Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00390741 |
| Other study ID # |
H-20834 |
| Secondary ID |
NIA R37 AG09901 |
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
October 1998 |
| Est. completion date |
September 2005 |
Study information
| Verified date |
January 2022 |
| Source |
University of Maryland, Baltimore |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The major goals of this study are:
1. To conduct an intervention development study to evaluate the feasibility of implementing
an exercise intervention for reduction losses in bone mineral density, muscle mass, and
strength, and clinically relevant aspects of functioning following a hip fracture, and
to obtain preliminary tests of the effective ness of these interventions.
2. To evaluate the effect of home-based exercise intervention on bone metabolism.
3. To evaluate the effects of hip fracture on bone metabolism.
4. To evaluate the effects of exercise and hip fracture on hormonal regulators.
5. To evaluate the association between markers of bone metabolism hormone regulators, and
BMD.
6. To separate out the effects of hip fracture on bone turnover from those of aging in
persons with low bone mineral density.
Description:
Hip fracture is a major public health problem, with striking consequences for the older
patient, her family and the health care system. More than 350,000 persons over age 65 will
fracture a hip in the United States during the coming year at an estimated annual cost of
over $12 billion; by 2040, over 650,000 hip fractures will occur annually in this group.
Between 18-33% of older hip fracture patients die within one year of their fracture,
depending upon the specific population studied. Most surviving hip fracture patients
experience reduced mobility and lose their ability to function independently. As many as 45%
of those who are community dwelling at the time of their fracture are discharged to
institutions post-hospitalization, and 15-25% remain institutionalized for a year
post-fracture. Further, significant strain is observed in over a third of family caregivers
as long as a year post-fracture. Depending upon the population studied and function being
assessed, an estimated 25-75% of those who are independent before their fracture can neither
walk independently nor achieve their previous level of independent living within a year
following their fracture and 10- 20% of those who sustained a hip fracture can expect to have
another osteoporotic fracture within two years.
This protocol consists of two components related to the recovery after hip fracture
(described below):
EXERCISE INTERVENTION TRIAL. With few exceptions, which are restricted primarily to studies
of comprehensive in-patient rehabilitation, little systematic attention has been given to
evaluating strategies for improving functioning, bone, and muscle post-hip fracture.
Strategies that have been shown to improve bone, muscle, and function in older persons who
have not fractured a hip may be useful if applied to persons following hip fracture. Exercise
is one of the strategies that have received considerable attention. Exercise training in
older adults also has beneficial effects on bone density, muscle strength, and physical
functioning, as well as cardiovascular fitness, and risk reduction for falls and fractures.
An exercise program that combines weight-bearing and resistance exercises can increase bone
mineral content in postmenopausal women. Little information is available on whether a
home-based exercise program can be used to achieve similar benefits compared to a more
structured, on-site exercise program. This issue is particularly relevant in older, frail
women who have sustained a hip fracture because many are unable and unwilling to travel to
exercise facilities.
Results of the studies of exercise are instructive of potential benefits for older persons
following hip fracture. Most of the work to date has been restricted to relatively healthy,
select samples of older persons who have been recruited into rigorously controlled randomized
experiments. Hence, while they are efficacious in benefiting a select group of older persons,
it is not known whether these interventions will be accepted by a frail older population
which has become suddenly disabled by a hip fracture, nor is it known whether these
interventions will be beneficial to this group which is losing bone, muscle and function at
an accelerated rate.
Because losses in BMD following hip fracture place these women at greater rise of subsequent
fracture and may delay or prevent full recovery of ambulatory ability, it is important to
optimize fracture healing and prevent loss of bone. One therapeutic option for these patients
that may be effective is to increase physical activity through exercise.
Despite these profound losses in function, bone, and muscle, we remain uncertain about the
extent to which these losses can be attributed to the fracture, and only limited attention
has been given to preventing such losses. In addition, we seek to understand the role of
exercise in relation to bone metabolism and levels of hormones thought to regulate bone
metabolism following a hip fracture. Elucidating these mechanisms will be valuable for
understanding the effects of exercise on bone health. The purpose of this study is to take an
intervention known to be beneficial in select populations, into the real world setting and
apply to frail older persons who have become suddenly disabled by a hip fracture. It is
essential to test the effectiveness of the intervention following a hip fracture.
With a waiver for authorization obtained at each hospital, the study nurse will do a chart
review of hip fracture patients to determine study eligibility and then explain the study to
the potential participant, obtain consent, and get baseline study measures within fifteen
days of fracture. The project coordinator will notify the exercise trainers of which
participants have been randomized to the treatment group, and the trainer will set up the
first home visit.
After completing the baseline interview the participant will be assigned to one of two study
groups. One group is the treatment group and one involves no treatment and are followed as
usual care. Those assigned to the treatment group will be visited by an exercise trainer who
will visit the participant three times a week for the first two months of the study, two
times per week during months three and four, one time per week during months five and six,
two times a month during months seven and eight, and one time a month during months nine
through twelve. During months seven through twelve of the study the trainer will contact the
participant by telephone once each week during the weeks that he or she does not go the
participants' home.
Follow-up interviews, performance assessment, DEXA scans, ultrasound measurements (only for
34 participants) and blood draws will be done at two, six and twelve months following hip
fracture. The baseline and follow-up interviews will last approximately two hours.
NON-HIP FRACTURE COMPARISON. Bone loss that occurs in older women is believed to result from
uncoupling of bone remodeling. Despite the loss of BMD with aging, the cellular mechanisms
for fracture healing appear to remain intact. Fracture healing can be divided into three
phases: inflammatory, reparative, and remodeling. The first two phases are dependent
primarily on the local trauma effects of the fracture and are completed within approximately
five weeks; hence, exercise intervention would be expected to have little or no effect on
these processes. The remainder of the approximately six-month duration of femoral neck
fracture healing involves modeling and remodeling of the callus. Because skeletal loading may
modulate remodeling, exercise should have an effect during this period. Even after completion
of healing, mechanical factors are expected to continue to affect remodeling of the femur.
Bone resorption, mediated by osteoclastic activity, is the first phase of a remodeling cycle.
In the post-fracture context, in which both fracture debris removal and callus remodeling are
ongoing, high levels of markers of resorption would be anticipated.
We will attempt to separate out the effects of hip fracture on bone turnover from those of
aging in persons with low bone mineral density. Bone turnover of hip fracture patients
receiving usual care will be compared to bone turnover in a similar group of women who have
not fractured their hips (i.e., matched on age, ability to ambulate independently, and with
low BMD).
