The relationship between exercise and risk of venous thrombosis in elderly people.
OBJECTIVE
To study whether exercise is associated with the risk of venous thrombosis in elderly people.


METHODS
Observational study with a median follow-up of 11.6 years.


METHODS
The Cardiovascular Health Study in four U.S. communities.


METHODS
People aged 65 and older without prior venous thrombosis (deep venous thrombosis or pulmonary embolism).


METHODS
Self-reported exercise was measured two or three times during follow-up and was defined as expending more than 500 kcal/wk on exercise, including walking for exercise. Venous thrombosis cases were verified using medical record review.


RESULTS
Of 5,534 participants, 171 developed a first venous thrombosis. Self-reported exercise at baseline was not related to the risk of venous thrombosis after adjustment for sex, age, race, self-reported health, and body mass index (adjusted hazard ratio (HR(adj))=1.16, 95% confidence interval (CI)=0.84-1.61), although with exercise modeled as a time-varying exposure, overall results were in the direction of greater risk of venous thrombosis (HR(adj)=1.38, 95% CI=0.99-1.91). For mild-intensity exercise, such as walking, there was a nonsignificant finding in the direction of benefit (HR(adj)=0.75, 95% CI=0.49-1.16), but strenuous exercise, such as jogging, was associated with greater risk of venous thrombosis (HR(adj)=1.75, 95% CI=1.08-2.83) than no exercise at all.


CONCLUSIONS
In elderly people, strenuous exercise was associated with a higher risk of venous thrombosis than no exercise at all. Future studies are needed to explain this unexpected higher risk.
van Stralen
Karlijn J
KJ
Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
Doggen
Carine J M
CJ
Lumley
Thomas
T
Cushman
Mary
M
Folsom
Aaron R
AR
Psaty
Bruce M
BM
Siscovick
David
D
Rosendaal
Frits R
FR
Heckbert
Susan R
SR
D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015331:Cohort Studies; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D014481:United States; D020246:Venous Thrombosis / Q000453:epidemiology*