic chronic hepatitis C patients receiving peginterferon plus ribavirin therapy

BACKGROUND/AIMS

Pre-diabetes is a risk factor for type 2 diabetes mellitus (DM) development. This study aimed to elucidate the impact of treatment response on sequential changes in glucose abnormalities in pre-diabetic chronic hepatitis C (CHC) patients.

METHODS

Chronic Hepatitis C patients with a baseline haemoglobin A1C (A1C) range 5.7-6.4% who achieved 80/80/80 adherence were prospectively recruited. All patients received current peginterferon-based recommendations. The primary outcome measurement was their A1C level at the end of follow-up (EOF). The interaction between variants of the IL28B gene and outcomes of glucose metabolism was also measured.

RESULTS

A total of 181 consecutive CHC patients were enrolled. The mean A1C at EOF was 5.82 ± 0.41%, which was significantly lower than the baseline level (5.93 ± 0.21%, P < 0.001). At EOF, 63 (34.8%) patients became normoglycaemic, whereas 10 (5.5%) patients developed DM. The sustained virological response (SVR) rates of 63 normoglycaemics, 108 pre-diabetics and 10 diabetic patients at the EOF were 92.1%, 84.3% and 50% respectively (normoglycaemics vs. diabetics P = 0.003; pre-diabetics vs. diabetics P = 0.02). Achievement of an SVR was the only predictive factor associated with normoglycaemia development at EOF by multivariate logistic regression analysis (Odds ratio = 2.6, P = 0.04). The prevalence of the interleukin 28B rs8099917 TT variant in patients who developed DM (70.0%) at EOF tended to be lower than that in patients with pre-diabetics (87.0%) or normoglycaemics (92.1%).

CONCLUSION

Successful eradication of HCV improves glucose abnormalities in pre-diabetic CHC patients.

Thyroid autoantibodies and dysfunction do not impact the treatment efficacy of peginterferon and ribavirin combination therapy in chronic hepatitis C

AIMS

Thyroid disorders, such as the emergence of thyroid autoantibodies (TAs) and thyroid dysfunction (TD), are not uncommon in chronic hepatitis C (CHC) patients. The study aimed to investigate the impact of TAs and dysfunction on the treatment response to pegylated interferon-α plus ribavirin (PegIFN/RBV) combination therapy in CHC patients. The association between interleukin-28B (IL-28B) genetic variants and occurrence of TAs and dysfunction was also analyzed.

METHODS

A total of 449 treatment-naive Taiwanese CHC patients with euthyroid status were consecutively enrolled. They received PegIFN/RBV combination therapy with current recommendation. TAs, TD, and IL-28B genetic variants were measured before treatment. Monitoring of TD was done at 3-month intervals during treatment, at end of treatment, and at end of follow-up (EOF).

RESULTS

The development of TAs was detected in 42 (9.4%) patients before treatment, and the incidence of TD during or at EOF was 20%. Of 287 patients with IL-28B rs8099917 TT genotype, 29 (10.1%) had TAs before treatment, whereas the patients with other genotypes did not have TAs (P = 0.04). There was no significant difference of TD incidence during treatment or at EOF between the patients with different IL-28B genotypes. There was also no significant difference of sustained virologic response according to the presence of TAs, TD, or different manifestations of TD.

CONCLUSION

Taiwanese CHC patients with rs8099917 TT genotype had a higher incidence of TAs. The development of TAs and TD did not impact the treatment efficacy of PegIFN/RBV combination therapy.

Association of hepatitis C virus infection with risk of ESRD: a population-based study

BACKGROUND

The association between chronic hepatitis C virus (HCV) infection and end-stage renal disease (ESRD) has been widely debated.

STUDY DESIGN

National population-based cohort study.

SETTING & PARTICIPANTS

Insurance claims data from the Taiwan National Health Insurance Research Database in 2000-2005.

PREDICTOR

Chronic HCV infection as defined by the International Classification of Diseases, Ninth Revision, Clinical Modification.

