Image by Kevin MacKenzie
Thrombus
Taller individuals have an increased risk of venous thromboembolism (VTE), according to research published in Circulation: Cardiovascular Genetics.
In a study of more than 2 million Swedish siblings, researchers found that height was an independent predictor of VTE, with the lowest VTE risk observed in the shortest participants.
The association between height and VTE was present in both men and women (all of whom had been pregnant).
“Height is not something we can do anything about,” noted study author Bengt Zöller, MD, PhD, of Lund University and Malmö University Hospital in Sweden.
“However, the height in the population has increased and continues increasing, which could be contributing to the fact that the incidence of thrombosis has increased.”
For this study, Dr Zöller and his colleagues analyzed 2 cohorts of Swedish individuals without a prior VTE.
There were 1,610,870 men who were followed from enrollment—1969 to 2010—until 2012.
And there were 1,093,342 women who were followed from their first pregnancy—1982 to 2012—until 2012.
The researchers identified sibling pairs so they could adjust their analysis for genetic and environmental factors that might impact VTE risk.
The team found the risk of VTE was 69% lower for the shortest women (<155 cm, <5′1″) than it was for the tallest women (≥185 cm, ≥6′).
The risk of VTE was 65% lower for the shortest men (<160 cm, <5′3″) than the tallest men (≥190 cm, ≥6′2″).
Dr Zöller said gravity may influence the association between height and VTE risk.
“It could just be that because taller individuals have longer leg veins, there is more surface area where problems can occur,” he said. “There is also more gravitational pressure in leg veins of taller persons that can increase the risk of blood flow slowing or temporarily stopping.”
It is worth noting that the researchers didn’t have access to data for childhood and parent lifestyle factors that might influence VTE risk, such as smoking, diet, and physical activity. In addition, the study consisted of Swedish people and may not be translatable to other populations.
Nevertheless, Dr Zöller said, “I think we should start to include height in [VTE] risk assessment, just as [we do] overweight, although formal studies are needed to determine exactly how height interacts with inherited blood disorders and other conditions.”
