Elisabeth Lie

Diakonhjemmet Hospital (Norway), Oslo, Oslo, Norway

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Publications (39)180.63 Total impact

  • Article: Switching between TNF inhibitors in psoriatic arthritis: data from the NOR-DMARD study.
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    ABSTRACT: BACKGROUND: Tumour necrosis factor inhibitors (TNFi) are efficacious in patients with psoriatic arthritis (PsA), but some patients do not respond or do not tolerate their first TNFi, and are switched to a different TNFi. Evidence supporting this practice is limited, and we wanted to investigate the effectiveness of switching to a second TNFi. MATERIAL AND METHODS: From a longitudinal observational study (LOS) we selected patients with PsA who were starting their first TNFi, and identified patients who had switched to a second TNFi ('switchers'). Three-month responses and 3-year drug-survival were compared between switchers and non-switchers, and within switchers. RESULTS: Switchers (n=95) receiving their second TNFi had significantly poorer responses compared with non-switchers (n=344) (ACR50 response: 22.5% vs 40.0%, DAS28 remission: 28.2% vs 54.1%). There was a trend towards poorer responses to the second TNFi compared with the first TNFi within switchers. Estimated 3-year drug-survival was 36% for the second TNFi compared with 57% for the first TNFi overall. CONCLUSIONS: 20-40% of patients had a response on a second TNFi after having failed one TNFi in this LOS. This observation highlights the need for treatments with other mechanisms of action than TNF inhibition in patients with PsA.
    Annals of the rheumatic diseases 04/2013; · 8.11 Impact Factor
  • Article: Transthyretin-Binding Activity of Contaminants in Blood from Polar Bear (Ursus maritimus) Cubs.
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    ABSTRACT: We determined the transthyretin (TTR)-binding activity of blood-accumulating contaminants in blood plasma samples of approximately 4-months-old polar bear (Ursus maritimus) cubs from Svalbard sampled in 1998 and 2008. The TTR-binding activity was measured as thyroxine (T4)-like equivalents (T4-EQMeas). Our findings show that the TTR-binding activity related to contaminant levels was significantly lower (45%) in 2008 than in 1998 (mean ± standard error of mean: 1998, 2265 ± 231 nM; 2008, 1258 ± 170 nM). Although we cannot exclude a potential influence of between-year differences in capture location and cub body mass, our findings most likely reflect reductions of TTR-binding contaminants or their precursors in the arctic environment (e.g., polychlorinated biphenyls [PCBs]). The measured TTR-binding activity correlated positively with the cubs' plasma levels of hydroxylated PCBs (OH-PCBs). No such association was found between TTR-binding activity and the plasma levels of perfluoroalkyl substances (PFASs). The OH-PCBs explained 60 ± 7% and 54 ± 4% of the TTR-binding activity in 1998 and 2008, respectively, and PFASs explained ≤1.2% both years. Still, almost half the TTR-binding activity could not be explained by the contaminants we examined. The considerable levels of TTR-binding contaminants warrant further effect directed analysis (EDA) to identify the contaminants responsible for the unexplained part of the observed TTR-binding activity.
    Environmental Science & Technology 04/2013; · 4.80 Impact Factor
  • Article: The role of methotrexate co-medication in TNF-inhibitor treatment in patients with psoriatic arthritis: results from 440 patients included in the NOR-DMARD study.
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    ABSTRACT: BACKGROUND: The role of co-medication with tumour necrosis factor inhibitors (TNFi) is well established in rheumatoid arthritis and ankylosing spondylitis. In psoriatic arthritis (PsA) there is little evidence available on this issue. MATERIAL AND METHODS: The analyses were based on data from the Norwegian longitudinal observational study on disease-modifying antirheumatic drugs (NOR-DMARD). Patients with PsA starting their first TNFi, either as monotherapy or with concomitant methotrexate (MTX), were selected. Baseline characteristics, responses after 3, 6 and 12 months, and drug survival were compared between those with and without MTX co-medication. A secondary analysis was performed on patients who had confirmed swollen joints at baseline. Cox regression was used to identify predictors of discontinuation. RESULTS: We included 440 patients, 170 receiving TNFi as monotherapy and 270 receiving concomitant MTX. The groups had similar baseline characteristics, except for number of swollen joints, which was higher in the concomitant MTX group. Responses were similar in the two groups in both analyses. Drug survival analyses revealed a borderline significant difference in favour of patients receiving co-medication (p=0.07), and this was most prominent for patients receiving infliximab (IFX) (p=0.01). In the Cox regression analysis lack of concomitant MTX and current smoking were independent predictors of discontinuation of TNFi. CONCLUSIONS: We found similar responses to TNFi in patients with and without concomitant MTX, but drug survival was superior in patients receiving co-medication. The effect of MTX on drug survival was most prominent in patients receiving IFX. Smoking at baseline and use of TNFi as monotherapy were identified as independent predictors of drug discontinuation.
