Hemodialysis and biomarkers of myocardial infarction - a cohort study.

OBJECTIVES: End-stage renal disease is associated with a high risk of cardiovascular disease. We compared the concentration and prognostic ability of high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) and cardiac myosin-binding protein C (cMyC) among stable hemodialysis patients. METHODS: Patients were sampled before and after hemodialysis. We measured hs-cTnI, hs-cTnT and cMyC and used Cox regressions to assess the association between quartiles of concentrations and all-cause mortality and a combination of cardiovascular events and all-cause mortality during follow-up. RESULTS: A total of 307 patients were included, 204 males, mean age 66 years (SD 14). Before dialysis, 299 (99 %) had a hs-cTnT concentration above the 99th percentile, compared to 188 (66 %) for cMyC and 35 (11 %) for hs-cTnI. Hs-cTnT (23 %, p<0.001) and hs-cTnI (15 %, p=0.049) but not cMyC (4 %, p=0.256) decreased during dialysis. Follow-up was a median of 924 days (492-957 days); patients in the 3rd and 4th quartiles of hs-cTnT (3rd:HR 3.0, 95 % CI 1.5-5.8, 4th:5.2, 2.7-9.8) and the 4th quartile of hs-cTnI (HR 3.8, 2.2-6.8) had an increased risk of mortality. Both were associated with an increased risk of the combined endpoint for patients in the 3rd and 4th quartiles. cMyC concentrations were not associated with risk of mortality or cardiovascular event. CONCLUSIONS: Hs-cTnT was above the 99th percentile in almost all patients. This was less frequent for hs-cTnI and cMyC. High cTn levels were associated with a 3-5-fold higher mortality. This association was not present for cMyC. These findings are important for management of hemodialysis patients.

Hemodialysis leads to plasma depletion of lectin complement pathway initiator molecule ficolin-2.

INTRODUCTION: This study aimed to investigate changes in complement system-related molecules in patients undergoing hemodialysis. METHODS: Patients >18 years of age on maintenance hemodialysis were included. Using enzyme-linked immunosorbent assays (ELISA) methods complement related molecules ficolin-1, ficolin-2, ficolin-3 mannose-binding lectin, long pentraxin 3, complement activation products C3c, and complement activation potentials were measured before and after a single hemodialysis treatment. All patients were dialyzed with synthetic high flux filters >1.6 m2 , respectively, Polyamix and Polysulfone, and the Kt/V was maintained >1.3. FINDINGS: Three hundred and four patients were included. There was a modest decrease in plasma level of ficolin-1 (p < 0.001). Ficolin-2 was virtually depleted with median 3.9 (interquartile range [IQR]: 2.6-6.1, range 0.3-13.5) µg/ml before dialysis to median 0.0 (IQR: 0.0-0.5, range 0.0-5.5) µg/ml after dialysis (p < 0.001). No significant difference before and after hemodialysis was seen for mannose-binding lectin and long pentraxin 3 (p > 0.05). In a random subgroup of 160 patients ficolin-2-binding, ficolin-3-mediated lectin pathway capacity and classical pathway capacity were significantly decreased due to hemodialysis. The complement capacity of the alternative pathway was increased after hemodialysis (p = 0.0101), while mannose-binding lectin-mediated lectin pathway capacity was unaltered (p = 0.79). There was an increase in the complement activation product C3c (p < 0.0001), while the concentration of total C4 and C3 did not change (p > 0.158). Multivariate Cox proportional hazard analyses showed an increased risk for all-cause mortality with increasing ficolin-2 (p = 0.002) after hemodialysis. DISCUSSION: Plasma ficolin-2 was virtually depleted from the circulation after hemodialysis. However, elevated plasma ficolin-2 levels after hemodialysis was independently associated with increased mortality.

Mid-regional pro-atrial natriuretic peptide levels before and after hemodialysis predict long-term prognosis.

