How to understand the risks of treatment when talking to your doctor

If your doctor prescribes a drug, recommends surgery or suggests any other form of treatment, you will naturally want to know the answers to a few specific questions, such as how well it works and whether the cure is worse than the disease. Your doctor should be able to offer you a clear idea of a treatment's potential benefits as well as its risk of side effects, preferably in the form of statistics from studies of patients who received the therapy. But those numbers can be tricky to interpret. Here are some tips on understanding the risks of treatment.

When a doctor tells you that a drug or procedure will reduce the risk that something bad will occur as a result of your condition, he may describe the drop in relative risk, that is, how much the risk will be reduced in someone who receives the therapy as compared to someone who does nothing.

• Studies have shown that widely prescribed cholesterol-lowering drugs called statins reduce the risk of heart attacks by 24 to 37 percent. Keep in mind that the likelihood of the average person having a heart attack in a given year is low. Reducing a five percent risk by 24 percent brings the risk down to about 3.75 percent.
•  When millions of people take a drug, small benefits like those add up, but that doesn't mean that you personally will see a benefit.
• If drugs were free and completely safe, none of this would matter much. But medications can be expensive and can cause serious side effects (such as liver and muscle damage in the case of statins). That's why it's important to have a serious discussion with your doctor about whether the benefit of a drug or procedure outweighs the risks.

You don't have to be a math whiz to talk statistics with your doctor.

Try asking questions a different way:

• "Out of 100 patients who have my condition, how many will recover if they take treatment A, treatment B or receive no treatment at all?"
•   "Of 100 patients who take the medication you're prescribing, how many will develop side effects?"

Talk with your doctor about whether the benefit of a drug or procedure outweighs the risks.

• If your doctor can't give you estimates, ask for his or her best informed opinion about how well the therapy works, then crosscheck it with another doctor or another source, such as a trusted website.