    Annals of the rheumatic diseases 01/2013; · 8.11 Impact Factor
  • Article: High prevalence of infections and pathological changes in burbot (Lota lota) from a polluted lake (Lake Mjøsa, Norway).
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    ABSTRACT: The aim of the present study was to investigate whether exposure to high levels of persistent organic pollutants (POPs) affected a fish population in Lake Mjøsa. Lake Mjøsa is known to be contaminated by polybrominated diphenyl ethers (PBDEs), a subgroup of brominated flame retardants from local industrial activities. Fish from Lake Losna, a less contaminated lake located close to Lake Mjøsa, was used as reference (control). The sampling of burbot (Lota lota) was carried out between 2005 and 2008. Hepatic levels of POPs were analysed in burbot from the two lakes, and the fish were examined for bacterial- and parasite infection and histopathological changes. The levels of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), and PBDEs were about 10, 15 and 300times higher in fish from Lake Mjøsa compared to fish from Lake Losna. Mycobacterium salmoniphilum was present in 7% and 35% of the fish from Lake Losna and Lake Mjøsa respectively. Significantly higher number of external and visceral macroscopic lesions, histopathological diffuse changes and granulomas were seen in fish from Lake Mjøsa compared to Lake Losna. Furthermore the parasite infection was higher and the hepatic lipid content was significantly lower in burbot from Lake Mjøsa. The results of the present study suggest that the high level of contamination in Lake Mjøsa could have a negative impact on the health status of wild fish inhabiting the lake.
    Chemosphere 11/2012; · 3.21 Impact Factor
  • Article: Perfluoroalkyl substances in polar bear mother-cub pairs: A comparative study based on plasma levels from 1998 and 2008.
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    ABSTRACT: Perfluoroalkyl substances (PFASs) are protein-binding blood-accumulating contaminants that may have detrimental toxicological effects on the early phases of mammalian development. To enable an evaluation of the potential health risks of PFAS exposure for polar bears (Ursus maritimus), an exposure assessment was made by examining plasma levels of PFASs in polar bear mothers in relation to their suckling cubs-of-the-year (~4months old). Samples were collected at Svalbard in 1998 and 2008, and we investigated the between-year differences in levels of PFASs. Seven perfluorinated carboxylic acids (∑(7)PFCAs: PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, and PFTrDA) and two perfluorinated sulfonic acids (∑(2)PFSAs: PFHxS and PFOS) were detected in the majority of the mothers and cubs from both years. In mothers and cubs, most PFCAs were detected in higher concentrations in 2008 than in 1998. On the contrary, levels of PFOS were lower in 2008 than in 1998, while levels of PFHxS did not differ between the two sampling years. PFOS was the dominating compound in mothers and cubs both in 1998 and in 2008. Concentration of PFHpA did not differ between mothers and cubs, while concentrations of PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFTrDA, PFHxS, and PFOS were higher in mothers than in their cubs. Except from PFHpA, all compounds correlated significantly between mothers and their cubs. The mean cub to mother ratios ranged from 0.15 for PFNA to 1.69 for PFHpA. On average (mean±standard error of mean), the levels of ∑(7)PFCAs and ∑(2)PFSAs in cubs were 0.24±0.01 and 0.22±0.01 times the levels in their mothers, respectively. Although maternal transfer appears to be a substantial source of exposure for the cubs, the low cub to mother ratios indicate that maternal transfer of PFASs in polar bears is relatively low in comparison with hydrophobic contaminants (e.g. PCBs). Because the level of several PFASs in mothers and cubs from both sampling years exceeded the levels associated with health effects in humans, our findings raise concern on the potential health effects of PFASs in polar bears from Svalbard. Effort should be made to examine the potential health effects of PFASs in polar bears.
