Plasma Copeptin Concentrations Research Articles

Plasma copeptin concentration is a predictor of tolvaptan efficacy in patients with hepatic ascites

AbstractAimsNo solid evidence‐based opinion was raised regarding predictors of the degree of ascites reduction with tolvaptan. This retrospective cohort study aimed to examine whether serum copeptin concentration is a useful predictor of this.MethodsThe study population consisted of 80 patients with liver cirrhosis treated with tolvaptan for hepatic ascites effusions at Nara Medical University Hospital from May 2014 to December 2018. Forty‐three patients who lost >1.5 kg of body weight in the first week after starting tolvaptan were classified as good responders and the remaining 37 as poor responders. Various laboratory parameters were measured immediately before the start of tolvaptan therapy to examine factors associated with predicting its efficacy.ResultsIn the univariate analysis, no significant differences with respect to age (67.6 vs. 69.8 years, p > 0.05), sex, body mass index (24.8 vs. 23.7 kg/m2, p > 0.05), Child–Pugh score (9.4 vs. 9.7, p > 0.05), and Model for End‐stage Liver Disease score (11 vs. 12, p > 0.05) were found between the two groups. Conversely, aspartate transferase and alanine transaminase (ALT) levels were significantly lower in the good response group (52.9 ± 56.3 vs. 68.8 ± 50.7 U/L, p < 0.05; 26.2 ± 30.6 vs. 40.5 ± 33.5 U/L, p < 0.01), whereas serum copeptin and serum sodium concentrations were significantly higher (57.1 ± 15.0 vs. 45.8 ± 16.0 pg/mL, p < 0.01; 136.3 ± 3.4 vs. 133.8 ± 5.8 mEq/L, p < 0.05). In the multivariate analysis, serum copeptin concentration and ALT were statistically significant factors (p < 0.01, p < 0.05). Regression analysis of the association between the tolvaptan efficacy for refractory ascites and pretreatment serum copeptin concentration showed that a copeptin concentration cutoff of 45.9 pg/mL could predict treatment efficacy with a sensitivity, specificity, and area under the curve of 76.7%, 59.5%, and 0.71%, respectively.ConclusionSerum copeptin concentration may be a predictor of tolvaptan efficacy for refractory ascites effusion in Japanese patients with liver cirrhosis.

Cross-sectional analysis of racial differences in hydration and neighborhood deprivation in young adults

BackgroundInadequate hydration is associated with cardiovascular and kidney disease morbidity and all-cause mortality. Compared with White individuals, Black individuals exhibit a higher prevalence of inadequate hydration, which may contribute to racial health disparities. However, the underlying reasons for these differences in hydration remain unclear. ObjectiveThis cross-sectional study aimed to investigate whether neighborhood deprivation contributes to racial differences in hydration status. MethodsWe assessed 24 Black and 30 White college students, measuring 24-hour urine osmolality, urine flow rate, urine specific gravity, and plasma copeptin concentration. Participants recorded their food and fluid intake for 3 d to assess total water intake from food and beverages. Neighborhood socioeconomic deprivation was measured using a tract-level Area Deprivation Index. ResultsBlack participants exhibited higher urine osmolality (640 [314] compared with 440 [283] mOsm/kg H2O, respectively, P = 0.006) and lower urine flow rate (1.06 [0.65] compared with 1.71 [0.89] ml/min, respectively, P = 0.009) compared with White participants, indicating greater hypohydration among Black participants. Black participants reported lower total water intake from food and beverages than White participants (2.3 ± 0.7 compared with 3.5 ± 1.1 L/day, respectively, P < 0.01). Black participants exhibited higher copeptin than White participants (6.3 [3.1] compared with 4.5 [2.3] pmol/L, P = 0.046), and urine osmolality mediated 67% of the difference (P = 0.027). Black participants reported greater cumulative exposure to neighborhood deprivation during childhood (ages 0–18 y). Furthermore, neighborhood deprivation during childhood was associated with urine specific gravity (P = 0.031) and total water intake from food and beverages (P = 0.042) but did not mediate the racial differences in these measures. ConclusionOur data suggest that compared with White young adults, Black young adults are hypohydrated and exhibit higher plasma copeptin concentration, and that greater neighborhood deprivation is associated with chronic underhydration irrespective of race.This trial was registered at clinicaltrials.gov as NCT04576338.

Fibroblast growth factor 23 but not copeptin is independently associated with kidney failure and mortality in patients with chronic kidney disease.

