Watch out, brothers and sisters—if a sibling has
experienced blood clots, you may have a 50-fold
increase in risk for the condition.
Researchers in Sweden are the first to link
venous thromboembolism (VTE) and the risk in other
family members in a nationwide setting, sorted by
age and gender. They used a nationwide
hospitalization registry to explore the influence of
sibling history on these dangerous blood clots. This
is a quick look at VTE, the sibling connection and
some preventive tips for people of all ages.
What is VTE?
VTE consists of deep vein thrombosis (DVT), which
occurs when blood clots form in the deep veins of
legs or pelvis. VTE also encompasses pulmonary
embolism, which is when the blood clot breaks away
from the original location, travels to the lungs and
blocks pulmonary arteries, becoming deadly.
It is the third most common cardiovascular
illness, after stroke and heart attack, and affects
one in 1,000 people every year. One-third of VTE
cases also involve a pulmonary embolism.
There are three main factors necessary to
maintain the correct thickness and flow of blood in
the vessels. When one of these is disrupted, a blood
clot is likely to occur.
The flow of blood – When blood flow within the
veins is slowed or blocked, this allows more time
for the blood to clot.
The vessel wall – The blood vessel wall lining
must be intact. Damage to the wall (for example,
from surgery or injury) hinders the flow of blood
and may lead to the formation of a blood clot.
Blood composition – The body maintains an effective
balance between processes that dissolve and form
blood clots. If this balance is disturbed and there
are too many blood-clotting factors present, this
increases the tendency of the blood to clot.
The Sibling Connection
Depending on the number of children in a given
family with the disorder, the risk is that much
greater for other siblings. If one sibling has VTE,
the risk is two times greater, but 50 times greater
when two or more brothers or sisters have the same.
These hereditary factors are helpful in
determining the risk of VTE in men and women between
the ages of 10 and 69. Those families with a history
of VTE have a strong genetic link to occurrences of
the disorder in siblings.
In a person between the ages of 10 and 19, if a
sibling does have VTE issues, the risk of developing
it is nearly five times greater than in those
without a sibling history of the disorder. In
the older population of ages 60 to 69, the risk is
twice as much than when younger.
Women have a higher occurrence of VTE, especially
between the ages of 10 to 40, when a sibling already
has been diagnosed. The rate becomes higher for men
over the age of 50.
The Swedish researchers found that most of the
familial risk of increased VTE occurrence was from
genetics, not environmental factors. This
information is useful to medical professionals,
especially when performing a procedure on someone
who may have a higher risk of clotting due to a
There are a number of ways to help prevent VTE
from occurring or limit the severity of the
- Early mobilization after surgery
- Sit with legs together rather than crossed
- Keep mobile
- Weight management
- Quit smoking
- Avoid tight clothing
- Use of graduated compression stockings
- Use of venous foot pumps, and
- Use of blood-thinning drugs (usually
When faced with a chance of having VTE, the first
thing is to confirm the diagnosis, then decide on
treatment, as well as self-management. The Swedish
may have found a familial connection, but there are
healthy lifestyle tips anyone can implement to make
the threat of blood clots less likely to occur in
the first place.
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