Omega-3 Blood Levels and Stroke Risk: A Pooled and Harmonized Analysis of 183 291 Participants From 29 Prospective Studies.

BACKGROUND: The effect of marine omega-3 PUFAs on risk of stroke remains unclear. METHODS: We investigated the associations between circulating and tissue omega-3 PUFA levels and incident stroke (total, ischemic, and hemorrhagic) in 29 international prospective cohorts. Each site conducted a de novo individual-level analysis using a prespecified analytical protocol with defined exposures, covariates, analytical methods, and outcomes; the harmonized data from the studies were then centrally pooled. Multivariable-adjusted HRs and 95% CIs across omega-3 PUFA quintiles were computed for each stroke outcome. RESULTS: Among 183 291 study participants, there were 10 561 total strokes, 8220 ischemic strokes, and 1142 hemorrhagic strokes recorded over a median of 14.3 years follow-up. For eicosapentaenoic acid, comparing quintile 5 (Q5, highest) with quintile 1 (Q1, lowest), total stroke incidence was 17% lower (HR, 0.83 [CI, 0.76-0.91]; P<0.0001), and ischemic stroke was 18% lower (HR, 0.82 [CI, 0.74-0.91]; P<0.0001). For docosahexaenoic acid, comparing Q5 with Q1, there was a 12% lower incidence of total stroke (HR, 0.88 [CI, 0.81-0.96]; P=0.0001) and a 14% lower incidence of ischemic stroke (HR, 0.86 [CI, 0.78-0.95]; P=0.0001). Neither eicosapentaenoic acid nor docosahexaenoic acid was associated with a risk for hemorrhagic stroke. These associations were not modified by either baseline history of AF or prevalent CVD. CONCLUSIONS: Higher omega-3 PUFA levels are associated with lower risks of total and ischemic stroke but have no association with hemorrhagic stroke.

Adipose tissue n-3/n-6 fatty acids ratios versus n-3 fatty acids fractions as predictors of myocardial infarction.

BACKGROUND: Tissue levels of n-3 polyunsaturated fatty acids (PUFAs) have been inversely related with risk of myocardial infarction (MI). Whether ratios of n-3 to n-6 PUFAs, reflecting both dietary intake of n-3 PUFAs and competing n-6 PUFAs, are better predictors of future MI than n-3 PUFA fractions is unclear. We aimed at investigating whether such ratios in adipose tissue better predict MI than n-3 PUFA fractions. METHODS: Subcutaneous adipose tissue biopsies were obtained in a random sample (n = 3,500) of the Diet, Cancer and Health cohort (n = 57,053). Adipose tissue content of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), arachidonic acid (AA) and linoleic acid was determined using gas chromatography. Fractions of selected n-3 PUFAs and n-3/n-6 PUFA ratios were correlated to the 15-year occurrence of MI in a case-cohort design. RESULTS: A total of 2,406 participants experienced an MI during follow-up. Adipose tissue total marine n-3 PUFAs, EPA+DHA, EPA, EPA/AA, DHA/AA and (EPA + DPA + DHA)/AA were all inversely associated with risk of incident MI. Evaluating the predictive power (Harrel's C-index) of the selected metrics, fractions of marine n-3 PUFAs and ratios of EPA/AA, DHA/AA, (EPA + DHA)/AA and (EPA + DPA + DHA)/AA all refined risk prediction over age and sex alone. At multivariable analyses, however, the above ratios were the only metrics providing additional risk prediction. Differences in ratios were related to differences in food intake. CONCLUSIONS: Both adipose tissue n-3 PUFAs fractions and ratios of n-3 PUFAs/AA were associated with a lower occurrence of MI, but ratios provided superior risk prediction. Dietary strategies affecting n-3/n-6 PUFA ratios should be further investigated for prediction of MI with dietary interventions at the population level and in intervention studies.

Intake of marine n-3 polyunsaturated fatty acids and risk of hemorrhagic stroke and its subtypes: a Danish follow-up study.

