ASK THE DOCTOR: Osteoporosis: No bones about it
By DR JIM MITTERANDO

Q - I am 61 years old. Should I have a bone density test for osteoporosis and take calcium pills?

A - Diagnosing and treating osteoporosis (thin bones) is somewhat controversial with many opinions and not much long-term data.

Everybody's bones weaken as they age, but certain choices and habits accelerate the process. These include:

• Inactivity
• Not getting enough calcium and vitamin D
• Smoking
• Drinking too much alcohol
• Using certain medications, such as steroids like prednisone or certain seizure medications.

Prevention: use it or lose it

Weight-bearing exercise, such as walking or running, helps maintain bone strength. Studies in astronauts show bone loss occurs rapidly in zero-gravity. Regular exercise by the astronauts prevented bone loss. For the rest of us back on Earth, this means we need to use our bones and muscles more regularly. Weight-training programs also help.

Calcium and vitamin D

Most adults do not get enough calcium and this leads to the body breaking down bone where calcium is stored. Adults under age 50 need 1,000 mg daily and 1,200 mg after age 50. Ideally, calcium should come from your diet. Dairy products such as milk, yogurt and cheese typically provide about 300 mg of calcium per serving. Calcium supplements are recommended (especially after age 50) if you are not getting enough from your diet. The type of supplement does not matter. Calcium carbonate is the cheapest. Coral calcium makes no difference other than it costs more and is the latest fad. Calcium is better absorbed if taken with food or milk. You should only take 500 or 600 mg at a time since you cannot absorb more than this amount.

Antacid medicines can decrease calcium absorption. Contrary to past warnings, people with kidney stones can take calcium. Drinking soda will not cause osteoporosis as long as you get enough calcium. People who drink soda are less likely to drink enough milk and get the recommended daily requirement of calcium.

Vitamin D can help calcium absorption. It is found in milk and your body makes it when exposed to sunlight. The recommended amount of vitamin D is 400 IU. Some experts recommend 800 IU, especially in older people who do not get as much sunlight and may not absorb calcium as well.

Bone density

Osteoporosis is defined as decreased bone density (calcification) that increases a person's risk for fracture. ‘‘Osteopenia'' describes milder thinning of the bone that is a common finding on bone density tests. Osteopenia is not a disease and in fact 50 percent of women over age 50 have osteopenia. Osteopenia is not associated with fractures and does not require prescription medications.

Screening

Women 65 and over should consider bone densitometry screening. Women at high risk (family history of osteoporosis, early menopause, or chronic steroid use) should consider bone density testing at 60. Women with vertebral fractures or who have lost more than 2 inches in their height should also consider screening.

DEXA scan is the preferred bone density test. No routine blood test is commonly accepted for screening. Ultrasound tests are not considered accurate. Routine bone density testing for men is not recommended since osteoporosis is not as common.

Treatment

Slow bone loss and reduce the change of bone fractures with more exercise, calcium and vitamin D.

Costly prescription medications are available. However, the goal of these medications is to prevent fractures, not build bone strength.

The most common medications used to treat osteoporosis are alendronate (Fosamax) and risedronate (Actonel). They prevent bone breakdown but do not build new bone nor stimulate the growth of new bone. Estrogen is not recommended because long-term risks outweigh benefits. Soy has no effect on bone density. Raloxifene (Evista) is an estrogen-like drug that can help prevent vertebral fractures but short-term studies show no effect in preventing hip fractures. This medicine can also increase the risk of blood clots and cause hot flashes. Calcitonin and parathyroid hormone are not effective in preventing fractures. Statin cholesterol drugs (Lipitor, etc.) have had conflicting data whether they benefit bone density and require long-term testing.

Dr. Jim Mitterando is a family doctor at Cohasset Family Practice and a staff member at South Shore Hospital in Weymouth.

Readers should send questions to: Ask the Doctor, The Patriot Ledger, P.O. Box 699159, Quincy, MA. 02269-9159, or by E-mail to his attention at features@ledger.com.

Questions of general interest will be answered in this column. The information in this column is not intended to diagnose individual conditions, and individual replies are not possible. Readers should see their own doctors about specific problems.

Copyright 2004 The Patriot Ledger
Transmitted Tuesday, November 23, 2004