    Environment international 09/2012; 49C:92-99. · 4.79 Impact Factor
  • Article: Mercury in molar excess of selenium interferes with thyroid hormone function in free-ranging freshwater fish.
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    ABSTRACT: Thyroid hormones (THs) are essential for cellular metabolism, somatic growth and development, and reproduction. Mercury (Hg) entering aquatic systems and accumulated as highly toxic methylmercury (MeHg) represents a threat to wildlife and human health. Selenium (Se) is an essential element critical for TH activation and regulation. In organisms, binding of Hg in a Se-Hg complex results in a detoxification of Hg. However, formation of Se-Hg complexes also affects Se bioavailability, disrupting functions of Se-dependent enzymes, such as TH deiodinases, which convert thyroxine (T4) to the physiologically active TH, triiodothyronine (T3). The main aim of the present study was to investigate how tissue Se:Hg molar ratios, tissue levels of Se and Hg, and other potential TH disruptive contaminants (metals and organic chemical compounds) affect plasma TH levels in free-ranging brown trout, Salmo trutta , from Lake Mjøsa (a Se-deprived lake) and Lake Losna (a reference lake), Norway. Among the wide range of potential TH disruptive pollutants investigated, tissue Se:Hg molar ratios in muscle and liver were the most significant predictors of plasma TH levels in the trout. Moreover, lower plasma levels of the biological active hormone, T3, in the Lake Mjøsa trout co-occurred with their low Se:Hg molar ratios. This suggests that Se availability is impaired by Hg and results in altered selenoenzyme activities and loss of optimal control of TH balance in free-ranging freshwater fish.
    Environmental Science & Technology 07/2012; 46(16):9027-37. · 4.80 Impact Factor
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    Article: Eggshell thinning and decreased concentrations of vitamin E are associated with contaminants in eggs of ivory gulls.
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    ABSTRACT: The ivory gull is a high Arctic seabird species threatened by climate change and contaminant exposure. High levels of contaminants have been reported in ivory gull Pagophila eburnea eggs from Svalbard and the Russian Arctic. The present study investigated associations between high levels of contaminants (organochlorinated pesticides (OCPs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs), perfluorinated alkyl substances (PFASs) and mercury (Hg)) and three response variables: eggshell thickness, retinol (vitamin A) and α-tocopherol (vitamin E). Negative associations were found between levels of OCPs, PCBs and BFRs and eggshell thickness (p<0.021) and α-tocopherol (p<0.023), but not with retinol (p>0.1). There were no associations between PFASs and mercury and the three response variables. Furthermore, the eggshell thickness was 7-17% thinner in the present study than in archived ivory gull eggs (≤1930). In general, a thinning above 16 to 20% has been associated with a decline in bird populations, suggesting that contaminant-induced eggshell thinning may constitute a serious threat to ivory gull populations globally.
    Science of The Total Environment 06/2012; 431:92-9. · 3.29 Impact Factor
  • Article: Two-year direct and indirect costs for patients with inflammatory rheumatic joint diseases: data from real-life follow-up of patients in the NOR-DMARD registry.
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    ABSTRACT: The overall aim of this study was to estimate the total costs for patients with RA, AS and psoriatic arthritis (PsA) treated with DMARDs. Specific aims were to compare the costs across diagnoses and over time. The main data source was the Norwegian DMARD register (NOR-DMARD) that captures outcomes and resource use among patients starting therapy with synthetic and biologic DMARDs. Costs were estimated for four 6-month periods from the start of a DMARD regimen. We included RA (n=1152), AS (n=186) and PsA (n=374) patients with available 2-year data. Direct costs included pharmaceuticals, imaging examinations, in-hospital and out-hospital care, stays in rehabilitation units and visits to general practitioners, private rheumatologists and physiotherapists. Indirect cost included patients' work absenteeism. Differences in costs across diagnoses were tested by Kruskal-Wallis equality-of-populations rank test and changes in costs between first and fourth 6-month periods were tested by paired t-tests. Total 2-year costs were similar across diagnoses for patients on synthetic treatment (RA/AS/PsA €64,300/63,200/64,500) and on biologic treatment (€121,900/115,319/111,200). The largest cost component was productivity loss. Total costs decreased significantly from the first to the fourth 6-month periods for all diagnoses, and this decrease was influenced by reductions both in direct and indirect costs. Total costs were similar across the main inflammatory rheumatic diseases. Biologic DMARD treatment entails considerable drug cost, but the total costs decline during the first 2 years on treatment in both RA, AS and PsA.