Copeptin and intact fibroblast growth factor 23 (iFGF23) increase early during chronic kidney disease (CKD) and may be predictive of unfavourable outcomes. The aim of this study was to evaluate their respective associations with renal and vital outcomes in CKD patients. We included CKD patients from the NephroTest cohort with concomitant measurements of plasma copeptin and iFGF23 concentrations and isotopic glomerular filtration rate measurement (mGFR). The primary endpoint was a composite outcome including kidney failure (KF) (dialysis initiation, pre-emptive transplantation or a 57% decrease of mGFR, corresponding to doubling of serum creatinine) or death before KF. Hazard ratios (HRs) of the primary endpoint associated with log-transformed copeptin and iFGF23 concentrations were estimated by Cox models. The slope of mGFR over time was analysed using a linear mixed model. A total of 329 CKD patients (243 men, mean age 60.3±14.6years) were included. Among them, 301 with an mGFR >15ml/min/1.73m2 were included in survival and mGFR slope analyses. During a median follow-up of 4.61years (quartile 1-quartile 3: 3.72-6.07), 61 KFs and 32 deaths occurred. Baseline iFGF23 concentrations were associated with the composite outcome after multiple adjustments {HR 2.72 [95% confidence interval (CI) 1.85-3.99]}, whereas copeptin concentrations were not [HR 1.01 (95% CI 0.74-1.39)]. Neither copeptin nor iFGF23 were associated with mGFR slope over time. Our study shows for the first time in population of CKD patients an independent association between iFGF23 and unfavourable renal and vital outcomes and shows no such association regarding copeptin, encouraging the integration of iFGF23 measurement into the follow-up of CKD.

The relationship between arginine vasopressin gene polymorphisms and plasma copeptin and hypertensive disorders of pregnancy: a nested case-control study.

This study aims to explore the relationship between polymorphism of the arginine vasopressin (AVP) gene and plasma copeptin concentration with the occurrence of hypertension in pregnancy. We conducted a matched nested case-control study in Chinese women. The genotypes of rs3729965, rs3761249, rs1410713, rs2740204, and rs2282018 loci of AVP gene and plasma copeptin at 16-20 gestational weeks were detected in 288 patients with gestational hypertension (GH), 82 with preeclampsia (PE), and 14 with chronic hypertension with superimposed preeclampsia (CH-PE) and their healthy matched controls. For every natural logarithm unit increment in copeptin, the risks of GH and PE/CH-PE increased by 5.556 (adjusted odds ratio [aOR]: 6.556, 95% confidence interval [CI]: 2.734-15.717) and 3.312 times (aOR: 4.312, 95% CI: 1.168-15.914). Under the dominant model, the genotype CC + CT of rs2282018 and GG + GT of rs3761249 had higher risks of GH than genotype TT, with aORs of 1.757 (95% CI: 1.077-2.867) and 1.814 (95% CI: 1.111-2.963). Allele A of rs3729965 loci had a lower risk of PE/CH-PE than allele G (aOR: 0.441, 95% CI: 0.199-0.978). However, the frequencies of rs1410713 and rs2740204 genotypes were not significantly different between cases and controls. The model of copeptin combined with the AVP gene and traditional factors (TFs) had a higher ability than the TFs model in predicting GH and PE/CH-PE. Our study confirms that higher plasma copeptin and AVP gene variants are associated with the occurrence of GH and PE/CH-PE. The detection of copeptin and AVP gene in the early second trimester improves the predictive ability of TFs for GH and PE/CH-PE.

A step-by-step guide for the diagnosis and management of hyponatraemia in patients with stroke.

Hyponatraemia is common in patients with stroke and associated with adverse outcomes and increased mortality risk. The present review presents the underlying causes and provides a thorough algorithm for the diagnosis and management of hyponatraemia in stroke patients. Concomitant diseases and therapies, such as diabetes, chronic kidney disease and heart failure, along with diuretics, antidepressants and proton pump inhibitors are the most common causes of hyponatraemia in community. In the setting of acute stroke, the emergence of hyponatraemia might be attributed to the administration of hypotonic solutions and drugs (ie. mannitol and antiepileptics), poor solute intake, infections, as well as stroke-related conditions or complications, such as the syndrome of inappropriate secretion of antidiuretic hormone, cerebral salt wasting syndrome and secondary adrenal insufficiency. Diagnostically, the initial step is to differentiate hypotonic from non-hypotonic hyponatraemia, usually caused by hyperglycaemia or recent mannitol administration in patients with stroke. Determining urine osmolality, urine sodium level and volume status are the following steps in the differentiation of hypotonic hyponatraemia. Of note, specific parameters, such as fractional uric acid and urea excretion, along with plasma copeptin concentration, may further improve the diagnostic yield. Therapeutic options are based on the duration and symptoms of hyponatremia. In the case of acute or symptomatic hyponatraemia, hypertonic saline administration is recommended. Hypovolaemic chronic hyponatremia is treated with isotonic solution administration. Although fluid restriction remains the first-line treatment for the rest forms of chronic hyponatraemia, therapies increasing renal free water excretion may be necessary. Loop diuretics and urea serve this purpose in patients with stroke, whereas sodium-glucose transport protein-2 inhibitors appear to be a promising therapy. Nevertheless, it is yet unclear whether the appropriate restoration of sodium level improves outcomes in such patients. Randomized trials designed to compare therapeutic strategies in managing hyponatraemia in patients with stroke are required.

