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Dive into the research topics where Torbjørn Leivestad is active.

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Featured researches published by Torbjørn Leivestad.


Journal of The American Academy of Dermatology | 1999

Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens

Petter Jensen; Svein Hansen; Bjørn Møller; Torbjørn Leivestad; Per Pfeffer; Odd Geiran; Per Fauchald; Svein Simonsen

Abstract Background: Nonmelanoma skin cancer occurs frequently in organ transplant recipients, but the relative importance of different immunosuppressive therapy regimens is unclear. Objective: We studied the risk of skin cancer in the complete, single-center Norwegian cohort of kidney and heart transplant recipients (n = 2561). Methods: We determined cancer risk estimation by means of standardized incidence ratios and multivariate Cox regression. Results: Transplant recipients had an increased risk of cutaneous squamous cell carcinoma (SCC) (65-fold), malignant melanoma (3-fold), and Kaposis sarcoma (84-fold), and of lip SCC (20-fold), compared with the general population. After adjustment for age, kidney transplant recipients receiving cyclosporine, azathioprine, and prednisolone had a significantly (2.8 times) higher risk of cutaneous SCC relative to those receiving azathioprine and prednisolone. After adjustment for age and type of immunosuppressive regimen, heart transplant recipients had a significantly (2.9 times) higher risk than kidney transplant recipients. Conclusion: The risk of cutaneous SCC, malignant melanoma, Kaposis sarcoma, and lip SCC is increased in kidney and heart transplant recipients. The risk of posttransplant cutaneous SCC is related to the degree of immunosuppression caused by long-term immunosuppressive therapy. (J Am Acad Dermatol 1999;40:177-86.)


Kidney International | 2014

Long-term risks for kidney donors

Geir Mjøen; Stein Hallan; Anders Hartmann; Aksel Foss; Karsten Midtvedt; Ole Øyen; Anna Varberg Reisæter; Per Pfeffer; Trond Jenssen; Torbjørn Leivestad; Pål-Dag Line; Magnus Øvrehus; Dag Olav Dale; Hege Pihlstrøm; Ingar Holme; Friedo W. Dekker; Hallvard Holdaas

Previous studies have suggested that living kidney donors maintain long-term renal function and experience no increase in cardiovascular or all-cause mortality. However, most analyses have included control groups less healthy than the living donor population and have had relatively short follow-up periods. Here we compared long-term renal function and cardiovascular and all-cause mortality in living kidney donors compared with a control group of individuals who would have been eligible for donation. All-cause mortality, cardiovascular mortality, and end-stage renal disease (ESRD) was identified in 1901 individuals who donated a kidney during 1963 through 2007 with a median follow-up of 15.1 years. A control group of 32,621 potentially eligible kidney donors was selected, with a median follow-up of 24.9 years. Hazard ratio for all-cause death was significantly increased to 1.30 (95% confidence interval 1.11-1.52) for donors compared with controls. There was a significant corresponding increase in cardiovascular death to 1.40 (1.03-1.91), while the risk of ESRD was greatly and significantly increased to 11.38 (4.37-29.6). The overall incidence of ESRD among donors was 302 cases per million and might have been influenced by hereditary factors. Immunological renal disease was the cause of ESRD in the donors. Thus, kidney donors are at increased long-term risk for ESRD, cardiovascular, and all-cause mortality compared with a control group of non-donors who would have been eligible for donation.


Transplantation | 1997

Glucose intolerance after renal transplantation depends upon prednisolone dose and recipient age

Jøran Hjelmesæth; Anders Hartmann; Johan Kofstad; Jean Stenstrøm; Torbjørn Leivestad; Thore Egeland; P. Fauchald

BACKGROUND Retrospective studies on the prevalence of posttransplant diabetes mellitus (PTDM) in patients on triple-drug immunosuppressive therapy have shown great dispersity, while the incidence of posttransplant impaired glucose tolerance (IGT) is unknown. The aim of our study was to prospectively examine the incidence of posttransplant glucose intolerance and to assess potential risk factors. METHODS Glucose intolerance was prospectively examined in 173 consecutive kidney transplant recipients by oral glucose tolerance tests (n=167) or the diagnosis of manifest diabetes mellitus (n=6) at 10 weeks after transplant. RESULTS We found a high incidence of PTDM (18%) and IGT (31%). Univariate analysis revealed that age, family history of diabetes, HLA-B27 phenotype, DR mismatch, rejection, actual prednisolone dose, total methylprednisolone dose, total steroid dose, cytomegalovirus (CMV) infection, and the use of furosemide were associated with PTDM. Age, prednisolone dose, CMV infection, and the use of beta-blockers were associated with IGT. Gender, body mass index, donor source, and cyclosporine level did not influence glucose tolerance. Prednisolone dose, age, family history of diabetes, CMV infection, and HLA-B27 phenotype were independent predictors of PTDM with the use of multiple stepwise logistic regression analysis. Age, prednisolone dose, and the use of a beta-blocker were associated with IGT in the multivariate model. Both univariate and multivariate linear regression analysis revealed a significant relationship between the 2-hr serum glucose and prednisolone dose. The risk of developing PTDM was 5% per 0.01 mg/kg/day of increase in prednisolone dose. CONCLUSIONS Increased prednisolone dose and older age are strongly associated with the development of posttransplant glucose intolerance.


