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

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 Würzburg, Würzburg, 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.

Effect of dulaglutide in promoting abstinence during smoking cessation: 12-month follow-up of a single-centre, randomised, double-blind, placebo-controlled, parallel group trial.

Background: Smoking cessation is challenging, despite making use of established smoking cessation therapies. Preclinical studies and one clinical pilot study suggest the antidiabetic drug glucagon-like peptide-1 (GLP-1) analogue to modulate addictive behaviours and nicotine craving. Previously, we reported the short-term results of a randomised, double-blind, placebo-controlled trial. Herein we report long-term abstinence rates and weight developments after 24 and 52 weeks. Methods: This single-centre, randomised, double-blind, placebo-controlled, parallel group trial was done at the University Hospital Basel in Switzerland. We randomly assigned (1:1) individuals with at least a moderate nicotine dependence willing to quit smoking to either a 12-week treatment with dulaglutide 1.5 mg or placebo subcutaneously once weekly in addition to standard of care smoking cessation therapy (varenicline 2 mg/day and behavioural counselling). After 12 weeks, dulaglutide or placebo injections were discontinued and the participants were followed up at week 24 and 52. The primary outcome of self-reported and biochemically confirmed point prevalence abstinence rate, and secondary outcome of secondary outcome of weight change were assessed at weeks 24 and 52. All participants who received one dose of the study drug were included in the intention to treat set and participants who received at least 10/12 doses of the study drug formed the per protocol set. The trial was registered at ClinicalTrials.gov, NCT03204396. Findings: Of the 255 participants who were randomly assigned between June 22, 2017 and December 3, 2020, 63% (80/127) (dulaglutide group) and 65% (83/128) (placebo group) were abstinent after 12 weeks. These abstinence rates declined to 43% (54/127) and 41% (52/128), respectively, after 24 weeks and to 32% (41/127) and 32% (41/128), respectively, after 52 weeks. Post-cessation weight gain was prevented in the dulaglutide group (-1.0 kg, standard deviation [SD] 2.7) as opposed to the placebo group (+1.9 kg, SD 2.4) after 12 weeks. However, at week 24, increases in weight from baseline were observed in both groups (median, interquartile range [IQR]: dulaglutide: +1.5 kg, [-0.4, 4.1], placebo: +3.0 kg, [0.6, 4.6], baseline-adjusted difference in weight change -1.0 kg (97.5% CI [-2.16, 0.16])), and at week 52 the groups showed similar weight gain (median, IQR: dulaglutide: +2.8 kg [-0.4, 4.7], placebo: +3.1 kg [-0.4, 6.0], baseline-adjusted difference in weight change: -0.35 kg (95% CI [-1.72, 1.01])). In the follow-up period (week 12 to week 52) 51 (51%) and 48 (48%) treatment-unrelated adverse events were recorded in the dulaglutide and the placebo group, respectively. No treatment-related serious adverse events or deaths occurred. Interpretation: Dulaglutide does not improve long-term smoking abstinence, but has potential to counteract weight gain after quitting. However, 3 months of treatment did not have a sustained beneficial effect on weight at 1 year. As post-cessation weight gain is highest in the first year after quitting smoking, future studies should consider a longer treatment duration with a GLP-1 analogue in abstinent individuals. Funding: Swiss National Science Foundation, the Gottfried and Julia Bangerter-Rhyner Foundation, the Goldschmidt-Jacobson Foundation, the Hemmi-Foundation, the University of Basel, the Swiss Academy of Medical Sciences.

Effect of dulaglutide in promoting abstinence during smoking cessation: a single-centre, randomized, double-blind, placebo-controlled, parallel group trial.

