Development and validation of the AMMON-OHE model to predict risk of overt hepatic encephalopathy occurrence in outpatients with cirrhosis.

BACKGROUND & AIMS: Neuropsychological and psychophysical tests are recommended to assess the risk of overt hepatic encephalopathy (OHE), but their accuracy is limited. Hyperammonaemia is central in the pathogenesis of OHE, but its predictive utility is unknown. In this study, we aimed to determine the role of neuropsychological or psychophysical tests and ammonia, and to develop a model (AMMON-OHE) to stratify the risk of subsequent OHE development in outpatients with cirrhosis. METHODS: This observational, prospective study included 426 outpatients without previous OHE from three liver units followed for a median of 2.5 years. Psychometric hepatic encephalopathy score (PHES) <-4 or critical flicker frequency (CFF) <39 was considered abnormal. Ammonia was normalized to upper limit of normal (AMM-ULN) at the respective reference laboratory. Multivariable frailty competing risk and random survival forest analyses were performed to predict future OHE and to develop the AMMON-OHE model. External validation was carried out using 267 and 381 patients from two independent units. RESULTS: Significant differences were found in time-to-OHE (log-rank p <0.001) according to PHES or CFF and ammonia, with the highest risk in patients with abnormal PHES plus high AMM-ULN (hazard ratio 4.4; 95% CI 2.4-8.1; p <0.001 compared with normal PHES and AMM-ULN). On multivariable analysis, AMM-ULN but not PHES or CFF was an independent predictor of the development of OHE (hazard ratio 1.4; 95% CI 1.1-1.9; p = 0.015). The AMMON-OHE model (sex, diabetes, albumin, creatinine and AMM-ULN) showed a C-index of 0.844 and 0.728 for the prediction of a first episode of OHE in two external validation cohorts. CONCLUSIONS: In this study, we developed and validated the AMMON-OHE model, comprising readily available clinical and biochemical variables that can be used to identify outpatients at the highest risk of developing a first episode of OHE. IMPACT AND IMPLICATIONS: In this study, we aimed to develop a model to predict which patients with cirrhosis are at risk of developing overt hepatic encephalopathy (OHE). Using data from three units and including 426 outpatients with cirrhosis, we developed the AMMON-OHE model - comprising sex, diabetes, albumin, creatinine and ammonia levels - which demonstrated good predictive ability. The AMMON-OHE model performs better than PHES and CFF to predict the first episode of OHE in outpatients with cirrhosis. This model was validated in 267 and 381 patients from two independent liver units. The AMMON-OHE model is available online for clinical use.

High liver stiffness values by transient elastography related to metabolic syndrome and harmful alcohol use in a large Spanish cohort.

BACKGROUND AND AIMS: Transient elastography (TE) to estimate liver stiffness has proved to be very useful in the diagnosis of chronic liver disease. Here, we intend to evaluate its use in a large Spanish cohort. METHOD: Nested study within the PREVHEP-ETHON (Epidemiological sTudy of Hepatic infectiONs; NCT02749864) population-based, cross-sectional study performed between July 2015 and April 2017. An epidemiological questionnaire, laboratory tests and TE and anthropometric measurements were obtained. RESULTS: Data from 11,440 subjects were analyzed. Mean age was 50.3 (SD 12.4), of which 58.1% were women. 15.4% showed metabolic syndrome (NCEP ATP-III), 1.3% were positive for hepatitis C antibodies, 0.8% positive for HBsAg, 9.1% reported harmful use of alcohol. The prevalence of significant fibrosis (LSM > 8 kPa), suggestive compensated advanced chronic liver disease (cACLD) (LSM ≥ 10 kPa) and highly suggestive cACLD (LSM > 15 kPa) was 5.6%, 2.9%, and 1.2% respectively. Risk factors associated with significant fibrosis were age (OR 1.03 [1.02-1.04; p < 0.001]), sex (OR 0.8 [0.6-0.95; p = 0.02]), AST (OR 1.01 [1.01-1.02; p < 0.001]), GGT (OR 1.005 [1.003-1.006; p < 0.001]) and metabolic syndrome (OR 2.1 [1.7-2.6; p < 0.001]); risk factors associated with suggestive cACLD were age (OR 1.04 [1.02-1.05; p < 0.001]), AST (OR 1.01 [1.01-1.02; p < 0.001]), GGT (OR 1.006 [1.004-1.008; p < 0.001]), low platelets (OR 0.997 [0.994-0.999; p = 0.02]) and metabolic syndrome (OR 2.2 [1.6-2.9; p < 0.001]); and risk factors associated with highly suggestive cACLD were age (OR 1.04 [1.02-1.06; p = 0.001]), AST (OR 1.02 [1.01-1.03; p < 0.001]), GGT (OR 1.005 [1.003-1.007; p < 0.001]), low platelets (OR 0.993 [0.989-0.997; p < 0.001]), metabolic syndrome (OR 2.1 [1.4-3.3; p = 0.001]) and alcohol consumption (OR 1.8 [1.05-3.1; p = 0.03]). A non-negligible proportion of patients with normal transaminase levels, even with healthy transaminase levels, showed significant fibrosis and suggestive and highly suggestive cACLD 4.6% (95% CI 2.4-3.0), 2.1% (95% CI 1.9-2.5) and 1% (95% CI 0.7-1.1), respectively. CONCLUSION: We found high proportion of significant fibrosis and cACLD measured by TE. The most relevant factor associated with significant fibrosis was metabolic syndrome, however TE is still an imperfect method since it overestimated the fibrosis stage in 50% of the histologically analyzed subjects.