American Journal of Transplantation | 2002

The Impact of Cytomegalovirus Infection and Disease on Rejection Episodes in Renal Allograft Recipients

Solbjørg Sagedal; Knut P. Nordal; Anders Hartmann; Ståle Sund; Helge Scott; Miklos Degré; Aksel Foss; Torbjørn Leivestad; Kåre Osnes; Per Fauchald; Halvor Rollag

Cytomegalovirus (CMV) infection and disease are potential risk factors for acute allograft rejection in renal transplant recipients. The present study specifically addresses this issue. From October 1994 to July 1997, 477 consecutive renal allograft recipients (397 first transplants and 80 retransplants) were included in the study. CMV infection (cytomegalovirus pp65 antigen in leukocytes) and disease (infection and clinical symptoms or signs of disease) were examined prospectively for 3 months. No CMV prophylaxis was given, and CMV disease was treated with intravenous (i.v.) ganciclovir. The retransplantation of four patients transplanted twice during the study and 22 patients receiving kidneys from human leucocyte antigen (HLA)‐identical siblings were excluded from statistical analysis. Rejections were evaluated clinically [277(61%)] and 173 (38%) also had a biopsy verified rejection. CMV infection occurred in 64% of the patients and 24% experienced CMV disease. In a multiple time‐dependent Cox analysis, CMV infection and CMV disease were independent significant predictors for clinical acute rejections, RR = 1.6 (1.1–2.5, p = 0.02) and RR = 2.5 (1.2–5.1, p = 0.01), respectively. Among 173 patients with biopsy verified rejection, 72% of the patients had tubulointerstitial rejection whereas 28% had a vascular rejection. CMV disease, but not CMV infection was a predictor of tubulointerstitial rejection, RR = 3.1 (1.1–9.3, p = 0.04). CMV infection and disease are independent risk factors for clinical acute rejection in kidney allograft recipients. CMV disease is an independent risk factor for biopsy verified acute tubulointerstitial rejection in kidney allograft recipients.


Journal of The American Society of Nephrology | 2008

Low Birth Weight Increases Risk for End-Stage Renal Disease

Bjørn Egil Vikse; Lorentz M. Irgens; Torbjørn Leivestad; Stein Hallan; Bjarne M. Iversen

Case-control studies have shown an association between low birth weight and risk for renal failure. The Medical Birth Registry of Norway, which comprises data on all births in Norway since 1967, and the Norwegian Renal Registry, which comprises data on all patients who have developed ESRD in Norway since 1980, were used to examine whether birth-related variables were associated with risk for ESRD. Of the 2,183,317 children born between 1967 and 2004, 526 were found in the ESRD registry. Compared with birth weight in the 10th to 90th percentiles, births <10th percentile had a relative risk (RR) for ESRD of 1.7 (95% confidence interval 1.4 to 2.2; P < 0.001). Births with a weight for gestational age <10th percentile had an RR of 1.5 (95% confidence interval 1.2 to 1.9; P = 0.002). These associations were virtually identical after adjustment for birth-related confounders such as congenital malformations, multiple delivery, maternal age at birth, and maternal preeclampsia. Low birth weight was more strongly associated with development of ESRD during the first 14 years of life than after age 15. Low birth weight and low birth weight for gestational age were similarly associated with multiple causes of ESRD. In conclusion, in this cohort study with a maximum follow-up of 38 years, low birth weight and intrauterine growth restriction were associated with increased risk for ESRD.


Transplantation | 2000

A prospective study of the natural course of cytomegalovirus infection and disease in renal allograft recipients.

