Low Levels of Selenoprotein P Are Associated With Cognitive Impairment in Patients Hospitalized for Heart Failure.

BACKGROUND: Selenoprotein P (SELENOP) is a transporter for selenium and has been shown to protect selenium-status maintenance in the brain against deficiency and to support neuronal development, neurogenesis and neurocognitive function. Selenium deficiency has previously been associated with cognitive impairment in various populations, but no studies have been carried out in subjects with heart failure (HF). PURPOSE: To explore whether SELENOP deficiency in subjects with acute HF is associated with cognitive impairment. METHODS: Plasma SELENOP, as measured by an immunoassay analysis, is a well-validated marker of plasma selenium status and has the benefit of providing information on the bioavailable fraction of selenium to preferentially supplied cells equipped with receptors for SELENOP uptake. SELENOP was measured in 320 subjects hospitalized for HF. Of the subjects, 187 also underwent 4 cognitive tests assessing global cognitive function: Montreal Cognitive Assessment (MoCA); information processing (Symbol Digit Modalities Test [SDMT]); visual attention and task switching (Trailmaking Test A [TMT-A]); and executive speed (A Quick Test of Cognitive Speed [AQT] form and color). Appropriate cutoffs were used for each cognitive test to define cognitive impairment. Cross-sectional associations between SELENOP concentrations and cognitive impairment, as defined by each cognitive test, were explored using multivariable logistic models. Further, multivariable logistic models exploring associations between selenium deficiency, defined as the lowest quartile of SELENOP levels, and cognitive impairment, defined by each cognitive test, were carried out. RESULTS: The 187 participants had a mean age of 73 (± 11.9) years; 31% were female and had a mean body mass index of 28.1 (± 5.6) kg/m2. Each 1 standard deviation increment in SELENOP concentrations was associated with lower odds of cognitive impairment, defined as a MoCA cut-off score < 23 (odds ratio [OR] 0.60; 95% CI 0.40-0.91; P = 0.017). Further, SELENOP concentrations in the lowest quartile (≤ 2.3 mg/L) were associated with cognitive impairment as measured by MoCA (OR 3.10; 95% CI 1.38-6.97; P = 0.006), SDMT (OR 2.26; 95% CI 1.10-4.67; P = 0.027) and TMT-A (OR 3.40; 95% CI 1.47-7.88; P = 0.004) but not by AQT form and color. CONCLUSIONS: In subjects admitted for HF, higher SELENOP concentrations were associated with better performance on the MoCA test, reflecting global cognition, and SELENOP deficiency was associated with cognitive impairment as defined by 3 cognitive tests.

Galectin-4 levels in hospitalized versus non-hospitalized subjects with obesity: the Malmö Preventive Project.

BACKGROUND: Obesity is strongly associated with the development of cardiovascular disease (CVD). However, the heterogenous nature of obesity in CVD-risk is still poorly understood. We aimed to explore novel CVD biomarkers and their possible association with presumed unhealthy obesity, defined as hospitalized subjects with obesity (HO). METHODS: Ninety-two proteins associated with CVD were analyzed in 517 (mean age 67 ± 6 years; 33.7% women) individuals with obesity (BMI ≥30 kg/m2) from the Malmö Preventive Project cohort, using a proximity extension array technique from the Olink CVD III panel. Individuals with at least one recorded hospitalization for somatic disease prior to study baseline were defined as HO phenotypes. Associations between proteins and HO (n = 407) versus non-hospitalized subjects with obesity (NHO, n = 110), were analyzed using multivariable binary logistic regression, adjusted for traditional risk factors. RESULTS: Of 92 analyzed unadjusted associations between biomarkers and HO, increased levels of two proteins were significant at a false discovery rate < 0.05: Galectin-4 (Gal-4) and insulin-like growth factor-binding protein 1 (IGFBP-1). When these two proteins were included in logistic regression analyses adjusted for age and sex, Gal-4 remained significant. Gal-4 was independently associated with the HO phenotype in multivariable logistic regression analysis (OR 1.72; CI95% 1.16-2.54). Post-hoc analysis revealed that this association was only present in the subpopulation with diabetes (OR 2.26; CI95% 1.25-4.07). However, an interaction analysis was performed, showing no significant interaction between Gal-4 and prevalent diabetes (p = 0.16). CONCLUSIONS: In middle-aged and older individuals with obesity, increased Gal-4 levels were associated with a higher probability of HO. This association was only significant in subjects with diabetes only, further implying a role for Gal-4 in diabetes and its complications.

The shrunken pore syndrome is associated with declined right ventricular systolic function in a heart failure population - the HARVEST study.

