Hyponatremia is a significant risk factor for minimal encephalopathy in patients with liver cirrhosis

Abstract

Backgrounds/Aims: The clinical significance of minimal hepatic encephalopathy is emphasized in cirrhotic liver patients since it not only affects quality of life but also disease prognosis. There are several studies showing correlation between hyponatremia and overt HE but none has been reported in MHE patients.Therefore we aimed to clarify the association between hyponatremia and MHE in cirrhotic liver patients.

Methods: Cirrhotic patients without overt HE were enrolled in this study. Laboratory tests including serum Na level and PHES were performed. MHE was defined as ≤-5 of PHES score. Hyponatremia was defined as serum Na level <135 mmol/L. The liver function was assessed by Child-Pugh classification and MELD score.

Results:A total of 176 patients with liver cirrhosis were enrolled in this study. Age was 55.5±8.5 years and male was 119 (67.6%).The most common cause of liver disease was chronic hepatitis B (70.5%), followed by alcoholic liver disease (18.2%) and chronic hepatitis C (6.8%). Child-Pugh score and MELD scores were 6.0±1.7 and 10.7±5.9, respectively, and 134 (76.1%)and 42 (23.9%) patients were classified as Child-Pugh grade A and B/C, respectively. Serum Na level was 139.2±3.1mmol/L. Hyponatremia was noted in 16 patients (9.1%) and its prevalence differed significantly according to the Child-Pugh grade: grade A, 3.0%; grade B, 19.4%; and grade C, 54.5%(P<0.001). PHES score was -3.1±3.5. PHES score differed significantly according to the Child-Pugh grade and hyponatremia. Forty-six patients (26.1%) were diagnosed as MHE. Hyponatremia ( β, 1.845; OR, 6.326; 95% CI, 1.780-22.473;P=0.004) and Child-Pugh grade B/C ( β, 1.232; OR, 3.428;95% CI, 1.521-7.726; P=0.003) were significantly associated factors with MHE.

Conclusions: Hyponatremia was significantly associated with MHE in patients with liver cirrhosis. Therefore,correction of hyponatremia is expected to/may improve MHE as well as quality of life.