Solbjørg Sagedal; Knut P. Nordal; Anders Hartmann; Miklos Degré; Ellen Holter; Aksel Foss; Kåre Osnes; Torbjørn Leivestad; P. Fauchald; Halvor Rollag

Background. Cytomegalovirus (CMV) infection is the single most frequent infectious complication inrenal transplant recipients. Because no CMV-prophylaxis is given and ganciclovir is used only as deferred therapy for CMV disease at our center, we have been able to study the natural course of CMV infections. The aim was to assess risk factors for CMV infection and disease and thus identify subgroups of patients likely to benefit from CMV prophylaxis or preemptive therapy. Methods. Between October 1994 and July 1997, 477 consecutive renal transplant recipients (397 first transplants and 80 retransplants) were included in the study. The patients were followed prospectively for 3 months with serial measurements of CMV pp65 antigen for monitoring activity of CMV infections. Results. The incidence of CMV infections in first transplants was 68% in D+R− and D±R+ serostatus groups, whereas the incidence of CMV disease was higher in D+R− (56%) than in D±R+ (20%, P <0.001). No difference in severity of CMV disease in D+R− and D±R+ was seen except for an increased incidence of hepatitis in primary infections. One of 14 deaths could be associated with CMV disease in a seropositive recipient. Cox regression analysis showed that rejection (RR 2.5, P <0.01) and serostatus group D+R− (RR 3.9, P <0.001) were significant risk factors for development of CMV disease. The maximum CMV pp65 antigen count had significant correlation to disease only in CMV seropositive recipients, P <0.001. Conclusion. Renal transplant recipients can safely be given deferred ganciclovir therapy for CMV disease if they are intensively monitored for CMV infection. Patients with primary CMV infection (D+R−), CMV infected patients undergoing anti-rejection therapy and R+ patients with high CMV pp65 counts seem to have a particular potential for benefit from preemptive anti-CMV-therapy.


Journal of Immunological Methods | 1986

Isolation of pure functionally active CD8+ T cells positive selection with monoclonal antibodies directly conjugated to monosized magnetic microspheres

Gustav Gaudernack; Torbjørn Leivestad; John Ugelstad; Erik Thorsby

A monoclonal antibody of the IgM isotype, ITI-5C2, which binds with high affinity to CD8 molecules, was directly conjugated to the monosized magnetic microspheres M-450. This permits selective removal of the CD8+ T cell subset (T8) from peripheral blood mononuclear cell suspensions in a rapid one-step procedure. With a low ratio of microspheres to cells (2:1), functionally active T8 cells can be recovered. In vitro experiments involving such positively selected T8 cells or recombinations of isolated T8 and T4 subsets, demonstrate that the presence of M-450 microspheres coated with ITI-5C2 do not interfere with the immunological functions of the positively selected cells. The method has possible application in the isolation of all cell populations where high avidity mAbs of appropriate specificity are available.


Journal of The American Society of Nephrology | 2006

International Differences in Dialysis Mortality Reflect Background General Population Atherosclerotic Cardiovascular Mortality

Maki Yoshino; Martin K. Kuhlmann; Peter Kotanko; Roger Greenwood; Ronald L. Pisoni; Friedrich K. Port; Kitty J. Jager; Peter Homel; Hans Augustijn; Frank de Charro; Frederic Collart; Ekrem Erek; Patrik Finne; Guillermo Garcia-Garcia; Carola Grönhagen-Riska; George A. Ioannidis; Frank Ivis; Torbjørn Leivestad; Hans Løkkegaard; Frantisek Lopot; Dong-Chan Jin; Reinhard Kramar; Toshiyuki Nakao; Mooppil Nandakumar; Sylvia P. B. Ramirez; Frank M. van der Sande; Staffan Schon; Keith Simpson; Rowan G. Walker; Wojciech Zaluska

Existing national, racial, and ethnic differences in dialysis patient mortality rates largely are unexplained. This study aimed to test the hypothesis that mortality rates related to atherosclerotic cardiovascular disease (ASCVD) in dialysis populations (DP) and in the background general populations (GP) are correlated. In a cross-sectional, multinational study, all-cause and ASCVD mortality rates were compared between GP and DP using the most recent data from the World Health Organization mortality database (67 countries; 1,571,852,000 population) and from national renal registries (26 countries; 623,900 population). Across GP of 67 countries (14,082,146 deaths), all-cause mortality rates (median 8.88 per 1000 population; range 1.93 to 15.40) were strongly related to ASCVD mortality rates (median 3.21; range 0.53 to 8.69), with Eastern European countries clustering in the upper and Southeast and East Asian countries in the lower rate ranges. Across DP (103,432 deaths), mortality rates from all causes (median 166.20; range 54.47 to 268.80) and from ASCVD (median 63.39 per 1000 population; range 21.52 to 162.40) were higher and strongly correlated. ASCVD mortality rates in DP and in the GP were significantly correlated; the relationship became even stronger after adjustment for age (R(2) = 0.56, P < 0.0001). A substantial portion of the variability in mortality rates that were observed across DP worldwide is attributable to the variability in background ASCVD mortality rates in the respective GP. Genetic and environmental factors may underlie these differences.