The close relationship between heart and kidney diseases was studied with respect to the 'Shrunken pore syndrome' that is characterized by a difference in renal filtration between cystatin C and creatinine. Patients were retrieved from the HeARt and brain failure inVESTigation trail (HARVEST) which is an ongoing study undertaken in individuals hospitalized for the diagnosis of heart failure. Ninety-five of 116 patients who underwent transthoracic echocardiograms (TTE) were eligible for this study. We used four different formulas for estimated glomerular filtration rate (eGFR); CKD-EPIcreatinine, CKD-EPIcystatin C, LMrev and CAPA. Presence of the syndrome was defined as eGFR cystatin C ≤ 60% of eGFR creatinine and absence of the syndrome as eGFR cystatin C >90% and <110% of eGFR creatinine. In a linear regression model, adjusted for age and sex, and the 'Shrunken pore syndrome' defined by the equation pair CAPA and LMrev and the equation pair CKD-EPIcystatin C and CKD-EPIcreatinine, echocardiographic parameters were studied. The 'Shrunken pore syndrome' showed statistically significant associations with measurements of right ventricular (RV) systolic function; (TAPSE and RV S') (according to the equation pair CKD-EPIcystatin C and CKD-EPIcreatinine). In conclusion, heart failure patients with the 'Shrunken pore syndrome' are at increased risk of having RV systolic dysfunction whilst heart failure patients without 'Shrunken pore syndrome' seem protected. These findings may indicate common pathophysiological events in the kidneys and the heart explaining the observed increased risk of mortality in subjects with the 'Shrunken pore syndrome'.

Association between low selenoprotein P concentrations and anaemia in hospitalized heart failure patients.

AIMS: Heart failure (HF) patients with anaemia tend to have a worse outcome, with increased hospitalization rates, decreased exercise tolerance, and higher mortality compared to those without anaemia. Limited research exists on the association between selenium deficiency and anaemia specifically in HF patients, despite previous findings of a correlation in different populations. The BIOSTAT-CHF study demonstrated that higher selenium levels in HF patients were associated to a lower risk of anaemia and iron deficiency. This study investigates the relationship between selenoprotein P (SELENOP) concentrations, a major contributor and functional biomarker of selenium transport, and anaemia, Hb levels, and iron status in hospitalized HF patients. METHODS AND RESULTS: SELENOP was analysed in 320 hospitalized HF subjects, with complete data available for 310 subjects. The relationships between continuous SELENOP concentrations and 1) Hb concentrations, 2) anaemia (Hb < 115 g/L (women), <130 g/L (men)), and 3) iron status (as measured by transferrin receptor 1 (TfR1) which increases in iron deficiency) were evaluated using multivariable logistic and linear regression models. Additionally, SELENOP concentrations in the lowest quartile were related to anaemia, haemoglobin, and iron state in multivariable logistic and linear models. The mean age of the study population was 75.0 ± 11.6 years, and 30% were women. Anaemia was present in 133 subjects (42.9%). SELENOP concentrations were positively correlated with haemoglobin concentrations (0.238; P < 0.001) and negatively with TfR1 concentrations (-0.238, P < 0.001). In multivariable regression models, higher SELENOP concentrations were associated with higher Hb concentrations (B = 3.23; P = 0.002) and lower TfR1 concentrations (B = -0.20; P < 0.001). Furthermore, SELENOP deficiency was associated with lower Hb concentrations (B = -7.64: P = 0.001), higher TfR1 concentrations (B = 0.31; P = 0.003), and higher odds of anaemia in HF patients (odds ratio 2.17; 95% confidence interval 1.23-3.82; P = 0.008). CONCLUSIONS: In hospitalized heart failure patients, lower concentrations of SELENOP were associated with higher prevalence of anaemia.

Selenoprotein P deficiency is associated with higher risk of incident heart failure.

INTRODUCTION: Selenium deficiency has been associated with mortality, cardiovascular disease and worsened prognosis in heart failure (HF). In a recent population-based study, high selenium levels were shown to be associated with reduced mortality and reduced incidence of HF, but only in non-smokers. Here, we aimed to examine if selenoprotein P (SELENOP), a main selenium carrier protein, is associated with incident HF. MATERIALS AND METHODS: SELENOP concentrations were measured in plasma of 5060 randomly selected subjects from the population-based prospective cohort "Malmö Preventive Project" (n = 18240) using an ELISA approach. Exclusion of subjects with prevalent HF (n = 230) and subjects with missing data on co-variates included in the regression analysis (n = 27) resulted in complete data for 4803 subjects (29.1% women, mean age 69.6 ± 6.2 years, 19.7% smokers). Cox regression models adjusted for traditional risk factors were used to analyse SELENOP's association with incident HF. Further, subjects within the quintile with the lowest SELENOP concentrations were compared to subjects in the remaining quintiles. RESULTS: Each 1 standard deviation increment in SELENOP levels was associated with lower risk of incident HF (n = 436) during a median follow-up period of 14.7 years (hazard ratio (HR) 0.90; CI95% 0.82-0.99; p = 0.043). Further analyses showed that subjects in the lowest SELENOP quintile were at the highest risk of incident HF when compared to quintiles 2-5 (HR 1.52; CI95% 1.21-1.89; p = 2.5 × 10-4). CONCLUSION: Low selenoprotein P levels are associated with a higher risk of incident HF in a general population. Further studies are warranted.

