"Unexpected" Increase in Thrombosis Risk Seen With Strenuous Exercise
in Elderly  CME

http://www.medscape.com/viewarticle/572521

News Author: Anthony J. Brown, MD
CME Author: Désirée Lie, MD, MSEd

April 4, 2008 -- Elderly individuals who engage in strenuous exercise,
such as jogging, are at heightened risk for venous thrombosis compared
with their sedentary peers, according to the results of a new study.
Still, the authors assert, the benefits of moderate or strenuous
exercise in elderly individuals likely outweigh this risk.

Prior observational studies have yielded conflicting results regarding
the impact of exercise on the risk of venous thrombosis, according to
the report in the Journal of the American Geriatrics Society for
March. However, the main studies investigating this topic did not
provide a detailed analysis of exercise, or careful control of
potential confounding factors.

The current investigation by Dr. Susan R. Heckbert of the University
of Washington, Seattle, and colleagues, involved an analysis of data
for 5534 subjects, 65 years and older, without prior venous
thromboembolism who were enrolled in the Cardiovascular Health Study
and were followed for a median of 11.6 years.

Self-reported exercise was assessed two or three times during follow-
up. "The amount of exercise was categorized in three different ways,"
the investigators explain: as exercise versus no exercise based on a
minimum expenditure of 500 kcal/week; as kilocalories expended per
week; and as none or mild, moderate, or strenuous in intensity.

Exercise intensity was graded using metabolic equivalent levels.
Activities with a metabolic equivalent (MET) level below 4, like
walking, were considered low intensity. Gymnastics and other
activities with a MET level of 4 to 6 were classified as moderate
intensity. Activities with a MET level above 6 were classified as
strenuous, such as jogging.

During follow-up, 171 patients developed a first venous thrombosis,
the report indicates.

After adjusting for gender, age, race, self-reported health, and body
mass index, exercise at baseline was not a significant predictor of
venous thrombosis. However, when exercise was modeled as a time-
varying exposure, there was a suggestion of an elevated thrombosis
risk.

Further analysis showed a nonsignificant reduction in thrombosis risk
with mild-intensity exercise, such as walking, with an adjusted hazard
ratio of 0.75. By contrast, jogging and other strenuous activities
increased the risk of venous thromboembolism significantly (adjusted
HR = 1.75) relative to no exercise at all.

Despite these findings, Dr. Heckbert and colleagues conclude: "The
overall benefits of exercise likely outweigh the possible higher risks
of venous thrombosis or injuries, but more research is needed to
investigate this unexpected higher risk of venous thrombosis in
elderly people associated with strenuous-intensity exercise."

J Am Geriatr Soc. 2008;56:517-522.

Clinical Context
The incidence of venous thrombosis is 1 to 3 per 1000 persons per
year, and the rate increases with age with rates as high as 10 per
1000 in elderly people. Although physical exercise may be expected to
lower the risk for venous thrombosis, the evidence from trials is
controversial, with some showing a reduced risk for venous thrombosis
with increased exercise and some showing increased risk vs no
exercise.

This is an observational cohort study of community-dwelling
participants aged 65 years or older from 4 US counties during a period
of almost 12 years to examine the association between self-reported
exercise and venous thrombosis risk in older persons.

