Sodium bicarbonate (NaHCO 3 ) prescription and extracellular volume increase: real‐world data results from the AlcalUN study

Julie Beaume (1) , Lucile Figueres (2) , Mickaël Bobot (3, 4) , Louis de Laforcade (5) , Hamza Ayari (6) , Thibault Dolley‐hitze (7) , Victor Gueutin (8, 9) , Antoine Braconnier (10) , Léonard Golbin (11) , Salvatore Citarda (12) , Guillaume Seret (13) , Lisa Belaïd (7) , Raphaël Cohen (6) , Yosu Luque (14, 15) , Fabrice Larceneux (16) , Riyad N.H. Seervai (17) , Camille Overs (18) , Jean‐philippe Bertocchio (8)

1 HIA - Hopital d'instruction des armées Sainte-Anne [Toulon]
2 CHU Nantes - Centre Hospitalier Universitaire de Nantes
3 C2VN - Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research
4 LA CONCEPTION - Hôpital de la Conception [CHU - APHM]
5 Centre Hopitalier Pierre Oudot [Bourgoin-Jallieu]
6 HEGP - Hôpital Européen Georges Pompidou [APHP]
7 AUB Santé
8 CHU Pitié-Salpêtrière [AP-HP]
9 AURA Paris - Plaisance
10 Hôpital universitaire Robert Debré [Reims]
11 Centre Hospitalier Universitaire de Rennes [CHU Rennes] = Rennes University Hospital [Ponchaillou]
12 Calydial - Centre associatif lyonnais de dialyse
13 Association ECHO [Expansion des Centres d’Hémodialyse de l’Ouest]
14 CHU Tenon [AP-HP]
15 CoRaKID - Maladies rénales fréquentes et rares : des mécanismes moléculaires à la médecine personnalisée
16 DRM - Dauphine Recherches en Management
17 BCM - Baylor College of Medicine
18 CHUGA - Centre Hospitalier Universitaire [CHU Grenoble]

Oral alkalization with sodium bicarbonate (NaHCO3) or citrate is prescribed for conditions ranging from metabolic acidosis to nephrolithiasis. While most nephrologists/urologists use this method routinely, extracellular volume (ECV) increase is the main feared adverse event reported for NaHCO3. Thus far, no trial has specifically studied this issue in a real-world setting. AlcalUN (NCT03035812) is a multicentric, prospective, open-label cohort study with nationwide (France) enrollment in 18 (public and private) nephrology/urology units. Participants were adult outpatients requiring chronic (>1 month) oral alkalization by either NaHCO3-containing or no-NaHCO3-containing agents. The ECV increase (primary outcome) was judged based on body weight increase (ΔBW), blood pressure increase (ΔBP), and/or new-onset edema at the first follow-up visit (V1). From 02/2017 to 02/2020, 156 patients were enrolled. After a median 106 days of treatment, 91 (72%) patients reached the primary outcome. They had lower systolic (135 [125, 141] vs. 141 [130, 150], p=0.02) and diastolic (77 [67, 85] vs. 85 [73, 90], p=0.03) BP values, a higher plasma chloride (106.0 [105.0, 109.0] vs. 105.0 [102.0, 107.0], p=0.02) at baseline, and a less frequent history of nephrolithiasis (32 vs. 56%, p=0.02). Patients experienced mainly slight increases in blood pressure (ΔBP<10 mmHg). The primary outcome was not associated (p=0.79) with the study treatment (129 received NaHCO3, 27 received citrate). We subsequently developed 3 different models of propensity score matching; each confirmed our results. Chronic oral alkalization with NaHCO3 is no longer associated with an ECV increase compared to citrate in real-life settings.

Mots clés: sodium bicarbonate; potassium citrate; nephrolithiasis; kidney diseases; extracellular volume

Domaines: Sciences pharmaceutiques

Julie Beaume, Lucile Figueres, Mickaël Bobot, Louis de Laforcade, Hamza Ayari, et al.. Sodium bicarbonate (NaHCO 3 ) prescription and extracellular volume increase: real‐world data results from the AlcalUN study. Clinical Pharmacology and Therapeutics, 2021, 111 (1), pp.252-262. ⟨10.1002/cpt.2427⟩. ⟨hal-03366548v1⟩