Galectin-4 is associated with diabetes and obesity in a heart failure population.

An association between high Galectin-4 (Gal-4) and prevalence of diabetes in subjects with heart failure (HF) has previously been reported. The purpose of this study was to confirm these findings, as well as to further investigate this association, in a Swedish HF population. In addition, a second aim was to explore Gal-4's association with obesity and biomarkers of metabolism and heart failure. Gal-4 was measured using a proximity extension array technique in 324 hospitalized HF patients within the Swedish HeArt and bRain failure investigation trial cohort. Obesity was defined as BMI ≥ 30. Multivariable logistic regression models were used to explore associations between Gal-4 and diabetes/obesity, and linear regression models were used to explore the associations between Gal-4 and biomarkers. A total of 309 participants (29.1% female; mean age 74.8 years) provided complete data for the analysis of associations between Gal-4 and diabetes. Additionally, for the analysis of heart failure phenotype, complete data was available for 230 subjects. Gal-4 was positively associated with prevalent diabetes (OR 2.60; CI 95% 1.56-4.32). In multivariable models, Gal-4 levels were significantly associated with obesity, but only for subjects with diabetes (OR 2.48; 1.09-5.62). Additionally, Gal-4 demonstrated a significant association with the incretin Glucose-dependent insulinotropic polypeptide (GIP), as well as with biomarkers of HF. In the stratified analyses, the association between Gal-4 and diabetes was prominent in patients with reduced ejection fraction (n = 160, OR 3.26; 95%CI 1.88-5.66), while it was not observed in those without (n = 70, 1.96 (0.75-5.10)). In this cross-sectional, observational study, higher Gal-4 levels in HF patients were associated with higher GIP levels. Further, increased levels of Gal-4 were associated with increased likelihood of diabetes, and obesity. This association was particularly pronounced in individuals with HF characterized by reduced ejection fraction. Additionally, Gal-4 levels were significantly elevated in heart failure patients with diabetes and obesity.

Physical Inactivity Is Associated With Post-discharge Mortality and Re-hospitalization Risk Among Swedish Heart Failure Patients-The HARVEST-Malmö Study.

Background: Several studies have examined the role of physical activity as a predictor of heart failure (HF) mortality and morbidity. Here, we aimed to evaluate the role of self-reported physical activity as an independent risk factor of post-discharge mortality and re-hospitalization in patients hospitalized for HF, as well as study the association between physical activity and 92 plasma proteins associated with cardiovascular disease (CVD). Methods: Four-hundred-and-thirty-four patients hospitalized for HF (mean age 75 years; 32% women) were screened for physical activity derived from questionnaires in the Swedish national public health survey. The median follow-up time to death and re-hospitalization was 835 (interquartile range, 390-1,432) and 157 (43-583) days, respectively. Associations between baseline reported physical activity, mortality and re-hospitalization risk were analyzed using multivariable Cox regression analysis. Plasma samples from 295 study participants were analyzed with a proximity extension assay consisting of 92 proteins. Associations between proteins and physical activity were explored using a false discovery rate of <5%, and significant associations were taken forward to multivariate analyses. Results: In the multivariate Cox regression model, physical inactivity, defined as physical activity time <1 h throughout the week was associated with increased risk of all-cause mortality (HR 1.71; CI95% 1.26-2.31; p = 5.9 × 10-4) as well as all-cause re-hospitalization (HR 1.27; CI95% 1.01-1.60; p = 0.038). Further, physical inactivity was associated with elevated plasma levels of Metalloproteinase inhibitor 4, Soluble interleukin 1 receptor-like 1, Elafin and Transferrin receptor protein 1, which are implicated in myocardial fibrosis, migration and apoptosis. Conclusions: Self-reported low weekly physical activity is associated with increased risk of mortality and re-hospitalization in patients hospitalized for HF independent of traditional risk factors. Furthermore, physical inactivity was associated with elevated levels of 4 proteins linked to cardiovascular disease.

