Olafur S Indridason

National University Hospital of Iceland, Reikiavik, Capital Region, Iceland

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Publications (69)260.31 Total impact

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    ABSTRACT: Background Adenine phosphoribosyltransferase (APRT) deficiency is a purine metabolism disorder causing kidney stones and chronic kidney disease (CKD). The course of nephrolithiasis and CKD has not been well characterized. The objective of this study was to examine long-term kidney outcomes in patients with APRT deficiency. Study Design An observational cohort study. Setting & Participants All patients enrolled in the APRT Deficiency Registry of the Rare Kidney Stone Consortium. Outcomes Kidney stones, acute kidney injury (AKI), stage of CKD, end-stage renal disease, estimated glomerular filtration rate (eGFR), and changes in eGFR. Measurements Serum creatinine and eGFR calculated using creatinine-based equations. Results Of 53 patients, 30 (57%) were females and median age at diagnosis was 37.0 (range, 0.6-67.9) years. Median duration of follow-up was 10.3 (range, 0.0-31.5) years. At diagnosis, kidney stones had developed in 29 (55%) patients and 20 (38%) had CKD stages 3 to 5, including 11 (21%) patients with stage 5. At latest follow-up, 33 (62%) patients had experienced kidney stones; 18 (34%), AKI; and 22 (42%), CKD stages 3 to 5. Of 14 (26%) patients with stage 5 CKD, 12 had initiated renal replacement therapy. Kidney stones recurred in 18 of 33 (55%) patients. The median eGFR slope was −0.38 (range, −21.99 to 1.42) mL/min/1.73 m2 per year in patients receiving treatment with an xanthine dehydrogenase inhibitor and −5.74 (range, −75.8 to −0.10) mL/min/1.73 m2 per year in those not treated prior to the development of stage 5 CKD (P = 0.001). Limitations Use of observational registry data. Conclusions Progressive CKD and AKI episodes are major features of APRT deficiency, whereas nephrolithiasis is the most common presentation. Advanced CKD without a history of kidney stones is more prevalent than previously reported. Our data suggest that timely therapy may retard CKD progression.
    No preview · Article · Dec 2015 · American Journal of Kidney Diseases
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    ABSTRACT: Aim: Acute kidney injury (AKI) is a common complication of medical and surgical interventions in hospitalized patients and associates with high mortality. Our aim was to examine renal recovery and long-term survival and time trends in AKI survival. Methods: Changes in serum creatinine (SCr) were used to define AKI in patients at Landspitali University Hospital in Iceland from 1993 to 2013. Renal recovery was defined as SCr < 1.5x baseline. Results: Out of 25,274 individuals who had their highest measured SCr during hospitalization and an available baseline SCr, 10,419 (41%) had AKI during hospitalization (H-AKI), 19%, 11% and 12% with Stage 1, 2 and 3, respectively. The incidence of H-AKI increased from 18.6 (95% CI, 14.7-22.5) to 29.9 (95% CI, 26.7-33.1) per 1000 admissions/year over the study period. Survival after H-AKI was 61% at 90-days and 51% at one year. Comparing H-AKI patients to propensity score matched individuals the Hazard ratio for death was 1.49 (1.36-1.62), 2.17 (1.95-2.41) and 2.95 (2.65-3.29) for Stage 1, 2 and 3, respectively. One-year survival of H-AKI patients improved from 47% in 1993-1997 to 57% in 2008-2013 and the adjusted hazard rate for mortality improved, compared to the first five-year period, 0.85 (0.81-0.89), 0.67 (0.64-0.71), and 0.57 (0.53-0.60) for each subsequent 5-year interval. Recovery of renal function was achieved in 88%, 58% and 44% of patients in Stages 1, 2 and 3, respectively, improving with time. Conclusions: AKI is an independent predictor of long-term mortality in hospitalized patients but there has been a marked improvement in survival and renal recovery over the past two decades. This article is protected by copyright. All rights reserved.
