The nurse is reviewing the client’s laboratory values. Which serum laboratory value indicates to the nurse that a prescription for atorvastatin is having the desired effect for a client at risk for coronary artery disease?

Choice A reason: Low-density lipoprotein (LDL) is often referred to as “bad” cholesterol because high levels can lead to plaque buildup in arteries and result in heart disease and stroke. Atorvastatin is a statin medication that works by reducing the production of cholesterol in the liver, specifically targeting LDL cholesterol. Lowering LDL levels is a primary goal in managing and reducing the risk of coronary artery disease. Choice B reason: High-density lipoprotein (HDL) is known as “good” cholesterol because it helps remove other forms of cholesterol from the bloodstream. While atorvastatin can also help increase HDL levels, the primary indicator of its effectiveness in reducing the risk of coronary artery disease is the reduction in LDL levels. Choice C reason: Prothrombin time (PT) is a measure of how long it takes blood to clot. It is not directly related to the effectiveness of atorvastatin in managing cholesterol levels or reducing the risk of coronary artery disease. PT is more relevant in the context of anticoagulant therapy. Choice D reason: Creatine phosphokinase (CK) is an enzyme found in the heart, brain, and skeletal muscles. Elevated CK levels can indicate muscle damage, which can be a side effect of statin therapy. However, CK levels are not used to measure the effectiveness of atorvastatin in lowering cholesterol or reducing the risk of coronary artery disease.