Distribution of plasma copeptin levels and influence of obesity in children and adolescents

Copeptin Levels During Cardiac Surgery

OBJECTIVES

To investigate copeptin levels during the full perioperative course in open, adult cardiac surgery with cardiopulmonary bypass (CPB).

DESIGN

Prospective cohort study.

SETTING

A single-center study conducted in a tertiary care hospital.

PARTICIPANTS

We included 61 patients undergoing various cardiac surgical procedures. In the final analysis, 57 patients were evaluated. Patients were divided into 2 subgroups based on preoperative copeptin levels, either above or below the reference level of 10 pmol/L.

INTERVENTIONS

No intervention.

MEASUREMENTS AND MAIN RESULTS

Copeptin levels were measured at multiple time points preoperatively, perioperatively, and postoperatively. Copeptin levels significantly increased from a preoperative median of 6.6 pmol/L (interquartile range [IQR], 3.9-11.0) to 27 pmol/L (IQR, 15.0-66.0 pmol/L) after sternotomy (p ≤ 0.001). Peak levels occurred 60 minutes after CPB initiation, reaching 286 pmol/L (IQR, 163-446 pmol/L). After this, the copeptin levels did not drop significantly until CPB termination at 179.5 pmol/L (IQR, 136.0-346.0 pmol/L) (p ≤ 0.001). Subsequent decreases were observed upon arrival in the intensive care unit and throughout the postoperative period. However, at 4 days postoperatively, copeptin levels remained significantly higher (11.5 pmol/L; IQR,7.2-19.0 pmol/L; p ≤ 0.001), than preoperative levels.

CONCLUSIONS

This study describes copeptin levels during the perioperative course in adult cardiac surgery. The elevated levels during CPB suggest a strong activation of the arginine vasopressin system, with peak levels exceeding those seen in septic shock. This knowledge will enable further targeted clinical studies on copeptin as a prognostic marker in the field of cardiac surgery.

The effect of phlebotomy and placement of an intravenous catheter on plasma catecholamine and serum copeptin concentrations

OBJECTIVES

Limited data are available on the hormonal response of children to venepuncture or intravenous cannulation (IVC). Catecholamines (epinephrine (E) and norepinephrine (NE)) have been traditionally recognized as stress hormones. Copeptin, the carboxyl-terminus of the arginine vasopressin (AVP) precursor peptide, is also a known marker for stressful stimuli, including myocardial infarction, critical illness, and sepsis. We aimed to measure the above stress markers in response to IVC in the pediatric population.

METHODS

We measured plasma E, NE and serum copeptin concentrations in 100 children aged 5-17 years undergoing endocrine testing. Labs were drawn 1-3 min (min) after placement of IV cannula (baseline or 0 min) and then re-measured 20 min later (+20 min) while subjects rested in a quiet room.

RESULTS

Between 0 and 20 min, the median (IQR) NE (n=99) changed from 349 (244, 482) pg/mL to 253 (184, 348) pg/mL (p<0.001); E (n=54) changed from 57 (43, 116) pg/mL to 57 (38, 96) pg/mL (p=0.024); Copeptin changed from 9.4 (6.3, 15.2) pmol/L to 9 (5, 13) pmol/L (p<0.001). The mean decrease (delta) was 106 pg/mL for NE (28 %, p<0.001), 16 pg/mL for E (18 %, p=0.042) and 2.7 pmol/L for copeptin (17 %, p=0.012). There was no correlation between the decrease (expressed as a percentage) in NE vs. E, E vs. copeptin, and NE vs. copeptin.

CONCLUSIONS

Our data suggest that the stress of IVC induces a rapid increase in NE, E, as previously described, as well as copeptin levels. The copeptin decrement, concordant with the catecholamine trend in the minutes after IVC, supports this peptide (and AVP) as a rapid response marker of stress, and has unclear practical implications for copeptin measurements in evaluating fluid and sodium metabolism disorders in children.