    No preview · Article · Dec 2015 · Nephrology
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    ABSTRACT: We found that age-related decline in bone mineral density (BMD) is more pronounced in women than in men, that lean mass was the most important determinant of BMD in all age groups in both sexes, and that different factors may be important for bone health of men and women and at different ages. Multiple factors may affect bone mineral density (BMD). Our objective was to identify the correlates of age-related differences in BMD among men and women. We performed a cross-sectional study involving 490 men and 517 women between the age of 29 and 87 years that were free of medication and diseases known to affect bone metabolism. BMD was measured at various sites using dual-energy X-ray absorptiometry, and factors possibly associated with skeletal status were assessed by direct measurements and a detailed questionnaire. BMD was lower with advancing age at all BMD measurement sites, the greatest difference being for the femoral neck where in women BMD was 37.5 % lower in the oldest compared to that in the youngest age group, but the difference was 22.9 % in men. Levels of free estradiol were sharply lower after age of 40 among women; free testosterone declined gradually with age among men but was not independently associated with BMD. Factors including lean mass, physical activity, ionized calcium, C-terminal telopeptide (CTX), serum sodium, free estradiol, and smoking explained a large fraction of difference in BMD in different age groups but to a varying degree in men and women. Lean mass was the strongest independent factor associated with BMD at all sites among men and women. Age-related decline in BMD is more pronounced in women than in men, but determinants of BMD are multiple and interrelated. Our study indicates that different factors may be important for bone health of men and women and at different ages.
    No preview · Article · Dec 2015 · Archives of Osteoporosis
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    ABSTRACT: Background Chronic kidney disease (CKD) is common in the elderly, but data are limited on the distribution of glomerular filtration rate (GFR) and albuminuria and the prevalence of CKD and related complications in this population. Methods A cross-sectional study of 3173 older Icelandic adults [42% men; mean (standard deviation, SD) age of 80 (5) years] was performed to examine the distribution of estimated glomerular filtration rate (eGFR) from creatinine and cystatin C, the albumin-to-creatinine ratio (ACR), and CKD-related metabolic complications (hyperparathyroidism, anemia, hypoalbuminemia, increased anion gap, acidosis, hyperphosphatemia and hyperkalemia). Results There was substantial variability in eGFR [mean (SD) 64 (18) mL/min/1.73 m2] and ACR [median (interquartile range) 8 (5, 17) mg/g]. The prevalence (95% confidence interval) of reduced eGFR (30 mg/g) and CKD (either reduced eGFR or albuminuria) was 40% (38–41), 14% (12–15) and 45% (43–47), respectively. The prevalence of complications was higher among those with versus without CKD: hyperparathyroidism (38 versus 15%), anemia (26 versus 14%), hypoalbuminemia (19 versus 13%), increased anion gap (9 versus 5%), acidosis (5 versus 1%); (P ≤ 0.02 for all), except hyperphosphatemia (1 versus 1%) and hyperkalemia (0% overall). Conclusions The burden of CKD and CKD-related complications is high among community dwelling elderly Icelandic adults. The wide range of eGFR and ACR suggests heterogeneity in processes leading to CKD and that factors beyond aging contribute to the development of CKD in the elderly.
    No preview · Article · Oct 2015 · Nephrology Dialysis Transplantation
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    ABSTRACT: Background Kidney stone disease has been associated with reduced kidney function and chronic kidney disease (CKD). The objective of the study was to examine kidney function, body mass index (BMI) and the prevalence of cardiovascular disease, hypertension and diabetes in recurrent kidney stone formers. Methods A cross-sectional, case-control study comparing measures of kidney function, BMI and comorbid conditions was conducted in 195 kidney stone patients aged 18 to 70 years with recurrent clinical stone events and 390 age- and gender-matched controls. Wilcoxon-Mann-Whitney, chi-square tests and analysis of covariance were used to compare serum creatinine (SCr) and estimated glomerular filtration rate (eGFR) between the groups. Results The median age of stone formers was 51 (range, 19–70) years and 108 (55 %) were males. Seventy patients (36 %) had experienced 2–4 clinical stone events, 41 (21 %) 5–10 episodes and 84 (43 %) more than 10. The median SCr was 75 (41–140) μmol/L in the stone formers and 64 (34–168) μmol/L in the control group (p < 0.001). The mean eGFR was 87 ± 20 and 104 ± 22 mL/min/1.73 m 2 in the stone formers and controls, respectively (p < 0.001). After adjustment for body size and comorbid conditions, the difference in SCr and eGFR between cases and controls remained highly significant (p < 0.001). The prevalence of CKD was 9.3 % among stone formers compared with 1.3 % in the control group (P < 0.001). Hypertension and diabetes were significantly more prevalent among the cases that also had higher BMI than controls. Conclusions Recurrent kidney stone formers have a significantly lower level of kidney function and a markedly higher prevalence of CKD than age- and gender-matched control subjects. The observed deleterious effect of kidney stones on kidney function appears to be independent of comorbid conditions.
