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Dive into the research topics where Kristian Bjøro is active.

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Featured researches published by Kristian Bjøro.


The New England Journal of Medicine | 1994

Hepatitis C Infection in Patients with Primary Hypogammaglobulinemia after Treatment with Contaminated Immune Globulin

Kristian Bjøro; Stig S. Frøland; Zhibing Yun; Samdal Hh; Terese Haaland

BACKGROUND In Scandinavia many patients with primary hypogammaglobulinemia contracted non-A, non-B hepatitis after intravenous treatment with an immune globulin product that was later found to contain a non-A, non-B hepatitis virus. METHODS We studied the prevalence and clinical course of hepatitis C virus (HCV) infection in a group of 55 Norwegian patients with primary hypogammaglobulinemia and investigated its association with the use of contaminated immune globulin. We used the polymerase chain reaction to detect HCV RNA and performed HCV genotyping. We also analyzed the responses to treatment with interferon. RESULTS Of 20 patients who received the contaminated immune globulin, 17 were seropositive for HCV RNA: In addition, 1 of 35 patients not exposed to the contaminated immune globulin was HCV RNA--positive. HCV genotype V was found in all 12 patients for whom genotyping was performed, but 8 patients also had genotype II or III, or both. All HCV RNA--positive patients had abnormal results on biochemical liver tests. All liver-biopsy specimens (from 15 patients) were abnormal, with portal inflammation, bile-duct damage, and focal necrosis. In six patients there was cirrhosis. Two patients died of liver failure. In 4 of the 10 patients treated with interferon there were complete, though transient, biochemical responses, but the follow-up biopsy specimens showed evidence of histologic progression. The poorest responses to interferon were among the patients with multiple HCV genotypes. All but one patient remained positive for HCV RNA: CONCLUSIONS In patients with primary hypogammaglobulinemia there was a high rate of HCV infection after treatment with contaminated immune globulin. In these immunocompromised patients HCV infection has a severe and rapidly progressive course, and responses to interferon are poor.


Hepatology | 2004

Treatment with pegylated interferon and ribavarin in HCV infection with genotype 2 or 3 for 14 weeks: A pilot study

Olav Dalgard; Kristian Bjøro; Kjell Block Hellum; Bjørn Myrvang; Ståle Ritland; Kjell Skaug; N. Raknerud; Helge Bell

The aim of this study was to determine the efficacy of 14 weeks of treatment in patients infected with hepatitis C virus (HCV) genotype 2 or 3 who achieve early virological response (EVR). In a noncontrolled multicenter trial, 122 treatment‐naive patients received 1.5 μg/kg pegylated interferon alfa‐2b subcutaneously once weekly and 800 to 1,400 mg/d ribavirin based on body weight. Treatment was stopped at week 14 in patients with EVR, defined as undetectable HCV RNA at weeks 4 and 8. Patients without EVR were assigned to 24 weeks of treatment. The primary end point was sustained virological response (SVR), defined as undetectable HCV RNA 24 weeks after end of treatment. Among the 122 patients, 95 (78%) had EVR and received 14 weeks of treatment. The remaining 27 (22%) were treated for 24 weeks. SVR was obtained in 85 (90%) of 95 patients in the 14‐week treatment group and 15 of (56%) 27 in the 24‐week treatment group. Altogether, SVR was obtained in 100 of 122 patients (82%; 95% CI, 75%‐89%). SVR after 14 weeks of treatment was achieved more frequently among genotype 3a patients with low viral load compared with high viral load (98% vs. 79%; P = .019). Logistic regression analysis showed that absence of bridging fibrosis/cirrhosis was the only independent predictor of SVR. In conclusion, patients with genotype 2 or 3 and EVR obtained a high SVR after 14 weeks of treatment. The results need to be confirmed in a randomized, controlled study before this treatment approach can be recommended, particularly for patients with genotype 3 and high viral load or severe fibrosis. (HEPATOLOGY 2004;40: 1260–1265.)