The impact of myocardial fibrosis biomarkers in a heart failure population with atrial fibrillation-The HARVEST-Malmö study.

Background: Several studies suggest that circulating biomarkers of myocardial fibrosis are associated with worse prognosis in subjects with atrial fibrillation (AF). Here, we aimed to explore associations between fibrosis biomarkers, prevalent AF, and left atrial volume (LAV) enlargement in subjects with heart failure (HF). Additionally, we evaluated the prognostic impact of fibrotic biomarkers in HF with co-existing AF. Materials and methods: Patients hospitalized for HF (n = 316, mean age 75 years; 30% women) were screened for AF. Seven proteins previously associated with myocardial fibrosis [metalloproteinase inhibitor 4 (TIMP-4), suppression of tumorigenicity 2 (ST-2), galectin-3 (GAL-3), growth/differentiation factor-15 (GDF-15), and matrix metalloproteinase 2, 3, and 9 (MMP-3, MMP-3, and MMP-9, respectively)] were analyzed using a proximity extension assay. Proteins with significant Bonferroni-corrected associations with mortality and re-hospitalization risk were taken forward to multivariable Cox regression analyses. Further, Bonferroni-corrected multivariable logistic regression models were used to study associations between protein plasma levels, prevalent AF, and severely enlarged left atrial volume index (LAVI ≥ 48 ml/m2). Results: Prevalent AF was observed in 194 patients at the hospitalization of whom 178 (92%) were re-hospitalized and 111 (57%) died during the follow-up period. In multivariable logistic regression models, increased plasma levels of TIMP-4, GDF-15, and ST-2 were associated with the prevalence of AF, whereas none of the seven proteins showed any significant association with severely enlarged LAVI. Increased plasma levels of five proteins yielded significant associations with all-cause mortality in patients with co-existing AF; TIMP-4 (HR 1.33; CI95% 1.07-1.66; p = 0.010), GDF-15 (HR 1.30; CI95% 1.05-1.62; p = 0.017), GAL-3 (HR 1.29; CI95% 1.03-1.61; p = 0.029), ST-2 (HR 1.48; CI95% 1.18-1.85; p < 0.001), and MMP-3 (HR 1.33; CI95% 1.09-1.63; p = 0.006). None of the proteins showed any significant association with re-hospitalization risk. Conclusion: In this study, we were able to demonstrate that elevated levels of three plasma proteins previously linked to myocardial fibrosis are associated with prevalent AF in a HF population. Additionally, higher levels of five plasma proteins yielded an increased risk of mortality in the HF population with or without co-existing AF.

Proteins linked to atherosclerosis and cell proliferation are associated with the shrunken pore syndrome in heart failure patients: Shrunken pore syndrome and proteomic associations.

PURPOSE: The "Shrunken pore syndrome" (SPS) is characterized by a difference in renal filtration between cystatin C and creatinine, resulting in a low eGFRcystatinC /eGFRcreatinine -ratio. Studies have demonstrated a high risk for cardiovascular morbidity and mortality for patients with SPS. In this discovery study, we explored associations between SPS and proteins implicated in cardiovascular disease and inflammation in patients with heart failure. EXPERIMENTAL DESIGN: Plasma samples from 300 individuals in HARVEST-Malmö trial hospitalized for the diagnosis of heart failure (mean age 74.9 ± 11.5 years; 30.0% female), were analyzed with a proximity extension assay consisting of 92 proteins. A Bonferroni-corrected p-value of 0.05/92 = 5.4 × 10-4 was considered significant in the initial age and sex-adjusted analyses. Presence of SPS was defined as eGFRcystatinC ≤ 60% of eGFRcreatinine . RESULTS: SPS presented with significant associations (p < 5.4 × 10-4 ) in age and sex-adjusted logistic regressions with elevated levels of six proteins; scavenger receptor cysteine rich type 1 protein M130, tumor necrosis factor receptor 1, tumor necrosis factor receptor 2, osteoprotegerin, interleukin-2 receptor subunit alpha, and tyrosine-protein kinase receptor UFO. All proteins remained associated (p < 0.05) with SPS after multivariate adjustments. CONCLUSIONS AND CLINICAL RELEVANCE: In heart failure patients, SPS was associated with proteins linked to atherosclerosis and cell proliferation.

Impaired cerebral oxygenation in heart failure patients at rest and during head-up tilt testing.

