An agonist of CXCR4 induces a rapid recovery from the neurotoxic effects of Vipera ammodytes and Vipera aspis venoms.

People bitten by Alpine vipers are usually treated with antivenom antisera to prevent the noxious consequences caused by the injected venom. However, this treatment suffers from a number of drawbacks and additional therapies are necessary. The venoms of Vipera ammodytes and of Vipera aspis are neurotoxic and cause muscle paralysis by inducing neurodegeneration of motor axon terminals because they contain a presynaptic acting sPLA2 neurotoxin. We have recently found that any type of damage to motor axons is followed by the expression and activation of the intercellular signaling axis consisting of the CXCR4 receptor present on the membrane of the axon stump and of its ligand, the chemokine CXCL12 released by activated terminal Schwann cells. We show here that also V. ammodytes and V. aspis venoms cause the expression of the CXCL12-CXCR4 axis. We also show that a small molecule agonist of CXCR4, dubbed NUCC-390, induces a rapid regeneration of the motor axon terminal with functional recovery of the neuromuscular junction. These findings qualify NUCC-390 as a promising novel therapeutics capable of improving the recovery from the paralysis caused by the snakebite of the two neurotoxic Alpine vipers.

Simultaneous detection of Aspergillus nidulans, Aspergillus luchuensis and Lichtheimia sp. in a bovine abortion.

Abortion in dairy cattle may be caused by infectious (viruses, fungi and protozoa) and non-infectious causes mostly related to bad management practices and genetic factors. Recently, the significant contribution of mycotic infection to bovine abortion has been recognized. This report describes an abortion case in a Chianina cow due to Aspergillus nidulans, Aspergillus luchuensis and Lichtheimia sp. diagnosed by histology, cytology, culture and molecular assays. A mixed infection due to more than one fungus in abortion is rarely demonstrated. To our knowledge, this is the first case of bovine abortion caused by co-infection with three different moulds.

Heritability of arterial stiffness and carotid intima-media thickness: an Italian twin study.

BACKGROUND AND AIMS: Carotid intima-media thickness (IMT) and arterial stiffness parameters, including aortic augmentation index (AIx) and pulse wave velocity (PWV), are independent predictors of stroke and cardiovascular disease. Genetic effects on these traits were never explored in a Mediterranean country. The present study aims to quantify the contribution of genes, environment and age to carotid IMT and aortic Aix and PWV. METHODS AND RESULTS: The twin design was used. A total of 348 adult twins from the Italian Twin Register underwent measurements of carotid IMT and aortic PWV and AIx in three university hospitals located in Rome, Padua and Perugia. Carotid IMT was measured by B-mode ultrasound, aortic PWV and AIx by Arteriograph. Genetic modelling was performed to decompose total variance of traits into genetic, shared and unshared environmental and age components. For each phenotype, the best-fitting model included additive genetic, unshared environmental and age effects. For IMT, heritability was 0.32 (95% confidence interval (CI): 0.25-0.38), unshared environmental component was 0.25 (0.18-0.32) and age contribution was 0.44 (0.39-0.49). For AIx and PWV, heritabilities were 0.42 (0.29-0.55) and 0.49 (0.35-0.62), unshared environmental components were 0.31 (0.22-0.44) and 0.37 (0.26-0.51) and age contributions were 0.27 (0.16-0.39) and 0.14 (0.06-0.24), respectively. CONCLUSION: This study shows substantial genetic and unshared environmental influences on carotid intima-media thickness and arterial stiffness and confirms the relevant role of age in the aetiology of these traits. Further support is provided for prevention and health promotion strategies based on modifiable factors.

Discordant twins as a tool to unravel the aetiology of bipolar disorder.

This editorial focuses on discordant twins as a valuable epidemiological design for psychiatric aetiological research. First, we summarise the advantages and strengths of this design over the classical matched case-control study. Then, we draw attention to the use of this method in bipolar disorder, revising previous discordant-twin studies. A future greater use of discordant twins is desirable to gain further relevant insights in the aetiology of bipolar disorder.