BACKGROUND: A diet rich in marine n-3 polyunsaturated fatty acids (PUFAs) may lower the risk of coronary heart disease and ischemic stroke. However, the association between intake of marine n-3 PUFAs and risk of hemorrhagic stroke has only been sparsely explored. We aimed to investigate the associations between intake of the major marine n-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and their sum in relation to incident hemorrhagic stroke and its subtypes intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). METHODS: We analyzed data from the Danish Diet, Cancer and Health Cohort, which was established between 1993 and 1997. Information on dietary intake of marine n-3 PUFAs was obtained through a validated food frequency questionnaire. Potential hemorrhagic stroke cases were identified by linkage to the Danish National Patient Register and subsequently validated. Hazard ratios obtained by Cox proportional hazard regression were used as measures of association. RESULTS: A total of 394 subjects among 55,519 individuals developed hemorrhagic stroke during a median follow-up period of 13.5 years. In multivariable analyses including adjustment for established risk factors, we observed weak and statistically non-significant indications of inverse associations between intake of EPA, DHA, and EPA + DHA and the rate of incident hemorrhagic stroke. In analyses of hemorrhagic stroke subtypes, we found indications of lower rates of ICH among participants in the highest quartile of EPA, DHA, and EPA + DHA compared with those in the lowest quartile, and indications of lower rates of SAH in the highest quartile of EPA intake compared to the lowest quartile but the findings were statistically non-significant. CONCLUSIONS: Indications of inverse statistically non-significant associations were found between EPA, DHA, and EPA + DHA and hemorrhagic stroke.

Effects of n-3 Fatty Acid Supplements in Elderly Patients After Myocardial Infarction: A Randomized, Controlled Trial.

BACKGROUND: High intake of marine n-3 polyunsaturated fatty acids (PUFA) has been associated with reduced risk of cardiovascular events; however, this has not been confirmed in patients with a recent acute myocardial infarction (AMI). Elderly patients are at particularly increased cardiovascular risk after myocardial infarction, but few trials address this group specifically. Omega-3 fatty acids hold the potential to reduce cardiovascular events with limited adverse effects in this vulnerable group. The hypothesis was that daily addition of 1.8g n-3 PUFA to standard of care secondary prophylaxis in elderly patients who have survived an AMI would reduce the risk of subsequent cardiovascular events during 2 years follow-up. METHODS: The OMEMI trial (Omega-3 Fatty acids in Elderly with Myocardial Infarction) is an investigator-initiated, multicenter, randomized clinical trial adding 1.8 g n-3 PUFA (930 mg eicosapentaenoic acid and 660 mg docosohexaenoic acid) versus placebo (corn oil) daily to standard of care in patients aged 70 to 82 years with recent (2-8 weeks) AMI. The primary endpoint was a composite of nonfatal AMI, unscheduled revascularization, stroke, all-cause death, heart failure hospitalization after 2 years. The secondary outcome was new atrial fibrillation. The safety outcome was major bleeding. Serum fatty acids were measured as biomarkers of adherence. RESULTS: In total, 1027 patients were randomized. Follow-up data were available for 1014 patients who were included in the intention-to-treat analysis. Mean±SD age was 75±3.6 years, 294 (29%) were female, and mean triglycerides were 111.4±61.9 mg/dL. The primary endpoint occurred in 108 (21.4%) patients on n-3 PUFA versus 102 (20.0%) on placebo (hazard ratio, 1.08 [95% CI, 0.82-1.41]; P=0.60). The secondary endpoint occurred in 28 (7.2%) patients on n-3 PUFA versus 15 (4.0%) on placebo (1.84 [0.98-3.45]; P=0.06). Median changes in eicosapentaenoic acid and docosahexaenoic acid were +87% and +16% for n-3 PUFA versus -13% and -8% for placebo. Major bleeding occurred in 54 (10.7%) and 56 (11.0%) in the n-3 PUFA and placebo groups, respectively (P=0.87). Similar results were found in per-protocol analysis (n=893). CONCLUSIONS: We could not detect reduction in clinical events in our elderly patients with recent AMI who were treated with 1.8 g n-3 PUFAs daily for 2 years. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01841944.

Omega-3 fatty acids in adipose tissue and risk of atrial fibrillation.