AIMS: Heart failure (HF) confers potentially negative effects on the brain and autonomic nervous system. The measurement cerebral tissue oxygen saturation (SctO2 ) may aid in understanding such effects. We aimed to investigate if compensated HF affects SctO2 at rest and during orthostatic challenge. METHODS AND RESULTS: Non-invasive haemodynamic monitoring and near-infrared spectroscopy were applied during head-up tilt (HUT) in 61 HF patients [mean (SD) 71 (11) years, 82% male, New York Heart Association (NYHA) class I-III] and 60 controls [60 (12) years, 42% male). Group differences in continuous variables were compared using Student's t-test. Associations between HF and SctO2 were studied using multivariable linear regression models adjusted for age, sex, diabetes, smoking, systolic blood pressure (SBP), and heart rate in supine position and after 10 min of HUT. Mean SctO2 was lower in HF patients compared with controls both in the supine position (67 vs. 71%; P < 0.001) and after 10 min of HUT (64 vs. 69%; P < 0.001). The HUT-induced SctO2 decrease was greater in HF patients compared with controls (P = 0.026). SBP did not change in neither HF patients nor controls during HUT, whereas diastolic blood pressure and heart rate increased in both groups. HF was associated with lower SctO2 in supine (B = -2.5%, P = 0.023) and after 10 min of HUT (B = -2.6%, P = 0.007) after multivariable adjustments. CONCLUSIONS: Cerebral tissue oxygenation is lower in HF patients both at rest and during orthostasis compared with subjects without HF. Future studies should test if the lower cerebral oxygenation associates with negative prognosis and with impaired cognitive function.

Cognitive test results are associated with mortality and rehospitalization in heart failure: Swedish prospective cohort study.

AIMS: We aimed to search for associations between cognitive test results with mortality and rehospitalization in a Swedish prospective heart failure (HF) patient cohort. METHODS AND RESULTS: Two hundred and eighty-one patients hospitalized for HF (mean age, 74 years; 32% women) were assessed using cognitive tests: Montreal Cognitive Assessment (MoCA), A Quick Test of Cognitive speed, Trail Making Test A, and Symbol Digit Modalities Test. The mean follow-up time censored at rehospitalization or death was 13 months (interquartile range, 14) and 28 months (interquartile range, 29), respectively. Relations between cognitive test results, mortality, and rehospitalization risk were analysed using multivariable Cox regression model adjusted for age, sex, body mass index, systolic blood pressure, atrial fibrillation, diabetes, smoking, educational level, New York Heart Association class, and prior cardiovascular disease. A total of 80 patients (29%) had signs of cognitive impairment (MoCA score < 23 points). In the fully adjusted Cox regression model using standardized values per 1 SD change of each cognitive test, lower score on MoCA [hazard ratio (HR), 0.75; confidence interval (CI), 0.60-0.95; P = 0.016] and Symbol Digit Modalities Test (HR, 0.66; CI, 0.48-0.90; P = 0.008) yielded significant associations with increased mortality. Rehospitalization risk (n = 173; 62%) was significantly associated with lower MoCA score (HR, 0.84; CI, 0.71-0.99; P = 0.033). CONCLUSIONS: Two included cognitive tests were associated with mortality in hospitalized HF patients, independently of traditional risk factors. In addition, worse cognitive test scores on MoCA heralded increased risk of rehospitalization.

A diabetes-associated genetic variant is associated with diastolic dysfunction and cardiovascular disease.

AIMS: Although the epidemiological association between Type 2 diabetes and congestive heart failure (CHF) as well as cardiovascular disease (CVD) is well established, associations between diabetes-related single-nucleotide polymorphisms (SNPs), CHF, and CVD have been surprisingly inconclusive. Our aim is to examine if 43 diabetes-related SNPs were associated with prevalent diastolic dysfunction assessed by echocardiography and incident CVD and/or CHF. METHODS AND RESULTS: We genotyped 43 SNPs that previously reported genome-wide significant associations with Type 2 diabetes, in 1444 subjects from the population-based Malmö Preventive Project-Re-examination Study (MPP-RES) (mean age 68 years; 29% women, 36% prevalent diabetes) (discovery cohort) and in 996 subjects from the VARA cohort (mean age 51 years, 52% women, 7% prevalent diabetes) (replication cohort). Multivariable logistic regression was assessed. Genetic variants that reached significant association with diastolic dysfunction in both cohorts were then analysed for association with incident CVD/CHF in a larger sample of the MPP-RES cohort (3,407 cases and 11,776 controls, median follow up >30 years) using Cox regression analysis. A common variant at the HNF1B [major allele (T) coded, also the risk allele for diabetes] was the only SNP associated with increased risk of prevalent diastolic dysfunction in both the discovery [MPP-RES; odds ratio (OR) 1.21, P = 0.024), and the replication cohort (VARA; OR 1.38, P = 0.042]. Cox regression analysis showed that carriers of the T-allele of rs757210 had an increased risk of future CVD (HR 1.05, P = 0.042). No significant association was seen for incident CHF. CONCLUSIONS: The diabetes susceptibility locus HNF1B is associated with prevalent diastolic dysfunction in two independent Swedish cohorts as well as incident cardiovascular disease.