Health status and 6 years survival of 552 90+ Italian sib-ships recruited within the EU Project GEHA (GEnetics of Healthy Ageing).

In a scenario of increasing life expectancy worldwide, it is mandatory to identify the characteristics of a healthy aging phenotype, including survival predictors, and to disentangle those related to environment/lifestyle versus those related to familiarity/genetics. To this aim we comprehensively characterised a cohort of 1,160 Italian subjects of 90 years and over (90+, mean age 93 years; age range 90-106 years) followed for 6 years survival, belonging to 552 sib-ships (familiar longevity) recruited (2005-2008) within the EU-funded GEHA project in three Italian geographic areas (Northern, Central and Southern Italy) different for urban/rural and socio-economical characteristics. On the whole, the following factors emerged as significant predictors of survival after 90 years of age: absence of cognitive impairment and physical disability, high hand grip strength scores and body mass index (BMI) values, "excellent/good" self-reported health, high haemoglobin and total cholesterol levels and low creatinine levels. These parameters, excluding BMI values, were also significantly associated within sib-ships, suggesting a strong familial/genetic component. Geographical micro-heterogeneity of survival predictors emerged, such as functional and physical status being more important in Southern than in Central and Northern Italy. In conclusion, we identified modifiable survival predictors related to specific domains, whose role and importance vary according to the geographic area considered and which can help in interpreting the genetic results obtained by the GEHA project, whose major aim is the comprehensive evaluation of phenotypic and genetic data.

Psychological well-being (PWB): a natural life outlook? An Italian twin study on heritability of PWB in young adults.

BACKGROUND: To date, the genetic and environmental architecture of the dimensions of psychological well-being (PWB) remains unexplored. METHOD: PWB of 742 twins aged 23-24 years and enrolled in the Italian Twin Registry was assessed with the three-item version of Ryff's Scales of Psychological Well-Being (SPWB). These scales include items for evaluating the PWB dimensions of self-acceptance, positive relations with others, autonomy, environmental mastery, purpose in life, and personal growth. A twin design was used to obtain correlations in the PWB dimensions for monozygotic (MZ) and dizygotic (DZ) twins and to estimate the contribution of genetic and environmental factors to variation and covariation in the dimensions. RESULTS: Genetic factors explained moderate to substantial proportions of variance in the six SPWB dimensions, with heritability estimates between 37% and 64%. The estimates of genetic correlations were very high (range 0.77-0.99), indicating that genetic factors that influence the expression of the different dimensions of PWB may be shared to a large extent. Non-shared environmental correlations ranged from substantial to high, with the exception of the correlation between autonomy and the dimensions of purpose in life, self-acceptance and personal growth. CONCLUSIONS: This study presents a twin analysis of PWB measured by the SPWB dimensions; it was found that both genes and non-shared environment play a role in individual differences. The genetic and non-shared environmental correlations between SPWB dimensions suggest that common underlying genetic and non-shared environmental factors influence the expression of the different facets of PWB.

Permanent diabetes during the first year of life: multiple gene screening in 54 patients.