Background: Quitting smoking is difficult due to barriers such as craving for cigarettes and post-cessation weight gain. Recent experimental data suggest a role of glucagon-like peptide-1 (GLP-1) in the pathophysiology of addiction in addition to appetite regulation and weight control. We hypothesized that a pharmacological intervention with the GLP-1 analogue dulaglutide during smoking cessation may improve abstinence rates and reduce post-cessation weight gain. Methods: This is a single-centre, randomized, double-blind, placebo-controlled, parallel group, superiority study conducted in the University Hospital Basel in Switzerland. We included adult smokers with at least moderate cigarette dependence who wanted to quit. Participants were randomly assigned to a 12-week treatment with dulaglutide 1.5 mg once weekly or placebo subcutaneously in addition to standard of care including behavioural counselling and oral varenicline pharmacotherapy of 2 mg/day. The primary outcome was self-reported and biochemically confirmed point prevalence abstinence rate at week 12. Secondary outcomes included post-cessation weight, glucose metabolism, and craving for smoking. All participants who received one dose of study drug were included in the primary and safety analyses. The trial was registered on ClinicalTrials.gov (NCT03204396). Findings: Between June 22, 2017, and December 3, 2020, 255 participants were enrolled and randomly assigned to each group (127 in the dulaglutide group and 128 in the placebo group). After 12 weeks, 63% (80/127) participants on dulaglutide and 65% (83/128) on placebo treatment were abstinent (difference in proportions -1.9% [95% Confidence interval (CI) -10.7, 14.4], p-value (p) = 0.859). Dulaglutide decreased post-cessation weight (-1 kg [standard deviation (SD) 2.7]), while weight increased on placebo (+1.9 kg [SD 2.4]). The baseline-adjusted difference in weight change between groups was -2.9 kg (95% CI -3.59, -2.3, p < 0.001). Haemoglobin A1c (HbA1c) level declined on dulaglutide treatment (baseline-adjusted median difference in HbA1c between groups -0.25% [interquartile range (IQR) -0.36, -0.14], p < 0.001). Craving for smoking declined during treatment without any difference between the groups. Treatment-emergent gastrointestinal symptoms were very common in both groups: 90% (114/127) of participants on dulaglutide and 81% (81/128) on placebo). Interpretation: Dulaglutide had no effect on abstinence rates but prevented post-cessation weight gain and decreased HbA1c levels. GLP-1 analogues may play a role in future cessation therapy targeting metabolic parameters such as weight and glucose metabolism. Funding: Swiss National Science Foundation, the Gottfried Julia Bangerter-Rhyner Foundation, the Goldschmidt-Jacobson Foundation, the Hemmi-Foundation, the University of Basel, the Swiss Academy of Medical Sciences.

Copeptin is not useful as a marker of malignant disease in the syndrome of inappropriate antidiuresis.

OBJECTIVE: The syndrome of inappropriate antidiuresis (SIAD) is a common condition in hospitalized patients. It is crucial to establish the cause of SIAD, especially in order to exclude underlying malignancy. As malignant SIAD may be due to a paraneoplastic synthesis of arginine vasopressin, we hypothesized that its stable surrogate marker copeptin can be used as a diagnostic tool to differentiate between malignant and non-malignant SIAD. METHODS: Prospective observational study. We analyzed data from 146 SIAD patients of two different cohorts from Switzerland and Germany. Patients were included while presenting at the emergency department and underwent a standardized diagnostic assessment including the measurement of copeptin levels. RESULTS: Thirty-nine patients (median age: 63 years, 51% female) were diagnosed with cancer-related SIAD and 107 (median age: 73 years, 68% female) with non-malignant SIAD. Serum sodium levels were higher in cancer-related versus non-malignant SIAD: median (IQR) 124 mmol/l (120; 127) versus 120 mmol/l (117; 123) (P<0.001). Median (IQR) copeptin levels of patients with cancer-related SIAD were 11.1 pmol/l (5.2; 37.1) and 10.5 pmol/l (5.2; 25.2) with non-malignant SIAD (P = 0.38). Among different cancer entities, patients suffering from small-cell lung cancer showed the highest copeptin values, but overall no significant difference in copeptin levels between cancer types was observed (P = 0.46). CONCLUSIONS: Copeptin levels are similar in cancer-related and non-malignant SIAD. Therefore, Copeptin does not seem to be suitable as a marker of malignant disease in SIAD.