    Full-text · Article · Aug 2015 · BMC Nephrology
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    ABSTRACT: Lifetime risk estimates of CKD can be used effectively in public education campaigns. This study sought to estimate lifetime risk of incident CKD stage 3 and higher in Iceland for people without CKD by the age of 45 years. This was a prospective cohort study with longitudinal creatinine measurements of residents in Reykjavik, Iceland, from 1967 to 2005. CKD was ascertained by two consecutive eGFR measurements <60 ml/min per 1.73 m(2), development of treated kidney failure, one eGFR<60 ml/min per 1.73 m(2) if the participant died before the next evaluation, or one eGFR<45 ml/min per 1.73 m(2) if it was the last eGFR. Mean follow-up was 25 (SD 10) years. Of the study participants, 727 (19%) developed the outcome and 942 (24%) died first. By age 85 years, the lifetime risks for 45-year-old women and men without prevalent CKD were 35.8% (95% confidence interval [95% CI], 32.7 to 38.9) and 21.3% (95% CI, 18.7 to 23.8), respectively. Risk was higher in individuals with a lower eGFR, hypertension, and a higher body mass index. Lifetime risk for higher stages of CKD 3b and 4 were less common than stage 3a; by age 85 years, the lifetime risks for CKD stages 3a, 3b, and 4 in women were 38.5% (95% CI, 25.8 to 51.1), 19.4% (95% CI, 8.9 to 29.9), and 3.6% (95% CI, 2.2 to 5.0), respectively. The lifetime risk of developing CKD stage 3 or higher is substantial, emphasizing the importance of strategies to prevent development of CKD throughout the course of life. Estimates are lower than reported using single estimates of GFR, emphasizing the importance of confirming estimates of reduced GFR in studies of CKD. Copyright © 2015 by the American Society of Nephrology.
    No preview · Article · Aug 2015 · Clinical Journal of the American Society of Nephrology
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    ABSTRACT: Kidney stone disease is a complex disorder with a strong genetic component. We conducted a genome-wide association study of 28.3 million sequence variants detected through whole-genome sequencing of 2,636 Icelanders that were imputed into 5,419 kidney stone cases, including 2,172 cases with a history of recurrent kidney stones, and 279,870 controls. We identify sequence variants associating with kidney stones at ALPL (rs1256328[T], odds ratio (OR)=1.21, P=5.8 × 10(-10)) and a suggestive association at CASR (rs7627468[A], OR=1.16, P=2.0 × 10(-8)). Focusing our analysis on coding sequence variants in 63 genes with preferential kidney expression we identify two rare missense variants SLC34A1 p.Tyr489Cys (OR=2.38, P=2.8 × 10(-5)) and TRPV5 p.Leu530Arg (OR=3.62, P=4.1 × 10(-5)) associating with recurrent kidney stones. We also observe associations of the identified kidney stone variants with biochemical traits in a large population set, indicating potential biological mechanism.
    Full-text · Article · Aug 2015 · Nature Communications
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    ABSTRACT: Chronic kidney disease (CKD) is common in the elderly, but the cause is often not identifiable. Some posit that age-related reductions in glomerular filtration rate (GFR) and increases in albuminuria are normal, whereas others suggest that they are a consequence of vascular disease. Cross-sectional analysis of a substudy of a prospective cohort. AGES (Age, Gene/Environment Susceptibility)-Reykjavik Study. Exposure to higher blood pressure in midlife. Measured GFR using plasma clearance of iohexol and urine albumin-creatinine ratio. GFR was measured in 805 participants with mean age in midlife and late life of 51.0±5.8 and 80.8±4.0 (SD) years, respectively. Mean measured GFR was 62.4±16.5mL/min/1.73m(2) and median albuminuria was 8.0 (IQR, 5.4-16.5) mg/g. Higher midlife systolic and diastolic blood pressures were associated with lower later-life GFRs. Associations persisted after adjustment. Higher midlife systolic and diastolic blood pressures were also associated with higher albumin-creatinine ratios, and associations remained significant even after adjustment. This is a study of survivors, and people who agreed to participate in this study were healthier than those who refused. Blood pressure may encompass effects of the other risk factors. Results may not be generalizable to populations of other races. We were not able to adjust for measured GFR or albuminuria at the midlife visit. Factors other than advanced age may account for the high prevalence of CKD in the elderly. Midlife factors are potential contributing factors to late-life kidney disease. Further studies are needed to identify and treat midlife modifiable factors to prevent the development of CKD. Copyright © 2015 National Kidney Foundation, Inc. All rights reserved.