AIMS/HYPOTHESIS: The aim of this study was to investigate the genetic aetiology of permanent diabetes mellitus with onset in the first 12 months of age. METHODS: We studied 46 probands with permanent, insulin-requiring diabetes with onset within the first 6 months of life (permanent neonatal diabetes mellitus [PNDM]/monogenic diabetes of infancy [MDI]) (group 1) and eight participants with diabetes diagnosed between 7 and 12 months of age (group 2). KCNJ11, INS and ABCC8 genes were sequentially sequenced in all patients. For those who were negative in the initial screening, we examined ERN1, CHGA, CHGB and NKX6-1 genes and, in selected probands, CACNA1C, GCK, FOXP3, NEUROG3 and CDK4. The incidence rate for PNDM/MDI was calculated using a database of Italian patients collected from 1995 to 2009. RESULTS: In group 1 we found mutations in KCNJ11, INS and ABCC8 genes in 23 (50%), 9 (19.5%) and 4 (8.6%) patients respectively, and a single homozygous mutation in GCK (2.1%). In group 2, we identified one incidence of a KCNJ11 mutation. No genetic defects were detected in other loci. The incidence rate of PNDM/MDI in Italy is estimated to be 1:210,287. CONCLUSIONS/INTERPRETATION: Genetic mutations were identified in ~75% of non-consanguineous probands with PNDM/MDI, using sequential screening of KCNJ11, INS and ABCC8 genes in infants diagnosed within the first 6 months of age. This percentage decreased to 12% in those with diabetes diagnosed between 7 and 12 months. Patients belonging to the latter group may either carry mutations in genes different from those commonly found in PNDM/MDI or have developed an early-onset form of autoimmune diabetes.

Serum elements and oxidative status in clinically isolated syndromes: imbalance and predictivity.

BACKGROUND: Metals are suspected of being involved in the pathogenesis of various neurologic diseases. We previously found a complex imbalance in serum chemical elements and oxidative status in patients with clinically definite multiple sclerosis (CDMS). OBJECTIVE: To understand whether this imbalance affects people with clinically isolated syndrome (CIS) and, if so, whether it predicts conversion to CDMS. METHODS: We studied 22 chemical elements and the oxidative status in 49 patients with CIS, 49 patients with CDMS, and 49 healthy donors (HD). Univariate and multivariate approaches were used to identify profiles for each group. A logistic regression analysis was used to identify the predictive potential of baseline data (elements, oxidative status, and MRI findings) for conversion to CDMS over 36 months. RESULTS: Several elements and oxidative status values differed significantly among the 3 groups. Discriminant analysis revealed a major contribution of Ca, Fe, Sn, Zn, serum antioxidant capacity, and serum oxidative status, which resulted in distinct profiles (the prediction of group membership was 96% [cross-validated 92%] for HD, 92% [cross-validated 92%] for CDMS, and 90% [cross-validated 86%] for CIS). A weighted combination of element concentrations and oxidative status values, adjusting for all other predictors, would predict a reduction in the risk of conversion to CDMS within 3 years (odds ratio 0.37; 95% confidence interval 0.18-0.76; p = 0.007), thereby proving more effective than MRI at baseline. CONCLUSIONS: The peculiar imbalance in serum elements and oxidative status that characterizes patients with CIS and may predict conversion to CDMS warrants studies on larger sample sizes.

Serum transforming growth factor ß1 during diabetes development in non-obese diabetic mice and humans.

Recent data show that regulatory cells with transforming growth factor (TGF)-ß1-dependent activity are able to restore self-tolerance in overtly diabetic non-obese diabetic (NOD) mice. Thus, TGF-ß1 seems to have a relevant role in protection from autoimmune diabetes. Our aim was to investigate the possible significance of serum TGF-ß1 measurement in the natural history of diabetes in NOD mice, as well as in children positive for at least one islet-related antibody. Serum TGF-ß1 (both total and active) was measured by enzyme-linked immunosorbent assay at monthly intervals in 26 NOD mice during the spontaneous development of diabetes and, on a yearly basis, in nine siblings of patients with type 1 diabetes (T1D) with a follow-up of 4 years. Diabetes appeared between the 12th week of age and the end of the study period (36 weeks) in 17 mice. TGF-ß1 serum level variations occurred in the prediabetic period in both NOD mice and humans and diabetes diagnosis followed a continuing reduction of active TGF-ß1 (aTGF-ß1) serum levels. In mice, aTGF-ß1 serum levels measured at 4 weeks of age correlated positively with severity of insulitis, and negatively with percentage of insulin-positive cells. Our findings suggest that in NOD mice serum TGF-ß1 levels during the natural history of the diabetes reflect the course of islet inflammation. The measurement of aTGF-ß1 in islet-related antibody-positive subjects may provide insights into the natural history of prediabetic phase of T1D.