Copeptin as a diagnostic and prognostic biomarker in pediatric diseases

Arginine vasopressin (AVP) plays a main role in maintaining the homeostasis of fluid balance and vascular tone and in regulating the endocrine stress response in response to osmotic, hemodynamic and stress stimuli. However, the difficulty in measuring AVP limits its clinical application. Copeptin, the C-terminal part of the AVP precursor, is released in an equimolar concentration mode with AVP from the pituitary but is more stable and simple to measure. Therefore, copeptin has emerged as a promising surrogate marker of AVP with excellent potential for the diagnosis, differentiation and prognosis of various diseases in recent decades. However, its application requires further validation, especially in the pediatric population. This review focuses on the clinical value of copeptin in different pediatric diseases and the prospects for its application as a potential biomarker.

Plasma Copeptin as a Prognostic Marker in Children with Heart Failure

OBJECTIVE

To investigate the role of plasma copeptin in predicting mortality in children with heart failure (HF) in addition to poor outcomes, including sepsis, multiorgan dysfunction syndrome, need for mechanical ventilation, and duration of stay in the pediatric intensive care unit.

METHODS

This diagnostic study included 76 children aged 1 month to 16 years who were hospitalized with congenital or acquired heart disease with HF, and an age- and gender-matched control group of 65 healthy children. Plasma copeptin level was evaluated within 24 hours of admission. Patient with HF were classified into quartiles according to copeptin levels.

RESULTS

The median plasma copeptin level (pmol/L) was significantly higher in children with HF compared to the healthy children (16.8 vs 8.0; P = 0.001). Patients were classified into quartiles according to their plasma copeptin level as follows; Q1, plasma copeptin level < 7.60 pmol/L; Q2, plasma copeptin level 7.60-10.75 pmol/L; Q3, plasma copeptin level 10.76-17.70 pmol/L; Q4, plasma copeptin level >17.70 pmol/L. The Pediatric Risk of Mortality III (PRISM III) score and inotropic scores were significantly different among the quartiles of copeptin levels in HF (P = 0.001 and 0.003, respectively). A higher proportion of patients who developed sepsis and MODS were in the fourth quartile (P = 0.001 and 0.022, respectively). All mechanically ventilated children were also in the fourth quartile. Plasma copeptin level of 35.5 pmol/L had a sensitivity of 72% and a specificity of 92.5% to predict mortality in children with HF (AUC = 0.72, P = 0.046).

CONCLUSION

Plasma copeptin is a novel biomarker for the early prediction of mortality and poor outcomes in children with HF.

Paediatric perspectives in the diagnosis of polyuria-polydipsia syndrome

The elucidation of the underlying cause of polyuria-polydipsia syndrome (PPS) is a challenging-especially in the differentiation of partial defects of arginine vasopressin (AVP) secretion or action from primary polydipsia. The water deprivation test has been utilized for many decades, and its application in the paediatric population has been applied using parameters predominantly established in adult cohorts. In more recent times, the development of automated commercial assays for copeptin, a surrogate marker for AVP, has represented a significant advancement in the diagnostic approach to PPS. Measurement of copeptin concentrations has major advantages and has essentially superseded measurement of AVP in diagnostic protocols for PPS. Additionally, stimulated-copeptin protocols utilizing hypertonic saline infusion, arginine, and glucagon have been investigated, and are promising. However, further studies are required in the population-incorporating the differences in physiological regulation of water homeostasis, and safety requirements-before there is widespread adoption into clinical practice.

The influence of insulin-induced hypoglycemia on copeptin concentrations

Plasma copeptin is a biomarker that reflects arginine vasopressin (AVP) secretion. In this study we measured copeptin during insulin tolerance test (ITT) in 65 patients referred to our department for evaluation of anterior pituitary function. Plasma for measurements of copeptin were collected at the start of the test and regurarly up to 120 minutes thereafter. Of 60 patients who developed significant hypoglycemia and were included in the analyses, 13 (22%) had corticotropic deficiency, 11 (18%) had thyreotropic deficiency, 33 (55%) had growth hormone deficiency and 4 (6%) had AVP deficieny (AVPD). Thirty-seven (62%) patients had at least one anterior pituitary deficiency. In patients without AVPD, median (range) copeptin increased from 4.5 pmol/L (1.3-33.0) to a maximum of 6.2 pmol/L (2.0-34.4; p<0.001). Baseline copeptin was similar in men and women, but maximal copeptin during ITT was higher in men. Copeptin concentrations were not affected by age, BMI, somatotropic, or corticotropic function. Copeptin concentrations were lower in patients with AVPD than patiets without AVPD, and in patients with thyrotropic deficiency, compared to patients with intact thyrotropic function, both at baseline and during ITT. In conclusion, copeptin increases significantly during insulin induced hypoglycemia but is of limited value in predicting anterior pituitary hormonal function.