Role of copeptin in diagnosis and outcome prediction in patients with heart failure: a systematic review and meta-analysis

ABSTRACT Background/Context Heart failure (HF) is a heterogeneous condition characterized by increased morbidity and mortality. Objective This systematic review and meta-analysis of 19 studies was conducted to evaluate the role of copeptin in diagnosis and outcome prediction in HF patients. Materials and methods A systematic literature search for clinical trials reporting copeptin levels in HF patients was performed using EMBASE, PubMed, Cochrane Register of Controlled Trials, and Google Scholar. Articles from databases published by 2 January 2022, that met the selection criteria were retrieved and reviewed. The random effects model was used for analyses. Results Pooled analysis found higher mean copeptin levels in HF vs. non-HF populations (43.6 ± 46.4 vs. 21.4 ± 21.4; MD= 20.48; 95% CI: 9.22 to 31.74; p < 0.001). Pooled analysis of copeptin concentrations stratified by ejection fraction showed higher concentrations in HFrEF vs. HFpEF (17.4 ± 7.1 vs. 10.1 ± 5.5; MD= −4.69; 95% CI: −7.58 to −1.81; p = 0.001). Copeptin level was higher in patients with mortality/acute HF-related hospitalization vs. stable patients (31.3 ± 23.7 vs. 20.4 ± 12.8; MD= −13.06; 95% CI: −25.28 to −0.84; p = 0.04). Higher copeptin concentrations were associated with mortality and observed in all follow-up periods (p < 0.05). Conclusions The present meta-analysis showed that elevated copeptin plasma concentrations observed in HF patients are associated with an increased risk of all-cause mortality, thus copeptin may serve as predictor of outcome in HF.

The kinetic profiles of copeptin and mid regional proadrenomedullin (MR-proADM) in pediatric lower respiratory tract infections.

Kinetics of copeptin and mid regional proadrenomedullin (MR-proADM) during febrile pediatric lower respiratory tract infections (LRTI) are unknown. We aimed to analyze kinetic profiles of copeptin and MR-proADM and the impact of clinical and laboratory factors on those biomarkers. This is a retrospective post-hoc analysis of a randomized controlled trial, evaluating procalcitonin guidance for antibiotic treatment of LRTI (ProPAED-study). In 175 pediatric patients presenting to the emergency department plasma copeptin and MR-proADM concentrations were determined on day 1, 3, and 5. Their association with clinical characteristics and other inflammatory biomarkers were tested by non-linear mixed effect modelling. Median copeptin and MR-proADM values were elevated on day 1 and decreased during on day 3 and 5 (-26%; -34%, respectively). The initial concentrations of MR-proADM at inclusion were higher in patients receiving antibiotics intravenously compared to oral administration (difference 0.62 pmol/L, 95%CI 0.44;1.42, p<0.001). Intensive care unit (ICU) admission was associated with a daily increase of MR-proADM (increase/day 1.03 pmol/L, 95%CI 0.43;1.50, p<0.001). Positive blood culture in patients with antibiotic treatment and negative results on nasopharyngeal aspirates, or negative blood culture were associated with a decreasing MR-proADM (decrease/day -0.85 pmol/L, 95%CI -0.45;-1.44), p<0.001). Elevated MR-proADM and increases thereof were associated with ICU admission suggesting the potential as a prognostic factor for severe pediatric LRTI. MR-proADM might only bear limited value for decision making on stopping antibiotics due to its slow decrease. Copeptin had no added value in our setting.

Copeptin and insulin-like growth factor-1 predict long-term outcomes after aneurysmal subarachnoid hemorrhage: A large prospective cohort study

ObjectiveThe predictive roles of copeptin and insulin-like growth factor-1 (IGF-1) in aneurysmal subarachnoid hemorrhage (aSAH) remain controversial. We aimed to define the relationship between copeptin and IGF-1 levels and functional outcome as well as quality of life (QoL) after aSAH. MethodsPatients with aSAH were prospectively enrolled in a tertiary university hospital. Controls were sex- and age-matched healthy subjects. Plasma concentrations of copeptin and IGF-1 were measured on admission. Demographics and clinical, radiological and laboratory characteristics of the patients were collected. Favorable functional outcome was defined as modified Rankins≤2, and QoL was evaluated by the 36-Item Short Form Health Survey (SF-36) 1 year after aSAH. Uni- and multivariable analyses were performed. ResultsOne hundred eighteen patients were eligible, with 122 healthy controls were included in this study. Plasma copeptin levels were significantly higher and plasma IGF-1 was lower in patients than in controls. Both copeptin (adjusted HR 4.143 [1.120–15.328], p = 0.033) and IGF-1 levels (adjusted HR 0.089 [0.013–0.602], p = 0.013) were positively associated with 1-year mortality, while only single copeptin and IGF-1 concentrations were independent predictors of poor functional outcome and QoL, respectively. ConclusionsPlasma copeptin and IGF-1 levels are abnormal in patients with acute aSAH, and this may reliably predict long-term mortality, functional outcome and QoL.