Risk factors for Sjögren's syndrome: a case-control study.

OBJECTIVE: The aim of this study was to investigate potential risk factors for Sjögren's syndrome (SS) by means of a multi-centre case-control study, focusing in particular on familial and environmental risk factors. 140 female SS patients and 109 female controls with orthopaedic problems were consecutively enrolled in seven university hospitals in Italy. METHODS: Information regarding the patient's lifestyle, her medical, menstrual and pregnancy history, and any family history of autoimmune diseases (AD) was obtained through a detailed structured questionnaire. The odds ratio (OR) and 95% confidence interval (95%CI) were calculated using unconditional logistic regression, adjusting for age and family size. The probability of first-degree relatives developing an autoimmune disease was also investigated. RESULTS: A positive family history of AD was significantly associated with SS. Subjects with a first-degree relative (FDR) with AD showed a seven-fold increase in the risk for SS compared to controls (OR=7.4, 95%CI 2.8-20.1); the strength of this association increased with the number of relatives affected. Similarly, the FDR of SS patients had a higher risk of AD in comparison to subjects without FDR affected by SS. Women with one or more pregnancies had an increased risk of SS (OR=2.1, 95%CI 1.0-4.3). CONCLUSION: This study suggests that a family history of AD is associated with SS.

Concordance, disease progression, and heritability of coeliac disease in Italian twins.

BACKGROUND AND AIMS: We adopted the twin method to disentangle the genetic and environmental components of susceptibility to coeliac disease (CD). We estimated disease concordance rate by zygosity and HLA genotypes, discordance times, progression rates to disease, and heritability. METHODS: We crosslinked the Italian Twin Registry with the membership lists of the Italian Coeliac Disease Association and recruited 23 monozygotic (MZ) and 50 dizygotic (DZ) twin pairs with at least one affected member. Zygosity was assigned by DNA fingerprinting, and HLA-DQ and DR alleles were genotyped. Disease status was ascertained by antiendomysial, anti-human tissue transglutaminase antibodies, and bowel biopsy. RESULTS: Concordance was significantly higher in MZ (83.3% probandwise, 71.4% pairwise) than in DZ (16.7% probandwise, 9.1% pairwise) pairs. Concordance was not affected by sex or HLA genotype of the co-twin and being MZ was significantly associated with the occurrence of CD (Cox adjusted hazard ratio 14.3 (95% confidence interval 4.0-50.3)). In 90% of concordant pairs the discordance time was

Familial autoimmunity as a risk factor for systemic lupus erythematosus and vice versa: a case-control study.

The objective of this multicentric case-control study was to investigate if a history of autoimmune disease (AD) in first-degree relatives (FDR) is a risk factor for systemic lupus erythematosus (SLE) and to evaluate the risk of AD among FDR of SLE patients. Cases were Italian SLE patients consecutively enrolled. Controls were orthopaedic inpatients without any autoimmune diseases. The strength of the association between family history of AD and SLE was measured as an odds ratio (OR) calculated from the coefficient of an unconditional regression model. To calculate the risk of AD among FDR of SLE patients, the extended generalized estimating equation technique was used. In total, 154 SLE cases and 140 controls were enrolled. A family history of AD was reported by 22.7% of SLE patients and by 5.7% of the controls. The risk of SLE increased with the number of FDR with AD (one FDR affected, OR = 4.1; two or more, OR = 11.3). The probability of having AD was higher among FDR of SLE cases in comparison to FDR of controls (RR = 4.6; 95%CI 1.9-11.1). A female SLE patient conferred an increased risk of AD to her FDR; this risk is doubled in females (OR 10.3; 95% CI 3.1-34.4).

Postpartum thyroiditis is associated with fluctuations in transforming growth factor-beta1 serum levels.