Nephrology Dialysis Transplantation | 2009

An update on renal replacement therapy in Europe: ERA–EDTA Registry data from 1997 to 2006

Anneke Kramer; Vianda S. Stel; Carmine Zoccali; James G. Heaf; David Ansell; Carola Grönhagen-Riska; Torbjørn Leivestad; Keith Simpson; Runolfur Palsson; Kitty J. Jager

BACKGROUND Recent studies have indicated a stabilization in the incidence rates of renal replacement therapy (RRT) for end-stage renal disease (ESRD) in a number of European countries. The aim of this study was to provide an update on the incidence, prevalence and outcomes of RRT in Europe over the past decade. METHODS Nineteen European national or regional renal registries with registry data from 1997 to 2006 participated in the study. Incidence and prevalence trends were analysed with Poisson and Joinpoint regression. Cox regression methods were used to examine patient survival. RESULTS The total adjusted incidence rate of RRT for ESRD increased from 109.9 per million population (pmp) in 1997 to 119.7 pmp in 2000, i.e. an average annual percentage change (AAPC) of 2.9% (95% CI 2.1-3.8%). Thereafter, the incidence increased at a much lower rate to 125.4 pmp in 2006 [AAPC 0.6% (95% CI 0.3-0.8%)]. This change in the trend of the incidence of RRT was largely due to a stabilization in the incidence rates of RRT for females aged 65-74 years, males aged 75-84 years and patients receiving RRT for ESRD due to hypertension/renal vascular disease. The overall adjusted prevalence in Europe continued to increase linearly at 2.7% per year. Between the periods 1997-2001 and 2002-2006, the risk of death decreased for all treatment modalities, with the most substantial improvement in patients starting peritoneal dialysis [19% (95% CI 15-22%)] and in patients receiving a kidney transplant [17% (95% CI 11-23%)]. CONCLUSION This European study shows that the annual rise of the overall incidence rate of RRT for ESRD has diminished and that in several age groups the incidence rates have now stabilized. The survival of dialysis patients and kidney transplant recipients has continued to improve.


Ndt Plus | 2012

Renal replacement therapy in Europe: a summary of the 2012 ERA-EDTA Registry Annual Report

Maria Pippias; Vianda S. Stel; Nikolaos Afentakis; Jose Antonio Herrero-Calvo; Manuel Arias; Natalia Tomilina; Encarnación Bouzas Caamaño; Jadranka Buturovic-Ponikvar; Svjetlana Čala; Fergus Caskey; Harijs Cernevskis; Frédéric Collart; Ramón Alonso de la Torre; Maria de los Ángeles García Bazaga; Johan De Meester; Joan M. Díaz; Ljubica Djukanovic; Manuel Ferrer Alamar; Patrik Finne; Liliana Garneata; Eliezer Golan; Raquel González Fernández; Gonzalo Gutiérrez Avila; James G. Heaf; Andries J. Hoitsma; Nino Kantaria; Mykola Kolesnyk; Reinhard Kramar; Anneke Kramer; Mathilde Lassalle

Background This article summarizes the 2012 European Renal Association—European Dialysis and Transplant Association Registry Annual Report (available at www.era-edta-reg.org) with a specific focus on older patients (defined as ≥65 years). Methods Data provided by 45 national or regional renal registries in 30 countries in Europe and bordering the Mediterranean Sea were used. Individual patient level data were received from 31 renal registries, whereas 14 renal registries contributed data in an aggregated form. The incidence, prevalence and survival probabilities of patients with end-stage renal disease (ESRD) receiving renal replacement therapy (RRT) and renal transplantation rates for 2012 are presented. Results In 2012, the overall unadjusted incidence rate of patients with ESRD receiving RRT was 109.6 per million population (pmp) (n = 69 035), ranging from 219.9 pmp in Portugal to 24.2 pmp in Montenegro. The proportion of incident patients ≥75 years varied from 15 to 44% between countries. The overall unadjusted prevalence on 31 December 2012 was 716.7 pmp (n = 451 270), ranging from 1670.2 pmp in Portugal to 146.7 pmp in the Ukraine. The proportion of prevalent patients ≥75 years varied from 11 to 32% between countries. The overall renal transplantation rate in 2012 was 28.3 pmp (n = 15 673), with the highest rate seen in the Spanish region of Catalonia. The proportion of patients ≥65 years receiving a transplant ranged from 0 to 35%. Five-year adjusted survival for all RRT patients was 59.7% (95% confidence interval, CI: 59.3–60.0) which fell to 39.3% (95% CI: 38.7–39.9) in patients 65–74 years and 21.3% (95% CI: 20.8–21.9) in patients ≥75 years.

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Aksel Foss

Oslo University Hospital

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Kitty J. Jager

Public Health Research Institute

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Trond Jenssen

Oslo University Hospital

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