Copeptin Stimulation by Combined Intravenous Arginine and Oral LevoDopa/Carbidopa in Healthy Short Children and Children with the Polyuria-Polydipsia Syndrome

INTRODUCTION

Stimulated copeptin may provide an alternative to water deprivation testing (WDT) in the evaluation of polyuria-polydipsia syndrome (PPS). Though best studied, arginine stimulation alone produces a modest copeptin response in children. We investigated the effectiveness of the arginine + LevoDopa/Carbidopa stimulation test (ALD-ST) for copeptin.

METHODS

47 healthy short children (controls), 10 children with primary polydipsia, and 10 children with AVP deficiency received arginine hydrochloride (500 mg/kg intravenously over 30 min) and Levodopa/carbidopa (10:1 ratio; 175 mg of l-Dopa/m2 BSA) orally. Serum copeptin was measured at 0, 60, 90, and 120 min.

RESULTS

In controls, ALD-ST increased copeptin from a median of 7.0 pmol/L (IQR 5.0-10.0) to a peak of 44.0 pmol/L (IQR 21.4-181.0) between 60 and 120 min (p < 0.001). Copeptin peak was higher in subjects who experienced nausea or vomiting (57%) than in those who did not (131.0 pmol/L [IQR 42.5-193.8] vs. 22.7 pmol/L [IQR 16.0-33.7], p < 0.001). While subjects with primary polydipsia had similar baseline (8.5 pmol/L [IQR 8.0-11.0]) and stimulated (125.2 pmol/L [IQR 87.6-174.0]) copeptin levels as controls, subjects with AVP deficiency had lower baseline (2.5 pmol/L [IQR 2.0-3.1]) and peak levels (4.6 pmol/L [IQR 2.4-6.0]). A peak copeptin of ≥9.3 pmol/L best predicted absence of complete or partial AVP deficiency with a sensitivity of 100% and specificity of 80%.

CONCLUSIONS

ALD-ST induced a robust peak copeptin in healthy short children and children with primary polydipsia. Nausea/vomiting, a side effect of ALD-ST, amplified the copeptin response. The ALD-ST may be a suitable initial screening test in children with PPS.

Zonulin and copeptin relation to some metabolic markers in school-aged obese children

BACKGROUND

Using Zonulin and Copeptin as potential obesity markers in children, hasn't yet been focused.

AIM

To evaluate the association between serum levels of both Zonulin and Copeptin with the obesity markers, and to assess their role as metabolic disturbance predictors in obese children.

METHODS

A case-control study comprised 111 Egyptian children (45 males and 66 females); aged 6-10 years to avoid the effect of puberty (prepubertal). They were classified according to their body mass index (BMI) percentiles into: 72 obese (BMI ≥ 95th ), and 39 control ones (BMI > 15th - <85th ), based on the Egyptian Growth Charts for children and adolescents. Anthropometric parameters and blood pressure were measured, and body composition analysis, lipid profile, Zonulin, and Copeptin levels were assessed.

RESULTS

The obese group showed a significantly higher value of Copeptin and a lower value of Zonulin than the control one Also, the obese group showed significant negative correlations between Zonulin and both anthropometric obesity markers and body composition, whereas Copeptin showed significant positive ones. Moreover, significant positive correlations were found between Copeptin and both body weight and fat distribution. Insignificant correlations were observed between both serum Zonulin and Copeptin levels and blood pressure and lipid profile.

CONCLUSION

Zonulin and Copeptin cannot be used as metabolic disturbance predictors, among Egyptian children, as they were insignificantly correlated with lipid profile or blood pressure.

