(Reuters Health) - Obesity is a strong predictor of high blood pressure early in life, but a U.S study suggests the connection may be stronger for Hispanic and white teens than for adolescents in other racial and ethnic groups.
Researchers examined weight, blood pressure and racial and ethnic data from more than 21,000 youth attending 27 secondary schools in the Houston area. About one-third were overweight or obese, and 2.7 percent had hypertension, or high blood pressure.
Overall, 6.6 percent of obese teens had high blood pressure, as did 2.6 percent of overweight youth and 1.6 percent of normal weight adolescents, the study found. Obesity was much more likely to increase the risk of high blood pressure in Hispanic and white participants.
"While increasing body mass index, a measure of obesity, was associated with increased risk for high blood pressure in all four ethnic groups, the prevalence of high blood pressure was almost six times higher among obese Hispanic adolescents compared to normal weight Hispanics," said senior study author Dr. Joshua Samuels of the McGovern Medical School at the University of Texas Health Science Center in Houston.
"White adolescents also saw dramatic increases in blood pressure with obesity - four times higher - but there were fewer obese white children affected," Samuels said by email.
Participants in the study were 14 years old on average and ranged in age from 10 to 19. Data were collected from 2000 to 2015.
About 23 percent of Hispanic youth were obese, as were 21 percent of black students, 13 percent of white adolescents and 10 percent of Asian participants.
Black students had the highest prevalence of high blood pressure among normal-weight and overweight study participants. But among obese participants, black youth had the lowest rates of hypertension.
At the same time, researchers found a disproportionate increase in the prevalence of high blood pressure for obese Hispanic and white teens.
Compared to normal weight Hispanic youth, their obese peers were 5.8 times more likely to have hypertension and their overweight counterparts were 2.2 times more likely, the study found.
Obese white teens were 4.1 times more likely to have high blood pressure than their normal weight peers, while obese black youth had 2.3 times the risk encountered by their normal weight counterparts.
The study isn't a controlled experiment designed to prove that obesity causes hypertension, and it excluded youth who were taking medication to control their blood pressure. Another limitation of the study is that researchers lacked data on the timing of puberty for study participants, making it impossible to determine how this process might influence weight or blood pressure.
Even so, the results should serve as a reminder to screen obese teens for high blood pressure, regardless of ethnicity, said Dr. Mark DeBoer, a researcher at the University of Virginia School of Medicine in Charlottesville who wasn't involved in the study.
"While hypertension is most common among African American adults and has been seen less often among Hispanic adults, this study serves as notice that obese white and Hispanic children are at least as much at risk for hypertension as African-American children," DeBoer said by email.
"Thinking about hypertension and performing regular screening should lead to earlier identification and treatment - and prevention of downstream consequences," DeBoer added.
SOURCE: bit.ly/2oYY4JQ Pediatrics, online April 10, 2017.