    No preview · Article · May 2015 · American Journal of Kidney Diseases
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    ABSTRACT: Background Rapid fluctuations in factor VII during warfarin anticoagulation change the international normalised ratio (INR) but contribute little to the antithrombotic effect. We aimed to assess non-inferiority of anticoagulation stabilisation with a warfarin monitoring method affected only by factors II and X (Fiix-prothrombin time [Fiix-PT]) compared with standard PT-INR monitoring that includes factor VII measurement as well. Methods The Fiix trial was a single centre, double-blind, prospective, non-inferiority, randomised controlled clinical trial. Ambulatory adults on warfarin with an INR target of 2-3 managed by an anticoagulation dosing service using software-assisted dosing at the National University Hospital of Iceland, Reykjavik, Iceland, were eligible for inclusion in this study. We excluded patients undergoing electroconversion and nursing home residents. Patients were randomly assigned (1: 1) to either the Fiix-PT monitoring group or the PT monitoring group by block randomisation. A blinded research INR (R-INR) based on results of the respective test was reported to the dosing staff. Participants were contacted by a study nurse at 4-week intervals to elicit information about thromboembolism or bleeding otherwise unknown to the anticoagulation management centre. The primary efficacy outcome was a composite of objectively diagnosed non-fatal and fatal arterial or venous thromboembolism, including myocardial infarction and transient ischaemic attacks, assessed in all eligible patients who were randomised (intention-to-monitor population). The safety endpoint was major bleeding or other clinically relevant bleeding, assessed in the per-protocol population. We assumed a 3% annual thromboembolism incidence and a non-inferiority margin of 2.5%. This trial is registered with ClinicalTrials.gov, number NCT01565239. Findings Between March 1, 2012, and Feb 28, 2014, we enrolled 1156 patients. 573 patients were assigned to Fiix-PT and 575 to PT-INR monitoring after exclusion of four patients from each group for various reasons. Median follow-up was 1.7 years (IQR 1.1-1.9). During days 1-720, ten (1.2% per patient year) thromboembolic events occurred in the Fiix-PT group versus 19 (2.3% per patient year) in the PT group (relative risk [RR] 0.52, 95% CI 0.25-1.13; p(non-inferiority) < 0.0001). Major bleeding occurred in 17 of 571 patients in the Fiix group (2.2% per patient year) versus 20 of 573 patients in the PT group (2.5% per patient year; RR 0.85, 0.45-1.61; p(non-inferiority) = 0.0034). Anticoagulation stability was improved with Fiix-PT monitoring as manifested by fewer tests, fewer dose adjustments, increased time in range and less INR variability than reported with standard PT monitoring. Interpretation Monitoring of warfarin with Fiix-PT improved anticoagulation and dosing stability and was clinically non-inferior to PT monitoring. Results from this trial suggest that during vitamin K antagonist treatment INR monitoring could be replaced by Fiix-PT and that this would lead to at least a non-inferior clinical outcome compared with monitoring with PT-INR.
    Full-text · Article · May 2015
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    ABSTRACT: Current guidelines recommend reporting eGFR using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations unless other equations are more accurate, and recommend the combination of creatinine and cystatin C (eGFRcr-cys) as more accurate than either eGFRcr or eGFRcys alone. However, preferred equations and filtration markers in elderly individuals are debated. In 805 adults enrolled in the community-based Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study, we measured GFR (mGFR) using plasma clearance of iohexol, standardized creatinine and cystatin C, and eGFR using the CKD-EPI, Japanese, Berlin Initiative Study (BIS), and Caucasian and Asian pediatric and adult subjects (CAPA) equations. We evaluated equation performance using bias, precision, and two measures of accuracy. We first compared the Japanese, BIS, and CAPA equations with the CKD-EPI equations to determine the preferred equations, and then compared eGFRcr and eGFRcys with eGFRcr-cys using the preferred equations. Mean (SD) age was 80.3 (4.0) years. Median (25th, 75th) mGFR was 64 (52, 73) ml/min per 1.73 m(2), and the prevalence of decreased GFR was 39% (95% confidence interval, 35.8 to 42.5). Among 24 comparisons with the other equations, CKD-EPI equations performed better in 9, similar in 13, and worse in 2. Using the CKD-EPI equations, eGFRcr-cys performed better than eGFRcr in four metrics, better than eGFRcys in two metrics, and similar to eGFRcys in two metrics. In conclusion, neither the Japanese, BIS, nor CAPA equations were superior to the CKD-EPI equations in this cohort of community-dwelling elderly individuals. Using the CKD-EPI equations, eGFRcr-cys performed better than eGFRcr or eGFRcys. Copyright © 2014 by the American Society of Nephrology.
