Evidence map›Paper›PMID 39639680›Full record

ArticleClinical endocrinology2025

Redefining Diagnostic Cut-Offs for the Indirect Water Deprivation Test.

Yash Akkara, Kavita Narula, Katharine Lazarus, Deborah Papadopoulou, Sirazum Choudhury, Niamh Martin, Karim Meeran

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Article in Clinical endocrinology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Arginine Vasopressin Deficiency and Oxytocin Deficiency in the Endocrine Clinic.The Journal of clinical endocrinology and metabolism · 2026
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Yash AkkaraDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.ORCID http://orcid.org/0009-0002-5193-3639
Kavita NarulaDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.
Katharine LazarusDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.ORCID http://orcid.org/0000-0003-0758-7839
Deborah PapadopoulouDepartment of Endocrinology, Imperial College Healthcare NHS Trust, London, UK.
Sirazum ChoudhuryDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.ORCID http://orcid.org/0000-0003-2429-005X
Niamh MartinDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.ORCID http://orcid.org/0000-0003-1185-2762
Karim MeeranDivision of Diabetes, Endocrinology and Metabolism, Department of Metabolism Digestion and Reproduction, Imperial College London, London, UK.ORCID http://orcid.org/0000-0002-7112-2756

Funding

This work was supported by the National Institute for Health Research (NIHR), the NIHR Imperial Clinical Research Facility, and NIHR Imperial Biomedical Research Centre at Imperial College Healthcare NHS Trust.
6 · The paper itself

Abstract

objectiveAn incorrect diagnosis of arginine vasopressin deficiency and resistance (AVP-D and AVP-R) results in the potentially dangerous use of desmopressin in healthy individuals. The water deprivation test is a central diagnostic test in patients with polydipsia polyuria syndrome (PPS). This study aims to determine the effectiveness of the current interpretation of reference ranges.

methodsThis is a retrospective analysis of 135 patients who underwent a water deprivation test between August 2014 and August 2023. All patient diagnoses were reviewed, and variability and receiver operating characteristic (ROC) curves were determined for serum osmolality, serum sodium and urine osmolality.

resultsSerum sodium demonstrated reduced variability compared with serum osmolality (0.72% vs. 1.16%, respectively, 37.5% reduction; p < 0.001). The standard serum osmolality cut-off value of ≥ 300 mOsm/kg in diagnosing AVP-D, AVP-R, and primary polydipsia (PP) achieved a sensitivity of 76.19% and specificity of 76.92%. A serum sodium cut-off value of ≥ 148 mmol/L demonstrated 100% specificity in excluding PP. This cut-off was used alongside urine osmolality cut-off values of > 630 mOsm/kg (for PP) and < 383 mOsm/kg (for AVP-D/AVP-R). Review of post-desmopressin urine osmolality and clinical monitoring was performed in equivocal diagnostic cases (n = 6), achieving 100% sensitivity and 100% specificity within the study sample.

conclusionsThis study demonstrates that a serum sodium cut-off of ≥ 148 mmol/L in tandem with urine osmolality yields the best diagnostic accuracy to differentiate between AVP-D, AVP-R, and PP. Serum sodium may be more reliable than serum osmolality in the investigation of patients with PPS, demonstrating lower biological and analytical variability.

Indexed as

SodiumWater DeprivationAdolescentAdultAgedArginine VasopressinFemaleHumansMaleMiddle AgedOsmolar ConcentrationPolydipsiaPolyuriaReference ValuesRetrospective StudiesROC CurveArginine VasopressinSodiumdynamic function testingosmolalitysodiumvasopressin deficiencywater deprivation test

Identifiers

PMID39639680
PMCPMC11694560

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.