Hepatology | 2007

Pegylated interferon alfa and ribavirin for 14 versus 24 weeks in patients with hepatitis C virus genotype 2 or 3 and rapid virological response

Olav Dalgard; Kristian Bjøro; Helmer Ring-Larsen; Einar Björnsson; Mona Holberg-Petersen; Eva Skovlund; Olle Reichard; Bjørn Myrvang; Bo Sundelöf; Ståle Ritland; Kjell Block Hellum; Aril Frydén; Jon Florholmen; Hans Verbaan

A recent nonrandomized pilot trial showed that hepatitis C virus (HCV) patients with genotype 2/3 and rapid virological response (RVR) had a 90% sustained virological response (SVR) rate after 14 weeks of treatment. We aimed to assess this concept in a randomized controlled trial. In the trial, 428 treatment‐naïve HCV RNA–positive patients with genotype 2 or 3 were enrolled. Patients with RVR were randomized to 14 (group A) or 24 (group B) weeks of treatment. Patients were treated with pegylated interferon α‐2b (1.5 μg/kg) subcutaneously weekly and ribavirin (800‐1400 mg) orally daily. The noninferiority margin was set to be 10% between the two groups with a one‐sided 2.5% significance level. RVR was obtained in 302 of 428 (71%), and 298 of these were randomized to group A (n = 148) or group B (n = 150). In the intention‐to‐treat analysis, SVR rates were 120 of 148 (81.1%) in group A and 136 of 150 (90.7%) in group B (difference, 9.6%; 95% confidence interval, 1.7‐17.7). Among patients with an HCV RNA test 24 weeks after the end of treatment, 120 of 139 (86.3%) patients in group A achieved SVR compared with 136 of 146 (93.2%) in group B (difference, 6.9%; 95% confidence interval, −0.1 to +13.9). Conclusion: We cannot formally claim that 14 weeks of treatment is noninferior to 24 weeks of treatment. However, the SVR rate after 14 weeks of treatment is high, and although longer treatment may give slightly better SVR, we believe economical savings and fewer side effects make it rational to treat patients with genotype 2 or 3 and RVR for only 14 weeks. (HEPATOLOGY 2007.)


Scandinavian Journal of Gastroenterology | 2009

Metformin in patients with non-alcoholic fatty liver disease: A randomized, controlled trial

John Willy Haukeland; Zbigniew Konopski; Heidi B. Eggesbø; Hilde Løland von Volkmann; Gabriele Raschpichler; Kristian Bjøro; Terese Haaland; Else Marit Løberg; Kåre I. Birkeland

Objective. The antidiabetic agent metformin is regularly discussed as a promising treatment for non-alcoholic fatty liver disease (NAFLD), which is characterized by insulin resistance. However, the evidence for its beneficial effects is limited, and conflicting reports have been published. The purpose of this study was to conduct a randomized, double-blind, placebo-controlled trial to test whether metformin improves liver histology in patients with non-alcoholic fatty liver disease. Material and methods. Forty-eight patients with biopsy-proven NAFLD were randomized to treatment with metformin (n=24) or placebo (n=24) for 6 months. A second liver biopsy was obtained in all subjects who completed the trial (n=44). Data analyses are restricted to this group (per-protocol analyses). The primary outcome was changes in histologically assessed liver steatosis. Secondary outcomes were changes in NAFLD activity (NAS)-score, liver steatosis assessed by computed tomography (CT), liver transaminases, body-weight, metabolic variables and inflammatory markers. Results. No significant differences between treatment with metformin or placebo were observed for changes in liver steatosis, assessed either histologically or by CT, NAS-score, liver transaminases or on markers of insulin resistance or inflammation. In contrast, beneficial effects of metformin were observed on changes in body-weight (p<0.001), serum levels of cholesterol (p=0.004), LDL-cholesterol (p<0.001), glucose (p=0.032) and on HbA1c (p=0.020). Conclusions. Treatment with metformin for 6 months was no better than placebo in terms of improvement in liver histology in patients with NAFLD. Nevertheless, the use of metformin could still be beneficial in this group as it is associated with a reduction in serum levels of lipids and glucose. (ClinicalTrials.gov number, NCT00303537)