Role of A1/A2 Neurons in the Dysregulation of Vasopressin Release and Dilutional Hyponatremia in Liver Disease

Purpose Inappropriate release of arginine vasopressin (AVP) has been linked to dilutional hyponatremia in patients with liver disease. Plasma AVP remains elevated leading to water retention, hypoosmolality, ascites formation, and a perceived decrease in plasma volume. The perceived decrease in plasma volume is sensed by the A1/A2 norepinephrine neurons in the caudal ventrolateral medulla (CVLM) and the nucleus tractus solitarius (NTS) respectively. We propose that these neurons provide the initial stimuli that activates AVP-secreting neurons in the supraoptic nucleus (SON) leading to increased plasma AVP and dilutional hyponatremia. Method We used the Bile duct ligation (BDL) rat model of liver failure for our experiments. Selective lesioning of the SON-projecting A1/A2 norepinephrine neurons was achieved using anti-DβH-Saporin [IT-03] (Advanced Targeting Systems). Plasma copeptin concentration was measured as a surrogate marker for plasma AVP using ELISA. Plasma osmolality and hematocrit measurements were also taken. Immunohistochemistry for delta fosB and dopamine beta-hydroxylase (DβH) was performed on brain tissue slices. The slices were viewed using an Olympus microscope (BX41) equipped for epifluorescence and images were taken using Olympus DP70 digital camera with DP manager software (version 2.2.1). The number of immunoreactive cells to ΔFosB and DβH were counted using Image J. Results We found that lesioning of the A1/A2 neurons in the Saporin/BDL group (n=9) caused a decrease in the plasma AVP concentration versus the Vehicle/BDL control group (n=6), p<0.05. However, the number of delta fosB immunoreactive A1/A2 cells was not significantly different. Lesioning of the A1/A2 neurons seemed to normalize osmolality and hematocrit in the BDL group. Although the difference was not statistically significant. Conclusion Our experiments suggests that A1/A2 neurons could be involved in the increased plasma AVP seen in male BDL rats as well as the decreased plasma osmolality.

Delta-Opioid Receptors Play a Role in the Control of Selected Parameters Related to Stress and Brain Plasticity Under Non-stress and/or Stress Conditions.

There is some evidence that delta-opioid receptors may be involved in the brain processes related to neuroprotection. The aim of the present studies was to test the hypothesis that endogenous opioid peptides acting via delta-opioid receptors can protect against stress-induced changes in factors related to brain plasticity and stress hormone release. Forty male adult Wistar rats were used. Half of the animals were exposed to sustained partial restraint stress (hypokinesis) lasting48h. Rats were treated with vehicle (isotonic saline) or the delta-opioid receptor antagonist naltrindole (3mg/kg/ml, s.c.) six times a day. The stressfulness of the model was confirmed by increased plasma concentrations of corticosterone and prolactin, the increase in anxiety behavior in the open field test, as well as the reduction of BrdU incorporation into newly formed DNA in the hippocampus. Treatment with naltrindole potentiated the stress-induced rise in aldosterone concentrations. The blockade of delta-opioid receptors resulted in a decrease in hippocampal BDNF gene expression independently of control or stress conditions. Treatment with naltrindole enhanced plasma concentrations of copeptin, a stable precursor of vasopressin. In conclusion, these results suggest that endogenous opioid peptides might play an inhibitory role in aldosterone release under stress conditions and in the control of vasopressin release independently of stress exposure. Endogenous opioids might stimulate hippocampal gene expression of the important neurotrophic factor BDNF via delta-opioid receptors.

Improving Neonatal and Maternal Outcome by Inducing Mild Labor before Elective Cesarean Section: The Lacarus Randomized Controlled Trial

Background: Newborns delivered by elective cesarean section (CS) are at higher respiratory risk than those delivered vaginally or by CS proceeded by labor (secondary CS). The oxytocin challenge test (OCT) induces uterine contractions that trigger the release of fetal hormones regulating lung fluid clearance during transition from the uterine to an air-breathing environment. Objectives: The aim is to summarize current evidence and outline the Lacarus trial protocol. Methods: Literature review informed the design of a randomized placebo-controlled multicenter trial of OCT preceding elective CS in 1,450 women with a singleton pregnancy due for CS at >35 weeks gestation, without preceding contractions, rupture of the membranes, or antenatal steroids. OCT comprises the infusion of oxytocin 5 IU/500 mL Ringer lactate at a rate of 12 mL/h, doubling every 10 min until inducing 5 uterine contractions per 15-min interval. The primary endpoint is the occurrence of neonatal respiratory morbidity within 24 h after birth. Secondary endpoints include biochemical and physiological parameters of fetal and maternal well-being, such as breastfeeding rate and fetal plasma copeptin concentrations. Conclusion: This is the first trial to test the hypothesis that oxytocin-induced contractions before elective CS is a promising application of physiologic principles gleaned from natural birth to improve neonatal and maternal outcomes.