BACKGROUND: The aim of the present study was to examine the relation between adipose tissue content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the risk of incident atrial fibrillation (AF). METHODS: In this case-cohort study based on data from the Danish Diet, Cancer and Health cohort, a total of 5255 incident cases of AF was identified during 16.9 years of follow-up. Adipose tissue biopsies collected at baseline from all cases and from a randomly drawn subcohort of 3440 participants were determined by gas chromatography. Data were analysed using weighted Cox regression. RESULTS: Data were available for 4741 incident cases of AF (2920 men and 1821 women). Participants in the highest vs. the lowest quintile of EPA experienced a 45% lower risk of AF (men HR 0.55 (95% CI 0.41-0.69); women HR 0.55 (0.41-0.72)). For DHA, no clear association was found in men, whereas in women, participants in the highest quintile of DHA in adipose tissue had a 30% lower risk of incident AF (HR 0.70 (0.54-0.91)) compared to participants in the lowest quintile. CONCLUSIONS: A monotonous inverse association was found for the content of EPA in adipose tissue and risk of AF in both men and women. The content of DHA was inversely associated with the risk of AF in women, whereas no clear association was found for men.

Are fatty acids associated with disease activity and biomarkers in patients with psoriatic arthritis? Data from a multicenter clinical trial.

The pathogenesis of psoriatic arthritis (PsA) involves inflammation and bone and soft tissue turnover. Dietary fatty acids have previously been associated with pro-inflammatory effects induced by saturated fatty acids (SFA) and anti-inflammatory effects achieved by at least some polyunsaturated fatty acids (PUFA). The aim of the study was to investigate the correlations between the content of fatty acids in granulocytes and clinical and biochemical markers of PsA. A total of 140 patients with PsA were included. Skin and joint disease activity were assessed. Fatty acid composition in granulocytes was determined by gas chromatography. Competitive enzyme-linked immunosorbent assays were used to assess bone and soft tissue turnover. The content of SFA, n-6 PUFA or n-3 PUFA in granulocytes was not associated with disease activity. Marine n-3 PUFA was significantly positively correlated with collagen degradation. In contrast, n-6 PUFA was significantly positively correlated with collagen formation and negatively correlated with collagen degradation. However, the correlations were all weak. No association was found between the content of fatty acids in granulocytes and disease activity in this population of patients with PsA. The correlation between fatty acids and biomarkers of bone and soft tissue turnover needs further investigation.

Linoleic acid in adipose tissue and the risk of myocardial infarction: a case-cohort study.

PURPOSE: We investigated risk of myocardial infarction (MI) associated with the content of linoleic acid (LA) in adipose tissue, a biomarker of long-term dietary intake of LA and a marker of endogenous LA exposure. METHODS: Between 1993 and 1997, 57,053 middle-aged subjects were included in the Danish Diet, Cancer and Health cohort. We performed a case-cohort study that included a random sample of the full cohort (n = 3167) and all incident MI cases appearing during 16 years of follow-up (n = 2819). Information on incident MI cases was obtained by linkage with Danish nationwide registries. Adipose tissue biopsies were taken from the buttocks of the participants, and their fatty acid composition was determined using gas chromatography. HRs (hazard ratios) with 95% confidence intervals (CIs) were used to describe the associations between content of LA in adipose tissue and the risk of MI. HRs were calculated using weighted Cox proportional hazards regression with robust variance. RESULTS: After adjustment for established risk factors of MI, adipose tissue content of LA was not associated with the risk of MI in men and women combined (quintiles 5 versus 1, HR, 1.03 (95% CI, 0.85-1.25), P-trend = 0.970) or in men and women separately (quintiles 5 versus 1, HR, 1.05 (95% CI, 0.83-1.33), P-trend = 0.871 and quintiles 5 versus 1, HR, 0.99 (95% CI 0.72-1.37), P-trend = 0.928, respectively). Investigating the association between LA and MI with a shorter, 5- or 10-year duration of follow-up provided similar results. CONCLUSION: Content of LA in adipose tissue was not associated with the risk of MI.

Substitutions between potatoes and other vegetables and risk of ischemic stroke.

