Prognostic Value of Right Ventricular Strain Using Speckle-Tracking Echocardiography in Pulmonary Hypertension: A Systematic Review and Meta-analysis

Background

Right ventricular (RV) strain imaging using speckle-tracking echocardiography (STE) is a quantitative method of assessing RV systolic function that has shown prognostic utility in patients with pulmonary hypertension (PH). However, its prognostic value for a large and mixed PH population remains poorly defined.

Does Vitamin E Improve the Outcomes of Pediatric Nonalcoholic Fatty Liver Disease? A Systematic Review and Meta-analysis

Background and Aims:

To systemically evaluate the efficacy of adjuvant vitamin E on the outcomes of nonalcoholic fatty liver disease (NAFLD) and/or nonalcoholic steatohepatitis (NASH) in children.

Materials and Methods:

We searched MEDLINE, PUBMED, EMBASE, the Cochrane Central Register Controlled Trials, and the Cochrane Database of Systematic Reviews over the period between January 1980 and September 2012 for the studies that examined the role of adjuvant vitamin E given at any dose or duration, alone or in combination with other interventions, on the outcome of pediatric NAFLD. The outcomes are alanine aminotransferase (ALT) normalization and histological improvement.

Results:

Five randomized trials were eligible to be included in our analysis, with a total of 270 participants. There was no statistically significant difference in the effect of adjuvant vitamin E on normalizing serum ALT [risk ratio (RR) =1.18, confidence interval (CI) =0.92-1.53, P = 0.77 for heterogeneity, I² = 0%]. Sensitivity analysis showed that using higher doses of vitamin E, a longer duration of therapy or adding vitamin C did not change the effect on the measured outcome. Only two studies looked at histological changes as an outcome. We observed substantial heterogeneity between the two studies.

Conclusions:

Our meta-analysis did not find a significant effect of adjuvant vitamin E over placebo in normalizing serum ALT. Data on the long-term effect of adjuvant vitamin E on histological improvements in NAFLD patients are still lacking. Larger, well-designed randomized controlled trials (RCTs) in children with histological endpoints are still needed to answer this question.     

Interferon for Hepatitis C Virus in Hemodialysis—an Individual Patient Meta-analysis of Factors Associated with Sustained Virological Response

Background and objectives: Hepatitis C virus (HCV) infection is prevalent in hemodialysis patients and causes excess mortality. Interferon (IFN) treatment of chronic HCV infection in hemodialysis patients results in high sustained virological response (SVR) rates 6 mo after treatment. The authors aimed to identify factors associated with SVR in hemodialysis patients through analysis of individual patient data obtained from systematic review of published literature.Design, setting, participants & measurements: Medline was searched from 1966 through February 2009, and prospective studies describing IFN treatment of hemodialysis patients with chronic HCV infection with published individual patient data were included. To identify factors associated with SVR, logistic regression was applied with adjustment for study.Results: Twenty studies of IFN treatment provided data on 428 patients. Overall SVR was 45% and in univariate analyses was higher with: 1) three million units or higher three times weekly of IFN; 2) treatment for at least 6 mo; 3) treatment completion; 4) lower baseline HCV RNA; 5) female gender; and 6) early virological negativity. Although limited by missing data, these relationships persisted in multivariate regression.Conclusions: SVR is more likely with larger IFN dose, longer treatment duration, treatment completion, female gender, lower HCV RNA and early virological negativity. For appropriate treatment candidates, regimens should consist of three million units of IFN three times weekly for at least 6 mo, with patients encouraged to complete the full course.Hepatitis C virus (HCV) infects an estimated 170 million people worldwide (1). The prevalence of HCV in hemodialysis (HD) patients ranges from 3 to 23% in developed countries (2) and exceeds 50% in some developing countries (3). HCV-infected HD patients have higher mortality rates than noninfected HD patients, with reported relative risks from 1.25 to 1.57 (4,5). Untreated, spontaneous viral clearance occurs in only 0.5% of chronic HCV-infected patients per year (6). The standard measure of treatment success, sustained virological response (SVR), is defined as achieving HCV RNA negativity six months after treatment completion. In non-HD patients, interferon (IFN) monotherapy achieves SVR in 9 to 22% of patients (7–9) but combination pegylated IFN and ribavirin achieves SVR in 50 to 60% (10,11). However, IFN and ribavirin are associated with significant toxicity including influenza-like symptoms, anemia and depression with IFN (7–9), and hemolytic anemia with ribavirin (7,8).Most studies of HCV-infected HD patients have investigated IFN monotherapy. Only recently, studies have explored pegylated IFN or ribavirin (12–18). IFN treatment after kidney transplantation is associated with increased rates of allograft rejection (19,20), so treatment before transplantation is advised (21,22). Our recent meta-analysis of summary data in HCV-infected HD patients demonstrated an overall SVR rate of 41% with IFN (22), higher than rates in IFN-treated non-HD patients (7,8), but rates of treatment discontinuation due to adverse events were also higher (22).Identifying factors associated with a higher likelihood of SVR among HD patients has important implications for selecting treatment candidates and the optimal treatment regimen. In non-HD patients, higher SVR rates are associated with younger age, female gender, lower patient weight, HCV genotypes other than 1, lower baseline HCV RNA, and absence of cirrhosis on liver biopsy (7–11). Early virological response (EVR), defined as a 2-log₁₀ or larger decrease in HCV RNA by the 12^th week of treatment, is a powerful predictor of SVR (23,24).We investigated whether these previously identified factors associated with SVR in non-HD patients could be validated in the HD population. The majority of studies of IFN in HD patients reported individual patient data, allowing us to extend our prior subgroup analysis and meta-regression of summary data (22) to identify factors associated with SVR.     

Yoga for Asthma? A Systematic Review of Randomized Clinical Trials

Objective. The objective of this systematic review was to assess the effectiveness of yoga as a treatment option for asthma. Method. Seven databases were searched from their inception to October 2010. Randomized clinical trials (RCTs) and non-randomized clinical trials (NRCTs) were considered, if they investigated any type of yoga in patients with asthma. The selection of studies, data extraction, and validation were performed independently by two reviewers. Results. Six RCTs and one NRCT met the inclusion criteria. Their methodological quality was mostly poor. Three RCTs and one NRCT suggested that yoga leads to a significantly greater reduction in spirometric measures, airway hyperresponsivity, dose of histamine needed to provoke a 20% reduction in forced expiratory volume in the first second, weekly number of asthma attacks, and need for drug treatment. Three RCTs showed no positive effects compared to various control interventions. Conclusions. The belief that yoga alleviates asthma is not supported by sound evidence. Further, more rigorous trials are warranted.