    Full-text · Article · Dec 2014 · Journal of the American Society of Nephrology
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    ABSTRACT: Chronic kidney disease (CKD) is a complex disorder with a strong genetic component. A number of common sequence variants have been found to associate with serum creatinine (SCr), estimated glomerular filtration rate (eGFR) and/or CKD. We imputed 24 million single-nucleotide polymorphisms and insertions/deletions identified by whole-genome sequencing of 2230 Icelanders into 81 656 chip-typed individuals and 112 630 relatives of genotyped individuals over the age of 18 with SCr measurements. The large set of sequenced individuals allowed accurate imputation of variants to a minor allele frequency (MAF) of 0.1%. We tested the imputed variants for association with SCr. In addition to replicating established loci, we discovered missense and loss-of-function variants associating with SCr in three solute carriers (SLC6A19, SLC25A45 and SLC47A1) and two E3 ubiquitin ligases (RNF186 and RNF128). All the variants are within coding sequences and all but one are rare (MAF <2%) with SCr effects between 0.085 and 0.129 standard deviations. These rare variants have a larger effect on SCr than previously reported common variants, explaining 0.5% of the variability of SCr in Icelanders in addition to the 1% already accounted for. We tested the five variants associating with SCr for association with CKD in an Icelandic sample of 15 594 cases and 291 428 controls. Three of the variants also associated with CKD. These variants may either affect kidney function or creatinine synthesis and excretion. Of note were four mutations in SLC6A19 that associate with reduced SCr, three of which have been shown to cause Hartnup disease. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected] /* */
    No preview · Article · Jul 2014 · Human Molecular Genetics
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    ABSTRACT: Introduction: The Icelandic health care system ranks favourably in international comparison but patients' experience of interaction with the health service has not been well studied. The goal of this study was to examine the satisfaction of patients admitted to the Acute Cardiac Unit (ACU) at Landspitali - The National University Hospital of Iceland. Methods: A questionnaire based on the Patient Satisfaction Questionnaire III was mailed to patients admitted to the ACU between 1 January and 29 February 2012. Questions were presented as statements and participants asked to respond how strongly on a scale from 1 to 5 they agreed or disagreed with each statement. Data analysis was performed using descriptive statistics, Cronbach´s alpha for internal consistency of scales and principal components analysis, Wilcoxon-Mann-Whitney and Kruskal-Wallis tests for comparison of groups and Pearson and Spearman correlation coefficients for correlation between variables. Results: The questionnaire was mailed to 485 individuals of whom 275 (57%) responded. The median age of the participants was 62 (range, 19-95) years and 132 (48%) were women. Internal consistency of the scales was mostly high (Cronbach's alpha 0.62-0.91) and principal components analysis revealed one main factor. The mean score of the questionnaire was 6.8 ±1.0 and 91%, and 86% of the participants were pleased with their interaction with physicians and nurses, respectively. Similarly, 88% were pleased with the care they recieved but 25% felt they received insufficient explanations of their symptoms or that follow-up care was lacking. Conclusion: Patients of the ACU generally appear to be satisfied with their care. However, our results suggest that improvement is needed in several areas, including information provided at discharge and follow-up care.
    No preview · Article · Jun 2014 · Laeknabladid
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    Olof Viktorsdottir · Olafur Skuli Indridason · Runolfur Palsson
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    ABSTRACT: Rapid correction of severe hyponatremia can result in osmotic demyelination syndrome. Patients with severe hyponatremia and renal failure requiring dialysis pose a therapeutic challenge since the use of conventional intermittent hemodialysis will result in a rapid correction of the serum sodium level. We report the case of a 52-year-old woman with extreme hyponatremia and severe acute kidney injury, who was successfully treated with continuous venovenous hemodialysis using a modified dialysate solution with a low sodium concentration that was adjusted on a daily basis. © 2013 S. Karger AG, Basel.
