Women taking a combination of hormone therapy and calcium
and vitamin D tablets after menopause were less likely to fracture their hip
than those not taking hormones or supplements, in a new study.
"We always tell
women to take calcium and vitamin D," said Dr Michele Curtis, a women's
health researcher from the University of Texas Health Science Center at
Houston. "At the end of the day what this study really says is, what you
thought was a good thing to do really is a good thing to do."
Because of the known risks of hormone therapy, one of the
study's authors said women should not take it solely to ward off fractures –
but if they're taking hormones for other reasons, it might be a good idea to
Although many women take calcium and vitamin D for bone
health, evidence has been mixed on how much supplements really help over and
above what women get through their diets. In February, the government-backed US
Preventive Services Task Force said there were no benefits but some risk for
post-menopausal women taking low-dose vitamin D and calcium.
The group recommended
against supplement use to prevent broken bones. For the new study, Jean
Wactawski-Wende from the University at Buffalo and her colleagues compared
seven years' worth of fracture data for women in their 50s, 60s and 70s
participating in the Women's Health Initiative (WHI) study.
In one arm of the trial, participants were randomly assigned
to take either hormone therapy or a drug-free placebo. In another, they took 1 000
milligrams of calcium and 400 IU of vitamin D or placebo tablets each day.
About 16 000 women were part of both the hormone and vitamin trials, including
4 000 randomised to both hormone therapy – either oestrogen alone or oestrogen
and progesterone – and calcium and vitamin D.
Fractures dropped by 50%
In total, 214 women had a hip fracture during the study. The
researchers found that women assigned to both the hormone therapy and vitamin
groups were about half as likely to have a fracture as those in the placebo
groups. During an average one-year period, they calculated that 11 out of 10 000
women taking both hormones and calcium and vitamin D would suffer a hip fracture,
compared to 22 per 10 000 using neither.
combination treatment had no effect on women's bone mineral density – a
reflection of osteoporosis and fracture risk, Wactawski-Wende and her team
reported in the journal Menopause. Some previous studies have suggested that
vitamin D may protect against fractures less by strengthening bones than by
improving muscle strength and thereby reducing falls, but others have not found
the same effect.
Hormone therapy has become less common since WHI data linked
hormone use to heart disease, stroke and breast cancer, though it's still
considered the most effective treatment for some symptoms of menopause, such as
hot flashes. Curtis, who wasn't involved in the new research, said she thinks
the pendulum initially swung too far away from hormone therapy, and that
doctors are coming to realise it may still help some women.
"I think ultimately people have become aware that maybe it's
not the placebo for getting older that some may have perceived it was being
marketed as, but that maybe there are benefits for it," she told Reuters
Health. Because of the risks, women shouldn't take hormone therapy just to
prevent fractures," Wactawski-Wende said.
"The major indication for taking hormone therapy is for
management of moderate to severe menopausal symptoms," she told Reuters
Health. "However, those women who are on hormone therapy for vasomotor
symptoms, who may also get the benefit of prevention of fractures, should
consider supplementing with calcium at the same time to get the best
benefit," she said.