BACKGROUND: Mid-regional pro-atrial natriuretic peptide (MR-proANP) is a strong prognostic biomarker in cardiovascular disease but there is limited data for its use among patients undergoing dialysis. METHODS: This was a cohort study of patients receiving maintenance hemodialysis from two Danish centers. Blood sampling and echocardiography were performed before and after a dialysis session. We calculated the area under the curve (AUC) for the receiver operating characteristics for diagnosing heart failure and Cox regressions for cardiovascular events and all-cause mortality. RESULTS: Of the 306 patients, 284 (93%) had MR-proANP measurements both before and after dialysis. Median concentration was 642 pmol/L (IQR 419-858) before and 351 pmol/L (IQR 197-537) after dialysis, a mean decrease of 330 pmol/L (43%, CI 296-364, P < 0.001). MR-proANP concentration both before and after dialysis was negatively correlated to left ventricular ejection fraction with no difference in predictive ability for heart failure, AUC before and after dialysis were 0.60 (CI 0.50-0.70) and 0.61 (CI 0.51-0.71) (P = 0.40). Median follow-up was 32 months (IQR 31-33), during which 99 patients (32%) had a cardiovascular event and 110 (36%) died. A doubling of MR-proANP concentration was associated with a hazard ratio (HR) of 1.6 (CI 1.3-1.9) before and 1.7 (CI 1.4-2.0) after dialysis for mortality and a HR of 1.5 (CI 1.2-1.9) before and 1.4 (CI 1.2-1.7) after dialysis for cardiovascular events (all P < 0.001). CONCLUSION: The MR-proANP concentration is elevated among patients undergoing hemodialysis and decreases during dialysis. MR-proANP concentration both before, after and intra-dialysis change strongly predicted cardiovascular events and all-cause mortality.

Changes in left ventricular filling parameters before and after dialysis in patients with end stage renal disease.

The aim of this study was to investigate the grading of diastolic dysfunction (DD) in relation to hemodialysis in patients with end stage renal disease (ESRD) on hemodialysis (HD) Cardiovascular disease is prevalent in patients with ESRD and accounts for significant morbidity and mortality. Left ventricular hypertrophy (LVH) is common in ESRD but little is known about the impact of HD on currently recommended grading schemes for DD. Comprehensive echocardiographic data was obtained in consecutive patients with ESRD before (n = 247) and immediately after (n = 239) standard HD regimen. Grading of DD was performed according to current recommendations both pre- and post HD. Prior to HD, DD was classified as present in 83 patients (34%), indeterminate in 51 patients (21%) and absent in 113 patients (45%). Patients with DD at baseline compared to those without were older [67.3 years (13.1) vs. 63.2 (14.3), p = 0.037], were more likely to have diabetic- or hypertensive ESRD (43.4% vs. 35.4%, p = ns) and LVMi was significantly higher [119 g/cm2 (27.5) vs. 103 g/cm2 (24.3), p < 0.001]. After HD [mean HD time = 221 min (27.6), mean ultrafiltration volume = 2 L (1.1)], 39 patients (16%) exhibited sustained DD. These patients were older [69.4 years (14.5) vs. 65.0 years (13.9), p = 0.071], were more likely to have diabetic- or hypertensive ESRD (59% vs. 36%, p = 0.010). Myocardial adverse remodeling was more advanced with higher LVMi [127.4 g/m2 (27.5) vs. 106.5 g/m2 (25.3), p < 0.001], lower LVEF [44.7% (11.0) vs. 54.5% (8.7), p < 0.001] and more impaired GLS [- 13.4% (4.3) vs. - 15.8% (4.0), p = 0.006]. Echocardiographic evaluation of diastolic function in patients with ESRD on HD is critically dependent on timing relative to dialysis. The presence of sustained DD after volume unloading by HD identifies a population of patients with an adverse phenotype of blunted vascular response and severe cardiac remodeling.

FGF23 in hemodialysis patients is associated with left ventricular hypertrophy and reduced ejection fraction.

BACKGROUND: Fibroblast growth factor 23 (FGF23) is known to cause left ventricular hypertrophy (LVH), but controversy exists concerning its effect in dialysis. This study evaluated associations between FGF23 levels, echocardiography and prognosis in patients on hemodialysis (HD). METHODS: Patients >18 years on chronic HD were included in this cross-sectional study. Plasma C-terminal FGF23 concentration was measured with ELISA and transthoracic echocardiography was performed, both before and after HD treatment. RESULTS: 239 haemodialysis (HD) patients were included in the study. The FGF23 was median 3560RU/ml (IQR 1447-9952). The mean left ventricular mass index (LVMI) was 110.2±26.7g/m2 and the left ventricular ejection fraction (LVEF) was 52.7±9.9%. Defined by LVMI, LVH was found in 110 patients (46%), of which 92 (84%) had hypertension (p<0.01). Patients with LVH had FGF23 levels of 5319 RU/ml (IQR 1858-12,859) and those without 2496 RU/ml (IQR 1141-7028) (p<0.01). FGF23 was significant positive correlated with LVMI (p<0.01), and negatively to LVEF (p<0.01). In a multivariate analysis, FGF23 was correlated with LVEF (p<0.01), but only marginally to LVMI (p<0.01). Cardiovascular events in the follow up period was not correlated with FGF23. Furthermore, FGF23 was independently correlated with overall mortality (p<0.001). CONCLUSION: FGF23 was positively correlated with LVH and negatively to LVEF. FGF23 was an independent predictor for overall mortality.

