The levels of bilirubin may be related to an inflammatory condition in patients with coronary heart disease

In agreement with previous reports, we found that the bilirubin level is significantly lower in the blood of patients with coronary heart disease (CHD) than in age and sex matched controls. However, we found that the level of bilirubin in the blood seemed to be an age-dependent phenomenon and closely related to the activation of leukocytes. In 1,000 cardiac catheterised patients from Urbana, USA suffering from CHD, the level of blood bilirubin was found to be lower than in age and sex-matched controls. The same results were obtained on 300 patients with acute ischemia from three hospitals from Bucharest, Romania. The activation of polymorphonuclear leukocytes increased in the catheterised patients, as well in Romanian patients. An activation of leukocytes triggered by a chronic inflammatory process may increase the lysis of erythrocytes. The erythrocytes of patients with 100% stenosis exhibited a higher rate of in vitro lysis in the presence of activated leukocytes and homocysteine. The increased hemolysis may trigger the activation and removal of the resulting bilirubin from blood. Such a mechanism may depend on the liver clearing function. This function was decreased in catheterized patients over 60 years of age, but had accelerated in younger patients. An individual variation in liver function may explain the widespread bilirubin levels in the blood of patients suffering from CHD.