    Full-text · Article · Dec 2013 · Blood Purification
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    ABSTRACT: Introduction: Acute kidney injury (AKI) is a common problem in hospitalized patients, requiring extensive treatment and carries a high mortality rate. This study was designed to assess the epidemiology of AKI, and risk factors and outcome of patients with severe AKI in a tertiary care university hospital in Iceland. Material and methods: All adult patients with measured serum creatinine (SCr) in Landspitali University Hospital from January 2008 to December 2011, who had a measured baseline SCr in the preceeding six months, were included. Patients were categorized according to the RIFLE-criteria into risk (stage 1), injury (stage 2) and failure (stage 3) groups based on their highest SCr, using the lowest SCr in the previous six months as baseline. Results: A total of 17,693 individuals (out of 74,960) had a baseline SCr and their data were used for analysis. AKI occurred in 3,686 (21%) with 12%, 5% and 4% of stage 1, 2 and 3, respectively. There were more females in stage 1 and stage 2 and more males in stage 3 (p< 0.001). Contributing causes for AKI in patients with stage 3 AKI were surgery (22%), circulatory shock (23%), sepsis (14%), cardiovascular insult (32%), respiratory failure (27%), bleeding (10%), trauma (7%) and AKI associated drugs (61%). Dialysis was required in 11% and in 0.7% for longer than 30 days but none > 90 days. One year survival was 52%. Conclusions: Acute kidney injury is common in Iceland and the prognosis of those with severe AKI is dismal. Majority of those patients were taking drugs that increase risk of AKI, providing a target for preventive measures.
    Full-text · Article · Nov 2013 · Laeknabladid
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    ABSTRACT: Background/objectives: Randomised controlled trials (RCTs) evaluating the effect of fish oil supplementation on postoperative atrial fibrillation (POAF) following cardiac surgery have produced mixed results. In this study, we examined relationships between levels of red blood cell (RBC) n-3 long-chain polyunsaturated fatty acids (LC-PUFAs) and the incidence of POAF. Subjects/methods: We used combined data (n=355) from RCTs conducted in Australia and Iceland. The primary end point was defined as POAF lasting >10 min in the first 6 days following surgery. The odds ratios (ORs) for POAF were compared between quintiles of preoperative RBC n-3 LC-PUFA levels by multivariable logistic regression. Results: Subjects with RBC docosahexaenoic acid (DHA) in the fourth quintile, comprising a RBC DHA range of 7.0-7.9%, had the lowest incidence of POAF. Subjects in the lowest and highest quintiles had significantly higher risk of developing POAF compared with those in the fourth quintile (OR=2.36: 95% CI; 1.07-5.24 and OR=2.45: 95% CI; 1.16-5.17, respectively). There was no association between RBC eicosapentaenoic acid levels and POAF incidence. Conclusions: The results suggest a 'U-shaped' relationship between RBC DHA levels and POAF incidence. The possibility of increased risk of POAF at high levels of DHA suggests an upper limit for n-3 LC-PUFAs in certain conditions.
    Full-text · Article · Oct 2013 · European journal of clinical nutrition
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    Full-text · Article · Oct 2013 · European Journal of Clinical Investigation
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    ABSTRACT: Limited data exist on the comparison of blood pressure (BP) measurements using aneroid and oscillometric devices. The purpose of the study was to investigate the difference in BP obtained using oscillometric and aneroid BP monitors in 9- to 10-year-old children. A total of 979 children were divided into group O, which underwent two oscillometric BP readings followed by two aneroid readings, and group A, which had BP measured in the reverse order. No significant difference was found between the mean (±standard deviation) of the two systolic BP readings obtained using the oscillometric and aneroid devices (111.5±8.6 vs 111.3±8.1 mm Hg; P=.39), whereas the mean diastolic BP was lower with the oscillometric monitor (61.5±8.0 vs 64.5±6.8 mm Hg; P<.001). A significant downward trend in BP was observed with each consecutive measurement, and agreement between the two monitors was limited. Multiple BP measurements are, therefore, recommended before the diagnosis of elevated BP or hypertension is made with either method.