PURPOSE: Intake of vegetables has been associated with a lower risk of ischemic stroke in observational studies controlling for total energy intake. However, adjustment for energy intake introduces a substitution aspect, which affects the interpretation of the results. We investigated replacement of potatoes with other vegetables, substitutions between vegetable subgroups, and risk of ischemic stroke and ischemic stroke subtypes. METHODS: The Danish Diet, Cancer and Health cohort included 57,053 participants aged 50-64 years at recruitment in 1993-1997. Diet was assessed from a validated 192-item semi-quantitative food frequency questionnaire. We calculated hazard ratios (HR) with 95% confidence intervals (CI) for the incidence of ischemic stroke using Cox proportional hazard regression. RESULTS: During 13.5 years of follow-up, 1879 cases of ischemic stroke were identified including 319 cases of large-artery atherosclerosis and 844 cases of small-vessel occlusion. The adjusted HR for total ischemic stroke associated with food substitutions of equal amounts (500 g/week) was 0.86 (95% CI 0.76, 0.97) for replacement of potatoes with fruiting vegetables and 0.92 (95% CI 0.84, 1.02) for replacement of potatoes with other root vegetables. The HR for replacing potatoes with the sum of other vegetables was 0.95 (95% CI 0.90, 1.00). Substitution of cabbage for either potatoes, fruiting vegetables or other root vegetables was associated with a statistically non-significant higher risk of ischemic stroke. The patterns of associations were similar for ischemic stroke subtypes and for equivalent substitutions using isocaloric amounts. CONCLUSION: Replacing potatoes with fruiting vegetables was associated with a lower risk of ischemic stroke.

Effect of n-3 PUFA on extracellular matrix protein turnover in patients with psoriatic arthritis: a randomized, double-blind, placebo-controlled trial.

Psoriatic arthritis (PsA) is a chronic inflammatory disease characterized by involvement of skin, axial and peripheral skeleton. An altered balance between extracellular matrix (ECM) formation and breakdown is a key event in PsA, and changes in ECM protein metabolites may provide insight to tissue changes. Dietary fish oils (n-3 PUFA) might affect the inflammation driven tissue turnover. The aim was to evaluate ECM metabolites in patients with PsA compared to healthy individuals and investigate the effects of n-3 PUFA. The 24-week randomized, double-blind, placebo-controlled trial of PUFA included 142 patients with PsA. Fifty-seven healthy individuals were included for comparison. This study is a sub-study investigating biomarkers of tissue remodelling as secondary outcomes. Serum samples at baseline and 24 weeks and healthy individuals were obtained, while a panel of ECM metabolites reflecting bone and soft tissue turnover were measured by ELISAs: PRO-C1, PRO-C3, PRO-C4, C1M, C3M, C4M, CTX-I and Osteocalcin (OC). C1M, PRO-C3, PRO-C4 and C4M was found to be elevated in PsA patients compared to the healthy individuals (from 56 to 792%, all p < 0.0001), where no differences were found for OC, CTX-I, PRO-C1 and C3M. PRO-C3 was increased by 7% in patients receiving n-3 PUFA after 24 weeks compared to baseline levels (p = 0.002). None of the other biomarkers was changed with n-3 PUFA treatment. This indicates that tissue turnover is increased in PsA patients compared to healthy individuals, while n-3 PUFA treatment for 24 weeks did not have an effect on tissue turnover. Trial registration NCT01818804. Registered 27 March 2013-Completed 18 February 2016. https://clinicaltrials.gov/ct2/show/NCT01818804?term=NCT01818804&rank=1.

Arrhythmias in Patients on Maintenance Dialysis: A Cross-sectional Study.

RATIONALE & OBJECTIVE: Patients with kidney failure treated with maintenance dialysis experience a high rate of mortality, in part due to sudden cardiac death caused by arrhythmias. The prevalence of arrhythmias, including the subset that are clinically significant, is not well known. This study sought to estimate the prevalence of arrhythmias, characterize the pattern of arrhythmic events in relation to dialysis treatments, and identify associated clinical characteristics. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: 152 patients with kidney failure treated with maintenance dialysis in Denmark. EXPOSURES: Dialysis treatment; clinical characteristics; cardiac output and preload defined using echocardiography. OUTCOMES: Prevalence and pattern of arrhythmias on 48-hour Holter monitoring; odds ratios for arrhythmias. ANALYTICAL APPROACH: Descriptive analysis of the prevalence of arrhythmias. Pattern of arrhythmias described using a repeated-measures negative binomial regression model. Associations between clinical characteristics and echocardiographic findings with arrhythmias were assessed using logistic regression. RESULTS: Among the 152 patients studied, 83.6% were treated with in-center dialysis; 10.5%, with home hemodialysis; and 5.9%, with peritoneal dialysis. Premature atrial and ventricular complexes were seen in nearly all patients and 41% had paroxysmal supraventricular tachycardia. Clinically significant arrhythmias included persistent atrial fibrillation observed among 8.6% of patients, paroxysmal atrial fibrillation among 3.9%, nonsustained ventricular tachycardia among 19.7%, bradycardia among 4.6%, advanced second-degree atrioventricular block among 1.3%, and third-degree atrioventricular block among 2.6%. Premature ventricular complexes were more common on dialysis days, while tachyarrhythmias were more often observed during dialysis and in the immediate postdialytic period. Older age (OR per 10 years older, 1.53; 95% CI, 1.15-2.03; P=0.003), elevated preload (OR, 4.02; 95% CI, 1.05-15.35; P=0.04), and lower cardiac output (OR per 1L/min greater, 0.66; 95% CI, 0.44-1.00; P=0.05) were independently associated with clinically significant arrhythmias. LIMITATIONS: Arrhythmia monitoring limited to 48 hours; small sample size; heterogeneous nature of the population, risk for residual confounding. CONCLUSIONS: Arrhythmias, including clinically significant abnormal rhythms, were common. Tachyarrhythmias were more frequent during dialysis and the immediate postdialytic period. The relevance of these findings to clinical outcomes requires additional study.