Very elevated serum copeptin concentrations occur in a subset of healthy children in the minutes after phlebotomy

OBJECTIVES

Although AVP and its surrogate, copeptin, are mainly regulated by osmotic and volume stimuli, their secretion is also elicited by stress and growth hormone (GH) stimulating agents. The aim of this report is to describe unusual patterns of copeptin response in a subset of children undergoing GH stimulation tests (GH-ST).

METHODS

We conducted a secondary analysis of a cohort of 93 healthy short children with no polydipsia, polyuria or fluid/electrolyte abnormalities, undergoing GH-ST with intravenous arginine, insulin, oral clonidine, or L-Dopa/carbidopa in various combinations. Serum copeptin concentrations were measured 1-3 min after phlebotomy (0 min) and at 60, 90, 120 min during GH-ST.

RESULTS

In 85 subjects (normal response group, NRG) serum copeptin concentrations increased from a 0 min median of 9 pmol/L (IQR 6, 11.5) (all values ≤21) to a median peak between 60 and 120 min of 22 (IQR15, 38) pmol/L, which varied depending on the stimulating agent. Conversely, in the eight outliers, copeptin concentrations decreased gradually from a median of 154 (IQR 61, 439) pmol/L (all ≥40 pmol/L) to values as low as 14 % of the basal value, by 120 min. Test-associated anxiety was described in 17 subjects in the NRG (20 %) and five of the outliers (63 %).

CONCLUSIONS

A distinctive pattern of very elevated serum copeptin concentrations occurred in 9 % of children undergoing GH-ST, similar to reports in previous pediatric studies. Etiology may include pain or stress of phlebotomy. This phenomenon should be recognized for proper interpretation of copeptin values in children.

Fibroblast growth factor-21 and Visfatin as potential predictors for metabolic risk factors in obese children

Fibroblast growth factor-21 (FGF-21) and Visfatin are associated with obesity. However; reviewing the literature; no studies were found to assess their role as potential markers for the metabolic disorders related to obesity in children. Assess the relations between serum FGF-21 and Visfatin with obesity and its metabolic disorders, and their use as potential predictors for metabolic risk factors in a sample of Egyptian obese children. This cross-sectional study included 111 Egyptian children (45 males and 66 females); aged 6-10 years to avoid the effect of puberty (prepubertal). The exclusion criteria (by full History taking and clinical examination) were the presence of any sign of puberty according to Tanner stage, the presence of identified causes of obesity (genetic syndromes, chromosomal or endocrinal disorders), chronic diseases (cardiovascular, gastrointestinal, and respiratory), or drug use like steroids; that would interfere with the type of obesity and affect the normal growth of the children. Also, any child with a BMI between 85 and 95th percentiles (overweight) was excluded from the study. All participating obese children were suffering from exogenous simple obesity. They were classified according to their body mass index (BMI) percentiles into 72 obese (BMI ≥ 95th), and 39 control non-obese ones (BMI > 15th to < 85th), based on the Egyptian Growth Charts for children and adolescents. Ethical approvals were granted from both the Ethics Committee of the "National Research Centre" and the "Faculty of Postgraduate Childhood Studies" (Approval No. 17/125). Also, informed written consent was taken from either of the parents and assent from the participating children. They were subjected to blood pressure assessment, anthropometric measurements (weight [Wt], height [Ht], BMI, waist [WC], and hip [HC] circumferences), and laboratory evaluation (Visfatin, FGF-21, LDL, HDL, TG, cholesterol, fasting glucose, insulin, and calculation of HOMA-IR). Mann-Whitney test and Spearman's correlation test were applied. Obese children had significantly higher values than control ones regarding all the studied clinical (SBP, DBP), anthropometric parameters (Wt, Ht, BMI, WC, and HC), FBG, Insulin, HOMA-IR, Visfatin, and FGF-21, and had significantly lower values regarding HDL and Cholesterol. Among obese children, both FGF-21 and Visfatin had significant negative correlations with BMI and HC. At the same time, serum FGF-21 had a highly significant positive correlation with HDL. Visfatin and FGF-21 had highly significant positive correlations with each other. In the control group, both serum Visfatin or FGF-21 had insignificant correlations with each other and with all the studied clinical and anthropometric parameters. FGF-21 and Visfatin are related to the obesity markers, but they cannot be used as potential predictors for metabolic disturbance in obese prepubertal children; both had insignificant correlations with the metabolic risk factors.

