Measurement of daily cholesterol synthesis rates in man by assay of the fractional conversion of mevalonic acid to cholesterol.

A significant correlation has been found in man between total daily cholesterol synthesis rates as determined by sterol balance measurements and the fraction of intravenously administered R-[5-14C]mevalonic acid converted to cholesterol. In 30 studies it was found that the mean daily cholesterol synthesis rates estimated by sterol balance measurements ranged from 395 to 3047 mg/day, whereas the fractional conversion of mevalonate to cholesterol varied from 0.28 to 0.99. The two parameters correlated with a coefficient of 0.87, P less than 0.001. This method for estimating cholesterol synthesis rates requires low doses of radioisotopic materials (25 muCi of [14C]mevalonate and 5 muCi of [3H]cholesterol) and less than 1 hr of the patient's time; it can be repeated at intervals of 3 weeks and reflects cholesterol synthesis over a short period of time.