The Emerging Role of Copeptin.

Direct measurement of the nonapeptide vasopressin has been limited by analyte instability ex vivo and in vivo rapid degradation, low serum concentrations requiring a sensitive assay and inherent secretory pulsatility. Copeptin is a 39 amino acid glycopeptide cleavage product of vasopressin synthesis with high stability, providing a marker of vasopressin secretion. Copeptin measurement has applications in diagnosis of diabetes insipidus and other diseases with altered vasopressin secretion. This review summarises our current understanding of serum copeptin measurement in diabetes insipidus and possible future applications of copeptin assays. As vasopressin is a stress hormone, there is emerging evidence on the use of copeptin for diagnosis and prognostication of disorders such as syndrome of inappropriate anti-diuretic hormone secretion, diabetes mellitus, critical illness, stroke, cardiovascular disease, respiratory disease, renal disease and thermal stress. Copeptin concentration measurement is likely to improve the diagnostic reliability of diabetes insipidus and, as a marker of stress, may have diagnostic or prognostic utility in specific clinical circumstances. Further studies are needed to determine if goal-directed therapy using plasma copeptin concentrations may improve patient outcomes.

Copeptin and renal function decline, cardiovascular events and mortality in type 1 diabetes.

Plasma copeptin is a surrogate of arginine vasopressin (AVP) secretion and is associated with a risk of renal and cardiovascular disease. We investigated associations between copeptin and renal events, cardiovascular events and mortality in type 1 diabetes (T1D). We conducted a prospective cohort study on 658 individuals with T1D from Steno Diabetes Center Copenhagen. Plasma copeptin concentrations and conventional risk factors were assessed at baseline. The five endpoints were traced through national registries and electronic laboratory records. Baseline mean age was 55 ± 13 years and estimated glomerular filtration rate (eGFR) was 81 ± 26 mL/min/1.73 m2. The median follow-up was 6.2 years (interquartile range 5.8-6.7); 123 participants reached a combined renal endpoint [decline in eGFR ≥30%, end-stage kidney disease (ESKD) or all-cause mortality], 93 had a decrease in eGFR ≥30%, 21 developed ESKD, 94 experienced a combined cardiovascular endpoint and 58 died from all causes. Higher copeptin was associated with all endpoints in unadjusted Cox regression analyses. Upon adjustment for baseline eGFR, the associations were attenuated and remained significant only for the combined renal endpoint and decrease in eGFR ≥30%. Results were similar upon further adjustment for other risk factors, after which hazard ratios for the two renal endpoints were 2.27 (95% confidence interval 1.08-4.74) and 4.49 (1.77-11.4), respectively, for the highest versus the lowest quartile of copeptin. Higher copeptin was an independent risk marker for a combined renal endpoint and decline in renal function. AVP may be a marker of renal damage or a factor whose contribution to renal and cardiovascular risk is partially mediated by renal damage.

Blood-based biomarkers for the long-term prognosis after acute ischemic stroke – results of the Linz Stroke Unit (LISU) study

Abstract Background The aim of our study was to evaluate the long-term prognostic value of blood-based biomarkers in comparison to the established National Institute of Health stroke scale (NIHSS) score in patients with acute ischemic stroke. Methods We measured plasma concentrations of IL-6, NT-proBNP, D-dimer, hs-cTnT, sST2, MR-proADM, MR-proANP, CT-proET-1, Copeptin, and Procalcitonin in 721 consecutive acute ischemic stroke patients within 24 h after admission to our stroke unit. Endpoint was all-cause mortality at 3 years. Results During follow-up, 199 patients died (28%). In univariate Cox proportional hazards regression analyses using a dichotomized approach according to median values, all blood-based biomarkers were associated with prognosis. However, in the multivariate analysis after adjustment for several clinical variables, only IL-6 &amp;gt;7 pg/mL (risk ratio, 3.00; 95% CI, 2.03–4.44; P&amp;lt;0.001), NT-proBNP &amp;gt;447 ng/L (risk ratio, 2.67; 95% CI, 1.81–3.92; P&amp;lt;0.001), NIHSS score &amp;gt;3 (risk ratio, 2.24; 95% CI, 1.63–3.07; P&amp;lt;0.001), Copeptin &amp;gt;13 pmol/L (risk ratio, 1.87; 95% CI, 1.34–2.61; P&amp;lt;0.001), and hs-cTnT &amp;gt;14 ng/L (risk ratio, 1.74; 95% CI, 1.21–2.49; P=0.001) remained independent predictors. ROC curve analysis for mortality prediction demonstrated a higher area under the curve (AUC) for IL-6 and NT-proBNP, respectively, when compared to the NIHSS score (IL-6 AUC 0.81 vs. NIHSS AUC 0.75; P=0.016 and NT-proBNP AUC 0.80 vs. NIHSS AUC 0.75; P=0.039) and similar AUCs when comparing the NIHSS with hs-TnT (hs-TnT AUC 0.77) and Copeptin (Copeptin AUC 0.72). Conclusions In this large cohort of patients with acute ischemic stroke the blood-based biomarkers IL-6, NT-proBNP, hs-cTnT, and Copeptin were strong and independent prognostic markers for 3-year all-cause mortality. IL-6 and NT-proBNP even outperformed the NIHSS score for long-term mortality prediction. ROC plots for 3-year all-cause mortality Funding Acknowledgement Type of funding source: None

