Subendocardial viability ratio predicts cardiovascular mortality in chronic kidney disease patients.

BACKGROUND: The subendocardial viability ratio (SEVR), calculated by pulse wave analysis, is an index of myocardial oxygen supply and demand. Here we analyze the relation between SEVR and cardiovascular mortality in the chronic kidney disease (CKD) population of a post hoc analysis of a multicenter, prospective, randomized, nonblinded study. METHODS: We studied 212 consecutive asymptomatic outpatients receiving care at 12 nephrology clinics in south Italy. Inclusion criteria were age >18 years, 6 months of follow-up before the enrollment and stage 3-4 CKD. RESULTS: During follow-up, 34 subjects died, 29 of them for cardiovascular causes. SEVR correlated inversely with vascular calcifications (r = -0.37) and myocardial mass (r = -0.45); SEVR changed from 1.33 ± 0.24 to 1.36 ± 0.16 (p = NS; baseline and final values, respectively) in living patients, and from 1.16 ± 0.31 to 0.68 ± 0.26 in deceased patients (p < 0.001). Kaplan-Meier curves show that that a greater reduction of SEVR values during the study (third tertile) significantly predicts cardiovascular mortality (p < 0.0001). CONCLUSIONS: This post hoc analysis shows that a reduction of SEVR values impacts cardiovascular mortality in CKD patients.

Serum hepatitis B surface antigen monitoring in long-term lamivudine-treated hepatitis B virus patients.

Serum hepatitis B virus surface antigen (HBsAg) levels have been suggested to predict interferon response in chronic hepatitis B. A few data are available on the role of HBsAg measurement in nucleos(t)ide analogues (NA) treatment. We retrospectively investigated the relation between HBsAg changes and main treatment outcomes during long-term lamivudine treatment in hepatitis e antigen (HBeAg)-negative chronic hepatitis B. A total of 42 HBeAg-negative patients were consecutively enrolled in an open-label study on long-term lamivudine monotherapy (150 mg/die). Serum HBsAg levels were quantified every 6 months by Architect assay (Abbott Diagnostics). HBV-DNA was quantified quarterly by real-time PCR (Roche Diagnostics). The median duration of lamivudine treatment was 66 months (20-153). One patient (2%) was a primary nonresponder, 35 (83%) developed virological breakthrough (VB) and the remaining six patients (14%) were classified as long-term on-treatment responders. During treatment, HBsAg levels decreased only in long-term on-treatment responders, while no changes were observed in resistant patients. Failure to achieve a decrease of 0.7 log(10) IU/mL in serum HBsAg at month six of lamivudine had a positive predictive value of developing VB of 90% and a negative predictive value of 100%. These high predictive values were also maintained in the subgroup of patients negative for HBV-DNA at month six. The results of this study with a small sample size suggest a role of on-treatment HBsAg quantification in the management of lamivudine-treated patients. If validated prospectively in a larger patient cohort, HBsAg measurements would be a useful adjunct to optimize antiviral therapy.

Hepatitis C Virus-related chronic liver disease in elderly patients: an Italian cross-sectional study.

Chronic hepatitis C virus (HCV) infection has been poorly investigated in the elderly. The aim of this study was to identify the age-specific characteristics of chronic hepatitis C by comparing patients > or =65 years with those <65 years. A cross-sectional study was performed on data collected from consecutive outpatients referred for the first time to two tertiary outpatient clinics for liver diseases located in Bologna (Northern Italy) and Paola, Cosenza (Southern Italy) over a two-year period. A total of 560 anti-HCV and HCV-RNA positive patients were enrolled, of whom 174 (31%) were 65 years or older. The proportion of older patients was significantly higher in the Southern Italy centre, accounting for more than 40%. Comparison of younger and older groups showed that 51% patients > or =65 years had advanced liver disease (liver cirrhosis or hepatocellular carcinoma) compared with 26% younger patients (P < 0.0001). About half of the patients > or =65 years were not aware of their anti-HCV positive status, even if they tended to be more symptomatic than the younger group. By multivariate analysis, age > or = 65 years, alcohol consumption and diabetes were independently associated with advanced liver disease. Overall, 34 out of 174 patients (20%) > or =65 years had received antiviral treatment compared with 122 out of 386 (32%) younger patients (P = 0.003). Our results further emphasize the notion that chronic hepatitis C is becoming a disease of the elderly and that elderly patients with chronic HCV infection often have severe and underestimated disease.

[Epidemiology of cardiovascular disease in CKD-MBD]. / Epidemiologia della patologia cardiovascolare nella CKD-MBD.

Evidence has been accumulating in recent years that chronic kidney disease (CKD) is a common disease associated with a high risk of morbidity and mortality. Cardiovascular complications are the leading cause of death in patients with CKD, and the risk of cardiovascular mortality is 10-30-fold higher in dialysis patients than in age-, gender- and race-matched controls. On the basis of this evidence it has been suggested that the cardiovascular risk profile of CKD patients is different from that of the general population, resulting from a complex and peculiar interaction of risk factors. In fact, traditional risk factors such as hypertension, aging, smoking, diabetes, and lipid disorders do not fully explain the high frequency of cardiovascular disease in CKD, so other factors must be involved in the high mortality rate in uremic patients. In this article we will provide an overview of the epidemiology of the cardiovascular risk factors in CKD. Among the non-traditional risk factors we have focused particularly on those related to mineral metabolism, which contribute the high rates of cardiovascular events observed in CKD.