Proteomic exploration of common pathophysiological pathways in diabetes and cardiovascular disease.

AIMS: The epidemiological association between diabetes and cardiovascular disease is well established, but the pathophysiological link is complex and multifactorial. We investigated seven proteins, previously linked to incident diabetes mellitus, and their association with cardiovascular disease and mortality. METHODS AND RESULTS: Plasma samples from 1713 individuals from the Swedish population-based Malmö Preventive Project (mean age 67.4 ± 6.0 years; 29.1% women) were analysed with a proximity extension assay panel. Seven proteins [scavenger receptor cysteine rich type 1 protein M130 (CD163), fatty acid-binding protein 4 (FABP4), plasminogen activator inhibitor 1 (PAI), insulin-like growth factor-binding protein 2 (IGFB2), cathepsin D (CTSD), galectin-4 (GAL4), and paraoxonase-3 (PON3)] previously shown to be associated with incident diabetes were analysed for associations with all-cause mortality (ACM), cardiovascular mortality (CVM), incident coronary events (CEs), and incident heart failure (HF). After exclusion of prevalent cases of respective outcome, proteins that met Bonferroni-corrected significance were analysed in multivariable Cox regression models. Significant associations were identified between five proteins [GAL4 (hazard ratio; 95% confidence interval: 1.17-1.41), CTSD (1.15-1.37), CD163 (1.09-1.30), IGFBP2 (1.05-1.30), and FABP4 (1.04-1.29)] and ACM and four proteins [GAL4 (1.38-1.56), CTSD (1.14-1.43), CD163 (1.09-1.36), and IGFBP2 (1.03-1.35)] with CVM. Three proteins [GAL4 (1.14-1.57), CTSD (1.12-1.50), and FABP4 (1.05-1.55)] were significantly associated with incident CE and two [GAL4 (1.03-1.54) and CTSD (1.01-1.46)] were associated with incident HF after adjusting for traditional risk factors including N-terminal pro-brain natriuretic peptide. CONCLUSIONS: In a general Swedish population, four proteins previously shown to be associated with diabetes were associated with ACM and CVM. Three proteins were associated with incident CE. Finally, GAL4 and CTSD displayed novel associations with incident HF and were the only proteins associated with all outcomes.

Exploration of pathophysiological pathways for incident atrial fibrillation using a multiplex proteomic chip.

Objective: Atrial fibrillation (AF) is the most common arrhythmia and associated with increased morbidity and mortality. Its increasing prevalence calls for novel biomarkers to identify underlying pathophysiological mechanisms as well as patients at risk. Methods: Plasma samples from 1694 individuals from the Swedish population-based Malmö Preventive Project (mean age 69.5 years; 29.3% female; mean follow-up time 9.7±3.1 years) were analysed with the Olink proximity extension assay CVD III panel consisting of 92 proteins to identify proteins associated with incident AF or atrial flutter, referred to as incident AF. Incident cases of AF (n=278) were retrieved by linkage to the registers. Participants were followed until the first episode of AF or until censoring by death or emigration. Bonferroni-corrected multivariable Cox regression models adjusted for known risk factors were used to explore possible associations of the 92 proteins and incidence of AF. Results: Multivariable Cox regression analyses of 11 proteins associated with incident AF (mean follow-up time 9.7±3.1 years) after Bonferroni correction confirmed N-terminal pro-B-type natriuretic peptide (HR per 1 SD increment (95% CI) 1.80 (1.58 to 2.04); p=1.2×10-19) as risk marker of incident AF. Further, matrix metalloproteinase-2 (1.22 (1.07 to 1.39); p=0.002) and osteopontin (1.27 (1.12 to 1.44); p=2.7×10-4) were associated with incident AF at follow-up independently of traditional risk markers and NT-proBNP. Conclusion: In a general Swedish population, we confirmed the well-known association of NT-proBNP with incident AF and also identified matrix metalloproteinase-2 and osteopontin as novel risk markers for incident AF, independently of traditional risk factors and NT-proBNP.

Cardiovascular biomarkers predict post-discharge re-hospitalization risk and mortality among Swedish heart failure patients.

