The aim of this study is to know the liver stiffness measurement (LSM) cutoffs for different stages of liver fibrosis in chronic hepatitis B (CHB) and to investigate the effect of alanine ...aminotransferase (ALT) on LSM. We prospectively studied consecutive CHB patients undergoing liver biopsy and transient elastography examinations. Diagnostic performance of LSM for different degrees of liver fibrosis was evaluated. One hundred and sixty‐one CHB patients with adequate liver biopsy sample size were studied. Area under receiver operating characteristics curves of LSM for no fibrosis (F0 vs F1–4), bridging fibrosis (F0–2 vs F3–4) and liver cirrhosis (F0–3 vs F4) was 0.80 (95% CI: 0.68–0.92), 0.87 (95% CI: 0.82–0.93) and 0.93 (95% CI: 0.89–0.97) respectively. For liver cirrhosis, these optimal cutoff values were 8.4 kPa (98% sensitivity), 9.0 kPa (maximum sum of sensitivity and specificity), 13.4 kPa (94% specificity) and 13.4 kPa (maximum diagnostic accuracy, 85%) respectively. Patients with the same fibrosis staging but higher ALT levels tend to have higher LSM, and the diagnostic performance for low stage fibrosis was most seriously affected when ALT was elevated. Different LSM cutoff values and algorithms were derived for normal and elevated ALT levels. Based on these algorithms, liver biopsy can be avoided in 62% and 58% of patients with normal and elevated ALT respectively. In conclusion, transient elastography is a reasonable noninvasive tool to substitute liver biopsy among the lowest and highest risk patients for the assessment of liver fibrosis.
Summary
Background
A meta‐analysis on the risk of hepatocellular carcinoma (HCC) among hepatitis B virus (HBV) genotypes is warranted as the current data are conflicting.
Aim
To investigate the ...relative risk of HCC among the four major HBV genotypes (A–D).
Methods
A meta‐analysis was performed based on literature search from electronic databases and bibliography between 1950 and 2012. All s with keywords ‘hepatitis B’, ‘hepatocellular carcinoma’ and ‘genotype’ were screened. Studies were included if they reported HBV genotype as an exposure and HCC as an outcome.
Results
Nine hundred and eighty‐eight s were found through literature search, among them 43 studies were eligible for this meta‐analysis. A total of 14 545 patients with an average age of 43 years were included; 71% were male patients and 17% had cirrhosis. In 33 studies, HCC was found in 1541/6060 (25%) genotype C vs. 550/4417 (12%) genotype B HBV‐infected patients odds ratio (OR) = 2.05, 95% confidence interval (CI) = 1.52–2.76, P < 0.001. No difference in the risk of HCC was found among genotype A (71/517, 14%) vs. genotype D (170/1506, 11%) HBV‐infected patients in 14 studies (OR = 0.94, 95% CI = 0.67–1.32). In 10 studies, the risk of HCC was also found higher among genotype C (498/1659, 30%) than genotype A&D (103/1403, 7%) HBV‐infected patients (OR = 2.34, 95% CI = 1.63–3.34, P < 0.001). Subgenotype Ce and Cs HBV‐infected patients had similar risk on HCC (OR = 1.13, 95% CI = 0.76–1.67, P = 0.54). On funnel plot analysis, there was no significant publication bias in all comparisons.
Conclusion
Genotype C hepatitis B virus is associated with a higher risk of hepatocellular carcinoma than other major hepatitis B virus genotypes.
Metabolic syndrome is associated with non-alcoholic steatohepatitis and cryptogenic cirrhosis. Whether metabolic syndrome affects the severity of chronic hepatitis B (CHB) is unclear.
We aimed to ...study the relationship between metabolic syndrome and the risk of liver cirrhosis in patients with CHB.
We prospectively recruited patients with CHB from primary care and hospital clinics for liver stiffness measurement (LSM) with transient elastography to diagnose early cirrhosis. Probable cirrhosis was defined as LSM >or=13.4 kPa. We analysed a subgroup of patients with paired LSM and liver biopsies to validate the accuracy of LSM.
