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- <text id=90TT3025>
- <title>
- Nov. 12, 1990: When Bones Are Brittle
- </title>
- <history>
- TIME--The Weekly Newsmagazine--1990
- Nov. 12, 1990 Ready For War
- </history>
- <article>
- <source>Time Magazine</source>
- <hdr>
- MEDICINE, Page 82
- When Bones Are Brittle
- </hdr>
- <body>
- <p>Osteoporosis may take root in young women
- </p>
- <p> The crippling symptoms of osteoporosis have become almost
- synonymous with old age. The dowager's hump, the loss of height,
- the painful and often debilitating fractures of the spine and
- hip nearly always occur in elderly women after menopause (as
- well as in a smaller number of older men). And that age group
- has been the focus of prevention and treatment efforts.
- </p>
- <p> Now a controversial report suggests the disease often begins
- in younger women who have no outward sign of bone problems. The
- findings, reported last week in the New England Journal of
- Medicine by a team from the University of British Columbia,
- raise the possibility that more than half of all healthy women
- in their 30s and 40s could be suffering from bone damage as a
- result of subtle, undetected disturbances in their menstrual
- cycles. But some experts doubt the conclusions and call for
- follow-up trials before doctors change their approach to the
- disease.
- </p>
- <p> Bone, like many tissues, is constantly being broken down and
- rebuilt. In younger women this balance is thought to be
- maintained, at least in part, by the hormone estrogen. The
- sharply reduced production of estrogen after menopause, many
- researchers believe, upsets that balance, triggering a gradual
- loss of bone tissue. In about one-quarter of women, this
- deterioration eventually results in the porous, brittle bones
- characteristic of osteoporosis.
- </p>
- <p> In the new study, however, the researchers were not
- examining older women. Instead, they were trying to find out why
- one group of young women--marathon runners--seemed to be
- peculiarly predisposed to osteoporosis. The researchers
- theorized that disruptions in the runners' menstrual cycles
- might be at fault. But to their surprise, when they compared the
- marathoners with women who ran for recreation and others who
- engaged in no special physical activity, the researchers found
- that menstrual disturbances were common in all three groups.
- </p>
- <p> In fact, almost 30% of all cycles experienced by the 66
- women over a 12-month span were in some way disrupted. The upset
- was caused either by a failure to ovulate (or produce an egg)
- or by a shortened "luteal phase," a critical stage of the
- menstrual cycle during which the hormone progesterone is
- produced. More important the researchers found that these
- disturbances were directly related to dramatic bone loss: the
- 20% who missed ovulation at least once, for example, suffered as
- much as a 4% reduction in bone density in one year.
- </p>
- <p> How might menstrual problems hurt bones? Lead researcher
- Jerilynn Prior believes that reduced levels of the hormone
- progesterone--which was suppressed in women with cycle
- disruptions--may explain the damage. Some studies have
- indicated that this hormone helps with bone formation. Prior is
- not certain what causes the menstrual disturbances. The most
- likely candidate, she says, is stress.
- </p>
- <p> But other experts are skeptical. Dr. Charles Chesnut III,
- director of the Osteoporosis Research Center at the University
- of Washington, points out that it would be premature to draw
- major conclusions from such a short-term study. Longer trials
- are needed to show whether the bone damage is permanent.
- Besides, several experts contend, if such dramatic bone loss
- were in fact occurring in so many younger women, then it would
- have been obvious to doctors before now. If the study was
- exactly right, argues Chesnut, "most women would be entering
- menopause with no skeletons."
- </p>
- <p> Yet even if Prior's research overestimates the degree of
- bone damage in young women, the study is intriguing evidence
- that osteoporosis can at least get started at an early age. If
- that is confirmed, the information suggests that preventive
- steps--perhaps progesterone therapy--may help some women
- ward off the disease before it becomes crippling.
- </p>
- <p>By Andrew Purvis.
- </p>
-
- </body>
- </article>
- </text>
-
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