European Addiction Research | 2002

Treatment of Chronic Hepatitis C in Injecting Drug Users: 5 Years’ Follow-Up

Olav Dalgard; Kristian Bjøro; Kjell Block Hellum; Bjørn Myrvang; Kjell Skaug; B. Gutigard; H. Bell

Aim of the Study: To assess the long-term hepatitis C (HCV) treatment outcome in former injecting drug users (IDUs). Materials and Methods: A long-term follow-up of 27 former IDUs who had been successfully treated for chronic hepatitis C was performed. These patients represented all IDUs who had obtained a sustained virological response in a Norwegian HCV treatment trial. The patients had been treated with interferon-α alone or in combination with ribavirin. At 5 years’ follow-up the 27 IDUs were retested for HCV RNA and risk behaviour for HCV transmission after treatment was assessed. In the control group all 18 non-IDUs who had obtained a sustained virological response in the same treatment trial were included. Results: At follow-up 13–82 months (median 64) after the end of treatment only one case of probable reinfection was seen among the 27 IUDs. No reoccurrence of HCV was observed in the control group. The IDU who was HCV RNA positive at follow-up had continued injecting drugs and reported frequent needle sharing. At follow-up HCV of genotype 1a was detected in contrast to genotype 1b before treatment indicating that this patient was reinfected with HCV. A return to injecting drug use occurred in 9 (33%) of 27 IDUs. Conclusion: The long-term outcome of HCV treatment in former IDUs was excellent. Despite frequent reinitiation of drug injection all but 1 remained HCV RNA negative.


Hepatology | 2011

IL28B genetic variation and treatment response in patients with hepatitis C virus genotype 3 infection

Amir Moghaddam; Espen Melum; Nils Reinton; Helmer Ring-Larsen; Hans Verbaan; Kristian Bjøro; Olav Dalgard

Polymorphisms near the IL28B gene, which code for interferon (IFN)‐λ3, predict response to pegylated interferon‐α (PEG‐IFN) and ribavirin treatment in hepatitis C virus (HCV) genotype 1 infected patients. Follow‐up studies of the effect of IL28B gene in HCV non–genotype 1 infected patients have almost always used predominantly HCV genotype 2–infected or mixed genotype 2/3–infected cohorts with results partly conflicting with HCV genotype 1. We performed a retrospective analysis of 281 patients infected with HCV genotype 3 for association of response to therapy with IL28B polymorphisms. We found that the HCV genotype 1 responder genotypes at rs12979860 and rs8099917 did not associate with sustained virological response to PEG‐IFN/ribavirin therapy. However, the responder genotypes of both SNPs showed association with rapid viral response measured at 4 weeks (rs12979860, P = 3 × 10−5; rs8099917, P = 3 × 10−4). In multivariate analysis, age (<40 years), baseline viral load (<4 × 105 IU/mL) and the responder genotypes of SNPs rs12979860 or rs8099917 remained significant independent predictors of rapid viral response to therapy. Furthermore, we show that IL28B polymorphisms are associated with relapse in patients who achieve rapid viral response to PEG‐IFN/ribavirin therapy. The responder genotypes also showed association with markers of stage and activity of liver disease, namely high aspartate aminotransferase platelet ratio index (APRI, rs12979860, P = 0.018; rs8099917, not significant) and high alanine aminotransferase (ALT, rs12979860, P = 0.002; rs8099917, P = 0.001), in addition to a high baseline viral load (rs12979860, P = 1.4 × 10−5; rs8099917, P = 7.3 × 10−6). Conclusion: Polymorphisms near the IL28B gene show association with rapid viral response but not sustained viral response to PEG‐IFN/ribavirin therapy in HCV genotype 3‐infected patients. (HEPATOLOGY 2011;)


Liver Transplantation | 2005

Recurrent primary sclerosing cholangitis after liver transplantation: A magnetic resonance cholangiography study with analyses of predictive factors

Bjørn Brandsæter; Erik Schrumpf; Øystein Bentdal; Kurt Brabrand; Hans-Jørgen Smith; Andreas Abildgaard; O. P. F. Clausen; Kristian Bjøro