Arginine-Stimulated Copeptin-Based Diagnosis of Central Diabetes Insipidus in Children and Adolescents

INTRODUCTION

Diagnosis of central diabetes insipidus (CDI) remains challenging. Water deprivation testing and hypertonic saline infusion, as established diagnostic tests, are mentally and physically demanding for patients. Arginine-stimulated copeptin has been shown as a putative parameter for the differential diagnosis of CDI in adults.

METHODS

In this single-centre retrospective study, we identified paediatric patients with suspected pituitary disorders who underwent standard arginine testing. Patients with CDI, matched controls, and primary polydipsia (PP) were identified. Diagnoses were confirmed retrospectively using comprehensive clinical and diagnostic characteristics. Serum copeptin concentrations were measured using a commercially available automated immunofluorescence assay (B.R.A.H.M.S Copeptin-proAVP KRYPTOR®) in samples stored for a median of 4.6 years (1.3-10.84) and collected before and 60 min after arginine infusion. Cut-off analyses were performed using ROC curves.

RESULTS

Serum samples from 32 patients with CDI, 32 matched controls, and 5 patients with PP (n = 69; 51 males, 18 females) were available for analysis. Median copeptin concentrations increased from 4.47 pmol/L (interquartile range [IQR]: 3.47-8.36) to 6.96 pmol/L (IQR: 4.51-12.89; p < 0.001) in controls, from 1.46 pmol/L (IQR: 1.21-2.12) to 1.44 (IQR: 1.10-1.87; p = 0.645, ns) in CDI, and from 4.40 pmol/L (3.95-6.33) to 9.58 pmol/L (8.19-11.42; p < 0.001) in PP. The published cut-off value of 3.8 pmol/L revealed a sensitivity of 100% and a specificity of 86.5% in confirming CDI.

CONCLUSION

Our results suggest that arginine-stimulated serum copeptin concentrations are a sensitive and specific diagnostic tool for CDI in paediatric patients, which may replace and simplify the conventional diagnostic pathway of water deprivation testing and hypertonic saline infusion.

Arginine-stimulated copeptin in children and adolescents

OBJECTIVE

Copeptin is secreted in isomolar amounts along with arginine vasopressin peptide (AVP) from the neurohypophysis. Its stability makes it a perfect candidate for the endocrine approach in the diagnosis of AVP deficiency (AVPD; cranial diabetes insipidus; CDI). However, pediatric reference values are lacking.

DESIGN AND PATIENTS

This is a monocentric retrospective analysis of donated residual serum samples from 72 children and adolescents who underwent arginine or growth hormone-releasing hormone-arginine stimulation to test GH secretory capacity from 2018 to 2022.

MEASUREMENTS

Copeptin was measured in baseline, 30-, and 60-min samples by BRAHMS Copeptin proAVP Kryptor immunofluorescence assay.

RESULTS

Of the 72 patients, 4 suffered from complete AVPD (CDI). The baseline level of copeptin in the 68 non-AVPD (non-CDI) patients was highly variable (range: 1.3-44.4 pmol/L). The increase after arginine was moderate (30 min range: 1.6-40.4 pmol/L). The median baseline and peak copeptin levels were 5.6 and 8.0 pmol/L, respectively. The 2.5th percentile of the baseline and peak values of copeptin were 2.1 and 3.3 pmol/L, respectively. The increase and peak value of copeptin were inversely related to age (R = -.405; p = .011, and R = -.335; p = .0072, respectively) but not to gender, body mass index (standard deviation score) or GH secretion. In the four patients with AVPD (CDI), baseline or stimulated copeptin was below the 2.5th percentile of non-AVPD (non-CDI) patients.

CONCLUSIONS

Stimulated copeptin is a promising parameter for the differential diagnosis of polyuria-polydipsia syndrome. However, the low copeptin increase after arginine and the high limit of quantification of the assay are problematic for use in paediatrics.