Arginine-stimulated copeptin measurements in the differential diagnosis of diabetes insipidus: A prospective diagnostic study

Summary Background Differential diagnosis of diabetes insipidus is challenging. The most reliable approach is hypertonic saline-stimulated copeptin measurements. However, this test is based on the induction of hypernatraemia and requires close monitoring of plasma sodium concentrations. Arginine-stimulated copeptin measurements might provide an alternative, simple, and safe test. Methods In this prospective diagnostic study, we recruited a development cohort from University Hospital Basel, Basel, Switzerland, and a validation cohort from five centres in Basel, Aarau, Luzern, Bern, and St Gallen, Switzerland, and the University Hospital Wurzburg, Wurzburg, Germany. For both cohorts, patients were eligible for inclusion if they were aged 18 years or older, were newly referred with polyuria (>50 mL/kg bodyweight per day) or had a known diagnosis of central diabetes insipidus or primary polydipsia. We also recruited a comparator cohort of healthy controls in parallel to each cohort, comprising adults (aged 18 years and older, with normal drinking habits, and no history of polyuria) and children who underwent arginine stimulation to diagnose growth hormone deficiency (children were only included in the comparator cohort to the development cohort as proof of concept). Patients and healthy controls underwent arginine stimulation with measurement of plasma copeptin at baseline and 30, 45, 60, 90, and 120 min. The primary objective in the development cohort was to determine the diagnostic accuracy of plasma copeptin concentrations to discriminate between diabetes insipidus and primary polydipsia, and in the validation cohort was to confirm those results. Adverse effects of the test were monitored in all participants, with tolerability of the test rated using a visual analogue scale (VAS) that ranged from no (0) to maximum (10) discomfort. This trial is registered with ClinicalTrials.gov, number NCT00757276. Findings Between May 24, 2013, and Jan 11, 2017, 52 patients were enrolled in the development cohort (12 [23%] with complete diabetes insipidus, nine [17%] with partial diabetes insipidus, and 31 [60%] with primary polydipsia) alongside 20 healthy adults and 42 child controls. Between Oct 24, 2017, and June 27, 2018, 46 patients were enrolled in the validation cohort (12 [26%] with complete diabetes insipidus, seven [15%] with partial diabetes insipidus, and 27 [59%] with primary polydipsia) alongside 30 healthy adult controls (two patients in this cohort were excluded from the main analysis because of early vomiting during the test). In the pooled patient and control datasets, median arginine-stimulated copeptin concentrations increased in healthy adult controls (from 5·2 pM [IQR 3·3–10·9] to a maximum of 9·8 pM [6·4–19·6]) and in participants with primary polydipsia (from 3·6 pM [IQR 2·4–5·7] to a maximum of 7·9 pM [5·1–11·8]), but only minimally in those with diabetes insipidus (2·1 pM [IQR 1·9–2·7] to a maximum of 2·5 pM [1·9–3·1]). In the development cohort, a cutoff of 3·5 pM at 60 min provided the highest diagnostic accuracy of 94% (95% CI 84–98). The accuracy of this cutoff in the validation cohort was 86% (95% CI 73–94). By pooling the data from both cohorts, an optimal accuracy of 93% (95% CI 86–97) was reached at a cutoff of 3·8 pM copeptin at 60 min (sensitivity 93%, 95% CI 86–98; specificity 92%, 95% CI 84–100). The test was safe and well tolerated, with median VAS scores of 3·5 (IQR 2–4) in patients with diabetes insipidus, 3 (2–4) in those with primary polydipsia, 1 (1–3) in healthy adults, and 1 (0–5) in healthy children in the pooled participant dataset. Interpretation Arginine-stimulated copeptin measurements are an innovative test for diabetes insipidus with high diagnostic accuracy, and could be a simplified, novel, and safe diagnostic approach to diabetes insipidus in clinical practice. Funding Swiss National Science Foundation and University Hospital Basel.

