By Rachael Rettner, Senior Writer
Published: 04/15/2014 08:37 AM EDT on LiveScience
Teens who take longer to reach their full height may be at increased risk for certain types of brain tumors later in life, a new study suggests.
The study involved nearly 2,600 people, including 1,045 people with glioma, a category of brain and spinal tumors that arise from cells known as glial cells; 274 people with meningioma, a type of tumor that forms in the lining of the brain; and 1,242 people without brain tumors. Participants, who were mostly in their 50s, reported how old they were when they stopped growing.
On average, men reached their full height at age 17, while women reached their full height at age 16.
For each additional year it took people to reach their full height, the risk of glioma increased by 14 percent for men and 11 percent for women, the study found.
People who stopped growing at age 19 or older had nearly twice the risk of glioma as those who stopped growing at age 15 or younger. [10 Things You Didn't Know About the Brain]
The reason for the possible link is not clear. It's possible that teens who take longer to stop growing are exposed to growth hormonesfor longer periods, which may affect glioma risk, said study researcher Rebecca Little, a and doctoral student at the University of Alabama at Birmingham.
Previous studies have linked having a higher body mass index (BMI) in young adulthood, and taller stature overall, with glioma risk, but the new findings are a first, the researchers said.
No link was found between the age at which people stopped growing and their risk of meningioma, the researchers noted.
Because the study was conducted in a single region of the United States — the Southeast — additional research is needed to replicate the findings in other groups of people, Little said.
The study found only an association, and cannot prove that taking longer to stop growing causes brain tumors.
Interestingly, the risk of glioma was highest among people who took longer to reach their full height, but whose final height was on the short side. This finding could be due to chance, so more research is needed to confirm it, Little said. But it's possible that these people's bodies produce a lower level of growth hormones over a prolonged period, which may confer a higher risk of tumors than a higher level of growth hormones over a short period, Little said.
It's possible that some people may not accurately recall the age at which they stopped growing, but Little noted that people are often good at remembering their height and weight at certain time points in life.
The study was presented this week at the meeting of the American Association for Cancer Research in San Diego.