1466 patients had reliable LSM and 134 (9%) patients had adequate liver biopsy. 188 (13%) patients had metabolic syndrome. Histological liver cirrhosis was present in 32/134 (24%) patients. Histological liver cirrhosis was more common among patients who had metabolic syndrome (38%) versus those who did not (11%, p<0.001). The specificity of probable cirrhosis on LSM for histological cirrhosis was 94%. Probable cirrhosis was present in 187 (13%) patients. Metabolic syndrome was more prevalent in patients with probable cirrhosis (24%) than those without cirrhosis (11%, p<0.001). After adjustment for anthropometric, biochemical and virological factors, metabolic syndrome remained an independent factor associated with probable cirrhosis (odds ratio 1.7, 95% confidence interval (CI) 1.1 to 2.6). The odds ratios of probable cirrhosis were 1.4 (95% CI, 0.9 to 2.3), 2.6 (95% CI, 1.7 to 4.3), 4.1 (95% CI, 2.4 to 7.1), 4.0 (95% CI, 1.9 to 8.4) and 5.5 (95% CI, 1.8 to 16.7) in patients with one, two, three, four and five components of metabolic syndrome, respectively.
Metabolic syndrome is an independent risk factor of liver cirrhosis in CHB.
Summary
Background
On‐treatment monitoring of serum hepatitis B virus (HBV) DNA to guide treatment strategy for patients on entecavir has received little attention.
Aim
To investigate the predictive ...value of on‐treatment HBV DNA levels for responses to entecavir.
Methods
This was a retrospective cohort study among nucleos(t)ide analogue‐naïve HBV‐infected patients on entecavir with a minimum follow‐up of 2 years. Maintained virological suppression was defined as undetectable HBV DNA (<20 IU/mL) until the last visit. Genotypic drug resistance was screened by using the INNO‐LiPA DR assay.
Results
A total of 440 chronic hepatitis B patients (160 HBeAg‐positive) followed for 34 ± 9 months were included. The cumulative probability of maintained virological suppression at year 1, 2 and 3 were 76.5%, 83.0% and 88.3% respectively. On multivariate analysis, lower baseline HBV DNA, undetectable HBV DNA at month 12 and negative HBeAg were the independent predictors of maintained virological suppression. M12 responders (who had undetectable HBV DNA at month 12) had higher probability of maintained virological suppression at 3 years (99.1%) as compared to non responders (57.5%; P < 0.001). The cumulative probability of HBeAg‐seroconversion at year 1, 2 and 3 were 19.0%, 27.2% and 33.5% respectively. M12 responders had higher probability of HBeAg‐seroconversion at 3 years (43.2%) than the non responders (19.0%; P = 0.003). M12 responders had lower probability of drug resistance at 3 years (0%) than the non responders (2.6%; P = 0.004).
Conclusion
Month 12 HBV DNA responses could predict the probability of maintained virological suppression, HBeAg‐seroconversion and risk of drug resistance among patients on entecavir treatment at 3 years.
Aliment Pharmacol Ther 2010; 32: 1059–1068
Summary
Background The long‐term benefit of interferon‐alfa (IFN‐α) treatment in preventing various hepatic complications is not certain.
Aim To study the ...effects of IFN‐α on reducing the risk of developing overall hepatic events (hepatocellular carcinoma, cirrhotic complications and liver‐related mortality) in chronic hepatitis B patients.
Methods Randomized controlled trials, case–control studies and cohort studies were retrieved from electronic databases and conference s. Relative risks (RRs) of different hepatic complications among patients treated by IFN‐α vs. no treatment or placebo were studied.
Results Eleven studies were identified totalling 975 patients treated by IFN‐α vs. 1147 untreated controls for analysis. Patients were treated by IFN‐α for 1–24 months with a post‐treatment follow‐up of 1–13 years. Treatment by IFN‐α reduced the risk of overall hepatic events (RR 0.55, 95% confident interval or CI 0.43–0.70, P < 0.001) and cirrhotic complications (RR 0.46, 95% CI 0.32–0.67, P < 0.001) by 45% and 54% respectively. Patients who responded to IFN‐α had more profound reduction in overall hepatic events (RR 0.20, 95% CI 0.05–0.87, P = 0.03) and cirrhotic complications (RR 0.19, 95% CI 0.09–0.38, P < 0.001) vs. the untreated controls.
Conclusion Interferon‐alfa treatment reduces the risk of hepatic events particularly among responders to treatment.
We consider an optimal control problem with a nonlinear continuous inequality constraint. Both the state and the control are allowed to appear explicitly in this constraint. By discretizing the ...control space and applying a novel transformation, a corresponding class of semi-infinite programming problems is derived. A solution of each problem in this class furnishes a suboptimal control for the original problem. Furthermore, we show that such a solution can be computed efficiently using a penalty function method. On the basis of these two ideas, an algorithm that computes a sequence of suboptimal controls for the original problem is proposed. Our main result shows that the cost of these suboptimal controls converges to the minimum cost. For illustration, an example problem is solved.
