Decoding the importance of systolic and diastolic BP numbers

DEAR DR. ROACH: Decades ago, I served in the Marines and was wounded in action in the Korean War. While recuperating in the naval hospital, I was told by several doctors that the more important reading of blood pressure (which they took frequently) was the bottom number.

Now I am told by my doctors at the Veterans Affairs medical facility that it is the top number that is more critical. I am confused. Can you help? -- M.B.

ANSWER: Both the top number and the bottom number are important, and either of them might be more critical in any given person.

Looking at the entire population, it is thought that systolic blood pressure (the top number) is probably more associated with risk of heart attack and stroke. However, some people have normal systolic but high diastolic (the bottom number) pressures, and do need treatment.

Physicians can get clues about the underlying cause of high blood pressure from the readings. An older person with very high systolic and low diastolic pressure may have calcified, stiff blood vessels or a leaky valve connecting the heart with the aorta (the aortic valve).

A person with a low systolic and high diastolic may have some heart failure or may have a blockage in the aortic valve. Knowing more about an individual can help the doctor choose the best kind of medication.

I know it was decades ago, but I still thank you for your service.

DR. ROACH WRITES: A recent column about the side effects of statin drugs generated a lot of mail, mostly about alternatives to statin drugs in people who could not tolerate them.

I had mentioned in the column that a fourweek period of time off of statins followed by a trial of a different statin resulted in 60 percent of people being able to tolerate a statin.

One person wrote in that twice-a-week rosuvastatin (Crestor) was effective. However, some people cannot take them at all, and in that case, there are two options.

The first is a statin alternative. There are two classes that have been proven to reduce risk of heart disease: One, ezetimibe (Zetia), prevents absorption; the other is the PCSK-9 inhibitors, evolocumab (Repatha) and alirocumab (Praluent). The data on these drugs are not as strong as the data for statins.

Both classes are well-tolerated in most people. The PCSK-9 inhibitors are given by injection once or twice monthly and are very expensive.

The second option is non-drug therapy. Physicians don’t emphasize this as much as we should. There was a trial for a cholesterol-lowering drug where participants were required to meet with a nutritionist dietician then come back for retesting of their cholesterol after a period of maintaining a good diet.

Many potential subjects improved their cholesterol numbers so greatly that they were no longer eligible for the drug -- in fact, there weren’t enough people left to do the trial.

A mostly plant-based diet is so effective at improving cholesterol (and often helping with weight) that I feel physicians are frequently missing an opportunity to help our patients, with less risk of side effects and at less expense than medications. Combining a good diet with regular exercise is a dramatic combination that reduces risk not only of heart disease but many other diseases as well.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell. edu or send mail to 628 Virginia Dr., Orlando, FL 32803.