    Rheumatology (Oxford, England) 04/2012; 51(9):1618-27. · 4.24 Impact Factor
  • Article: Selecting patients with ankylosing spondylitis for TNF inhibitor therapy: comparison of ASDAS and BASDAI eligibility criteria.
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    ABSTRACT: To compare Ankylosing Spondylitis Disease Activity Score (ASDAS) ≥2.1 with BASDAI >4 as an eligibility criterion for initiation of TNF inhibitor (TNFi) treatment in AS, and to investigate if ASDAS performs satisfactorily in patients without elevated CRP or without peripheral joint swelling. Two hundred and eighty-nine patients starting their first TNFi were identified from a longitudinal observational study (NOR-DMARD) and grouped according to the fulfilment of ASDAS and BASDAI TNFi eligibility criteria. The 3-month responses were compared across several response measures. Patients were also grouped according to CRP level and the presence or absence of swollen joints, and responses were compared. The majority of patients (n = 212) fulfilled both eligibility criteria, and this group had the best response. Very few patients (n = 4) fulfilled only the BASDAI criterion. Patients fulfilling only the ASDAS criterion (n = 48) had a reasonable response. Patients with an elevated vs not elevated CRP at baseline had better responses according to all response measures, but patients without elevated CRP also responded. We also observed trends towards better responses in patients with vs without peripheral joint swelling. More patients were eligible for TNFi using the ASDAS than the BASDAI eligibility criterion (n = 260 vs n = 216). Fulfilment of both criteria gave the greatest likelihood of improvement, but the patients who only fulfilled the ASDAS criterion also improved. ASDAS was found to be applicable also in subgroups without elevated CRP and without peripheral joint swelling.
    Rheumatology (Oxford, England) 04/2012; 51(8):1479-83. · 4.24 Impact Factor
  • Article: Effectiveness of disease-modifying antirheumatic drug co-therapy with methotrexate and leflunomide in rituximab-treated rheumatoid arthritis patients: results of a 1-year follow-up study from the CERERRA collaboration.
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    ABSTRACT: To compare the effectiveness and safety of rituximab alone or in combination with either methotrexate or leflunomide. 10 European registries submitted anonymised datasets with baseline, 3, 6, 9 and 12-month clinical data from patients who started rituximab. 1195 patients were treated with rituximab plus methotrexate, 177 with rituximab plus leflunomide and 505 with rituximab alone. Significantly more patients achieved a European League Against Rheumatism good response at 6 months when treated with rituximab plus leflunomide (29.1%) compared with rituximab plus methotrexate (21.1%) and rituximab alone (19.3%; p=0.02 and p=0.01, respectively). Similar results were observed at 12 months. Adverse events occurred in 10.2%, 13.2% and 13.9% of patients on rituximab plus leflunomide, rituximab plus methotrexate and rituximab alone, respectively. Leflunomide is an effective and safe alternative to methotrexate as concomitant treatment with rituximab. Slightly better results were obtained by the combination of rituximab and leflunomide than rituximab and methotrexate, raising the possibility of a synergistic effect of leflunomide and rituximab.
    Annals of the rheumatic diseases 03/2012; 71(3):374-7. · 8.11 Impact Factor
  • Article: PCBs and OH-PCBs in polar bear mother-cub pairs: a comparative study based on plasma levels in 1998 and 2008.