Postpartum thyroiditis (PPT) is characterized by a rapid evolution and recovery of euthyroidism. Therefore, it can represent a good model to study early cytokine fluctuations in autoimmune thyroid diseases. TGFbeta1 is an immunosuppressive cytokine, as it inhibits T and B cell proliferation, natural killer cell cytotoxic activity, and the generation of T cell cytotoxicity. The aim of this study was to assess serum concentrations of TGFbeta1 during pregnancy and to study possible serum fluctuations of this cytokine during the different phases of PPT. Thyroid biochemical pattern, antithyroid autoantibodies (ATA), and total and active TGFbeta1 (aTGFbeta1) serum concentrations were evaluated in 63 pregnant women. Thirty-four of them were ATA(+), and 29 were ATA(-). Twenty of the 34 ATA(+) women were followed in the postpartum year. Nine of these 20 women developed PPT; 11 remained euthyroid. All of the PPT women became euthyroid during the follow-up. Our results showed 1) detectable serum levels of aTGFbeta1 in 50% of ATA(+) pregnant women, suggesting that the presence of autoantibodies may characterize a favorable condition for TGFbeta1 activation; and 2) decreased total TGFbeta1 and increased aTGFbeta1 serum levels during the active phase of PPT in ATA(+) women. This seems to suggest that inflammation may be responsible for TGFbeta1 activation and autoantibody increase because of antigen release. Although further studies of women with persistent hypothyroidism after the postpartum year are needed, the possibility that the enhanced activation of TGFbeta1 may contribute to resolution of thyroid inflammation postpartum cannot be excluded.

[Regression methods and causal inference: structural equations models]. / Metodi di regressione e inferenza causale: i modelli di equazioni strutturali.

The estimate of correlations among observed outcomes is crucial in biomedical research, especially when the aim of the study is to infer, from the magnitude of these correlations, the causal influence of certain, sometimes latent, factors. In such situations, a typical regression approach, known as "structural equation models" (SEM), which was introduced in the 1970s, becomes significant. These models allow hypotheses to be formulated quite clearly, thanks to some explicit and rigorous graphical representations, on which the "path analysis" is based. SEM, which were initially used in economics, have in the past decade been applied in a wide variety of fields, especially in genetic epidemiology. It's in this field that SEM are extraordinarily effective, representing a simple yet powerful means of estimating the contribution of genes and the environment to the phenotypic expression of a given disease. To this end, data on twins are particularly useful, and in this case the correlation between the outcomes describes the extent of similarity of the twin phenotypes. From this standpoint, SEM undoubtedly constitute one of the most promising statistical tools for family studies and quantitative genetic research. The method can be easily extended to traditional epidemiology, and some interesting applications have already been developed in occupational and social epidemiology. In this paper, we describe in detail the SEM approach and discuss the use of these models in genetic epidemiology, using twin studies as an example. We also discuss the application of SEM in fields other than genetic research.

Permanent diabetes mellitus in the first year of life.

AIMS/HYPOTHESIS: The pathogenesis of permanent diabetes mellitus diagnosed early in life is heterogeneous and, in most cases, not known. We aimed at identifying markers differentiating between non-autoimmune and autoimmune diabetes. METHODS: The clinical, genetic and epidemiological features of 111 diabetic patients (62 males) who received insulin within 12 months of life were studied. RESULTS: The epidemic curve by age of diabetes onset revealed two subsets of patients at a cutoff of 180 days. In the group with diabetes onset before 180 days ("early onset" permanent diabetes) the analysis of HLA susceptibility heterodimers (available for 21 individuals) showed that 76% had a "protective" HLA genotype for Type I (insulin-dependent) diabetes mellitus as compared to 11.9% (5/42) of the later onset group. Accordingly, "early onset" children were less likely to have autoimmunity markers (4 out of 26 tested) than children with onset after 180 days (13 out 20 tested) (15.4% vs. 65.0%, p<0.01). Of note, 19 out of 20 (or the 95%) patients who were born on the island of Sardinia, an Italian region where the incidence of Type I diabetes is six times higher than continental Italy (33/100,000/year vs 5/100,000/year), were included in the later onset group (>180 days). Small-for-date birthweight, a possible sign of reduced foetal insulin secretion, was more common in the "early onset" group (OR=9.9, 95%-CI 2.6-38.6). CONCLUSION/INTERPRETATION: These results, obtained in the largest population-based cohort of diabetic infants hitherto reported, suggest that "early onset" permanent diabetes cases differ from later onset cases and that most of them do not have an autoimmune pathogenesis.

