Each year, more than 100,000 Americans die from venous thromboembolisms (VTE), a disease where a blood clot forms — usually in the vein of a leg — and can travel to the lungs, where it may cause death. New studies have suggested that people of taller height are at greater risk for the condition. The University of Minnesota School of Public Health recently completed the first study examining the link between height and VTE from a genetic perspective, and confirmed that taller height is indeed related to increased risk of VTEs.
[Photo: Mr. Nick Roetker]
The study was published in the Journal of Thrombosis and Haemostasis.
“It’s interesting because studies have shown that shorter people are at greater risk for coronary heart disease and most other arterial thrombotic diseases,” said lead author and PhD student Mr. Nick Roetker. “In the case of venous thromboembolism, it’s the opposite.”
The paper used genetic and health data from participants in three related studies — including the Atherosclerosis Risk in Communities (ARIC) study, which has a center at the University of Minnesota. The study was co-written by professors Dr. Aaron Folsom and Dr. Jim Pankow, as well as associate professors Dr. Pamela Lutsey, Dr. Weihong Tang, and Dr. Richard MacLehose.
“We found that for every 10-centimeter increment in height, there’s a 30-40 percent relative increase risk of VTE,” said Mr. Roetker. “So, we would expect a person who is 182 cm to have 1.3-1.4 times greater risk of VTE compared to someone who is 172 cm, assuming they share the same values for other risk factors.”
The association between height and VTE occurrence was confirmed using a relatively new study technique known as Mendelian randomization. For the method, the researchers looked to see if genetic (DNA) variations associated with taller height were also associated with greater risk of VTE. In theory, since genetic variations are randomly inherited, the technique allows for better estimation of the true association between height and VTE risk compared to traditional observational studies, where the appearance of a relationship might be created by confounding factors.
“We still don’t know why taller people have greater risk for VTE, but it may be because their veins have a larger surface area or number of venous valves in which clots can form,” said Mr. Roetker. “The Mendelian randomization findings suggest there may be value in investigating the link between height and VTE, which could help us to better understand the pathophysiology of the disease.”
Mr. Roetker said that he and his advisers are excited about their success using Mendelian randomization and are gearing up to employ the method in additional disease-related studies.Tags: Epidemiology, Health Promotion and Communication, Minnesota