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    ABSTRACT: The aim of this study was to examine the plasma concentrations and prevalence of polychlorinated biphenyls (PCBs) and hydroxylated PCB-metabolites (OH-PCBs) in polar bear (Ursus maritimus) mothers (n=26) and their 4 months old cubs-of-the-year (n=38) from Svalbard to gain insight into the mother-cub transfer, biotransformation and to evaluate the health risk associated with the exposure to these contaminants. As samplings were performed in 1997/1998 and 2008, we further investigated the differences in levels and pattern of PCBs between the two sampling years. The plasma concentrations of Σ(21)PCBs (1997/1998: 5710 ± 3090 ng/g lipid weight [lw], 2008: 2560 ± 1500 ng/g lw) and Σ(6)OH-PCBs (1997/1998: 228 ± 60 ng/g wet weight [ww], 2008: 80 ± 38 ng/g ww) in mothers were significantly lower in 2008 compared to in 1997/1998. In cubs, the plasma concentrations of Σ(21)PCBs (1997/1998: 14680 ± 5350 ng/g lw, 2008: 6070 ± 2590 ng/g lw) and Σ(6)OH-PCBs (1997/1998: 98 ± 23 ng/g ww, 2008: 49 ± 21 ng/g ww) were also significantly lower in 2008 than in 1997/1998. Σ(21)PCBs in cubs was 2.7 ± 0.7 times higher than in their mothers. This is due to a significant maternal transfer of these contaminants. In contrast, Σ(6)OH-PCBs in cubs were approximately 0.53 ± 0.16 times the concentration in their mothers. This indicates a lower maternal transfer of OH-PCBs compared to PCBs. The majority of the metabolite/precursor-ratios were lower in cubs compared to mothers. This may indicate that cubs have a lower endogenous capacity to biotransform PCBs to OH-PCBs than polar bear mothers. Exposure to PCBs and OH-PCBs is a potential health risk for polar bears, and the levels of PCBs and OH-PCBs in cubs from 2008 were still above levels associated with health effects in humans and wildlife.
    Science of The Total Environment 02/2012; 417-418:117-28. · 3.29 Impact Factor
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    Article: Eggshell thinning and decreased concentrations of vitamin E are associated with contaminants in eggs of ivory gulls
    [show abstract] [hide abstract]
    ABSTRACT: The ivory gull is a high Arctic seabird species threatened by climate change and contaminant exposure. High levels of contaminants have been reported in ivory gull Pagophila eburnea eggs from Svalbard and the Russian Arctic. The present study investigated associations between high levels of contaminants (organochlorinated pesticides (OCPs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs), perfluorinated alkyl substances (PFASs) and mercury (Hg)) and three response variables: eggshell thickness, retinol (vitamin A) and α-tocopherol (vitamin E). Negative associations were found between levels of OCPs, PCBs and BFRs and eggshell thickness (p b 0.021) and α-tocopherol (p b 0.023), but not with retinol (p > 0.1). There were no associations between PFASs and mercury and the three response variables. Furthermore, the eggshell thickness was 7–17% thinner in the present study than in archived ivory gull eggs (≤1930). In general, a thinning above 16 to 20% has been associated with a decline in bird populations, suggesting that contaminant-induced eggshell thinning may constitute a serious threat to ivory gull populations globally.
    Science of The Total Environment 01/2012; · 3.29 Impact Factor
  • Article: Effectiveness of sulfasalazine and methotrexate in 1102 DMARD-naive patients with early RA.
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    ABSTRACT: To compare baseline characteristics, responses and drug survival in patients with early RA starting SSZ or MTX in a real-life setting. The analyses included DMARD-naïve patients with RA (disease duration ≤ 1 year) starting SSZ or MTX. Three- and 6-month effectiveness was compared by unadjusted analysis and with adjustment for propensity score quintile. In addition, effectiveness in SSZ- and MTX-treated patients matched for RF status and baseline DAS-28 was compared. SSZ-treated patients (n = 175) had lower baseline disease activity than patients treated with MTX (n = 927) [mean 28-joint DAS (DAS-28) 4.4 vs 5.0, P < 0.001], and were less often RF positive (50 vs 61%, P = 0.006). Six-month mean ΔDAS-28 was smaller with SSZ than MTX (-1.0 vs -1.5, P = 0.003); the difference was not significant after adjustment for propensity score quintile (P = 0.36). For SSZ/MTX, 3-month ACR50 and European League Against Rheumatism (EULAR) good responses were 9/23% (P < 0.001) and 24/31% (P = 0.14), respectively. Three-year drug survival was superior for MTX (P < 0.001) and estimated 1-year survival rates were 42/75% for SSZ/MTX. In patients matched for baseline DAS-28 and RF, mean ΔDAS-28 (MTX -1.2, P = 0.55 vs SSZ) and EULAR good responses (39 vs 37%, P = 0.74) were similar at 6 months; drug survival was superior for MTX (P < 0.001). Patients treated with SSZ as first DMARD were more often RF negative and had lower baseline disease activity. Drug survival was superior for MTX, and effectiveness was greater with MTX than with SSZ although the difference was reduced when adjusting for differences in baseline characteristics.