Plasma marine n-3 polyunsaturated fatty acids and cardiovascular risk factors: data from the ACE 1950 study.

PURPOSE: A high intake of marine n-3 polyunsaturated fatty acids (PUFAs) might improve cardiovascular (CV) health. We conducted a cross-sectional study to investigate associations between plasma phospholipid levels of marine n-3 PUFAs and CV risk factors, educational level, physical activity and smoking habits. METHODS: A total of 3706 individuals from a general population, all born in 1950 and residing in Akershus County, Norway, were included in this study. The main statistical approach was multivariable adjusted linear regression. RESULTS: Plasma marine n-3 PUFA levels ranged from 2.7 to 20.3 wt%, with a median level of 7.7 wt% (interquartile range 4.3-11.1 wt%). High levels of plasma marine n-3 PUFAs were associated with lower serum triglycerides [Standardized regression coefficient (Std.ß-coeff.) - 0.14, p < 0.001], body mass index (Std. ß-coeff. -0.08, p < 0.001), serum creatinine (Std. ß-coeff. -0.03, p = 0.05), C-reactive protein levels (Std. ß-coeff. - 0.03, p = 0.04), higher levels of serum high-density lipoprotein cholesterol (Std. ß-coeff. 0.08, p < 0.001) and low-density lipoprotein cholesterol (Std. ß-coeff. 0.04, p = 0.003). High levels of plasma marine n-3 PUFAs were also associated with lower glycated hemoglobin (Std. ß-coeff. - 0.04, p = 0.01), however, only in individuals without diabetes. We found no associations between plasma marine n-3 PUFA levels and fasting plasma glucose or carotid intima-media thickness. High levels of plasma marine n-3 PUFAs were associated with higher educational level, more physical activity and lower prevalence of smoking. CONCLUSION: In this cross-sectional study of Norwegian individuals born in 1950, high levels of plasma marine n-3 PUFAs were favourably associated with several CV risk factors, suggesting that fish consumption might improve CV health.

Adipose tissue fatty acids present in dairy fat and risk of stroke: the Danish Diet, Cancer and Health cohort.

PURPOSE: The role of dairy fat for the risk of stroke is not yet clear. Adipose tissue reflects long-term fatty acid intake and metabolism. We, therefore, investigated associations for percentages of adipose tissue fatty acids, for which dairy products are a major source (12:0, 14:0, 14:1 cis-9, 15:0, 17:0, 18:1 trans-11 and 18:2 cis-9, trans-11), with incident total stroke and stroke subtypes. METHODS: We conducted a case-cohort study within the Danish Diet, Cancer and Health cohort, including all incident stroke cases (n = 2108) and a random sample of the total cohort (n = 3186). The fatty acid composition of adipose tissue biopsies was determined by gas chromatography and specific fatty acids were expressed as percentage of total fatty acids. Stroke cases were identified in the Danish National Patient Registry and the diagnoses were individually verified. RESULTS: We recorded 2108 stroke cases of which 1745 were ischemic, 249 were intracerebral hemorrhages and 102 were subarachnoid hemorrhages. We observed a lower rate of ischemic stroke for a higher adipose tissue percentage of 12:0, 14:0, 15:0, 17:0, 18:1 trans-11 and 18:2 cis-9, trans-11. Adipose tissue percentages of 15:0 and 18:1 trans-11 were also inversely associated with intracerebral hemorrhage, whereas no associations between the adipose tissue fatty acids and subarachnoid hemorrhage were observed. No associations between 14:1 cis-9 and ischemic or hemorrhagic stroke were found. CONCLUSIONS: Our results suggest that a larger percentage in adipose tissue of fatty acids for which dairy products are a major source is associated with a lower rate of ischemic stroke.