Combined Arginine and Insulin Stimulation Elicits a Robust and Consistent Copeptin Response in Short Children

INTRODUCTION

Copeptin, co-secreted with arginine vasopressin, is regulated by osmotic and volume stimuli but also responds to intravenous arginine and insulin-induced hypoglycemia. The serum copeptin response to the latter agents has been studied in adults but only to a limited extent in children. The objective of this study was to describe the copeptin response to combined arginine and insulin in children with normal posterior pituitary function.

METHODS

We conducted a prospective, single-arm assessment of serum copeptin concentrations in children (age 7-16 years, n = 38) undergoing growth hormone stimulation testing with an arginine-insulin tolerance test (AITT) for short stature or growth deceleration in a tertiary referral center. After overnight fasting, arginine (500 mg/kg) was administered between 0 and 30 min intravenously (IV) followed by insulin (0.1 units/kg IV) at 60 min. Copeptin serum concentrations were measured at baseline (0 min), at the post-arginine peak (60 min), and at the post-insulin peak (90 min; 30 min post-insulin), respectively. The main outcome was the peak copeptin concentration.

RESULTS

Mean ± SD copeptin concentrations increased from 9.9 ± 5.0 pmol/L at 0 min to 13.2 ± 5.8 pmol/L at 60 min (p < 0.0001 vs. 0 min) and 27.7 ± 14.2 pmol/L at 90 min (p < 0.0001 vs. 0 and 60 min). There was no significant correlation between copeptin concentrations and age, BMI, pubertal status, cortisol, growth hormone, or glucose concentrations.

DISCUSSION/CONCLUSION

Arginine and insulin appear to have an additive and consistent effect resulting in significant stimulation of copeptin secretion in children. The AITT may be a useful tool to evaluate for normal posterior pituitary function in this age-group, with potential implications for the evaluation of polyuria-polydipsia syndrome.

Approach to the Pediatric Patient: Central Diabetes Insipidus

Central diabetes insipidus (CDI) is a complex disorder in which large volumes of dilute urine are excreted due to arginine-vasopressin deficiency, and it is caused by a variety of disorders affecting the hypothalamic-posterior pituitary network. The differential diagnosis is challenging and requires a detailed medical history, physical examination, biochemical approach, imaging studies, and, in some cases, histological confirmation. Magnetic resonance imaging is the gold standard method for evaluating congenital or acquired cerebral and pituitary stalk lesions. Pituitary stalk size at presentation could be normal, but it may change over time, depending on the underlying condition, while other brain areas or organs may become involved during follow-up. Early diagnosis and treatment are crucial to avoid central nervous system damage and germ cell tumor dissemination and to minimize complications of multiple pituitary hormone defects. We provide a practical update on the diagnosis and management of patients with CDI and highlight several pitfalls that may complicate the differential diagnosis of conditions presenting with polyuria and polydipsia. The need for a careful and close follow-up of patients with apparently idiopathic CDI is particularly emphasized because the underlying condition may be recognized over time. The clinical scenario that we outline at the beginning of this article represents the basis for the discussion about how the etiological diagnosis of CDI can be overlooked and demonstrates how a water intake and urine output improvement can be a sign of progressive damage of both hypothalamus and anterior pituitary gland with associated pituitary hormonal deficiencies.

Serum copeptin as a biomarker of hypertension in children with obesity

BACKGROUND

Hypertension (HT) in obesity has been reported frequently in children in recent years. The role of copeptin and uric acid here are not well known. We aimed to investigate the relationship between HT and serum copeptin and uric acid levels in children with obesity.

METHODS

We included 80 children with obesity who were admitted to our hospital between April 2018 and September 2018. The patients were separated into two groups: hypertensive and non-hypertensive. Serum copeptin levels were measured using the enzyme-linked immunosorbent assay.

RESULTS

Copeptin levels were significantly higher in patients with HT than in those without (p = 0.0001). In addition, serum uric acid levels in patients with HT were significantly higher, while the serum potassium levels were significantly lower (p = 0.01) than in those without HT (p = 0.001). In correlation analyses, a positive correlation was detected between blood sodium and copeptin levels (p = 0.037).

CONCLUSIONS

Hypertensive children with obesity had higher serum copeptin and uric acid and lower blood potassium levels. Moreover, copeptin levels were positively correlated with blood sodium levels. Thus, in addition to copeptin, serum uric acid, potassium, and sodium levels may be important in the diagnosis and follow-up of children with HT.

