Saturday, January 19, 2008

Now calcium?

Gotta stay light on the feet these days when it comes to advice. Hormones? Depends. Zetia? Fuhgeddaboutit. Calcium? Maybe not... especially for the elderly.

New Zealand investigators asked 1,471 old ladies (average age 74) to take calcium citrate, 1000 mg/day, or not, and then checked out who suddenly pitched over dead (as in cardiac arrest), had a heart attack (MI), or suffered a stroke in the five years following. Their primary intention, actually, was to prove once again that calcium supplementation improves bone density, but they also theorized that it might improve cardiovascular health as well.

Wrong. In the final analysis, the old gals on calcium had double the risk of MI, 1.4 times the risk of stroke, but no increased risk of sudden death. When all these endpoints were combined, the cardiovascular risk from the recommended dose of calcium each day was increased 1 and 1/2 times over the unsupplemented group. Looked at another way, doctors would need to treat 50 old ladies with calcium to prevent one symptomatic fracture over 5 years, 44 to cause one MI, 56 to cause one stroke, and 29 to cause one cardiovascular event.

What are they saying about this one?

Dr Erin D Michos, Johns Hopkins University: This is a thought-provoking study, although not definitive, but further work should be done.

Judy O'Sullivan, British Heart Foundation: Anyone who has been advised by their doctor to take calcium supplements to protect their bones should not stop doing so in light of this study alone without medical advice.

Dr. Ian Reid, senior author on paper: What we think is happening is that the higher calcium intake—and particularly the bolus of calcium that supplementation provides—is somehow accelerating the laying down of calcium in the artery walls of the heart...The way I interpret this is that if you have preexisting heart disease—which probably most of our participants did, although they probably weren't aware of it—then the extra calcium appears to be bad. But if, on the other hand, you are 54 and you have nice clean arteries to your heart, then probably calcium is not going to cause you any major problems. That's my take on it. But I don't know if it can be proven.

What am I going to do? Just like most of my patients, I find calcium tablets big and gross. Sometimes I take them, sometimes I don't. I plan to keep up that strategy and advise my patients of the above information. If I was even older than I am, I think I'd leave my calcium tablets on the shelf and face up to yogurt, vitamin D, and exercise.

7 comments:

Ruth said...

Very interesting! There really is no pill to replace a good diet and health habits.

Anonymous said...

I'm glad to read this! I also find calcium tablets big and gross. I'm going to try harder to get enough calcium from milk and yogurt.

Beverly said...

It seems like for every good something is for us, there will also be a bad effect in it too...We can't win...I am on heparin (Fragmin) and should take the horse pills, but I think yogurt will do for now.

Mauigirl said...

I think I'll stick to 3-4 helpings of dairy a day (low fat of course) and the occasion Tums!

denverdoc said...

Ruth, Laura, and MG, I'm with you. Going to make a better effort on diet, even though yogurt is almost as creepy as big, gross calcium tablets.

Beverly, it does seem when medical science takes a good thing (calcium) and elevates it to a pharmocological intervention, some bad effect follows. Like Celebrex and COX 2 inhibition--less inflammation, cancer protection, but, whoops, increased risk of cardiovascular disease. Does Fragmin cause loss of bone density?

Anonymous said...

OK, this is good, I'm with you on the pills (Ugh).However, having become lactose intolerant, I have lactaid on my cereal and that's about it for dairy. Broccoli is a fave, but what else?

Anonymous said...

I try to pay attention to what I eat & get enough calcium from food, but I, too, have my calcium supplement.

Loved to learn I'm not the only one who "sometimes I take them, sometimes I don't."

I try to drink calcium-fortified OJ and other juices; wonder if this is as 'bad', in terms of the New Zealand study mentioned, as taking supplements?