Which statement about bile acid sequestrants is true?

• A. They increase LDL
• B. They decrease triglycerides
• C. They improve mortality
• D. They decrease enterohepatic circulation of bile acids and lower LDL

Answer: (D)

Bile acid sequestrants work by binding bile acids in the gut, preventing their reabsorption and increasing their excretion in feces. This reduces the pool of bile acids returning to the liver (enterohepatic circulation). To replace the lost bile acids, the liver converts more cholesterol into bile acids, which lowers hepatic cholesterol content and upregulates LDL receptors on liver cells. With more LDL receptors available, more LDL cholesterol is pulled out of the bloodstream, leading to lower plasma LDL levels. This mechanism explains why the true statement emphasizes both a decrease in enterohepatic circulation of bile acids and a lowering of LDL. These drugs don’t reliably lower triglycerides, aren’t proven to improve mortality in major trials, and can cause GI side effects or interfere with the absorption of fat-soluble vitamins and other medications.