Update on epidemiology of hepatitis B in a low-endemic European country: There is still much to do.

The latest epidemiological data in Spain were obtained a decade ago and revealed a prevalence of hepatitis B surface antigen (HBsAg) of 0.7%; hence, updated epidemiological data are necessary. Our aim was to determine the prevalence of hepatitis B virus (HBV) infection, and to analyse associated factors and characterize chronic infection. A population-based, cross-sectional study was performed in Spain between July 2015 and April 2017. Participants from three regions were selected using two-stage conglomerate sampling and stratified by age. Anthropometric and demographic data were collected, and blood samples were taken to detect serological markers of HBV infection and to quantify HBV-DNA. The characterization of chronic HBV infection was based on ALT (alanine aminotransferase) values, HBV-DNA levels, and results of transient elastography. The overall prevalence rates of HBsAg and antibody to hepatitis B core antigen (anti-HBc) among 12 246 participants aged 20-74 years (58.4% females) were 0.6% (95% CI [0.4-0.7]) and 8.2% (7.7-8.7), respectively. The risk factors for HBV infection identified in the multivariate analysis were age, nosocomial risk, and non-Spanish nationality. Moreover, most patients HBsAg positive (76.6%) presented as hepatitis B e antigen (HBeAg)-negative chronic infection (formerly 'inactive carriers') and only 6 (9.4%) HBsAg carriers fulfilled current criteria for treatment. The current HBV burden in Spain remains low but virtually unchanged over the past 15 years. Increased efforts are still needed to reach the goal set forth by the World Health Organization (WHO) for HBV elimination by 2030.

Epidemiology of hepatitis C virus infection in a country with universal access to direct-acting antiviral agents: Data for designing a cost-effective elimination policy in Spain.

Accurate HCV prevalence estimates are necessary for guiding elimination policies. Our aim was to determine the HCV prevalence and assess the cost-effectiveness of a screen-and-treat strategy in the Spanish population. A population-based, cross-sectional study (PREVHEP-ETHON Cohort, Epidemiological sTudy of Hepatic infectiONs; NCT02749864) was performed from July 2015-April 2017. Participants from three Spanish regions were selected using two-stage conglomerate sampling, and stratified by age, with randomized subject selection. Anthropometric and demographic data were collected, and blood samples were taken to detect anti-HCV antibodies/quantify HCV RNA. The cost-effectiveness of the screening strategies and treatment were analysed using a Markov model. Among 12 246 participants aged 20-74 (58.4% females), the overall anti-HCV prevalence was 1.2% (95% CI 1.0-1.4), whereas the detectable HCV-RNA prevalence was 0.3% (0.2-0.4). Infection rates were highest in subjects aged 50-74 years [anti-HCV 1.6% (1.3-1.9), HCV RNA 0.4% (0.3-0.6]. Among the 147 anti-HCV + subjects, 38 (25.9%) had active infections while 109 (74.1%) had been cleared of infection; 44 (40.4%) had cleared after antiviral treatment, whereas 65 (59.6%) had cleared spontaneously. Overall, 59.8% of the anti-HCV + participants were aware of their serological status. Considering a cost of treatment of €7000/patient, implementing screening programmes is cost-effective across all age cohorts, particularly in patients aged 50-54 (negative incremental cost-effectiveness ratio which indicates a cost-saving strategy). The current HCV burden is lower than previously estimated, with approximately 25% of anti-HCV + individuals having an active infection. A strategy of screening and treatment at current treatment prices in Spain is cost-effective across all age cohorts.