Atrial fibrillation leads to stroke

DEAR DR. ROACH: I was diagnosed with atrial fibrillation in July 2017. A week after that, I had an MRI that showed I’d had a ministroke and probably several others in the past.

I love ribeye steak, and eat it maybe two or three times a year. Is this safe?

ANSWER: Atrial fibrillation is a rhythm problem of the heart. The natural rhythm is lost, so the heartbeat becomes irregular.

Because of the lack of normal movement in the heart, the blood can pool and form clots in the left atrium; these clots can travel downstream to lodge in a blood vessel.

Clots can cut off the blood supply to the area where they lodge. It’s most critical when it happens in the brain, since if brain cells die, function is lost.

A stroke is just a focal area of cell death in the brain. The size and location of the area in the brain where cell death occurs determines how significant the stroke is. Strokes can range from unnoticeable to devastating to fatal. Most people with atrial fibrillation take medication to reduce the risk of stroke.

Eating poorly can increase the risk of heart disease and stroke as well, but most commonly this happens via a different mechanism.

High amounts of saturated fat — such as in ribeye steak, which is fattier than many cuts of beef — increase the risk of damage to blood vessels through buildup of cholesterol plaques.

These plaques cut off blood supply, and this causes a heart attack if the plaques are lodged in the arteries of the heart, a stroke if in the brain and various problems if in other parts of the body. In people who have a history of stroke, it’s particularly important to take steps to reduce further risk. That means a discussion with your doctor about whether you are on the best treatment for atrial fibrillation and whether you have evidence of cholesterol plaques.

Even if you don’t have any evidence of plaques, a healthy diet of mostly plants, with whole grains, nuts and seeds, some fatty fish if you enjoy that and sparse amounts of meats reduces many health risks.

However, two or three steaks a year is not going to cause harm. The best data available shows that people who have 100 grams (just over 3 ounces) of red meat a week are at the lowest risk of developing blood vessel problems. It’s not clear that zero is better than that small amount.

In any event, I am a firm believer that enjoying life is the goal. If having a steak a few times a year is truly enjoyable, the risk is small, and you should enjoy those meals without guilt.

DEAR DR. ROACH: I used to have chronic constipation. A couple of months ago, when I had a cold, I started using a throat lozenge containing zinc. After a few days, I noticed I was having “easy” bowel movements. When I stopped taking the zinc, the constipation reappeared.

I read that too much may not be good for you, so now I take half of a 50-mg tablet every other day. It is like a miracle. Maybe this can help others.

ANSWER: I’m not a big believer in zinc for colds, as the data showing benefit are not convincing and there are side effects. However, diarrhea is a known side effect, so it’s not surprising that zinc might help your constipation.

Excess zinc can cause problems, but at the dose you are taking, getting an excess is very unlikely.

Not all zinc is absorbed, and it may be that the zinc and the fluid it takes with it act like magnesium, another possible treatment for constipation.

DEAR DR. ROACH: I’m 85 years old. I have numbness in my hands — sometimes the right, sometimes the left; sometimes both hands or not at all. It lasts only a while. My doctor feels that it’s a pinched nerve in my neck. Can you give me any advice?

ANSWER: A pinched nerve in the neck becomes more prevalent as people age. The nerve can be compressed by bony structures in people with osteoarthritis in the neck (this is spinal stenosis), or by disk material in someone with a herniated disk.

Having symptoms on both sides is less common than having symptoms consistently on one side only. A careful physical exam can give clues that this is the case, but an MRI or other imaging study is the best way to be sure of the diagnosis.

Hand numbness also may be caused by the nerve being “pinched” in other locations: in the carpal tunnel in the wrist or in the cubital tunnel in the elbow.

An EMG test can help sort out where this is coming from. It’s certainly possible to have carpal tunnel syndrome on both sides.

My best advice is not to rush into surgery at any age, but especially not at age 85. Physical therapy can prevent many people from needing surgery. However, if numbness progresses to weakness, it’s time to reconsider.

Readers may email questions to ToYourGoodHealth@med.cornell.edu.