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Dive into the research topics where Jørgen Jahnsen is active.

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Featured researches published by Jørgen Jahnsen.


Scandinavian Journal of Gastroenterology | 2009

Clinical course during the first 10 years of ulcerative colitis: results from a population-based inception cohort (IBSEN Study)

Inger Camilla Solberg; Idar Lygren; Jørgen Jahnsen; Erling Aadland; Ole Høie; Milada Cvancarova; Tomm Bernklev; Magne Henriksen; Jostein Sauar; Morten H. Vatn; Bjørn Moum

Objective. Cohort studies of unselected and newly diagnosed patients are essential for a better understanding of the prognosis in ulcerative colitis (UC). The aim of this study was to evaluate the course of UC in a population-based inception cohort during the first 10 years, and to identify prognostic risk factors based on information gathered at diagnosis. Material and methods. From 1990 to 1994, a population-based cohort of 843 patients with inflammatory bowel disease was enrolled in South-Eastern Norway. The cohort was systematically followed-up at 1, 5 and 10 years after diagnosis. Results. Of 519 patients with UC, 423 completed the 10-year follow-up, 53 died and 43 were lost to follow-up. The mortality risk was not increased compared with that in the general population. The cumulative colectomy rate after 10 years was 9.8% (95% CI: 7.4–12.4%). Initial presentation with extensive colitis and erythrocyte sedimentation rate (ESR) ≥30 mm/h was associated with an increased hazard ratio (HR) (3.57, 95% CI: 1.60–7.96) and age ≥50 years at diagnosis, with reduced HR (0.28, 95% CI: 0.12–0.65) for subsequent colectomy. Relapsing disease was noted in 83%, but half (48%) of the patients were relapse free during the last 5 years. One-fifth (69/288) of patients with proctitis or left-sided colitis had progressed to extensive colitis. Conclusions. The prognosis for UC during the first 10 years was generally good. The colectomy rate was low, and a large proportion of patients were in remission as time progressed. Patients with initially extensive colitis and elevated ESR could benefit from an early potent medical treatment strategy.


Scandinavian Journal of Gastroenterology | 1998

Incidence and Prevalence of Primary Biliary Cirrhosis, Primary Sclerosing Cholangitis, and Autoimmune Hepatitis in a Norwegian Population

K. M. Boberg; E. Aadland; Jørgen Jahnsen; N. Raknerud; M. Stiris; H. Bell

BACKGROUND The relative frequencies of the autoimmune liver diseases primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH) have not been studied. We therefore performed an epidemiologic investigation to describe the incidence and prevalence of the three diseases in a defined population. METHODS Patients with PBC, PSC, or AIH admitted to Aker University Hospital in Oslo were prospectively registered during the 10-year period 1986-95. This hospital serves a defined population of 130,000 inhabitants. The mean yearly incidence and the point prevalences at the end of each year were calculated. RESULTS During the 10-year period 21 patients with PBC, 17 with PSC, and 25 with AIH were diagnosed. The mean annual incidence per 100,000 was 1.6 for PBC, 1.3 for PSC, and 1.9 for AIH. The point prevalences per 100,000 on 31 December 1995 were 14.6, 8.5, and 16.9 for PBC, PSC, and AIH, respectively. CONCLUSIONS The prevalences of PBC and AIH are of the same order of magnitude and about twice as high as that of PSC. These epidemiologic data can be used to estimate the number of liver transplantations required due to autoimmune liver diseases.


Gastroenterology | 1998

Gluten induces an intestinal cytokine response strongly dominated by interferon gamma in patients with celiac disease

Ellen M. Nilsen; Frode L. Jahnsen; Knut E.A. Lundin; Finn-Eirik Johansen; Olav Fausa; Ludvig M. Sollid; Jørgen Jahnsen; Helge Scott; Per Brandtzaeg

BACKGROUND & AIMS Celiac disease appears to be a T cell-mediated enteropathy induced by gluten in genetically predisposed individuals. Duodenal biopsy specimens from patients with celiac disease and histologically normal controls were investigated to see if cytokine expression is related to disease activity. METHODS Cytokine messenger RNA (mRNA) expression was determined by quantitative reverse-transcription polymerase chain reaction and in situ expression by immunohistochemistry. RESULTS In normal controls, mRNA levels were usually below the quantitative limit, even after in vitro gluten stimulation. By contrast, interferon (IFN)-gamma mRNA was increased more than 1000-fold in untreated disease. In vitro gluten stimulation of specimens from treated patients (gluten-free diet) increased IFN-gamma mRNA to the levels of untreated patients. In addition, increased mRNA levels for interleukin (IL)-2, IL-4, IL-6, and tumor necrosis factor alpha were found after such stimulation, whereas mRNA for IL-5, IL-10, and IL-12p40 was usually below the quantitative level. Biopsy specimens from untreated patients contained on average 10-fold more lamina propria cells positive for IFN-gamma than normal controls, whereas cells containing IL-4 were rare in both subject groups. CONCLUSIONS The results show that mucosal gluten exposure in patients with celiac disease rapidly elicits high levels of IFN-gamma expression and lower levels of IL-2, IL-4, IL-6, and tumor necrosis factor alpha even in the virtual absence of IL-12.


