DEAR DR. ROACH >> As a 73-year-old woman, I had a coronary calcium scan done when my new primary care physician wanted to start me on a statin. He discouraged me from having the scan done, saying it wouldn’t change his recommendation. I had tried three statins when I was in my 50s, and all of them caused muscle pain. I stopped each of them with my former doctor’s knowledge. My lipid panel showed that my total cholesterol was 263; HDL was 73; LDL was 150; triglycerides were 160; and ratio was 3.6. My coronary calcium scan showed a score of 128.

My total of 128 is in the range of 100-400, and put me in the 60th percentile and at “moderate to near future probability for a myocardial infarction.” Please explain what that means and how it’s possible that someone with a score of 128 can be in the same risk category as someone with a score of 399. The report seems serious, but with my history, I’m not sure I want to take a statin again.

— V.V.

Dear v.v. >> The coronary calcium score provides additional information about a person’s risk for developing a heart attack or dying of heart disease. Risk is usually given as the percentage of people who will have an event in the next 10 years.

There are many calculators to give a clinician and patient an estimate of risk, but none of the calculators are perfect. They use a subset of all the information available to provide a starting point, but a clinician uses additional information to adjust the risk provided by the calculator.

The MESA calculator (www.mesa-nhlbi.org/MESACHDRisk/MesaRiskScore/RiskScore.aspx) takes into account a person’s coronary calcium score, as well as some other traditional risk factors such as cholesterol, blood pressure and family history.

With the information you gave me, the calculator estimates your risk of a bad outcome in the next 10 years is 12.1%.

This calculator uses your exact number and doesn’t put people into categories the way your report did. If you had a calcium score of 399, for example, your 10-year risk would have been 16.2%. The positive family history changed your risk, too; it would have been 8.9% if you had no family history of heart attack.

At the level of 12.1%, the clear recommendation would be to take a statin. A statin would be expected to reduce your 10-year risk from 12.1% to roughly 9.7%. Unfortunately, you have had bad reactions to statins, and the decision to try a different one is up to you. There is certainly a benefit, but it is not a huge benefit.

Further, I have to disagree with your doctor. The calcium score definitely changed the recommendation. A calcium score of 0 would mean a 2.4% risk of a heart event in the next 10 years, so it clearly changes the recommendation about statins.

Sometimes the muscle aches attributed to statins are not due to statins. In one very powerful trial, people who reported muscle aches to statins were treated for a year: six months with a placebo and six months on a statin. Neither they nor their doctors knew what they were taking in any given month, and the pill they were given changed several times during the year. Every day, they marked down how much muscle pain they had. At the end of the year, the code was broken, and most people didn’t have worsened muscle aches during the times they were taking statins compared to the times they were taking the placebo.

Contact Dr. Roach at ToYourGoodHealth@med.cornell.edu.