Hypercholesterolemic patients demonstrate a submaximal oxygen transport rate, University of Minnesota researchers report in a study published in the
Henry Buchwald and his team analyzed blood samples from 100 patients and uncovered an inverse correlation between plasma cholesterol levels and oxygen transport rate — a measure of how efficiently oxygen can be moved out of red blood cells and into the tissues. "Doctors have noted that chest pain associated with coronary heart disease diminishes after cholesterol is lowered," said Buchwald. The team conclude that plasma cholesterol level is a controlling factor in erythrocyte membrane cholesterol content, which in turn regulates oxygen transport in and out of red blood cells, and thereby, tissue oxygen availability. Therefore, high plasma cholesterol levels lead to overly high amounts of cholesterol in the membranes of red cells, which hinders the movement of oxygen out of those cells and into tissues.
"The findings suggest it would be simpler, safer and far less expensive to test the oxygen transport rate in a small sample of the patient's blood instead of a cardiac stress test, which is sometimes invasive," said Buchwald. In addition to establishing the presence or absence of heart disease, measurement of the oxygen transport rate can also be important in evaluating other diseases, such as diabetes. The team also highlighted other potential applications of the measurement, such as in assessing nonpathologic conditions such as athletic potential or overall health.