Pravastatin has no effect on bile lipid composition, nucleation time, and gallbladder motility in persons with normal levels of cholesterol.

Abstract

Pravastatin dissolves gallstones in patients with hypercholesterolemia by reducing the cholesterol saturation index (CSI) of bile. There are few reports on effect of pravastatin on bile lipids, CSI and nucleation time (NT) in patients with gallstones and normal plasma lipid levels, or on the effect of pravastatin on gallbladder motility. Therefore we studied the effect of pravastatin on bile lipids, CSI, NT, and gallbladder motility in persons with normal cholesterol levels. We included 10 patients (ages 32 +/- 8 years; 6 men) with symptomatic gallstones and normal plasma lipid profiles. Estimation of bile lipids, CSI, and NT in duodenal bile and gallbladder motility were done using standard methods. Subsequently each patient was given 40 mg pravastatin daily for 1 month. At completion of pravastatin therapy, bile lipids and gallbladder motility studies were repeated. After pravastatin therapy, we found no significant reduction in bile cholesterol (11.2 +/- 3.2 vs. 10.4 +/- 2.8 mmol/l), bile acids (114.6 +/- 7.4 vs. 133 +/- 16 mmol/l), phospholipids (23 +/- 3.5 vs. 24 +/- 6.2 mmol/l), CSI (1.28 +/- 0.4 vs. 1.22 +/- 0.3), and nucleation time (7 +/- 3 vs. 7 +/- 3 days). In addition, there was no significant change in gallbladder fasting volume (26 +/- 3 vs. 26.6 +/- 3 ml), residual volume (14.6 +/- 1.1 vs. 15.08 +/- 1.4 ml), ejection fraction (44% vs. 43%), and rate constant of gallbladder emptying (0.018/min vs. 0.022/min). One-month therapy with pravastatin does not alter bile lipids, CSI, NT, and gallbladder contractility in persons with normal levels of cholesterol.