Primary sclerosing cholangitis (PSC) is a well‐established indication for orthotopic liver transplantation (OLT), but post‐OLT bile duct strictures complicate the outcome for these patients. These strictures might represent recurrent PSC (rPSC). To estimate the risk factors for post‐OLT non‐anastomotic bile duct strictures in PSC patients and to find their possible etiology, we performed magnetic resonance cholangiography (MRC) and angiography (MRA) in all PSC patients who had undergone OLT and were alive (median follow‐up 6.4 years, range 1.4‐15.2 years). This group of PSC patients was compared to a group of 45 non‐PSC patients who had also undergone OLT. A logistic regression analysis was performed to find predictors of rPSC. Bile duct strictures were found in 19/49 PSC patients and in 4/45 non‐PSC patients (P = 0.001). In the PSC group nine patients without other possible explanations for bile duct strictures than rPSC were identified, i.e., the estimated risk of rPSC was 9/49 (18%); surprisingly similar changes were also seen in one patient without a pre‐transplant PSC diagnosis. Severe liver disease due to rPSC was seen in 4/9 patients (one patient died and three are being evaluated for re‐OLT). Steroid‐resistant rejection was the only significant predictor for rPSC. In conclusion, our study shows that by the use of MRC we found more bile duct strictures in PSC patients post‐OLT compared to controls and that steroid‐resistant rejections was a predictor of such changes. (Liver Transpl 2005.)


Scandinavian Journal of Gastroenterology | 2005

Abnormal glucose tolerance is a predictor of steatohepatitis and fibrosis in patients with non-alcoholic fatty liver disease.

John Willy Haukeland; Zbigniew Konopski; Paul Linnestad; Shafiullah Azimy; Else Marit Løberg; Terese Haaland; Kåre I. Birkeland; Kristian Bjøro

Objective. The majority of patients with non-alcoholic fatty liver disease (NAFLD) have simple steatosis. A minority, however, present with non-alcoholic steatohepatitis (NASH), a condition that can lead to advanced fibrosis and cirrhosis. The frequencies of NASH and fibrosis among patients with NAFLD and sustained elevation of liver function tests (LFT) are uncertain. Our aim was to estimate these frequencies. We characterize a population with NAFLD, with special emphasis on insulin resistance and the metabolic syndrome, and study possible predictors for different stages of the disease. Material and methods. All referred patients with sustained elevation of LFT, radiological evidence or clinical suspicion of fatty liver, and absence of other liver disease, were invited to participate in our study in the period June 2002 to December 2004. Results. Of 129 patients who met the inclusion criteria, 88 underwent liver biopsy. NAFLD was verified in 83 of them. Among these patients, 59 (71%) had the metabolic syndrome, 41 (49%) had NASH and 36 (43%) had fibrosis. Abnormal glucose tolerance (T2DM or impaired glucose tolerance) was the only independent risk factor for NASH (OR: 3.14; 95% CI: 1.20–8.23). Independent predictors for fibrosis were abnormal glucose tolerance (OR: 3.83; 95% CI: 1.29–11.40) and body mass index (OR: 1.20; 95% CI: 1.06–1.36) per kg/m2. Conclusions. Both NASH and fibrosis are frequently present among patients with NAFLD and sustained elevation of LFT. The probability of these potentially progressive stages of NAFLD increases with the presence of abnormal glucose tolerance.


Scandinavian Journal of Gastroenterology | 2002

Effect of Combined Interferon-α Induction Therapy and Ribavirin on Chronic Hepatitis C Virus Infection: a Randomized Multicentre Study

Kristian Bjøro; H Bell; K Hellum; Kjell Skaug; N. Raknerud; P. Sandvei; B. Døskeland; A Maeland; S. Lund-Tønnesen; B Myrvang

