(Reuters Health) - Adolescents from low-income families are more likely than their affluent peers to have risk factors for cardiovascular disease like obesity, inactivity, poor nutrition and tobacco use, a U.S. study suggests.

Income inequality has long been linked to disparities in heart disease risk among adults. The new study examined nationally representative data collected from 1999 to 2014 on 11,557 youth, ages 12 to 19, and found that household finances might also impact heart health for teens.

Low-income adolescents may have a greater risk for heart disease at least partly because they learn health habits from their families, and less affluent adults are more likely to smoke or be obese, said study leader Sandra Jackson of the U.S. Centers for Disease Control and Prevention in Atlanta.

But other factors can make it harder for low-income teens to avoid risk factors for heart disease even when their families support a healthy lifestyle at home.

“For example, poverty makes it harder to afford healthy food like fruits and vegetables, or equipment for organized sports,” Jackson said by email. “And, the neighborhoods of less affluent teens may have more fast food restaurants, fewer grocery stores, fewer parks, or less access to other safe places for physical activity.”

During the study period, the overall proportion of teens with obesity rose from 16 percent to 21 percent, representing an increase of nearly 2 million teens becoming obese, researchers report in Pediatrics. But this was driven entirely by increases in the proportion of low-income and middle-income youth with obesity. Obesity among high-income youth remained stable.

By the end of the study period, 22 percent of low-income teens and 26 percent of middle-income youth were obese, compared with less than 15 percent of high-income adolescents.

Similarly, the rate of teen smoking plummeted from 24 percent to 13 percent during the study period. But here, too, income mattered: 21 percent of low-income teens were current smokers at the end of the study compared with just 7 percent of high-income teens.

With diet, too, the overall proportion of adolescents with poor nutrition declined over time, but low-income teens lagged behind wealthier teens. By the end of the study, 65 percent of low-income teens had poor-quality diets, compared with 55 percent of high-income youth.

Exercise, too, was less common among teens from households with lower incomes; 26 percent of low-income teens were physically inactive at the end of the study period compared with 17 percent of high-income adolescents.

The study wasn’t a controlled experiment designed to prove whether or how household income might influence risk factors for heart disease, and it did not look at whether these risk factors directly caused heart problems.

But what happens early in life can shape health in adulthood, said James Gangwisch, a researcher at Columbia University in New York City who wasn’t involved in the study.

“Behavioral patterns such as eating a healthy diet, participating in regular physical activity, and getting adequate sleep that are established in adolescence can endure into adulthood and affect eventual risk for obesity, hypertension, diabetes, heart attack, and stroke,” Gangwisch said by email.

Parents should do their best to teach children how to lead a healthy lifestyle early in life, said Jonathan Mitchell of the University of Pennsylvania’s Perelman School of Medicine and the Children’s Hospital of Philadelphia.

“However, the extent to which this is possible is dependent on income bracket,” Mitchell, who wasn’t involved in the study, said by email. “The challenge is how do we ensure low income communities get access to the resources they need to improve the environment that will help to facilitate healthier behaviors (e.g., better schools, access to higher quality and affordable foods, lower crime etc).”

SOURCE: bit.ly/2Evzhc7 Pediatrics, online October 17, 2018.