Copeptin assays in children for the differential diagnosis of polyuria-polydipsia syndrome and reference levels in hospitalized children

OBJECTIVES

Polyuria-polydipsia syndrome (PPS) is a common presentation in children but the differential diagnosis rests on burdensome water deprivation tests. The aims of this study were to determine a copeptin threshold to distinguish patients with central diabetes insipidus from those with primary polydipsia and to estimate the normal range of copeptin concentrations in children.

DESIGN

Single-centre retrospective descriptive study.

PATIENTS

Two hundred and seventy-eight children aged 2 months to 18 years who consulted for PPS (N = 40) or other reasons (control group, N = 238) at La Timone University Hospital in Marseille, France, between April 2015 and September 2019 and had a copeptin assay.

MEASUREMENTS

Ultrasensitive copeptin assays on blood samples.

RESULTS

Among the children with PPS, the mean copeptin concentrations were 1.72, 55.2 and 15.7 pmol/l in those with central diabetes insipidus (N = 21), nephrogenic diabetes insipidus (N = 3), and primary polydipsia (N = 16), respectively. Copeptin levels lower than 3.53 pmol/l were diagnostic of central diabetes insipidus with 100% sensitivity and 87.4% specificity (p < .001). The 5th-95th copeptin percentile range in the control group was 2.53-21.03 pmol/L. Copeptin levels were significantly higher in boys than in girls but there was no association with age, pubertal stage, body mass index, or the reason for consulting.

CONCLUSIONS

Our results indicate copeptin assays may be valuable in the differential diagnosis of PPS in children. Larger prospective studies are required to establish their accuracy in everyday clinical practice.

A meta-analysis and trial sequential analysis of serum copeptin level in adult patients with Obstructive Sleep Apnoea Syndrome

OBJECTIVE

Copeptin can act as a stable biomarker in inflammation and stress response that obstructive sleep apnoea syndrome (OSAS), can induce oxidative stress and consequently promotes systemic inflammation. The purpose of the study is to appraise serum copeptin level in adult patients with OSAS compared to the controls.

MATERIAL AND METHODS

Electronic search was done in the databases of PubMed/Medline, Web of Science, Scopus, and Cochrane Library until June 2021, without any restrictions. For comparison of the serum copeptin level between groups, the mean difference (MD) and 95% confidence interval (CI) were calculated by the Review Manager 5.3 software. Trial sequential analysis (TSA) was used by applying TSA software.

RESULTS

Among the databases, five articles (involving 495 OSAS patients and 135 controls) were included. To report the serum copeptin level in OSAS patients compared to controls, the pooled OR became 12.21pg/mL (95%CI: 2.31 to 22.11; P=0.02) and also the pooled OR for comparison of serum copeptin level in severe versus moderate/mild OSAS patients was 5.96pg/mL (95%CI: 1.46 to 10.47; P=0.009). The results of TSA illustrated that the Z-curve has not crossed the monitoring boundary curves and did not reach the required information size.

CONCLUSIONS

The main findings recommended that copeptin had a significantly higher serum level in OSAS patients compared to controls, as well as a significantly higher level in severe patients compared to mild/moderate OSAS patients for the serum level of copeptin.

Novel molecular markers of cardiovascular disease risk in type 2 diabetes mellitus

Diabetes represents the leading risk factor for the development of cardiovascular disease (CVD). Chronic hyperglycemia and/or acute post-prandial changes in blood glucose determine an increase in reactive oxygen species (ROS), which play a fundamental role in endothelial dysfunction and in the nuclear transport of pro-atherogenic transcription factors that activate the "inflammasome". In addition, the glycemic alteration favors the formation and stabilization of atherosclerotic plaque through the mechanism of non-enzymatic glycation of different molecules, with the establishment of the so-called "advanced glycosylation end products" (AGE). Laboratory information provided by the level of biomarkers could make a quantitative and qualitative contribution to the clinical process of screening, prediction, prevention, diagnosis, prognosis and monitoring of cardiovascular (CV) risk linked to diabetes. This review describes the importance of specific biomarkers, with particular focus on novel ones, for stratifying and management of diabetes CV risk.