AIM: The aim of this study was to assess the predictive role of biomarkers, associated with cardiovascular stress and its neuroendocrine response as well as renal function, in relation to mortality and risk of re-hospitalization among consecutive patients admitted because of heart failure (HF). METHODS AND RESULTS: A total of 286 patients (mean age, 75 years; 29% women) hospitalized for newly diagnosed or exacerbated HF were analysed. Associations between circulating levels of mid-regional pro-adrenomedullin (MR-proADM), copeptin, C-terminal pro-endothelin-1, N-terminal pro-brain natriuretic peptide (NT-proBNP), cystatin C, and all-cause mortality as well as risk of re-hospitalization due to cardiac causes were assessed using multivariable Cox regression models. A two-sided Bonferroni-corrected P-value of 0.05/5 = 0.010 was considered statistically significant. All biomarkers were related to echocardiographic measurements of cardiac dimensions and function. A total of 57 patients died (median follow-up time, 17 months). In the multivariable-adjusted Cox regression analyses, all biomarkers, except C-terminal pro-endothelin-1, were significantly associated with increased mortality: NT-proBNP [hazard ratio (HR) 1.85, 95% confidence interval (CI) 1.17-2.17; P = 4.0 × 10-4 ], MR-proADM (HR 1.94, 95% CI 1.36-2.75; P = 2.2 × 10-4 ), copeptin (HR 1.70, 95% CI 1.22-2.36; P = 0.002), and cystatin C (HR 2.11, 95% CI 1.56-2.86; P = 1.0 × 10-6 ). A total of 90 patients were re-hospitalized (median time to re-hospitalization, 5 months). In multivariable Cox regression analyses, NT-proBNP was the only biomarker that showed significant association with risk of re-hospitalization due to cardiac causes (HR 1.43, 95% CI 1.10-1.87; P = 0.009). CONCLUSIONS: Among patients hospitalized for HF, elevated plasma levels of NT-proBNP, MR-proADM, copeptin, and cystatin C are associated with higher mortality after discharge, whereas NT-proBNP is the only biomarker that predicts the risk of re-hospitalization due to cardiac causes.

Using a Targeted Proteomics Chip to Explore Pathophysiological Pathways for Incident Diabetes- The Malmö Preventive Project.

Multiplex proteomic platforms provide excellent tools for investigating associations between multiple proteins and disease (e.g., diabetes) with possible prognostic, diagnostic, and therapeutic implications. In this study our aim was to explore novel pathophysiological pathways by examining 92 proteins and their association with incident diabetes in a population-based cohort (146 cases of diabetes versus 880 controls) followed over 8 years. After adjusting for traditional risk factors, we identified seven proteins associated with incident diabetes. Four proteins (Scavenger receptor cysteine rich type 1 protein M130, Fatty acid binding protein 4, Plasminogen activator inhibitor 1 and Insulin-like growth factor-binding protein 2) with a previously established association with incident diabetes and 3 proteins (Cathepsin D, Galectin-4, Paraoxonase type 3) with a novel association with incident diabetes. Galectin-4, with an increased risk of diabetes, and Paraoxonase type 3, with a decreased risk of diabetes, remained significantly associated with incident diabetes after adjusting for plasma glucose, implying a glucose independent association with diabetes.

Bioactive adrenomedullin, proenkephalin A and clinical outcomes in an acute heart failure setting.

Objectives: In an acute heart failure (AHF) setting, proenkephalin A 119-159 (penKid) has emerged as a promising prognostic marker for predicting worsening renal function (WRF), while bioactive adrenomedullin (bio-ADM) has been proposed as a potential marker for congestion. We examined the diagnostic value of bio-ADM in congestion and penKid in WRF and investigated the prognostic value of bio-ADM and penKid regarding mortality, rehospitalisation and length of hospital stay in two separate European AHF cohorts. Methods: Bio-ADM and penKid were measured in 530 subjects hospitalised for AHF in two cohorts: Swedish HeArt and bRain failure inVESTigation trial (HARVEST-Malmö) (n=322, 30.1% female; mean age 75.1+11.1 years; 12 months follow-up) and Italian GREAT Network Rome study (n=208, 54.8% female; mean age 78.5+9.9 years; no follow-up available). Results: PenKid was associated with WRF (area under the curve (AUC) 0.65, p<0.001). In multivariable logistic regression analysis of the pooled cohort, penKid showed an independent association with WRF (adjusted OR (aOR) 1.74, p=0.004). Bio-ADM was associated with peripheral oedema (AUC 0.71, p<0.001), which proved to be independent after adjustment (aOR 2.30, p<0.001). PenKid was predictive of in-hospital mortality (OR 2.24, p<0.001). In HARVEST-Malmö, both penKid and bio-ADM were predictive of 1-year mortality (aOR 1.34, p=0.038 and aOR 1.39, p=0.030). Furthermore, bio-ADM was associated with rehospitalisation (aOR 1.25, p=0.007) and length of hospital stay (ß=0.702, p=0.005). Conclusion: In two different European AHF cohorts, bio-ADM and penKid perform as suitable biomarkers for early detection of congestion severity and WRF occurrence, respectively, and are associated with pertinent clinical outcomes.