    Rheumatology (Oxford, England) 12/2011; 51(4):670-8. · 4.24 Impact Factor
  • Article: Treatment strategies in patients with rheumatoid arthritis for whom methotrexate monotherapy has failed: data from the NOR-DMARD register.
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    ABSTRACT: To compare the effectiveness of adding synthetic disease-modifying antirheumatic drugs (sDMARDs) versus tumour necrosis factor α inhibitors (TNFi) to methotrexate (MTX) in patients with rheumatoid arthritis (RA) who were MTX inadequate responders (IR). Second, to examine outcomes in patients receiving MTX+TNFi for whom the MTX+sDMARD combination had also failed. Patients with RA (disease duration ≤ 5 years, MTX IR and naïve to other DMARDs) starting treatment with MTX+TNFi or MTX+sDMARDs were included. From the latter group a subgroup of patients who went on to receive MTX+TNFi was identified. Patients receiving MTX+TNFi (n=98) and MTX+sDMARDs (n=129) had similar baseline disease activity when starting combination therapy (mean Disease Activity Score 28 (DAS28) = 4.90 and 4.96, respectively). Three- and 6-month effectiveness and 2-year drug survival were better for MTX+TNFi than for MTX+sDMARDs: mean DAS28 was -1.61 versus -0.85 after 3 months (p<0.001) and -1.91 versus -1.03 after 6 months (p=0.01); DAS28<2.6 was reached by 29.0% versus 11.6% after 3 and 34.5% versus 12.9% after 6 months. Effectiveness was somewhat better with triple therapy than other MTX+sDMARD combinations but was generally inferior compared with MTX+TNFi. For the patients who received MTX+TNFi as a third step after MTX+sDMARDs had failed (n=38) there was a tendency towards lower remission rates, worse disease activity states and inferior drug survival compared with patients who received MTX+TNFi directly after the failure of MTX. Effectiveness was better for MTX+TNFi than for MTX+sDMARDs. Patients who started MTX+TNFi after two synthetic DMARD regimens had failed had a tendency to less favourable disease states after 3 months than patients who switched directly from MTX to MTX+TNFi.
    Annals of the rheumatic diseases 08/2011; 70(12):2103-10. · 8.11 Impact Factor
  • Article: Blood plasma sample preparation method for the assessment of thyroid hormone-disrupting potency in effect-directed analysis.
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    ABSTRACT: A sample preparation method combining solid-phase extraction (SPE) and liquid-liquid extraction (LLE) was developed to be used in Effect-Directed Analysis (EDA) of blood plasma. Until now such a method was not available. It can be used for extraction of a broad range of thyroid hormone (TH)-disruptors from plasma with high recoveries. Validation of the method using spiked cow plasma showed good recoveries for hydroxylated polybrominated diphenyl ethers (OH-PBDEs; 93.8 ± 19.5%), hydroxylated polychlorinated biphenyls (OH-PCBs; 93.8 ± 15.5%), other halogenated phenols (OHPs; 107 ± 8.1%), and for short-chain (<8 C-atoms) perfluoroalkyl substances (PFASs; 85.2 ± 24.6%). In the same extracts, the potency of the compound classes spiked to the cow plasma to competitively bind to transthyretin (TTR) was recovered by 84.9 ± 8.8%. Furthermore, the SPE-LLE method efficiently removed endogenous THs from the extracts, thereby eliminating their possible contribution to the binding assay response. The SPE-LLE method was applied to polar bear plasma samples to investigate its applicability in future EDA studies focusing on TH-disrupting compounds in this top predator species that is exposed to relatively high levels of bioaccumulating pollutants. A first screening revealed TTR-binding potency in the polar bear plasma extracts, which could be explained for 60-85% by the presence of OH-PCBs.
    Environmental Science & Technology 08/2011; 45(18):7936-44. · 4.80 Impact Factor
  • Article: Levels and patterns of hydroxylated polychlorinated biphenyls (OH-PCBs) and their associations with thyroid hormones in hooded seal (Cystophora cristata) mother-pup pairs.