The Lancet | 2002

Association of NOD2 (CARD 15) genotype with clinical course of Crohn's disease: a cohort study

Jochen Hampe; Jochen Grebe; Susanna Nikolaus; Camilla Solberg; Peter J. P. Croucher; Silvia Mascheretti; Jørgen Jahnsen; Bjørn Moum; Bodo Klump; Michael Krawczak; Muddassar Mirza; Ulrich R. Foelsch; Morten H. Vatn; Stefan Schreiber

BACKGROUND Crohns disease is a heterogeneous disorder for which NOD2 (CARD 15) has been identified as a susceptibility gene. We investigate the relation between NOD2 genotype and phenotypic characteristics of patients with Crohns disease. METHODS Hypotheses about the relation between NOD2 genotype and Crohns disease phenotype were generated retrospectively from a group of 446 German patients with this disorder. Positive findings (p<0.10) were verified in prospectively established cohorts of 106 German and 55 Norwegian patients with Crohns disease. All patients were genotyped for the main coding mutations in NOD2, denoted SNP8, SNP12, and SNP13, with Taqman technology. FINDINGS In the retrospective cohort, six clinical characteristics showed noteworthy haplotype association: fistulising, ileal, left colonic and right colonic disease, stenosis, and resection. In the German prospective cohort, these haplotype associations could be replicated for ileal (p=0.006) and right colonic disease (p < or =0.001). A similar trend was noted in the Norwegian patients. INTERPRETATION We recorded a distinct relation between NOD2 genotype and phenotype of Crohns disease. Test strategies with NOD2 variations to predict the clinical course of Crohns disease could lead to the development of new therapeutic paradigms.


Digestion | 1997

Assessment of disease activity in ulcerative colitis by faecal calprotectin, a novel granulocyte marker protein.

Arne G. Roseth; Erling Aadland; Jørgen Jahnsen; Nils Raknerud

This study comprised 62 outpatients with ulcerative colitis who underwent 64 colonoscopies. The disease activity was evaluated according to endoscopic and histological criteria. The results revealed a significant correlation between both the endoscopic as well as the histological gradings of disease activity and faecal calprotectin. The median faecal calprotectin levels in the control group (6 mg/l) and in the patients with no or low disease activity (11.5 mg/l) were significantly different (p < 0.0001). The median calprotectin level among patients with active disease was 68 mg/l which was significantly different from the latter group (p < 0.0001). Furthermore, we suggest that the degree of inflammation rather than the extent of the disease determined the faecal calprotectin levels. In conclusion, assessment of faecal calprotectin seems to be a marker of disease activity in patients with ulcerative colitis.


Gut | 1997

Bone mineral density is reduced in patients with Crohn's disease but not in patients with ulcerative colitis: a population based study.

Jørgen Jahnsen; J A Falch; E Aadland; P Mowinckel

BACKGROUND: Patients with inflammatory bowel disease are at risk of developing metabolic bone disease. AIMS: To compare bone mineral density in patients with Crohns disease with patients with ulcerative colitis and healthy subjects, and to evaluate possible risk factors for bone loss in inflammatory bowel disease. PATIENTS: 60 patients with Crohns disease, 60 with ulcerative colitis, and 60 healthy subjects were investigated. Each group consisted of 24 men and 36 women. METHODS: Lumbar spine, femoral neck, and total body bone mineral density were measured by dual x ray absorptiometry (DXA), and Z scores were obtained by comparison with age and sex matched normal values. RESULTS: Mean Z scores were significantly lower in patients with Crohns disease compared with patients with ulcerative colitis and healthy subjects. Patients with ulcerative colitis had bone mineral densities similar to healthy subjects. Use of corticosteroids, body mass index (BMI), and sex were significant predictor variables for bone mineral density in Crohns disease. In ulcerative colitis only body mass index and sex were of significant importance. Disease localisation and small bowel resections had no influence on bone mineral density in patients with Crohns disease. CONCLUSIONS: Patients with Crohns disease have reduced bone mineral density. Several factors are probably involved, but the reduction is associated with corticosteroid therapy. When studying skeletal effects of inflammatory bowel disease, patients with Crohns disease and those with ulcerative colitis should be evaluated separately.


