title: High serum osmolarity at admission determines a worse outcome in patients with heart failure: Is a new target emerging?
abstract: OBJECTIVE
  The osmolarity of human serum is restricted to a tightly regulated range, and any deviation has clinical implications. Our aim in this study was to establish whether differences in serum osmolarity in heart failure (HF) patients are related with a worse outcome.
  
  
  METHODS
  We evaluated the prognostic value of serum osmolarity in patients with HF from the Spanish National Registry on Heart Failure (RICA), a multicenter, prospective registry that enrolls patients admitted for decompensated HF and follows them for 1year. Patients were divided into quartiles according to osmolarity levels. Primary endpoint was the combination of all-cause mortality and hospital readmissions for HF.
  
  
  RESULTS
  A total of 2568 patients (47.46% men) were included. Patients with higher osmolarity were older, presented more comorbidities (especially diabetes mellitus and chronic kidney disease), and consequently had higher levels of glucose, urea, creatinine and potassium. During the 1-year follow-up, mortality among the quartiles was 18% (Q1), 18% (Q2), 23% (Q3) and 28% (Q4), p<0.001. After adjusting for baseline characteristics, high serum osmolarity was significantly associated with all-cause mortality (RR 1.02, 95% CI 1.01-1.03, p<0.001). We also found a significant increase in the combined endpoint of mortality and readmission among quartiles with higher osmolarity (p<0.001). Diabetes, eGFR, Barthel index, systolic blood pressure, body mass index, hemoglobin, NYHA class and beta-blocking agents were also independently associated with the primary endpoint.
  
  
  CONCLUSIONS
  In patients admitted for decompensated HF, high serum osmolarity predicts a worse outcome, and is associated with a higher comorbidity burden, supporting its use as a candidate prognostic target in HF.
authors.affiliation: Internal Medicine Service, Zafra County Hospital, Ctra Badajoz-Granada s/n. 06300, Zafra, Spain. Electronic address: joscarlor@gmail.com.
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Arévalo-Lorido
authors.affiliation: Internal Medicine Service, Zafra County Hospital, Ctra Badajoz-Granada s/n. 06300, Zafra, Spain.
authors.forename: Juana Carretero
authors.initials: JC
authors.lastname: Gómez
authors.affiliation: Internal Medicine Service, University Hospital of Bellvitge, Feixa Llarga, s/n, 08907 L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Formiga
authors.affiliation: Internal Medicine Sevice, University Hospital of Gran Canaria Dr. Negrin, Barranco de la Ballena, s/n, 35010 Las Palmas de Gran Canaria, Las Palmas, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Conde-Martel
authors.affiliation: Internal Medicine Service, Hospital of Soria Santa Bárbara, P° de Santa Bárbara, s/n, 42005, Soria, Spain.
authors.forename: Margarita
authors.initials: M
authors.lastname: Carrera-Izquierdo
authors.affiliation: Internal Medicine Service, Hospital of León, Altos de Nava s/n. 24071, León, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Muela-Molinero
authors.affiliation: Internal Medicine Service, University Hospital Nuestra Señora de la Candelaria, Ctra. Gral. del Rosario, 145, 38010 Santa Cruz de Tenerife, Spain.
authors.forename: Melitón Francisco
authors.initials: MF
authors.lastname: Dávila-Ramos
authors.affiliation: Internal Medicine Service, Hospital Municipal de Badalona, Via Augusta, 9-13, Badalona, Barcelona, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Serrado-Iglesias
authors.affiliation: Internal Medicine Service, University Hospital "Ramón y Cajal", Ctra. de Colmenar Viejo, Km. 9,100, 28034 Madrid, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Manzano-Espinosa
authors.affiliation: Internal Medicine Service, University Hospital Reina Sofia, Av. Menéndez Pidal, s/n, 14004 Córdoba, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Montero-Pérez-Barquero
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D010343:Patient Admission / Q000639:trends*; D011446:Prospective Studies; D012042:Registries; D044967:Serum / Q000378:metabolism*; D016896:Treatment Outcome
keywords: Congestive heart failure; Hyponatremia; Osmolarity