Low serum total thyroxine and free triiodothyronine in patients with hepatic encephalopathy due to non-alcoholic cirrhosis.

Abstract

We evaluated serum thyroid hormone levels in non-alcoholic cirrhotic patients with and without hepatic encephalopathy. 15 consecutive patients with hepatic encephalopathy secondary to non-alcoholic cirrhosis (8 males and 7 females, age 37-75 years) and 33 non-alcoholic cirrhotic patients without encephalopathy (22 males and 11 females, age 36-74 years) were investigated. A control group consisted of 20 healthy subjects (10 men and 10 women aged 26-69 years). The levels of serum triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH), free T3 (FT3) and free T4 (FT4) were studied in serum samples drawn in the morning. Thyroid function tests were set in relation to the severity of hepatic dysfunction and to the presence or absence of hepatic encephalopathy. Serum levels of FT3 and total T4 (but not total T3 and FT4) were significantly lower in patients with hepatic encephalopathy compared to decompensated cirrhotic patients without encephalopathy (p = 0.006 for T4, P <0.05 for FT3). Prothrombin-time also differed significantly between decompensated cirrhotic patients (Child C) with and without encephalopathy groups (p = 0.002). These results suggest that patients with hepatic encephalopathy secondary to decompensated non-alcoholic cirrhosis are typified by low FT3 and low total T4, as well as by a prolonged prothrombin time. Low FT3 does not obviously put patients at risk for hepatic encephalopathy, and thyroid parameters are secondary and late events.