OUTCOMES

ESRD as defined by the International Classification of Diseases, Ninth Revision, Clinical Modification.

RESULTS

We identified 6,291 adults with chronic HCV infection. The control group included 31,455 sex- and age-matched individuals without evidence of chronic hepatitis. The incidence of ESRD was 2.14-fold higher in patients with chronic HCV infection (HR, 1.53; 95% CI, 1.17-2.01; P = 0.002) than in patients without HCV infection. Age stratification analysis showed that patients aged 50-59 years with chronic HCV infection (HR, 7.77; 95% CI, 4.23-14.3; P < 0.001) had the highest risk of developing ESRD relative to patients aged 20-49 years without chronic HCV infection (interaction P < 0.001).

LIMITATIONS

Lack of clinical data.

CONCLUSIONS

Patients with chronic HCV infection are at greater risk of developing ESRD than individuals without chronic HCV infection. In addition, the risk of developing ESRD is highest in younger patients with HCV infection. Early renal screening programs should be initiated for this high-risk group of young individuals with chronic HCV infection.

Hepatitis C virus infection and kidney disease: a meta-analysis

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) infection and kidney disease are both highly prevalent diseases. The association between HCV and GN has been supported by previous research but little is known about the relationship between HCV and kidney disease.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A systematic review of the published medical literature was conducted to determine if HCV is associated with increased likelihood of kidney disease in the general population. A random-effects model was used to generate a summary estimate of the relative risk for kidney disease, defined as an estimated GFR <60 ml/min per 1.73 m(2) or proteinuria, with HCV across the published studies.

RESULTS

Nine clinical studies (817,917 unique individuals) were identified. Pooling of study results demonstrated the absence of a relationship between HCV seropositive status and reduced estimated GFR (adjusted relative risk, 1.12; 95% confidence interval, 0.91, 1.38; P=0.28) according to the random-effects model. HCV seropositive serology was an independent and significant risk factor for proteinuria (defined by urine dipstick test or spot urine albumin/creatinine ratio) in the general population, with a summary estimate for adjusted relative risk of 1.47 (95% confidence interval, 1.12, 1.94; P=0.006). Significant heterogeneity was observed between studies (Ri=0.82; P value by Q test, <0.001).

CONCLUSIONS

This meta-analysis shows that HCV is independently associated with proteinuria but not with reduced GFR in the general population. Substantial heterogeneity occurred.

Increased risk of cancer in chronic dialysis patients: a population-based cohort study in Taiwan

BACKGROUND

An increased incidence of cancer in chronic dialysis patients has not been confirmed in the Chinese population. The aim of this population-based study was to examine the risk of various types of cancers in chronic dialysis patients in Taiwan.

METHODS

Data of 92 348 chronic dialysis patients extracted from the National Health Institutes Research Database during 1997-2008 were analyzed. Patients newly diagnosed with end-stage renal disease, free of cancer and receiving dialysis for >3 months were eligible for inclusion in the study.

RESULTS

After a mean follow-up of 4.4 years, a new cancer was diagnosed in 4328 chronic dialysis patients. The standardized incidence ratio (SIR) of chronic dialysis patients was 1.4 [95% confidence interval (CI): 1.3-1.4] and annual incidence of cancer was 1.1%. A trend of an increased SIR of cancer was observed in young patients and within the first year of dialysis. Bladder cancer carried the highest SIR (SIR: 8.2, 95% CI: 6.7-9.9) and had the highest frequency (21.2%). Importantly, the frequency (15.3%) of liver cancer was the second highest and the SIR (SIR: 1.4, 95% CI: 1.2-1.5) of liver cancer in chronic dialysis patients was higher than that of their healthy counterparts. Unexpectedly, chronic dialysis patients had a significantly reduced risk of developing lung cancer.

CONCLUSION

Increased risk of cancer in chronic dialysis patients is confirmed in the Taiwanese population and it is necessary to develop different strategies for cancer screening in chronic dialysis patients among different ethnicities.