I know there are studies showing that high cholesterol levels are predictors of heart disease, stroke and heart attacks. Are there studies that show lowering cholesterol with medications reduces those outcomes? — R.M.

Answer: Yes and no. The answer depends on how high a person’s risk is and what treatment is used to reduce the cholesterol.

Before you consider medications, know that lifestyle treatments — especially diet and exercise — can have immense benefits in reducing heart disease risk, with no chance of medication side effects and with many additional benefits, including a lowered risk of many cancers. Physicians are often eager to start medicines and not eager enough to give people the information and motivation to make healthy lifestyle changes.

In someone with known coronary artery disease (the type of disease caused by atherosclerosis of the arteries to the heart, leading to blockages in the arteries and often to a heart attack), lowering the cholesterol has been shown to reduce the risk of a heart attack or stroke in many different studies.

The best data comes from studies on statin drugs, but ezetimibe (Zetia) and the PCSK-9 inhibitors (given by injection) also have proven benefit. An older class of drugs, the fibrates, are still sometimes used, but do not have the abundance of data showing effectiveness.

In people without known blockages, only those who are at high risk have been proven to have a reduced risk of heart disease and stroke. High blood pressure, very high total and LDL cholesterol levels, very low HDL levels and a strong family history all increase risk, but a decision to use medications must take into account a person’s overall risk and the risk of these medications’ side effects.

Men are at a higher risk than women (age and all other risk factors equaling out), but heart disease remains the leading cause of death in women — and women are systematically undertreated in North America.