Study Highlights
Included were 5201 participants aged 65 years or older from 4
communities and a minority cohort of 687 African American participants
from 3 of the 4 communities.
The community sample was drawn from the Medicare eligibility list.
Excluded were those who used a wheelchair, were receiving hospice or
chemotherapy and were not expected to survive, and those with a
baseline self-reported history of venous thrombosis.
Follow-up occurred by telephone calls and clinic visits every 6
months.
Hospitalizations were identified by self-report, proxies, and a search
of the Health Care Financing Administration records using the
International Classification of Diseases, Ninth Revision, Clinical
Modification discharge codes.
A definite diagnosis of deep vein thrombosis required a positive
result on duplex ultrasonography, venography, or other diagnostic
test.
A definite diagnosis of pulmonary embolism required a ventilation-
perfusion scan or pulmonary angiogram.
Definite and probable diagnoses were considered together for the
analysis.
A trained interviewer assessed exercise, race, self-reported health,
weight change, activities of daily living (ADL), and instrumental ADL
during the preceding year.
Weight and height were measured.
Questionnaires recording physical activities were administered at
baseline and after 3, 4, and 7 years of follow-up.
At each exercise assessment, participants were asked about the type,
frequency, and intensity of activities within the preceding 2 weeks
and the number of months that activities were performed.
Participants were specifically asked about a spectrum of activities
for exercise including walking, household chores, cycling, dancing,
aerobics, jogging, bowling, and swimming.
Average kilocalorie expenditure per week was calculated and intensity
scores assigned depending on the reported usual pace.
Exercise intensity was based on MET intensity levels.
A total of 5534 participants had no history of venous thrombosis at
baseline and were followed up for a median of 11.6 years.
During the follow-up, 171 participants developed a first venous
thrombosis.
At baseline, 37.6% were classified in the exercise group based on
expending 500 kcal or more of exercise per week, and 62.4% were
classified in the nonexercise group, based on expending less than 500
kcal per week.
Participants in the exercise group were younger, more likely to be
men, lean, less likely to be black, and had better self-reported
health.
Exercise at baseline was not associated with risk for venous
thrombosis after adjustment for age, race, sex, self-reported health,
and body mass index.
With exercise modeled as a time-varying exposure, findings were in the
direction of higher risk associated with exercise (hazard ratio [HR],
1.38), and adjustment for confounders did not alter the finding.
When analysis was restricted to healthy individuals, the HR for venous
thrombosis was 1.99.
The greater risk for venous thrombosis associated with exercise was
not related to cancer and was similar for idiopathic as for secondary
venous thrombosis.
Mild-intensity exercise was associated with a slightly but not
significantly lower risk for venous thrombosis (HR, 0.75).
Strenuous exercise and exercise expending more kilocalories vs no
exercise was associated with increased risk for venous thrombosis with
an HR of 1.46.
Pearls for Practice
Physical exercise in older individuals is associated with increased
risk for venous thrombosis.
In older adults, the increased risk for venous thrombosis associated
with physical exercise is greater in those who engage in strenuous
exercise expending more calories.

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Phytate from our foods has been shown to be a standin for etidronate.

Theoretically these phytate rich foods will standin for .. exercise ..
for osteoporosis

Hmmm ... eating versus .. exercise.

Inactivity versus Brisk Walking and Gymnastic Training

Am J Phys Med Rehabil. 2002 Jun ;81 (6):452-7 12023603
Beneficial effect of etidronate on bone loss after cessation of
exercise in postmenopausal osteoporotic women.
[My paper] Jun Iwamoto , Tsuyoshi Takeda , Shoichi Ichimura
OBJECTIVES:
To determine whether etidronate could prevent or restore bone loss
after cessation of exercise in postmenopausal osteoporotic women.
DESIGN:
Thirty-five postmenopausal osteoporotic women were studied. Exercise
consisted of daily brisk walking and gymnastic training. The changes
in the lumbar bone mineral density measured by dual energy x-ray
absorptiometry were assessed.
RESULTS:
One or two years of exercise increased the bone mineral density from
the baseline. One year of cessation of exercise after 1 yr of
exercise
resulted in the loss of the bone mineral density gained through
exercise. Two years of cyclical etidronate treatment from year 2
sustained the bone mineral density during 2 yr of cessation of
exercise in the preventative etidronate treatment group and
completely
restored the loss of bone mineral density after 1 yr of cessation of
exercise in the therapeutic etidronate treatment group.
CONCLUSIONS:
Cyclical etidronate treatment, when exercise is discontinued, seems
to
be beneficial for the prevention or restoration of bone loss after
cessation of exercise in postmenopausal osteoporotic women. Although
the present study has a small sample size, the results may be
interesting, especially because they raise additional questions that
could stimulate further research.
Mesh-terms: Aged; Bone Density, drug effects; Case-Control Studies;
Densitometry, X-Ray; Etidronic Acid, therapeutic use; Exercise;
Female; Human; Middle Aged; Osteoporosis, Postmenopausal, drug
therapy;

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You know there seems to be a bisphosphonate found in your .. grub.

Phytate / phytic acid .. found in the chaff of your grain and in your
plants compared to .. etidronate.

http://tinyurl.com/2wuhuk

Who loves ya.
Tom

Jesus Was A Vegetarian!
http://tinyurl.com/2r2nkh

Man Is A Herbivore!
http://tinyurl.com/a3cc3

DEAD PEOPLE WALKING
http://tinyurl.com/zk9fk