Substitution of poultry and red meat with fish and the risk of peripheral arterial disease: a Danish cohort study.

PURPOSE: The aims of this study were to examine associations between substitutions of poultry and red meat intake with fish (total, lean or fatty) and the risk of peripheral arterial disease (PAD). We hypothesised that a higher intake of fish and a concomitant lower intake of poultry or red meat were associated with a lower risk of incident PAD. METHODS: We used data from a Danish cohort where middle-aged participants filled in food frequency and lifestyle questionnaires at baseline. During follow-up, we identified participants with valid diagnoses of PAD and analysed data by multivariable Cox regression analyses. Substitutions of 150 g/week of either poultry, red meat (processed or unprocessed) with 150 g/week of fish (total, lean or fatty) were explored. RESULTS: We followed the cohort (n = 54,597) for a median of 13.6 years and identified 897 cases with PAD. We found modest lower rates of PAD when intake of fish replaced a concomitant lower intake of unprocessed (HR 0.94, 95% CI 0.88-1.01) and processed red meat (HR 0.94, 95% CI 0.87-1.02). Replacing unprocessed (HR 0.89, 95% CI 0.79-1.00) or processed red meat (HR 0.88, 95% CI 0.78-1.01) with fatty fish was associated with lower rates of PAD. No associations were observed when fish intake replaced poultry or when lean fish replaced red meat. CONCLUSIONS: This study suggests that substituting red meat with fish and especially fatty fish may be associated with a lower risk of PAD, although not statistically significant. Replacing poultry with fish was not associated with the risk of PAD.

Trans-fatty Acids and Survival in Renal Transplantation.

OBJECTIVE: High consumption of trans-fatty acids (TFAs) is associated with increased mortality. DESIGN AND METHODS: Observational cohort study of 1.988 Norwegian renal transplant recipients with a median follow-up time of 9.6 years. We assessed multivariable adjusted associations between plasma levels of industrial and ruminant TFAs with patient and graft survival. Plasma phospholipid fatty acid levels were determined by gas chromatography at 10 weeks after transplantation. RESULTS: During follow-up, there were 595 deaths, and 805 grafts were lost. Plasma industrial TFA levels dropped from 0.3 wt% in years 1999-2004 to reach a plateau of 0.2 wt% from year 2005 and beyond, whereas plasma levels of ruminant TFAs remained stable throughout the study period. In the former era (years 1999 to 2004, n = 902), we found multivariable adjusted associations between plasma industrial TFA levels and mortality (hazard ratio 4.44, P = .02) and graft loss (hazard ratio 4.22, P = .01). In the latter era (years 2005 to 2011, n = 1,086), there were no associations between plasma industrial TFA levels and patient or graft survival. Plasma ruminant TFAs were not associated with mortality or graft loss in either eras. CONCLUSION: In this Norwegian transplant cohort, plasma industrial TFA levels dropped from around 0.3 wt% in the former era to 0.2 wt% in the latter era. While plasma industrial TFA was significantly associated with survival in the former era, no associations were found with survival in the latter era. This finding suggests that lowering industrial TFA consumption from modest to low levels could possibly influence health beneficially after renal transplantation.

Plasma n-6 Polyunsaturated Fatty Acid Levels and Survival in Renal Transplantation.