Gut | 2008

C -Reactive Protein: A Predictive Factor And Marker Of Inflammation In Inflammatory Bowel Disease Results From A Prospective Population-Based Study

Magne Henriksen; Jørgen Jahnsen; I Lygren; N. Stray; J Sauar; Morten H. Vatn; Bjørn Moum

Background and aims: C-reactive protein (CRP) levels are often used in the follow-up of patients with inflammatory bowel disease (IBD). The aims of this study were to establish the relationship of CRP levels to disease extent in patients with ulcerative colitis and to phenotype in patients with Crohn’s disease, and to investigate the predictive value of CRP levels for disease outcome. Methods: CRP was measured at diagnosis and after 1 and 5 years in patients diagnosed with IBD in south-eastern Norway. After 5 years, 454 patients with ulcerative colitis and 200 with Crohn’s disease were alive and provided sufficient data for analysis. Results: Patients with Crohn’s disease had a stronger CRP response than did those with ulcerative colitis. In patients with ulcerative colitis, CRP levels at diagnosis increased with increasing extent of disease. No differences in CRP levels at diagnosis were found between subgroups of patients with Crohn’s disease as defined according to the Vienna classification. In patients with ulcerative colitis with extensive colitis, CRP levels above 23 mg/l at diagnosis predicted an increased risk of surgery (odds ratio (OR) 4.8, 95% confidence interval (CI) 1.5 to 15.1, p = 0.02). In patients with ulcerative colitis, CRP levels above 10 mg/l after 1 year predicted an increased risk of surgery during the subsequent 4 years (OR 3.0, 95% CI 1.1 to 7.8, p = 0.02). A significant association between CRP levels at diagnosis and risk of surgery was found in patients with Crohn’s disease and terminal ileitis (L1), and the risk increased when CRP levels were above 53 mg/l in this subgroup (OR 6.0, 95% CI 1.1 to 31.9, p = 0.03). Conclusions: CRP levels at diagnosis were related to the extent of disease in patients with ulcerative colitis. Phenotype had no influence on CRP levels in patients with Crohn’s disease. CRP is a predictor of surgery in subgroups of patients with either ulcerative colitis or Crohn’s disease.


Scandinavian Journal of Gastroenterology | 2002

Vitamin D Status, Parathyroid Hormone and Bone Mineral Density in Patients with Inflammatory Bowel Disease

Jørgen Jahnsen; J. A. Falch; P. Mowinckel; Erling Aadland

Background: Although the pathogenesis of osteoporosis in inflammatory bowel disease (IBD) is not established, vitamin D deficiency and disturbances in calcium metabolism are thought to be of importance, especially in Crohn disease (CD). Vitamin D status is assessed and the relation between indices of calcium metabolism, including 25-hydroxyvitamin D and parathyroid hormone concentrations, and bone mineral density (BMD) in CD and ulcerative colitis (UC) are examined. Sixty patients with CD and 60 with UC were investigated. Each group comprised 24 men and 36 women. Methods: Vitamin D metabolites, parathyroid hormone and biochemical markers of bone metabolism were measured in blood and urine. Lumbar spine, femoral neck and total body BMD were measured by dual X-ray absorptiometry (DXA) and Z-scores were obtained by comparison with age- and sex-matched normal values. Results: Vitamin D deficiency (25-hydroxyvitamin D3 <30 nmol/l) was present in 27% of patients with CD and in 15% with UC. Furthermore, CD patients had a significantly lower mean concentration of 25-hydroxyvitamin D3 compared with UC patients. Vitamin D status was not related to BMD at any of the skeletal sites measured. Secondary hyperparathyroidism was found in 10 out of 27 patients with CD after small-bowel resections. No differences were found in serum osteocalcin and urine pyridinoline between patients with CD and those with UC. Conclusions: Hypovitaminosis D is common in CD patients. Patients with CD and small-bowel resections are at risk of developing secondary hyperparathyroidism and low BMD.


The Lancet | 2017

Switching from originator infliximab to biosimilar CT-P13 compared with maintained treatment with originator infliximab (NOR-SWITCH): a 52-week, randomised, double-blind, non-inferiority trial

Kristin Kaasen Jørgensen; I.C. Olsen; Guro L Goll; Merete Lorentzen; Nils Bolstad; Espen A. Haavardsholm; Knut E.A. Lundin; Cato Mørk; Jørgen Jahnsen; Tore K. Kvien; Ingrid Prytz Berset; Bjørg Ts Fevang; Jon Florholmen; Synøve Kalstad; Nils J Mørk; Kristin Ryggen; Kåre S Tveit; Sigrun K Sæther; Bjørn Gulbrandsen; Jon Hagfors; Kenneth Waksvik; David Warren; Karoline J. Henanger; Øivind Asak; Somyeh Baigh; Ingrid M Blomgren; Trude J Bruun; Katrine Dvergsnes; Svein Oskar Frigstad; Clara G Gjesdal