YKL-40 in patients with end-stage renal disease receiving haemodialysis.

PURPOSE: This study aimed to determine serum YKL-40 in patients with end-stage renal disease (ESRD) on haemodialysis (HD) and to evaluate the prognostic value of serum YKL-40. METHODS: Patients >18 years on maintenance HD were included. Serum YKL-40 was measured using ELISA before and after a single HD treatment. RESULTS: A total of 306 patients were included. Median serum YKL-40 concentration was 238 µgL-1 (IQR: 193-291 µgL-1) before HD treatment and 198 µgL-1 (IQR: 147-258 µgL-1) after HD treatment, which corresponded to age-corrected 93th percentile in healthy subjects. All-cause mortality after 2.8 years was 35.9%. Patients with serum YKL-40 in the highest quartile compared with the lowest quartile had a univariate HR of 4.0 (95% CI: 2.2-7.3, p < 0.001) for all-cause mortality which decreased to 2.4 (95% CI: 1.1-4.5, p = 0.01) in multivariate analysis. Time-dependent receiver operating characteristic curves showed that serum YKL-40 after HD treatment had significant higher area under the curves from 90 d (p = 0.004) and throughout the rest of the follow-up period when compared to serum YKL-40 before HD treatment. CONCLUSION: YKL-40 was highly elevated in patients with ESRD on HD, and dialysis reduced serum YKL-40 concentrations approximately one-sixth. YKL-40 measured after dialysis was independently associated with mortality in HD patients.

The formation and design of the TRIAGE study--baseline data on 6005 consecutive patients admitted to hospital from the emergency department.

BACKGROUND: Patient crowding in emergency departments (ED) is a common challenge and associated with worsened outcome for the patients. Previous studies on biomarkers in the ED setting has focused on identification of high risk patients, and and the ability to use biomarkers to identify low-risk patients has only been sparsely examined. The broader aims of the TRIAGE study are to develop methods to identify low-risk patients appropriate for early ED discharge by combining information from a wide range of new inflammatory biomarkers and vital signs, the present baseline article aims to describe the formation of the TRIAGE database and characteristize the included patients. METHODS: We included consecutive patients ≥ 17 years admitted to hospital after triage staging in the ED. Blood samples for a biobank were collected and plasma stored in a freezer (-80 °C). Triage was done by a trained nurse using the Danish Emergency Proces Triage (DEPT) which categorizes patients as green (not urgent), yellow (urgent), orange (emergent) or red (rescusitation). Presenting complaints, admission diagnoses, comorbidities, length of stay, and 'events' during admission (any of 20 predefined definitive treatments that necessitates in-hospital care), vital signs and routine laboratory tests taken in the ED were aslo included in the database. RESULTS: Between September 5(th) 2013 and December 6(th) 2013, 6005 patients were included in the database and the biobank (94.1 % of all admissions). Of these, 1978 (32.9 %) were categorized as green, 2386 (39.7 %) yellow, 1616 (26.9 %) orange and 25 (0.4 %) red. Median age was 62 years (IQR 46-76), 49.8 % were male and median length of stay was 1 day (IQR 0-4). No events were found in 2658 (44.2 %) and 158 (2.6 %) were admitted to intensive or intermediate-intensive care unit and 219 (3.6 %) died within 30 days. A higher triage acuity level was associated with numerous events, including acute surgery, endovascular intervention, i.v. treatment, cardiac arrest, stroke, admission to intensive care, hospital transfer, and mortality within 30 days (p < 0.001). CONCLUSION: The TRIAGE database has been completed and includes data and blood samples from 6005 unselected consecutive hospitalized patients. More than 40 % experienced no events and were therefore potentially unnecessary hospital admissions.