OBJECTIVE: The major n-6 polyunsaturated fatty acids linoleic acid (LA) and arachidonic acid (AA) play a role in inflammation and glucose metabolism, which could affect patient and renal transplant survival. DESIGN AND METHODS: In this single center cohort study of 1988 Norwegian renal transplant recipients, we assessed associations between plasma levels of LA and AA at baseline, measured by gas chromatography, and patient and graft survival, as well as inflammation and cardiovascular risk markers. RESULTS: During follow-up (median of 9.6 years), 595 patients died and 805 renal transplants were lost, either due to recipient death or graft failure. In multivariable survival analysis, we found no associations with mortality for plasma levels of LA (hazard ratios: 0.99, 95% confidence intervals: 0.96-1.01) or AA (hazard ratios: 1.01, 95% confidence intervals: 0.96-1.06). No associations were found for cardiovascular mortality, overall graft loss, or death-censored graft loss. Plasma glucose, proglycemic marker chemerin, and proinflammatory marker growth differentiation factor 15 were inversely associated with plasma LA and positively associated with plasma AA levels in multivariable analysis. CONCLUSIONS: We found no associations between plasma levels of LA or AA and patient or graft survival. Plasma levels of LA and proglycemic indices were inversely associated, signaling a possible beneficial effect of LA consumption for prevention of posttransplantation diabetes mellitus.

The effect of marine n-3 polyunsaturated fatty acids on cardiac autonomic and hemodynamic function in patients with psoriatic arthritis: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: The aim of this study was to investigate the effect of marine n-3 polyunsaturated fatty acids (PUFA) on cardiac autonomic function and vascular function in patients with psoriatic arthritis. METHODS: The study was conducted as a randomized, double-blind, placebo-controlled trial, where 145 patients with psoriatic arthritis were supplemented with 3 g of n-3 PUFA or olive oil (control) daily for 24 weeks. Blood pressure, heart rate, heart rate variability (HRV), central blood pressure, pulse wave velocity (PWV) and fatty acid composition of granulocytes, were determined at baseline and after supplementation. RESULTS: At baseline we found a significant difference in the mean of all normal RR intervals (inverse of heart rate, vary from beat to beat) when comparing subjects with the highest vs the lowest fish intake (p = 0.03). After supplementation for 24 weeks there was a trend towards an increase in RR (p = 0.13) and decrease in heart rate (p = 0.12) comparing the n-3 PUFA group with the control group. However, per-protocol analysis showed significantly increased RR (p = 0.01) and lowered heart rate (p = 0.01) in the n-3 PUFA supplemented patients compared with controls. Blood pressure, PWV and Central blood pressure did not change after supplementation with n-3 PUFA. Adjustment for disease activity and conventional cardiovascular risk factors did not change the results. CONCLUSIONS: Marine n-3 PUFA increased RR intervals in patients with psoriatic arthritis which may suggest a protective effect of n-3 PUFA against cardiovascular disease in this population. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01818804.

Plasma n-3 Polyunsaturated Fatty Acids and Bone Mineral Density in Renal Transplant Recipients.

OBJECTIVE: Renal transplant recipients (RTR) suffer high rates of bone loss and increased risk of fracture. Marine n-3 polyunsaturated fatty acids (n-3 PUFA), found mainly in fish and seafood, may have beneficial effects on bone and are positively associated with bone mineral density (BMD) in healthy elderly. The aim of this study was to investigate if this association prevails despite the more complex causes of bone loss in RTR. DESIGN, SUBJECTS, AND METHODS: A total of 701 RTR were included in a cross-sectional analysis. BMD of lumbar spine, proximal femur, and distal forearm were measured by dual energy x-ray absorptiometry scan, and blood samples were drawn in the fasting state for measurement of plasma fatty acid composition 10 weeks posttransplant. Multiple linear regression analysis was used to assess the association between plasma marine n-3 PUFA levels and BMD. RESULTS: Mean age was 52.2 years, and two-thirds were men. Based on femoral neck T-scores, 26% of patients were osteoporotic and 52% osteopenic. Z-scores increased significantly across quartiles of marine n-3 PUFA levels, and marine n-3 PUFA was a positive predictor of BMD at total hip and lumbar spine after multivariate adjustment. No association was found between n-6 PUFA content and BMD. CONCLUSIONS: Plasma marine n-3 PUFA levels were positively associated with BMD at the hip and lumbar spine 10 weeks posttransplant.

High Lipoprotein(a) May Explain One-Quarter of Clinical Familial Hypercholesterolemia Diagnoses in Danish Lipid Clinics.

