Article révisé par les pairs
Résumé : Introduction: Hyponatremia (HNA) is a common electrolyte disturbance associated with morbidity and mortality. The aim of this study was to assess incidence and prognosis value of HNA in the Emergency Department (ED). Methods: A retrospective observational case-control study has been conducted in the ED during 10 months. Control patients (Na 135-145 mmol/L) were matched, in a 1:1 ratio, on age, gender and month of ED admission with hyponatremic patients (Na < 130 mmol/L). Results: 256 patients (2.4 % of patients with a blood analysis) had HNA among which 166 were matched with 166 normonatremic controls. HNA patients had more often a history of asthma/chronic obstructive pulmonary disease (p = 0.002) and solid tumors (p = 0.001), received more diuretics (p = 0.026), and presented more often with vomiting (p = 0.034). Admission to the hospital or to the ICU was more frequent in HNA patients (89% vs. 52%, p < 0.001; 13% vs. 3%, p = 0.003, respectively). Patients with HNA presented more frequently at least one complication (digestive, septic, respiratory, renal, and cardiovascular) during their hospital/ICU stay (40% vs. 4%, p < 0.001). Mortality rate was higher in HNA than in controls (10% vs. 3%, p = 0.021). The multivariable conditional logistic regression analysis showed an independent association of HNA with solid tumors (OR = 4.12; 95 % CI: 1.68 to 10.1) and hospital death (OR = 2.90; 1.03 to 8.17). Conclusions: HNA was present in 2.4% of patients with a blood analysis and was associated independently with solid tumors and hospital death.