The potential value of Copeptin and Pentraxin3 for evaluating the severity of coronary stenosis in patients with coronary artery disease

IntroductionCoronary artery disease (CAD) is an ischemic heart disease due to the narrowing of the coronary arteries resulting from atherosclerosis. Blood biomarkers have been well utilized for the diagnosis and prognosis of CAD. However, the value of biomarkers for evaluating coronary atherosclerosis remains to be clarified. This clinical investigation aimed to explore the potential value of biomarkers for evaluating the severity of coronary stenosis in CAD patients. MethodsThe extent of coronary atherosclerosis was accessed by the angiography-based quantitative measurement Gensini score (GS). Blood levels of Brain natriuretic peptide, Copeptin (CPP), Phosphodiesterase 9A, and Pentraxin3 (PTX3) were measured in 56 patients divided into three levels as low GS (n = 17), intermediate GS (n = 19) and high GS (n = 20) based on GS tertiles. ResultsWe found that plasma concentrations of CPP and PTX3 were significantly elevated in patients with high GS compared with the low GS group. In addition, Pearson correlation analysis showed that CPP and PTX3 were positively correlated with the GS. Furthermore, Receiver operating characteristics analysis demonstrated that both CPP and PTX3 exhibited discriminative capacities for evaluating the extent of coronary stenosis. ConclusionsLaboratory tests of CPP and PTX3 via non-invasive means may provide novel information for risk stratification and disease management in CAD patients before invasive angiographic approaches. This study opens the door for enormous opportunities to explore new biomarkers with better efficiency, sensitivity and specificity as alternative/additional methods for evaluating the severity of coronary atherosclerosis in CAD patients in future research.

Associations of cardiac stress biomarkers with incident type 2 diabetes and changes in glucose metabolism: KORA F4/FF4 study

BackgroundHigh N-terminal pro-brain-type natriuretic peptide levels have been associated with a lower risk of type 2 diabetes mellitus (T2D). However, less is known about other cardiac stress biomarkers in this context. Here we evaluated the association of mid-regional pro-atrial natriuretic peptide (MR-proANP), C-terminal pro-arginine vasopressin (copeptin), C-terminal pro-endothelin-1 (CT-proET-1) and mid-regional pro-adrenomedullin (MR-proADM) with incident T2D and changes in glucose metabolism.MethodsWe performed a prospective cohort study using data from the population-based KORA F4/FF4 study. 1773 participants (52.3% women) with MR-proANP measurements and 960 (52.7% women) with copeptin, CT-proET-1 and MR-proADM measurements were included. We examined associations of circulating plasma levels of MR-proANP, copeptin, CT-proET-1 and MR-proADM with incident T2D, the combined endpoint of incident prediabetes/T2D and with fasting and 2 h-glucose, fasting insulin, HOMA-IR, HOMA-B and HbA1c at follow-up. Logistic and linear regression models adjusted for age, sex, waist circumference, height, hypertension, total/HDL cholesterol ratio, triglycerides, smoking, physical activity and parental history of diabetes were used to compute effect estimates.ResultsDuring a median follow-up time of 6.4 years (25th and 75th percentiles: 6.0 and 6.6, respectively), 119 out of the 1773 participants and 72 out of the 960 participants developed T2D. MR-proANP was inversely associated with incident T2D (odds ratio [95% confidence interval]: 0.75 [0.58; 0.96] per 1-SD increase of log MR-proANP). Copeptin was positively associated with incident prediabetes/T2D (1.29 [1.02; 1.63] per 1-SD increase of log copeptin). Elevated levels of CT-proET-1 were associated with increased HOMA-B at follow-up, while elevated MR-proADM levels were associated with increased fasting insulin, HOMA-IR and HOMA-B at follow-up. These associations were independent of previously described diabetes risk factors.ConclusionsHigh plasma concentrations of MR-proANP contributed to a lower risk of incident T2D, whereas high plasma concentrations of copeptin were associated with an increased risk of incident prediabetes/T2D. Furthermore, high plasma concentrations of CT-proET-1 and MR-proADM were associated with increased insulin resistance. Our study provides evidence that biomarkers implicated in cardiac stress are associated with incident T2D and changes in glucose metabolism.

Mortality in cardiogenic shock is stronger associated to clinical factors than contemporary biomarkers reflecting neurohormonal stress and inflammatory activation

Purpose To validate the IABP-SHOCK II risk score in a Danish cohort and assess the association between the IABP-SHOCK II risk score and admission concentration of biomarkers reflecting neurohormonal – (Copeptin, Pro-atrial natriuretic peptide (proANP), Mid-regional pro-adrenomedullin (MRproADM)) and inflammatory (ST2) activation in patients with CS complicating ST segment elevation myocardial infarction (STEMI). Methods A total of 137 consecutive patients admitted with STEMI and CS at two tertiary heart centres were stratified according to the IABP-SHOCK II risk score (0–2; 3/4; 5–9), and had blood sampled upon admission. Results Plasma concentrations of Copeptin (median (pmol/L) score 0–2: 313; score 3/4: 682; score 5–9: 632 p < 0.0001), proANP (pmol/L) (1459; 2225; 2876 p = 0.0009) and MRproADM (nmol/L) (0.86; 1.2; 1.4 p = 0.04) were significantly associated with the risk score, whereas ST2 (ng/mL) was not (44; 60; 45 p = 0.23). The IABP-SHOCK II risk score predicted 30-day mortality (score 0–2: 22%; score 4/3: 51%; score 5–9: 72%, area under the curve (AUC): 0.73, plogrank < 0.0001), while the tested biomarkers did not (AUC: 0.51<plogrank < 0.57). Conclusion Plasma concentrations of Copeptin, MRproADM and proANP were associated with the IABP-SHOCK II risk score in STEMI patients admitted with CS. The risk score predicted 30-day mortality, with no improvement in prediction when concentrations of the assessed biomarkers were added.