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    ABSTRACT: Blood (plasma/serum) samples from 14 adult female and their pups (1-4 days old) captured in the West Ice, east of Greenland were analysed for concentrations of total and free thyroxine and triiodothyronine (TT4, FT4, TT3, FT3), and hydroxylated polychlorinated biphenyls (OH-PCBs). The levels of all thyroid hormones (THs) were significantly higher in pups than in mothers. Sum OH-PCB levels (ΣOH-PCBs: 4-OH-CB107, 3'-OH-CB138, 4-OH-CB146, 4'-OH-CB172, 4-OH-CB187) were significantly higher in mothers (3.98 ± 1.55 pmol/g; 1.40 ± 0.54 ng/g wet weight) as compared to pups (1.95 ± 0.78 pmol/g; 0.68 ± 0.28 ng/g wet weight). Plasma levels of TT4 and FT4 in mothers increased as a function of pup age, as did levels of individual OH-PCBs in both mothers and pups. The pattern of OH-PCBs in the pups was similar to their mothers. We suggest that OH-PCBs found in pups are transferred from their mothers during gestation and that the transfer also continues after parturition via milk. Principal component analysis (PCA) showed that in pups, 4-OH-CB107 and 3'-OH-CB138 were negatively associated with FT4:FT3 and TT3:FT3 ratios, respectively. These relationships were confirmed by partial correlation analysis correcting for pup age. PCA suggested that 4'-OH-CB172 and 4-OH-CB187 were negatively associated with TT3 in mothers. However, this was not confirmed by correlation tests. Although statistical relationships should be interpreted with caution, the study indicates that young developing seals are more sensitive compared to adults with respect to TH-related effects of OH-PCBs.
    Aquatic toxicology (Amsterdam, Netherlands) 08/2011; 105(3-4):482-91. · 3.12 Impact Factor
  • Article: Highest clinical effectiveness of rituximab in autoantibody-positive patients with rheumatoid arthritis and in those for whom no more than one previous TNF antagonist has failed: pooled data from 10 European registries.
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    ABSTRACT: To assess the 6-month effectiveness of the first rituximab (RTX) course in rheumatoid arthritis (RA) and to identify possible predictors of response. 10 European registries submitted anonymised datasets (baseline, 3- and 6-month follow-up) from patients with RA who had started RTX, and datasets were pooled and analysed. Heterogeneity between countries was analysed by analysis of variance. Predictors of response were identified by logistic regression. 2019 patients were included (mean age/disease duration 53.8/12.1 years, 80.3% female, 85.6% rheumatoid factor (RF) positive and 76.8% (456/594 patients) anti-cyclic citrullinated peptide antibodies (anti-CCP) positive). For these patients an average of 2.7 disease-modifying antirheumatic drugs (DMARDs) (range 0-10) had failed, and RTX was given as the first biological agent in 36.6% of patients. There was significant heterogeneity between countries for several baseline characteristics, including the number of previous biological agents. Disease Activity Score based on 28 joint counts (DAS28) decreased from 5.8±1.4 at baseline to 4.2±1.4 at 6 months (p<0.0001) and 22.2%/42.5% achieved European League Against Rheumatism (EULAR) good/moderate response. Larger 6-month improvement in DAS28 was observed in RF-positive and anti-CCP-positive versus seronegative patients. The following predictors of EULAR good response at 6 months were identified in a multivariate analysis: anti-CCP positivity (OR=2.86, p=0.003), number of previous DMARDs (OR=0.84, p=0.06), ≤1 previous biological agents (OR=1.89, p=0.04), baseline DAS28 level (OR=0.74, p=0.003). In this large observational cohort of patients with RA treated with RTX, seropositive patients achieved significantly greater reductions in DAS28 at 6 months than seronegative patients. Effectiveness was best when RTX was used as the first biological agent or after failure of no more than one anti-tumour necrosis factor agent.
    Annals of the rheumatic diseases 05/2011; 70(9):1575-80. · 8.11 Impact Factor
  • Article: Accumulation and effects of natural mixtures of persistent organic pollutants (POP) in Zebrafish after two generations of exposure.