Quantifiers for randomness of chaotic pseudo-random number generators.

We deal with randomness quantifiers and concentrate on their ability to discern the hallmark of chaos in time series used in connection with pseudo-random number generators (PRNGs). Workers in the field are motivated to use chaotic maps for generating PRNGs because of the simplicity of their implementation. Although there exist very efficient general-purpose benchmarks for testing PRNGs, we feel that the analysis provided here sheds additional didactic light on the importance of the main statistical characteristics of a chaotic map, namely (i) its invariant measure and (ii) the mixing constant. This is of help in answering two questions that arise in applications: (i) which is the best PRNG among the available ones? and (ii) if a given PRNG turns out not to be good enough and a randomization procedure must still be applied to it, which is the best applicable randomization procedure? Our answer provides a comparative analysis of several quantifiers advanced in the extant literature.

[The usefulness of Cochrane systematic reviews in nephrology]. / Le principali revisioni sistematiche Cochrane all'attenzione della Societa' Italiana di Nefrologia: a cosa servono?

Systematic reviews (SRs) of the literature are clinical research studies carried out according to rigorous methodological criteria. They are aimed at searching, critically appraising and summarizing all studies with similar characteristics that address the same research question. The Cochrane Collaboration is the main institution that coordinates the production of SRs. The Cochrane Renal Group is one of the 50 research groups of the Cochrane Collaboration and is in charge of SRs in nephrology. This group compiled the Renal Health Library, an annually updated collection of SRs (Cochrane and not) and randomized controlled trials in nephrology, dialysis and renal transplantation. We searched the Renal Health Library to identify SRs useful to answer clinical questions in patients with renal disease and/or following kidney transplant. The SRs identified were summarized and the results were expressed as relative risk, weighted mean difference, standardized mean difference, and 95% confidence intervals. Since the number of randomized controlled trials is quite large and SRs are a reliable summary of the scientific evidence, their distribution is of paramount importance. Here we show several clinical cases where related SRs in the Renal Health Library provide useful guidance for treatment.

Alcohol and viral hepatitis: a mini-review.

Due to their high prevalence in the general population, alcohol use and abuse can be associated with hepatitis B and C virus infections and it has been demonstrated that alcohol plays a role as a co-morbid factor in the development of liver disease. There is evidence that alcohol abuse accelerates the progression of liver fibrosis and affects the survival of patients with chronic hepatitis C. The mechanism by which alcohol worsens hepatitis C virus-related liver disease has not been fully clarified, but enhanced viral replication, increased oxidative stress, cytotoxicity and impairment of immune response could play a relevant role. Alcohol abuse also seems to reduce both sensitivity to interferon and adherence to treatment. It sounds reasonable to presume that the mechanisms enhancing liver damage in patients affected by hepatitis B are similar to those involved in hepatitis C virus infection. However, more studies are warranted to improve our knowledge about the interaction between alcohol intake and hepatitis B virus infection. In conclusion alcohol abuse is associated with an accelerated progression of liver injury, leading to an earlier development of cirrhosis, higher incidence of hepatocellular carcinoma, and higher mortality. Abstinence could reverse some of these deleterious effects.

[Methimazole versus methimazole and diphosphonates in hyperthyroid and osteoporotic patients]. / Metimazolo versus metimazolo e bifosfonatiin pazienti ipertiroidei con osteoporosi.

AIM: It is well-know that hyperthyroidism is one of the key causes of secondary osteoporosis. High values of thyroid hormones increase the bone mineral turnover speed by promoting osteoclastic and osteoblastic activities. The aim of our study is to evaluate the increase of bone mineral density (BMD) in osteoporotic and hyperthyroid patients treated with only antithyroid drugs versus patients treated with antithyroid drugs and diphosphonates. METHODS: Twenty-six elderly male patients, 65-75 years, were selected. In all these patients, thyroid function (FT3, FT4, TSH, Tg, AbTg, AbTPO) was evaluated at baseline and after 6 and 12 months from the start of medical treatment; the following were evaluated: BMD, calcium serum, phosphorus serum, alkaline phosphatase, PTH and 24 hours urinary calcium, phosphorus and hydroxyprolin. Thirteen patients (group 1) were treated with antithyroid drugs (methimazole 5-20 mg/die/os) and diphosphonates (alendronate 10 mg/die/os). The control group of 13 patients (group 2) was treated with antithyroid drugs only. RESULTS: After 6 months of treatment, the patients of group 1 showed a mean increase of 2.5% in lumbar spine BMD compared with a mean increase of 0.3% in group 2 (p<0.01). After 12 months, group 1 showed a mean increase of 6.2% in lumbar spine BMD, compared with a mean increase of 2% in group (p<0.001). CONCLUSIONS: The combination of antithyroid and diphosphonates drugs appears to be more efficacious than antithyroid therapy alone for the treatment of osteoporosis in male hyperthyroid patients.