A number of pharmaceutical therapies are available to reduce plasma cholesterol, mainly LDL cholesterol. Therapies include the fat breakdown inhibitors, cholesterol absorption inhibitors, cholesterol synthesis inhibitors and bile acid binding resins. Each therapy varies in its individual effectiveness to lower plasma cholesterol and their related side effects. Statins work by inhibiting cholesterol synthesis and colestid works by binding bile acids in the intestine.
Plasma Lipids
Plasma cholesterol is associated with four major lipoprotein particles known as chylomicrons, VLDL, LDL and HDL. Chylomicrons are formed when lipids, including cholesterol and triglycerides, are absorbed from the intestine and transported via the bloodstream for utilization in the body. VLDL, or very low density lipoproteins, are made in the liver and carry cholesterol and triglycerides through the blood. LDL, or low density lipoproteins, are remnant particles of VLDL and form when the triglyceride is removed for energy needs. HDL, or high density lipoproteins, are the smallest lipoproteins and have the ability to carry cholesterol from arteries to the liver in a process known as reverse cholesterol transport.
Bile-Acid Binding Resins
Colestid is a bile acid binding resin that has been in use since the 1980s, and there are now newer bile acid binding resins with greater efficacy and fewer side effects. Colestid, and all bile acid binding resins, work by inhibiting the absorption and increasing the excretion of bile acids in the intestine. The liver then produces more bile acids from cholesterol, which subsequently reduces the amount of cholesterol in your plasma. A study in "The Annals of Pharmacotherapy" found that use of the bile acid binding resin colesevelam can lower your plasma LDL cholesterol by up to 20 percent.
Statins
Statins work by inhibiting cholesterol synthesis. The inhibition of cholesterol synthesis then requires cells to take up cholesterol from the blood, mainly in the form of LDL, to meet the daily requirements. A 2009 study in the journal "Circulation" showed that high statin therapy can reduce plasma LDL cholesterol by 48 percent. Statins are much more effective at lowering plasma cholesterol compared to colestid, but the side effects of statins are greater. The use of statins should be reserved for those patients who need the greatest reductions.
Combination Therapy
If you have extremely high plasma cholesterol, such as familial hypercholesterolemia, a combined therapy might be the best option. Combined therapies are commonly used when plasma cholesterol is not reduced to a satisfactory level with a single therapy. When you combine multiple cholesterol lowering therapies, you are able to even further reduce plasma cholesterol by taking advantage of the different modes of action. A 2001 study in the journal "Atherosclerosis" examined low dose combination therapy of statin and bile acid binding resin and found the combination therapy resulted in a 48 percent reduction in plasma LDL cholesterol. Reductions in plasma LDL cholesterol are similar to the reductions with high dose statin therapy, but have fewer side effect and are well tolerated.
References
- "The Annals of Pharmacotherapy"; Colesevelam Hydrochloride: a Novel Bile Acid-binding Resin; M.A. Aldridge, et al.; July 2001.
- "Circulation"; Effects of Statin Therapy According to Plasma High-sensitivity C-reactive Protein Concentration in the Controlled Rosuvastatin Multinational Trial in Heart Failure (Corona): a Retrospective Analysis; JJ McMurray, et al.; December 2009.
- "Circulation"; Coadministration of Colesevelam Hydrochloride with Atorvastatin Lowers Ldl Cholesterol Additively; D. Hunninghake, et al.; October 2001.