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    ABSTRACT: Effects of exposure to environmentally realistic mixtures of persistent organic pollutants (POP) harvested from aquatic ecosystems in Norway were studied in an in vivo zebrafish model. POP were extracted from burbot (Lota lota) liver from two separate lakes, Lake Losna and Lake Mjøsa, and exposed to zebrafish through the diet in a two-generation study. Effects on survival, growth, sex ratio, and timing of puberty were investigated. In addition, the biomarkers 7-ethoxyresorufin O-deethylase (EROD) and vitellogenin (Vtg) were measured. The ratios of contaminant levels in extracts collected from Lake Mjøsa:Lake Losna were 6, 10, and 270 for polychlorinated biphenyls (PCB), dichlorodiphenyltrichloroethanes (DDT), and polybrominated diphenyl ethers (PBDE), respectively. The concentration range of POP measured in zebrafish was lower than in burbot originating from Lake Mjøsa, but comparable to concentrations previously reported in humans and wildlife. The results showed that exposure to environmentally realistic mixtures of POP exerted a negative effect on survival of fish in both generations. The marked drop in survival during 9-20 days post fertilization (dpf) suggested that this period may be a critical window for development. In both generations an earlier onset of puberty was observed and a higher proportion of males than females was noted in exposed fish compared to controls. Suprising effects of exposure were found on body weight. In the first generation (F(0)), body weight was significantly higher in both exposure groups compared to controls, while in the next generation (F(1)) the same exposures were associated with a decrease in body weight. Zebrafish exposed to relatively low quantities of POP showed a significant induction of biomarkers (EROD and Vtg), while fish exposed to higher exposure doses did not demonstrate induction.
    Journal of Toxicology and Environmental Health Part A 01/2011; 74(7-9):407-23. · 1.83 Impact Factor
  • Article: Sleep problems are of higher priority for improvement for patients with ankylosing spondylitis than for patients with other inflammatory arthropathies.
    Annals of the rheumatic diseases 11/2010; 70(5):872-3. · 8.11 Impact Factor
  • Article: Ankylosing Spondylitis Disease Activity Score (ASDAS): defining cut-off values for disease activity states and improvement scores.
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    ABSTRACT: The Ankylosing Spondylitis Disease Activity Score (ASDAS) is a new composite index to assess disease activity in ankylosing spondylitis (AS). It fulfils important aspects of truth, feasibility and discrimination. Criteria for disease activity states and improvement scores are important for use in clinical practice, observational studies and clinical trials and so far have not been developed for the ASDAS. To determine clinically relevant cut-off values for disease activity states and improvement scores using the ASDAS. For the selection of cut-offs data from the Norwegian disease modifying antirheumatic drug (NOR-DMARD) registry, a cohort of patients with AS starting conventional or biological DMARDs, were used. Receiver operating characteristic analysis against several external criteria was performed and several approaches to determine the optimal cut-offs used. The final choice was made on clinical and statistical grounds, after debate and voting by Assessment of SpondyloArthritis international Society members. Crossvalidation was performed in NOR-DMARD and in Ankylosing Spondylitis Study for the Evaluation of Recombinant Infliximab Therapy, a database of patients with AS participating in a randomised placebo-controlled trial with a tumour necrosis factor blocker. Four disease activity states were chosen by consensus: inactive disease, moderate, high and very high disease activity. The three cut-offs selected to separate these states were: 1.3, 2.1 and 3.5 units. Selected cut-offs for improvement were: change ≥1.1 units for clinically important improvement and change ≥2.0 units for major improvement. Results of the crossvalidation strongly supported the cut-offs. Cut-off values for disease activity states and improvement using the ASDAS have been developed. They proved to have external validity and a good performance compared to existing criteria.
    Annals of the rheumatic diseases 11/2010; 70(1):47-53. · 8.11 Impact Factor

Institutions

  • 2009–2013
    • Diakonhjemmet Hospital (Norway)
      Oslo, Oslo, Norway
  • 2003–2011
    • Norwegian University of Science and Technology (NTNU)
      • Department of Biology
      Trondheim, Sor-Trondelag Fylke, Norway
  • 2010
    • Oslo University Hospital
      Oslo, Oslo, Norway
  • 2003–2006
    • Norwegian School of Veterinary Science
      • • Department of Production Animal Clinical Sciences
      • • Department of Reproduction and Forensic Medicine
      Oslo, Oslo, Norway
  • 2004–2005
    • National Veterinary Laboratory
      Franklin Lakes, NJ, USA