LISA CLARK: Welcome to our webcast. I'm Lisa Clark. The connections between osteoporosis and menopause or calcium levels are common knowledge to doctors and patients alike, but fewer people know about the so-called "secondary causes of osteoporosis." Certain medical conditions and even some medications have been shown to increase a person's risk of osteoporosis.
Joining me today to discuss these risk factors is Dr. Martin Nydick, an endocrinologist at the New York Presbyterian Hospital, Cornell Campus in New York City. Dr. Nydick, thank you for being here.
MARTIN NYDICK, MD: Thank you for inviting me.
LISA CLARK: To go over it for people who are unfamiliar with osteoporosis, the basic mechanism is a natural loss of bone in the body that may occur because of what kinds of factors?
MARTIN NYDICK, MD: The major factor is the loss of estrogen at menopause. That is far and away the biggest cause of osteoporosis. There are other factors, such as inheritance of poor bones, a family history of osteoporosis, and certain lifestyle abnormalities, such as alcohol and cigarette smoking, but estrogen loss is the major cause.
On the other hand, when I see a patient with osteoporosis, I always look for a secondary cause. In other words, I don't say, "Oh, she's menopausal, therefore it's due to estrogen deficiency," because a goodly percentage of our patients do turn out to have another cause that may be hidden, such as taking corticosteroids for rheumatoid arthritis or asthma, or taking thyroid medication. But we also see patients who have hyperparathyroidism, where the parathyroid glands in the neck are overactive, we see patients with malabsorptions of calcium and vitamin D, and that can be very, very tricky to pick up.
LISA CLARK: Sometimes, someone with a digestive problem may not be absorbing the calcium?
MARTIN NYDICK, MD: Yes, exactly. They may think that they have lactase deficiency, which is a very common thing where we can't absorb the lactose in milk, but they may actually have a low-grade form of sprue, which is an intestinal inflammation that can cause malabsorption of various nutrients. I see quite a few patients with that. So we're always looking for a secondary cause, just to be sure that we aren't missing something before we take it for granted that it's just postmenopausal.
LISA CLARK: Now one of the things that surprised me when I read it, one of the medications that might be a suspect are antacids that contain aluminum. Now, you see a lot of antacids marketed as calcium sources, but there's a specific type that may actually cause a calcium depletion?
MARTIN NYDICK, MD: Yes. Aluminum is actually a poison to the bones, particularly in people with renal disease. We used to see this when we used a lot of aluminum in the dialysis fluid. These people can get severe bone disease. In normal people who don't have renal disease, it probably isn't a factor unless they're taking very large amounts of aluminum-containing antacids.
LISA CLARK: Now are the secondary causes of osteoporosis more common in certain groups of people? Are there certain patients who will come in with possible osteoporosis and you would say they're suspects?
MARTIN NYDICK, MD: Because estrogen deficiency isn't a problem in men, in men we see more secondary causes of osteoporosis.
LISA CLARK: That's logical.
MARTIN NYDICK, MD: Perhaps 50 percent of the men who have osteoporosis tend to have a secondary cause, so we will always look much more deeply in those men.
LISA CLARK: Do you find male patients resistant to the notion that they might have osteoporosis because it's believed to be a disease that affects elderly women more often?
MARTIN NYDICK, MD: Absolutely, absolutely. Just the other day, I was seeing a woman with osteoporosis and she came in with her little husband, who was all bent over, and I said, "You should have a bone density," and he refused.
LISA CLARK: Very interesting. But it never hurts to talk to your doctor, no matter what your gender or your age?
MARTIN NYDICK, MD: That's right.
LISA CLARK: Thank you so much for being with us, Dr. Nydick. We appreciate your time.