BACKGROUND TNF inhibitors have improved treatment of Crohns disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, and chronic plaque psoriasis, but are expensive therapies. The aim of NOR-SWITCH was to examine switching from originator infliximab to the less expensive biosimilar CT-P13 regarding efficacy, safety, and immunogenicity. METHODS The study is a randomised, non-inferiority, double-blind, phase 4 trial with 52 weeks of follow-up. Adult patients on stable treatment with infliximab originator treated in a hospital setting for at least 6 months were eligible for participation. Patients with informed consent were randomised in a 1:1 ratio to either continued infliximab originator or to switch to CT-P13 treatment, with unchanged dosing regimen. Data were collected at infusion visits in 40 Norwegian study centres. Patients, assessors, and patient care providers were masked to treatment allocation. The primary endpoint was disease worsening during 52-week follow-up. 394 patients in the primary per-protocol set were needed to show a non-inferiority margin of 15%, assuming 30% disease worsening in each group. This trial is registered with ClinicalTrials.gov, number NCT02148640. FINDINGS Between Oct 24, 2014, and July 8, 2015, 482 patients were enrolled and randomised (241 to infliximab originator, 241 to CT-P13 group; one patient was excluded from the full analysis and safety set for CT-P13) and 408 were included in the per-protocol set (202 in the infliximab originator group and 206 in the CT-P13 group). 155 (32%) patients in the full analysis set had Crohns disease, 93 (19%) had ulcerative colitis, 91 (19%) had spondyloarthritis, 77 (16%) had rheumatoid arthritis, 30 (6%) had psoriatic arthritis, and 35 (7%) had chronic plaque psoriasis. Disease worsening occurred in 53 (26%) patients in the infliximab originator group and 61 (30%) patients in the CT-P13 group (per-protocol set; adjusted treatment difference -4·4%, 95% CI -12·7 to 3·9). The frequency of adverse events was similar between groups (for serious adverse events, 24 [10%] for infliximab originator vs 21 [9%] for CT-P13; for overall adverse events, 168 [70%] vs 164 [68%]; and for adverse events leading to discontinuation, nine [4%] vs eight [3%], respectively). INTERPRETATION The NOR-SWITCH trial showed that switching from infliximab originator to CT-P13 was not inferior to continued treatment with infliximab originator according to a prespecified non-inferiority margin of 15%. The study was not powered to show non-inferiority in individual diseases. FUNDING Norwegian Ministry of Health and Care Services.


Inflammatory Bowel Diseases | 2005

Health-related quality of life in patients with inflammatory bowel disease measured with the short form-36: Psychometric assessments and a comparison with general population norms

Tomm Bernklev; Jørgen Jahnsen; Idar Lygren; Magne Henriksen; Morten H. Vatn; Bjørn Moum

Background: We compared health‐related quality of life (HRQOL) in a population‐based cohort of Norwegian patients with inflammatory bowel disease (IBD) with a normal reference population by means of the short form‐36 (SF‐36) questionnaire, including the effect of age, sex, educational status, and symptom severity and the psychometric properties of the questionnaire. Methods: The SF‐36 was self‐administered and was answered by the patients at the hospital at 2 occasions that were 6 months apart. Results: Five hundred fourteen patients with IBD were eligible for analysis: 348 with ulcerative colitis (UC) and 166 with Crohns disease (CD). The comparison group consisted of 2323 Norwegian people. The dimension scores for SF‐36 were significantly lower in 6 of 8 dimensions for patients with UC and in 7 of 8 dimensions for patients with CD than for the reference population. In both patients with UC and patients with CD, we found lower scores in elderly patients, which also was found in the background population. Women scored lower than men in all dimension scores. In both patients with UC and patients with CD, there was a statistically significant reduction in HRQOL score with increasing symptoms. The SF‐36 has satisfactory reliability and discriminant ability for scores for all dimensions in both patients with UC and patients with CD. However, when measuring responsiveness, the figures were generally low. This finding, together with the high ceiling effects, may indicate that the SF‐36 has limitations regarding detecting deterioration or improvement over time. Conclusion: We have shown that HRQOL in a Norwegian population‐based cohort of patients with IBD, measured with the SF‐36, is lower than that of a Norwegian reference population. In general, the SF‐36 was found to have satisfactory psychometric properties in this IBD population.

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Bjørn Moum

Oslo University Hospital

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Petr Ricanek

Akershus University Hospital

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Idar Lygren

Oslo University Hospital

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Simen Vatn

Akershus University Hospital

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Øistein Hovde

Innlandet Hospital Trust

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