    Full-text · Article · Sep 2013 · Journal of Clinical Hypertension
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    ABSTRACT: Objectives: Postoperative atrial fibrillation (POAF) has been associated with an inflammatory response to the surgical procedure. n-3 long-chain polyunsaturated fatty acids (LC-PUFA) have been proposed for the prevention of POAF. We investigated the relationship between the plasma concentration of inflammatory mediators, levels of n-3 LC-PUFA in red blood cell (RBC) membrane lipids, and the risk of POAF after coronary artery bypass grafting (CABG). Methods: A total of 125 patients who underwent CABG were studied. Inflammatory mediators in plasma and the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in RBC membranes were assessed. Results: Sixty-two patients (49.6%) developed POAF. The POAF group had higher RBC levels of total n-3 LC-PUFA and DHA than did patients remaining in sinus rhythm (p < 0.05). Of the inflammatory mediators, only postoperative interleukin-6 levels differed, being higher in the POAF group (p < 0.05). Inflammatory mediators were not independent predictors of POAF by multivariable logistic regression analysis. Higher levels of DHA and total n-3 LC-PUFA in RBC membranes, measured immediately prior to CABG and on postoperative day 3, were linearly associated with an increased risk of POAF (p < 0.05). Conclusions: Our findings suggest that inflammatory mediators are not associated with the occurrence of POAF. Interestingly, high n-3 LC-PUFA levels in RBC membranes appear to increase the risk of POAF.
    Full-text · Article · Aug 2013 · Cardiology
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    ABSTRACT: Open heart surgery is associated with a systemic inflammatory response. The n-3 long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and the n-6 LC-PUFA arachidonic acid (AA) may contribute to modulation of the inflammatory response. We investigated whether the preoperative levels of EPA, DHA and AA in plasma phospholipids (PL) and red blood cell (RBC) membrane lipids in patients (n=168) undergoing open heart surgery were associated with changes in the plasma concentration of selected inflammatory mediators in the immediate postoperative period. The postoperative concentration of TNF-β was lower (P<0.05) and those of hs-CRP, IL-6, IL-8, IL-18 and IL-10 higher (P<0.05) than the respective preoperative concentrations. We observed that the preoperative levels of EPA and AA in plasma PL and RBC membrane lipids were associated with changes in the concentration of pro-inflammatory and anti-inflammatory mediators, suggesting a complex role in the postoperative inflammatory process.
    Full-text · Article · Aug 2013 · Prostaglandins Leukotrienes and Essential Fatty Acids
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    ABSTRACT: Background: Differences in body composition may lead to imprecision in estimates of glomerular filtration rate (eGFR) derived from serum creatinine. Our aims were to examine the relationship between eGFR and anthropometric and body composition measures and handgrip strength. Methods: We analyzed data from a cross-sectional study comprising 1,630 randomly selected community-dwelling adults. The Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations were used to calculate eGFR from IMDS-standardized serum creatinine. Body mass index and body surface area were calculated from measured height and weight. Body composition was determined by dual-energy x-ray absorptiometry, handgrip strength measured by a hand-held dynamometer. Regression analysis was used to examine the association between eGFR and other factors. Results: In women, eGFR determined by the MDRD equation was inversely associated with height (β = -0.08; p = 0.012), lean mass percentage (β = -0.06; p = 0.047) and handgrip strength (β = -0.15; p < 0.001) and eGFR calculated using the CKD-EPI equation was inversely associated with handgrip strength (β = -0.08; p = 0.001). In men, there was an inverse association between eGFR by the MDRD equation and lean mass percentage (β = -0.10; p = 0.013) and handgrip strength (β = -0.12; p = 0.022) and between eGFR by the CKD-EPI equation and lean mass percentage (β = -0.07; p = 0.018). The R(2) for these variables was <0.02. Conclusions: The inverse relationship between eGFR and measures of lean mass percentage and handgrip strength suggests that incorporation of these variables might improve eGFR prediction from serum creatinine in the general population. This effect appears to be small however and needs to be examined in studies that include measured GFR.
    Full-text · Article · Jun 2013 · Nephron Clinical Practice

Publication Stats

1k Citations
260.31 Total Impact Points

Institutions

  • 2001-2015
    • National University Hospital of Iceland
      • • Department of Medicine
      • • Childrens hospital
      Reikiavik, Capital Region, Iceland
  • 2009-2010
    • Reykjavik University
      Reikiavik, Capital Region, Iceland
  • 2003-2010
    • University of Iceland
      • Faculty of Medicine
      Reikiavik, Capital Region, Iceland