Blood clot risk -- and other problems -- might be tied to how tall you are
Jacqueline Howard, CNN | 9/7/2017, 6 a.m.
The researchers also found that the strong association between blood clot risk and height remained among the siblings.
The strengths of the new study are its large sample sizes and its utilization of siblings, said Dr. Nesochi Okeke-Igbokwe, an attending physician of internal medicine at NYU Langone Health in New York, who was not involved in the new study.
"Overall, it is a solid study with good research methodology used," Okeke-Igbokwe said.
"The bottom line regarding this recent study, whether you are a taller or shorter individual, you must be aware of all the additional lifestyle factors that may increase your risk for blood clots, such as smoking or a sedentary lifestyle," she said. "We have no control over our height, but we certainly can all take the appropriate measures in making healthy lifestyle choices to reduce the risk of various conditions."
One limitation of the study was that the researchers did not have information on the participants' childhoods, home environments and diets. However, they used educational level as a measure of lifestyle factors.
All in all, "this study adds to growing evidence that body size in general is an important factor to consider in determining the risk of VTE. It also gives us information about why VTE occurs in the legs more often than elsewhere, like the arms," said Cushman, who also serves as editor-in-chief of the journal Research and Practice in Thrombosis and Haemostasis.
"Basically, the blood has to travel up a vein against gravity, and when there is a longer distance to travel, there is more opportunity for the blood to clot abnormally," she said. "This is not the case in the arms, for example, where arm movement allows blood to more easily flow out of the limb with the help of gravity."
When it comes to the new study, the "robust" design could be replicated to determine whether height correlates with other health problems, said Ulhas Naik, professor of medicine and director of the Cardeza Center for Vascular Biology Research at the Sidney Kimmel Medical College at Thomas Jefferson University, who was not involved in the new study.
"Being tall, there are benefits in some ways in some diseases, (and) there is the opposite in some other diseases," he said. "This kind of a study is a good starting point to now look at other diseases."
Cancer risk goes up with height?
Epidemiological studies have suggested that taller people are at an increased risk of cancer.
A systematic review paper published in the journal Plos Medicine last year, in which 63 studies on the association of height with cancer risk were analyzed, provided evidence for a potential link between adult height and the risk of colorectal and lung cancers.
The paper also suggested that certain genetic factors and biological pathways affecting adult height may affect the risk of those cancers.
A separate study published in the Journal of the National Cancer Institute in 2015 provided strong evidence that adult height can be a risk factor for breast cancer in women.