The first large population based twin study of coeliac disease.

BACKGROUND AND AIMS: The genetic load in coeliac disease has hitherto been inferred from case series or anecdotally referred twin pairs. We have evaluated the genetic component in coeliac disease by estimating the concordance rate for the disease among twin pairs in a large population based study. METHODS: The Italian Twin Registry was matched with the membership lists of a patient support group. Forty seven twin pairs were recruited and screened for antiendomysial (EMA) and antihuman-tissue transglutaminase (anti-tTG) antibodies; zygosity was verified by DNA fingerprinting and twins were typed for HLA class II DRB1 and DQB1 molecules. RESULTS: Concordance rates for coeliac disease differ significantly between monozygotic (MZ) (0.86 probandwise and 0.75 pairwise) and dizygotic (DZ) (0.20 probandwise and 0.11 pairwise) twins. This is the highest concordance so far reported for a multifactorial disease. A logistic regression model, adjusted for age, sex, number of shared HLA haplotypes, and zygosity, showed that genotypes DQA1*0501/DQB1*0201 and DQA1*0301/DQB1*0302 (encoding for heterodimers DQ2 and DQ8, respectively) conferred to the non-index twin a risk of contracting the disease of 3.3 and 1.4, respectively. The risk of being concordant for coeliac disease estimated for the non-index twin of MZ pairs was 17 (95% confidence interval 2.1-134), independent of the DQ at risk genotype. CONCLUSION: This study provides substantial evidence for a very strong genetic component in coeliac disease, which is only partially due to the HLA region.

A population-based study on the frequency of additional congenital malformations in infants with congenital hypothyroidism: data from the Italian Registry for Congenital Hypothyroidism (1991-1998).

In the last decade a high frequency of other congenital anomalies has been reported in infants with congenital hypothyroidism (CH) detected by neonatal screening. In the present study the occurrence of additional congenital malformations (CM) in the population of CH infants detected in Italy between 1991 and 1998 (n = 1420) was investigated. In Italy all of the centers in charge of screening, treatment, and follow-up of CH adhere to the Italian National Registry of infants with CH. In this study a high prevalence of additional CM (8.4%), more than 4-fold higher than that reported in the Italian population (1-2%), was found in the population of CH infants. Cardiac anomalies represented the most frequent malformations associated with CH, with a prevalence of 5.5%. However, a significant association between CH and anomalies of nervous system, eyes, and multiple CM was also observed. In conclusion, the significantly higher frequency of extrathyroidal congenital malformations reported in the CH infants than in the general population represents a further argument supporting the role of a genetic component in the etiology of CH. Investigations of the molecular mechanisms underlying developmental events of formation of thyroid and other organs represent critical steps in the knowledge of CH etiology.

Mutations in the HFE gene and their interaction with exogenous risk factors in hepatocellular carcinoma.