Salt, but not protein intake, is associated with accelerated disease progression in autosomal dominant polycystic kidney disease

In autosomal dominant polycystic kidney disease (ADPKD), there are only scarce data on the effect of salt and protein intake on disease progression. Here we studied association of these dietary factors with the rate of disease progression in ADPKD and what the mediating factors are by analyzing an observational cohort of 589 patients with ADPKD. Salt and protein intake were estimated from 24-hour urine samples and the plasma copeptin concentration measured as a surrogate for vasopressin. The association of dietary intake with annual change in the estimated glomerular filtration rate (eGFR) and height adjusted total kidney volume (htTKV) growth was analyzed with mixed models. In case of significant associations, mediation analyses were performed to elucidate potential mechanisms. These patients (59% female) had a mean baseline age of 47, eGFR 64 mL/min/1.73m2 and the median htTKV was 880 mL. The mean estimated salt intake was 9.1 g/day and protein intake 84 g/day. During a median follow-up of 4.0 years, eGFR was assessed a median of six times and 24-hour urine was collected a median of five times. Salt intake was significantly associated with annual change in eGFR of-0.11 (95% confidence interval 0.20 --0.02] mL/min/1.73m2) per gram of salt, whereas protein intake was not (-0.00001 [-0.01 - 0.01] mL/min/1.73m2) per gram of protein). The effect of salt intake on eGFR slope was significantly mediated by plasma copeptin (crude analysis: 77% mediation, and, adjusted analysis: 45% mediation), but not by systolic blood pressure. Thus, higher salt, but not higher protein intake may be detrimental in ADPKD. The substantial mediation by plasma copeptin suggests that this effect is primarily a consequence of a salt-induced rise in vasopressin.

Early Stages of Obesity-related Heart Failure Are Associated with Natriuretic Peptide Deficiency and an Overall Lack of Neurohormonal Activation: The Copenhagen Heart Failure Risk Study

Objective:This study evaluated the associations between the natriuretic peptide activity and the neurohormonal response in non-obese and obese outpatients with and without heart failure (HF).Background:Obesity-related HF may be a distinct subtype of HF. Obesity is associated with lower plasma concentrations of natriuretic peptides. The associations between obesity and neurohormonal activation estimated by mid-regional pro-adrenomedullin (MR-proADM) and copeptin in patients with HF is not elucidated.Methods:This prospective cohort-study included 392 outpatients ≥60years, plus ≥1 risk-factor(-s) for HF (hypertension, ischemic heart disease, atrial fibrillation, diabetes, chronic kidney disease), and without known HF. Patients were categorized ‘non-obese’ BMI = 18.5–29.9 kg/m2 (n = 273) and ‘obese’ BMI ≥ 30 kg/m2 (n = 119). The diagnosis of HF required signs, symptoms, and abnormal echocardiography. NT-proBNP, MR-proANP, MR-proADM, and copeptin were analyzed.Results:Obese patients were younger, had a higher prevalence of diabetes and chronic kidney disease, but a lower prevalence of atrial fibrillation. A total of 39 (14.3%) non-obese and 26 (21.8%) obese patients were diagnosed with HF. In obese patients, HF was not associated with higher plasma concentrations of NT-proBNP (Estimate: 0.063; 95%CI: –0.037–1.300; P = 0.064), MR-proANP (Estimate: 0.207; 95%CI: –0.101–0.515; P = 0.187), MR-proADM (Estimate: 0.112; 95%CI: –0.047–0.271; P = 0.168), or copeptin (Estimate: 0.093; 95%CI: –0.333–0.518; P = 0.669). Additionally, obese patients with HF had lower plasma concentrations of NT-proBNP (Estimate: –0.998; 95%CI: –1.778–0.218; P = 0.012), and MR-proANP (Estimate: –0.488; 95%CI: –0.845–0.132; P = 0.007) compared to non-obese patients with HF, whereas plasma concentrations of MR-proADM (Estimate: 0.066; 95%CI: –0.119–0.250; P = 0.484) and copeptin (Estimate: 0.140; 95%CI: –0.354–0.633; P = 0.578) were comparable.Conclusions:Patients with obesity-related HF have natriuretic peptide deficiency and lack of increased plasma concentrations of MR-proADM and copeptin suggesting that patients with obesity-related HF have a blunted overall neurohormonal activity.