Background: The efficacy of interferon- α (IFN) induction in combination with ribavirin for chronic hepatitis C virus (HCV) infection is not known. Methods: A total of 256 treatment-naive HCV RNA-positive patients with biopsy-confirmed chronic hepatitis were enrolled in a randomized multicentre study. The patients received either standard combination therapy with 3 MIU interferon- α 2b thrice weekly for 26 weeks or 6 MIU interferon- α 2b daily for 4 weeks and 3 MIU 3/7 days for 22 weeks. All patients received ribavirin 1000 mg or 1200 mg (weight dependent) daily during the 26-week treatment period. Patients were monitored for HCV RNA during and following treatment. Results: The sustained virological response rates (26 weeks after end of treatment) were 54% and 47% for patients receiving IFN induction/ribavirin and standard IFN/ribavirin, respectively ( P = 0.35). Among patients infected with genotype 1a/1b, the sustained response rates were 32% and 35%. In patients infected with genotype 2b/3a IFN induction/ribavirin led to a sustained response rate of 80% as compared to 65% in the standard combination therapy group ( P = 0.073). Steatosis was more frequently seen in liver biopsies from patients infected with genotype 3a as compared to genotypes 1a/1b. Among genotype 1a/1b infected patients, steatosis was a highly significant predictor of failure to achieve sustained virological response. Logistic regression analysis (multivariate analysis) showed that independent predictors of sustained virological response were low age, female gender, genotype 2b/3a and HCV RNA negativity at 2 weeks. Conclusions: IFN induction in combination with ribavirin does not increase the sustained virological response rate among patients infected with HCV. Absence of steatosis is an independent predictor of sustained virological response in patients infected with genotypes 1a/1b.


The Journal of Clinical Endocrinology and Metabolism | 2010

Intracellular Nicotinamide Phosphoribosyltransferase Protects against Hepatocyte Apoptosis and Is Down-Regulated in Nonalcoholic Fatty Liver Disease

Tuva B. Dahl; John Willy Haukeland; Arne Yndestad; Trine Ranheim; Ivar P. Gladhaug; Jan Kristian Damås; Terese Haaland; Else Marit Løberg; Borghild Arntsen; Kåre I. Birkeland; Kristian Bjøro; Stine M. Ulven; Zbigniew Konopski; Hilde I. Nebb; Pål Aukrust; Bente Halvorsen

CONTEXT Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in Western and non-Western countries, but its pathogenesis is not fully understood. OBJECTIVE Based on the role of nicotinamide phosphoribosyltransferase (NAMPT) in fat and glucose metabolism and cell survival, we hypothesized a role for NAMPT/visfatin in the pathogenesis of NAFLD-related disease. DESIGN AND SETTING We conducted clinical studies at a referral medical center in well-characterized NAFLD patients (n = 58) and healthy controls (n = 27). In addition we performed experimental in vitro studies in hepatocytes. MAIN OUTCOME MEASURES We examined 1) the hepatic and systemic expression of NAMPT/visfatin in patients with NAFLD and control subjects, 2) the hepatic regulation of NAMPT/visfatin, and 3) the effect of NAMPT/visfatin on hepatocyte apoptosis. RESULTS Our main findings were as follows. 1) Patients with NAFLD had decreased NAMPT/visfatin expression both systemically in serum and within the hepatic tissue, with no difference between simple steatosis and nonalcoholic steatohepatitis. 2) By studying the hepatic regulation of NAMPT/visfatin in wild-type and peroxisome proliferators-activated receptor (PPAR)alpha(-/-) mice as well as in hepatocytes, we showed that PPARalpha activation and glucose may be involved in the down-regulation of hepatic NAMPT/visfatin expression in NAFLD. 4) Within the liver, NAMPT/visfatin was located to hepatocytes, and our in vitro studies showed that NAMPT/visfatin exerts antiapoptotic effects in these cells, involving enzymatic synthesis of nicotinamide adenine dinucleotide. CONCLUSION Based on these findings, we suggest a role for decreased NAMPT/visfatin levels in hepatocyte apoptosis in NAFLD-related disease.

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Dive into the Kristian Bjøro's collaboration.

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Olav Dalgard

Akershus University Hospital

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Erik Schrumpf

Oslo University Hospital

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Kjell Block Hellum

Akershus University Hospital

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Espen Melum

Oslo University Hospital

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Terese Haaland

Oslo University Hospital

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Kjell Skaug

Norwegian Institute of Public Health

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Michael Olausson

Sahlgrenska University Hospital

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Styrbjörn Friman

Sahlgrenska University Hospital

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