Autonomic dysfunction is associated with cardiac remodelling in heart failure patients.

AIMS: Orthostatic hypotension (OH) is a cardinal sign of autonomic dysfunction and a common co-morbidity in heart failure (HF). The role of autonomic dysfunction in the development of structural cardiac anomalies in HF patients has not been sufficiently explored. We aimed to assess relations between orthostatic blood pressure (BP) responses during active standing and echocardiographic changes in a series of patients admitted for HF. METHODS AND RESULTS: One hundred and forty-nine patients hospitalized for HF [mean age: 74 years; 30% women; ejection fraction (LVEF) 40 ± 16%] were examined with conventional echocardiograms and active-standing test. Associations of cardiac remodelling parameters with the difference between supine and standing (after 3 min) systolic/diastolic BP were examined. Systolic BP decreased (-1.1 ± 15 mmHg), whereas diastolic BP increased (+1.0 ± 9.5 mmHg) after 3 min of active standing. A total of 34 patients (23%) met conventional OH criteria; i.e. systolic/diastolic BP decreases by ≥20/10 mmHg. In the multivariable linear regression analysis, adjusted for traditional cardiovascular risk factors and LVEF, a decrease in systolic BP upon standing was associated with greater left atrial volume [ß per -10 mmHg: 2.37, standard error (SE) = 1.16, P = 0.043], and greater left ventricular mass (ß per -10 mmHg: 5.67, SE = 2.24, P = 0.012), but not with other echocardiographic parameters. No significant associations were observed between signs of cardiac remodelling and decrease in diastolic BP. CONCLUSIONS: Orthostatic decrease in systolic BP among older HF patients is associated with structural cardiac changes such as increased left atrial volume and left ventricular mass, independently of traditional risk factors and left ventricular dysfunction.

Cystatin C and Risk of Diabetes and the Metabolic Syndrome - Biomarker and Genotype Association Analyses.

BACKGROUND: We recently reported a relationship between plasma levels of cystatin C and incidence of the metabolic syndrome (MetS) among the first 2,369 subjects who participated in the re-examination study of the population-based Malmö and Diet Cancer Cardiovascular cohort (MDC-CC-re-exam). In this study we aimed to replicate these results and also investigate if cystatin C was causally associated with MetS and diabetes. METHODS: We estimated the effect size of the strongest GWAS derived cystatin C SNP (major allele of rs13038305) on plasma cystatin C in the now completed MDC-CC-re-exam (n = 3,734) and thereafter examined the association between plasma cystatin C (403 cases of diabetes and 2665 controls) as well as rs13038305 (235 cases and 2425 controls) with incident diabetes. The association of rs13038305 and incident MetS (511 cases of MetS and 1980 controls) was similarly investigated in the whole MDC-CC-re-exam. We also attempted to replicate our previously shown association of cystatin C with incident MetS in subjects from the MDC-CC-re-exam (147 cases and 711 controls) that were not included in our previous report. RESULTS: In the entire MDC-CC-re-exam, each copy of the major allele of rs13038305 was associated with approximately 0.30 standard deviation (SD) higher plasma concentration of cystatin C (ß = 0.33, p = 4.2E-28) in age and sex adjusted analysis. Cystatin C in plasma was not associated with incident diabetes after adjustment for known diabetes risk factors (OR per 1 SD increment 0.99 (0.86-1.13), p = 0.842). In the replication cohort of MDC-CC-re-exam, the OR (95% CI) for incident MetS in subjects belonging to quartiles 1, 2, 3 and 4 of plasma cystatin C levels was 1.00 (reference), 1.21 (0.70-2.07), 1.62 (0.95-2.78) and 1.72 (1.01-2.93) (ptrend = 0.026) in age and sex adjusted analysis. In the entire MDC-CC-re-exam the odds ratio for incident MetS and diabetes per copy of the major rs13038305 allele was 1.13, (0.95-1.34), p = 0.160 and 1.07, 95% CI 0.89-1.30, p = 0.478, respectively. CONCLUSION: We were able to replicate our previously shown association between high levels of cystatin C and increased risk of future development of MetS. However, a causal involvement of cystatin C in the etiology of MetS or diabetes seems unlikely since genetic elevation of plasma cystatin C was not significantly related to incidence of these diseases.