The possible role of iron in facilitating the development of liver cancer is still debated. The aims of this study were to define the prevalence of the mutations 845G --> A and 187C --> G (C282Y and H63D) in the HFE gene associated with hereditary hemochromatosis in Italian patients with hepatocellular carcinoma occurring in cirrhosis and to analyze the interaction between these mutations and other established risk factors for hepatocellular carcinoma. The HFE gene mutations, performed by polymerase chain reaction, were analyzed in 81 patients (63 males, 18 females) with hepatocellular carcinoma. None of the patients had a phenotype compatible with homozygous hereditary hemochromatosis. Interaction between HFE mutations and exogenous risk factors was analyzed by collecting information on alcohol consumption, hepatitis B and C virus infections, and iron status at the time of diagnosis of chronic liver disease. This analysis was performed only in males to rule out gender influence on patients' iron status by using the case-only approach specifically designed to estimate departure from multiplicative risk ratios under the assumption of independence between genotype and environmental exposure. The prevalence of the C282Y mutation was significantly higher in patients with hepatocellular carcinoma than in normal controls (8.6% vs 1.6%, P < 0.03). At univariate analysis, iron overload was significantly associated with both HFE mutations (P < 0.0001), whereas ongoing hepatitis B virus infection was associated with the C282Y mutation (P < 0.05). By multivariate analysis, a trend for an increased risk of being positive for hepatitis virus markers (OR 2.9, CI 95% 0.9-9.5) and of having been alcohol abusers (OR 3, CI 95% 0.7-14) was observed in patients heterozygous for the HFE mutations. These data indicate that the prevalence of the main mutation associated with hereditary hemochromatosis is significantly higher in cirrhotic Italian patients with hepatocellular carcinoma compared to a normal population and suggest that heterozygotes for HFE mutations exposed to hepatitis virus infections or who had been alcohol abusers could have an increased risk of developing cirrhosis and later liver cancer than people without the mutations exposed to the same risk factors.

Rate of incidence of hepatocellular carcinoma in patients with compensated viral cirrhosis.

BACKGROUND: Cirrhosis of viral etiology due to hepatitis B virus (HBV) or hepatitis C virus (HCV) infection is a risk factor for hepatocellular carcinoma (HCC). The current study evaluated the rate of incidence of HCC in patients with compensated cirrhosis of viral etiology. METHODS: Two hundred fifty-nine cirrhotic patients (66 hepatitis B surface antigen [HBsAg] positive, 166 HCV positive, and 27 HBsAg/HCV positive) were longitudinally examined every 6 months by serum alpha-fetoprotein test and liver ultrasonography. The rates of incidence of HCC were calculated by the person-years method. The Kaplan-Meier method was used to estimate the cumulative probability of HCC development. Differences in survival time were evaluated by a log rank test. Independent predictors of HCC development were estimated by Cox proportional hazard regression analysis. RESULTS: During a mean follow-up of 64.5 months, HCC developed in 51 (19.7%) patients: in 34 of 166 HCV positive subjects (20.5%) (mean follow-up, 66.3 months), in 6 of 66 of those HBsAg positive (9.1%) (mean follow-up, 55.06 months), and in 11 of 27 of those with dual HBsAg/HCV infection (40.7%) (mean follow-up, 76.4 months). The rate of incidence of HCC per 100 person-years of follow-up was 3.7 in HCV positive subjects, 2.0 in those HBsAg positive, and 6.4 in those with dual infection. Cumulative HCC appearance rates in HBsAg positive, HCV positive, and HBsAg/HCV positive subgroups were 10%, 21%, and 23% at 5 years, 16%, 28%, and 45% at 10 years, and 16%, 40%, and 55% at 13 years, respectively. Multivariate analysis indicated that age >50 years (hazard risk [HR], 4.5; 95% confidence interval [CI] = 2.1-9.4), male gender (HR, 2.8; 95% CI = 1.1-5.3), and HBsAg/HCV coinfection (HR, 2.3; 95% CI = 1.1-4.6) were independent predictors of HCC development. CONCLUSIONS: These findings confirm that male gender and more advanced age (>50 years) are risk factors for HCC in patients with cirrhosis. Furthermore, the data indicate that subjects with dual HBsAg/HCV infection are at highest risk for HCC. Surveillance programs for early detection of HCC should focus especially on these patients.