There is a growing concern that the use of anti-hypertensives may be associated with an increased risk of cancer, but it remains uncertain for the association between anti-hypertensives and lung ...cancer risk, as well as their interaction with aspirin in chemoprotective effects.
The goal of this study is to assess the association between anti-hypertensives use and the risk of lung cancer, as well as the chemopreventive impacts from the combination usage of aspirin and anti-hypertensives. A retrospective cohort study was conducted based on all the public hospital electronic medical records in Hong Kong. Patients with prescription records of anti-hypertensives (ACEi/ARB, CCB, β-blocker,α-blocker) and/or aspirin were included as the exposure groups. Using the Cox proportional hazards model with inverse probability weighting, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for lung cancer risk from anti-hypertensives usage or combination usage of aspirin with anti-hypertensives. The likelihood ratio test and interaction model were adopted for exploring the interaction effects with aspirin.
A total of 6592 and 84,116 lung cancer cases were identified from the groups of anti-hypertensives users and anti-hypertensives users with aspirin, respectively. The group of non-aspirin patients who received anti-hypertensives showed a significantly lower risk of lung cancer (HR: 0.63, 95% CI: 0.60-0.66), compared to those without anti-hypertensives. When aspirin and α-blocker were used simultaneously, it could lower the risk of lung cancer significantly (HR: 0.53, 95% CI: 0.34-0.84). Moreover, the lower risk of lung cancer persisted with a longer follow-up period of anti-hypertensives usage. Combination usage with aspirin in the users of ACEi/ARB, CCB, and α-blocker showed significant interaction effects. However, the smoking effect could not be eliminated in this analysis.
Anti-hypertensive treatment was associated with a lower risk of lung cancer, which is associated with the anti-hypertensives exposure period. The potential interaction on the chemopreventive influence from combination usage of α-blocker and aspirin might exist. More corroborations on these findings are needed to focus on the different settings in future studies.
Visit-to-visit blood pressure variability (BPV) has been shown to be a predictor of cardiovascular disease. We aimed to classify the BPV levels using different machine learning algorithms. ...Visit-to-visit blood pressure readings were extracted from the SPRINT study in the United States and eHealth cohort in Hong Kong (HK cohort). Patients were clustered into low, medium, and high BPV levels with the traditional quantile clustering and 5 machine learning algorithms including K-means. Clustering methods were assessed by Stability Index. Similarities were assessed by Davies-Bouldin Index and Silhouette Index. Cox proportional hazard regression models were fitted to compare the risk of myocardial infarction, stroke, and heart failure. A total of 8133 participants had average blood pressure measurement 14.7 times in 3.28 years in SPRINT and 1094 participants who had average blood pressure measurement 165.4 times in 1.37 years in HK cohort. Quantile clustering assigned one-third participants as high BPV level, but machine learning methods only assigned 10% to 27%. Quantile clustering is the most stable method (stability index: 0.982 in the SPRINT and 0.948 in the HK cohort) with some levels of clustering similarities (Davies-Bouldin Index: 0.752 and 0.764, respectively). K-means clustering is the most stable across the machine learning algorithms (stability index: 0.975 and 0.911, respectively) with the lowest clustering similarities (Davies-Bouldin Index: 0.653 and 0.680, respectively). One out of 7 in the population was classified with high BPV level, who showed to have higher risk of stroke and heart failure. Machine learning methods can improve BPV classification for better prediction of cardiovascular diseases.
A pressure sensor based on irregular microhump patterns has been proposed and developed. The devices show high sensitivity and broad operating pressure regime while comparing with regular ...micropattern devices. Finite element analysis (FEA) is utilized to confirm the sensing mechanism and predict the performance of the pressure sensor based on the microhump structures. Silicon carbide sandpaper is employed as the mold to develop polydimethylsiloxane (PDMS) microhump patterns with various sizes. The active layer of the piezoresistive pressure sensor is developed by spin coating PEDOT:PSS on top of the patterned PDMS. The devices show an averaged sensitivity as high as 851 kPa−1, broad operating pressure range (20 kPa), low operating power (100 nW), and fast response speed (6.7 kHz). Owing to their flexible properties, the devices are applied to human body motion sensing and radial artery pulse. These flexible high sensitivity devices show great potential in the next generation of smart sensors for robotics, real‐time health monitoring, and biomedical applications.
Polydimethylsiloxane‐molded irregular microhump structures can be used as a highly sensitive pressure sensor. How to achieve different density and size of microhumps by using silicon carbide sand paper and characterize their response under external loading is described. The irregular structure can extend the loading pressure to higher than 10 kPa without saturation. The devices with excellent stability show promising applications in the fields of biomedical and health monitoring systems.
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