CONTEXT: Cholesterol carried in lipoprotein(a) adds to measured low-density lipoprotein cholesterol (LDL-C) and may therefore drive some diagnoses of clinical familial hypercholesterolemia (FH). OBJECTIVE: We investigated plasma lipoprotein(a) in individuals referred to Danish lipid clinics and evaluated the effect of plasma lipoprotein(a) on a diagnosis of FH. METHODS: Individuals referred to 15 Danish lipid clinics who were suspected of having FH according to nationwide referral criteria were recruited between September 1, 2020 and November 30, 2021. All individuals were classified according to the Dutch Lipid Clinical Network criteria for FH before and after LDL-C was adjusted for 30% cholesterol content in lipoprotein(a). We calculated the fraction of individuals fulfilling a clinical diagnosis of FH partly due to elevated lipoprotein(a). RESULTS: We included a total of 1166 individuals for analysis, of whom 206 fulfilled a clinical diagnosis of FH. Median lipoprotein(a) was 15 mg/dL (29 nmol/L) in those referred and 28% had lipoprotein(a) greater than or equal to 50 mg/dL (105 nmol/L), while 2% had levels greater than or equal to 180 mg/dL (389 nmol/L). We found that in 27% (55/206) of those fulfilling a clinical diagnosis of FH, this was partly due to high lipoprotein(a). CONCLUSION: Elevated lipoprotein(a) was common in individuals referred to Danish lipid clinics and in one-quarter of individuals who fulfilled a clinical diagnosis of FH, this was partly due to elevated lipoprotein(a). These findings support the notion that the LPA gene should be considered an important causative gene in patients with clinical FH and further support the importance of measuring lipoprotein(a) when diagnosing FH as well as for stratification of cardiovascular risk.

Osteoprotegerin and mortality in hemodialysis patients with cardiovascular disease.

BACKGROUND: Patients treated with hemodialysis (HD) have an increased mortality, mainly caused by cardiovascular disease (CVD). Osteoprotegerin (OPG) is a glycoprotein involved in the regulation of the vascular calcification process. Previous studies have demonstrated that OPG is a prognostic marker of mortality. The aim of this study was to investigate if OPG was a prognostic marker of all-cause mortality in high-risk patients with end-stage renal disease and CVD. METHODS: We prospectively followed 206 HD patients with CVD. OPG was measured at baseline and the patients were followed for 2 years or until reaching the primary endpoint, i.e., all-cause mortality. RESULTS: All-cause mortality during follow-up was 44% (90/206). High OPG was associated with increased mortality, using the first tertile as reference, with an unadjusted HR of 1.70 (CI 1.00 - 2.88) for the second tertile and HR of 1.63 (CI 0.96 - 2.78) for the third tertile. In a multivariate Cox-regression analysis age, CRP and OPG in both the second and third tertile were significantly associated with increased mortality In the unadjusted survival analysis, a test for trend of OPG yielded a p-value of 0.08; in the adjusted analyses, the p-value for trend was 0.03. CONCLUSIONS: In a high-risk population of hemodialysis patients with previously documented cardiovascular disease, a high level of OPG was an independent risk marker of all-cause mortality.

The effect of low-dose marine n-3 fatty acids on plasma levels of sCD36 in overweight subjects: a randomized, double-blind, placebo-controlled trial.

CD36 is a scavenger receptor involved in lipid uptake and inflammation. Recently, non-cell-bound CD36 (sCD36) was identified in plasma and suggested to be a marker of lipid accumulation in the vessel wall. Marine n-3 polyunsaturated fatty acids (PUFA) may have cardioprotective effects. This study evaluated the effect of marine n-3 PUFA on sCD36 levels in overweight subjects. Fifty overweight subjects were randomized to 1.1 g of n-3 PUFA or 2 g of olive oil daily for six weeks. Neutrophils were isolated at baseline and after six weeks of treatment while an adipose tissue biopsy was obtained at baseline. The content of n-3 PUFA in adipose tissue and neutrophils was analyzed by gas chromatography, while plasma levels of sCD36 were determined using an enzyme-linked immunosorbent assay (ELISA). After six weeks of supplement plasma sCD36 did not differ between supplements (P = 0.18). There was no significant correlation between plasma sCD36 levels and n-3 PUFA in neutrophils at baseline (r = -0.02, P = 0.88), after six weeks supplement (r = -0.03, P = 0.85) or in adipose tissue (r = 0.14, P = 0.34). This study therefore does not provide evidence for a cardioprotective effect of n-3 PUFA acting through a CD36-dependent mechanism.