Researchers at Johns Hopkins have determined that
screening for osteoporosis in men and women age 65 and
older can prevent a large number of hip fractures, a
debilitating, traumatic experience for 340,000 older adults
The researchers found that using a machine to estimate
bone density by measuring the tissues' ability to absorb
X-rays was associated with a 36 percent reduction in hip
fractures over six years compared with usual medical
The study, published in the Annals of Internal
Medicine on Feb. 1, is a unique look at the effects of
screening for osteoporosis in a general population,
studying 3,107 people from the Cardiovascular Health Study.
The CHS was designed to determine risk factors for
cardiovascular disease in community-dwelling older
"Although some groups recommend screening for
osteoporosis, no study had proven that screening prevents
fractures. This study provides new evidence for the
effectiveness of osteoporosis screening," said study lead
investigator Lisa Kern, a Robert Wood Johnson Clinical
Scholar at the Johns Hopkins School of Medicine at the time
of the study. Kern is now an assistant professor at the
Weill Medical College of Cornell University.
Co-investigator Neil Powe, director of Johns Hopkins'
Welch Center for Prevention, Epidemiology and Clinical
Research, said, "Our hope is that our study can provide
a foundation on which physicians can base their medical
practices regarding screening for osteoporosis and that it
can also be relevant to groups that are drafting clinical
guidelines on screening for osteoporosis."
According to Powe, there are two approaches to help
prevent osteoporosis-related fractures. One is to promote
measures that can prevent the disease itself via adequate
calcium and vitamin D intake, weight-bearing physical
activity and elimination of the use of tobacco and alcohol.
The second approach is to test for osteoporosis to help
identify people with low bone density and then plan
To assess the benefits of screening for osteoporosis,
the Johns Hopkins team studied 3,107 men and women, age 65
and older, who were participating in CHS from 1994 to 1995.
Participants already diagnosed with osteoporosis or a
previous hip fracture, and those taking bisphosphonate
drugs, were excluded. The study included people from
California, Pennsylvania, Maryland and North Carolina.
Participants in California and Pennsylvania had their bone
density measured locally, and the results were sent to
their primary care doctors. Subsequent treatment decisions
were left to the participants and their doctors. The
researchers followed study participants for up to six years
and collected information about hip fractures by using
The Johns Hopkins team found that hip fractures
occurred in 33 screened participants (about five fractures
per 1,000 person-years) and 69 usual-care participants
(about eight fractures per 1,000 person-years).
"This difference is statistically significant, but
there were some other differences between the groups that
can partially explain the variance in the incidence of hip
fracture," Kern said. "Surprisingly, differences in
prescription of vitamin D, calcium, estrogen and
bisphosphonates did not account for the entire difference
in hip fractures." The study did not collect information on
behavior changes, such as increased physical activity or
use of fall-prevention strategies, which might help account
for the benefit in people who were screened. Although the
study was not a randomized trial, it was the best available
way to evaluate the effectiveness of screening.
"It is hard to randomize persons into screened and
nonscreened groups today because Medicare now reimburses
for screening," said senior investigator Linda Fried,
director of Johns Hopkins' Center on Aging and Health. "Use
of medication to enhance bone density has increased over
the last 11 years, too, further making a randomized
evaluation difficult. Our study has several strengths but
should be useful to NIH consensus development panels and
groups drafting clinical guidelines on screening for
osteoporosis," she said.
Current estimates of the prevalence of osteoporosis
are 18 percent of women and 6 percent of men age 50 and
Funding for the study was provided by the National
Heart, Lung and Blood Institute; Robert Wood Johnson
Foundation; National Institute on Aging; and National
Institute of Diabetes and Digestive and Kidney Diseases.
Other researchers who took part in this study were Michael
Levine, Cleveland Clinic Foundation; Annette Fitzpatrick,
University of Washington, Seattle; Tamara Harris, National
Institute on Aging; and John Robbins, University of