A snapshot of cardiovascular health in today’s youth bears no good news for their adult years or the future of the country’s public health, unless there are immediate and sweeping social and cultural changes, according to the American Heart Association.
The AHA’s examination of a sample representing more than 33 million U.S. adolescents showed that less than 1% had an ideal diet score. Less than half of adolescents achieved an ideal score in five or more of the seven cardiovascular health components measured in the study. None had ideal levels in all seven categories.
“The bad news is that an alarming proportion of US children between 12-19 years currently have poor levels of dietary intake and less than optimal levels of physical activity to maintain cardiovascular health,” said study’s lead author Christina M. Shay, Ph.D., University of Oklahoma Health Sciences Center, Oklahoma City. “These unfavorable lifestyle habits have likely already led to the high proportion of children in this study to also exhibit elevated levels of cholesterol, blood glucose, and blood pressure.” (Circulation 2013 April 2 [doi: 10.1161/CIRCULATIONAHA.113.001559]).
The good news, she said, “is that most of these unfavorable cardiovascular disease risk factors are modifiable through implementation of lifestyle change.”
The study follows a 2012 analysis of cardiovascular health in U.S. adults (Circulation 2012;125:45-56).
The AHA recently released the 2020 Strategic Impact Goals to help prevent cardiovascular disease and maintain cardiovascular health from youth throughout adulthood (Circulation 2010;121:586-613). The two analyses provide a baseline to measure progress toward that goal.
AHA defines cardiovascular health by seven health behaviors and factors: no smoking, body mass index, dietary intake, physical activity, blood pressure, blood glucose, and total cholesterol. It quantifies each category with a composite score for CV health with 0 for poor, 1 for intermediate, and 2 for ideal.
The authors examined components of cardiovascular health in 4,673 participants between ages 12 and 19 years from the 2005 to 2010 National Health and Nutrition Examination Surveys (NHANES). The sample group provides an estimated representation of 33.2 million U.S. adolescents.
The sample was well-balanced by sex. The majority of participants were non-Hispanic white (60%), and more than half reported an annual household income of $45,000 or more.
The examination of the data showed that fewer than half of adolescents exhibited five or more of AHA’s ideal cardiovascular health components (45% males and 50% females). Of the maximum score of 14, non-Hispanic white males and females had the highest median Cardiovascular Health Score (9.3 and 9.4 respectively). Mexican American meals and non-Hispanic black females had the lowest score (8.4 and 8.7 respectively).
Females, especially non-Hispanic whites, had a lower prevalence of ideal total cholesterol (65% females v. 72% males), and ideal physical activity (44% v. 67%).
Nearly two-third of the adolescents had an ideal body mass index (66% males and 67% females), but non-Hispanic black females and Mexican American males were more overweight or obese compared with non-Hispanic whites.
Also, nearly two-thirds had ideal smoking status (67% males and 70% females). Ideal smoking status was the most prevalent CV health behavior in all sex and race/ethnicity groups, especially among non-Hispanic blacks.
Ideal blood pressure was the most favorable cardiovascular health factor (78% males and 90% females.)
Meanwhile, females had a higher prevalence of ideal blood glucose (89% v. 74% males). Non-Hispanic blacks had the highest prevalence of ideal fasting blood glucose compared with non-Hispanic whites and Mexican Americans. Roughly a quarter of all adolescents had intermediate fasting blood glucose levels.
“Most children are born in a state of ideal cardiovascular health,” Dr. Shay said in an interview. “However, the poor lifestyles many U.S. children exhibit are leading to a loss of this important asset earlier and earlier in life. A stronger focus on emphasizing improvements in adolescent lifestyles needs to be implemented in the clinical setting.”
She added that “significant environmental and cultural changes need to be implemented with the assistance of parents, educators, health professionals, and legislators to promote healthier lifestyles of adolescents (and people of all ages) in order to improve the cardiovascular health of the US adolescent population.”Dr. Shay said her research team is currently comparing the cardiovascular health of the study’s population from 10 years ago to what it is today. “Considering the direction things have been going from then to now, we are estimating what things are going to look like in the year 2020.”
Her team is also working on estimating costs.