MEDICINE

Brittle bones

Reporting a new treatment for osteoporosis

DIANE BRADY July 23 1990
MEDICINE

Brittle bones

Reporting a new treatment for osteoporosis

DIANE BRADY July 23 1990

Brittle bones

MEDICINE

Reporting a new treatment for osteoporosis

After Laura Harris began to experience pain in her spine four years ago, her doctor diagnosed the London, Ont., woman as having osteoporosis, a condition in which a hormonal deficiency and the aging process cause the victim’s bones to diminish and become dangerously brittle. Her doctor added that there was little he could do to help. Said Harris, now 68: “He had me thinking I’d be in a wheelchair before long.” Although injections of parathyroid hormone and another hormone called calcitonin helped Harris avoid that fate, she has suffered several small spinal fractures. Now, tests carried out in the United States have raised the prospect that a drug that has been used since 1978 to treat Paget’s disease can also reverse some of the effects of osteoporosis, a debilitating illness that afflicts Harris and more than 800,000 other Canadians.

In a study published last week in the highly regarded New England Journal of Medicine, researchers from seven U.S. universities reported that patients treated alternately with

etidronate and calcium over a two_

year period had 50 per cent fewer fractures than those who just took calcium pills. The nationwide trial, which involved 429 women with osteoporosis who had suffered spinal fractures, confirmed the results of a smaller Danish study released in May.

The new findings, said Dr. Nelson Watts, associate professor at the Emory University School of Medicine in Atlanta, a member of the research team, could make etidronate the “drug of choice” in treating osteoporosis. That affliction affects more than 15 million Americans and is blamed for 1.3 million fractures annually. The condition is particularly common among older women, because after menopause their bodies produce less estrogen, the female sex hormone that plays a crucial role in maintaining healthy bone tissue.

The report by Watts’s group said

that among the osteoporosis sufferers tested, etidronate increased bone mass in the spine and reduced by 50 per cent the incidence of new spinal fractures in women treated with the drug, compared to the members of a control group who were given a placebo, or inert drug. But, while the study found that etidronate increased bone mass in the spinal area, it failed

to produce significant improvement in participants’ hips or wrists.

Although the U.S. study focused on women who already have osteoporosis, some doctors said that there may be a role for etidronate in preventing the condition. Dr. Jonathan Adachi, an associate professor of medicine at the McMaster University medical school in Hamilton and president of the Osteoporosis Society of Canada, said that women’s bones seem to weaken after their ovaries stop producing high levels of estrogen. As a result, some postmenopausal women have successfully used estrogen supplements to ward off osteoporosis. Still, Adachi said that many women are reluctant to take estrogen because of a suspected link to breast cancer and because estrogen can cause menstruation to resume. Adachi recommended further studies “with younger ladies to see if we can prevent fractures in the first place.”

In fact, the Canadian sub-

lt; sidiary of Norwich, N.Y.g based Norwich Eaton Pharii maceuticals Inc., which § manufactures etidronate and

funded the U.S. and Danish “ studies, says it wants to £ launch a study this fall that, g like the American survey, o would test the effects of eti“■ dronate on older women with

osteoporosis. The new study will be directed by Dr. Eugene Cameron, an associate professor at the University of British Columbia medical school. Etidronate, which Procter & Gamble Co. first developed in the mid-1960s, has been used for the past 12 years to treat Paget’s disease of the bone, an illness that causes a cycle of rapid bone formation and deterioration in three per cent of the population over the

Meanwhile, some doctors suggested that the effects of etidronate on people with osteoporosis need further study. In an editorial in the New England Journal accompanying the Watts study, Lawrence Riggs, an osteoporosis expert at the Mayo Clinic in Rochester, Minn., called the drug “a welcome new option,” but questioned whether it could have damaging effects on bone strength or bone-cell activity. For her part, Dr. Joan Harrison, a professor of medicine at the University of Toronto, said that the U.S. study was “promising but not conclusive. We need longer trials and comparison with other drugs.” Still, for Laura Harris and others suffering from osteoporosis, etidronate may offer hope of relief from a debilitating

and painful condition.

DIANE BRADY