Prognostic role of hypochloremia in acute ischemic stroke patients

The impact of electrolyte imbalance on clinical outcomes after acute ischemic stroke (AIS) is still not understood. We investigated the association between hypochloremia and hyponatremia upon hospital admission and in-hospital mortality in AIS patients.

A total of 3314 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included in this study. Hypochloremia was defined as having a serum chloride concentration <98 mmol/L and hyponatremia as having a serum sodium concentration <135 mmol/L. The Cox proportional hazard model was used to examine the effect of hypochloremia and hyponatremia on all-cause in-hospital mortality in AIS patients.

During hospitalization, 118 patients (3.6%) died from all causes. Multivariable model adjusted for age, sex, baseline National Institutes of Health Stroke Scale score, serum sodium, and other potential covariates showed that hypochloremia was associated with a 2.43-fold increase in the risk of in-hospital mortality (hazard ratio [HR] 2.43; 95% confidence interval [CI], 1.41-4.19; P=.001). However, no significant association between hyponatremia (P=.905) and in-hospital mortality was observed. Moreover, the multivariable analysis found that serum chloride (HR=0.92, 95% CI 0.88-0.98; P=.004) but not serum sodium (P=.102) was significantly associated with in-hospital mortality.

Hypochloremia at admission was independently associated with in-hospital mortality in AIS patients.