HealthDay News — Teenagers today have more risk factors for cardiovascular disease than those in decades past, largely due to increases in diabetes and prediabetes associated with overweight and obesity, results of a nationally representative survey indicate.
Although the proportion of overweight and obese teens remained stable at 34% during the past decade, the proportion of teens with diabetes or prediabetes more than doubled from 9% to 21% (P<0.05), data from nearly 4,000 teenagers included in the National Health and Nutrition Examination Survey (NHANES) indicate.
Furthermore, 49% of the overweight teens and 61% of the obese teens had one or more CVD risk factors, study researcher Ashleigh L. May, PhD, of the CDC, and colleagues reported in Pediatrics.
These findings suggest that U.S. teens “carry a substantial burden of CVD risk factors”, according to the researchers, particularly those who are overweight or obese. “Adolescence represents a window of opportunity for assessment of CVD risk factors and the promotion of lifestyles that will affect the development and progression of CVD,” they added.
May and colleagues analyzed the prevalence of four major CVD risk factors — high levels of low-density lipoprotein cholesterol (LDL), low levels of high-density lipoprotein (HDL) cholesterol, hypertension and diabetes — in 3,383 adolescents ages 12 to 19 from 1998 to 2008.
Overall prevalence for each of the four risk factors was more than 10% in the study population. The prevalence of prediabetes/diabetes increased from 9% in 1999 to 23% in 2008, and the proportion of teens with low HDL cholesterol(<35 mg/dL), thought to be protective against CVD, fell drastically from 9% to 3% (P<0.05).
However, rates of prehypertension/hypertension (17% in 1999-2000 vs. 13% in 2007-2008) and borderline-high/high LDL cholesterol (23% and 19%, respectively) did not change significantly.
May and colleagues suggested that these CVD risk factors may have plateaued, since the overall proportion of obese teens did not increase during the study period.
Overall, 43% of adolescents had at least one risk factor for CVD, but distribution varied significantly by factors including gender, age and BMI. Among overweight and obese adolescents the most common combination of CVD risk factors was prehypertension/hypertension and borderline-high/high LDL cholesterol (26%), the researchers found.
Boys were more likely than girls to have any number of the CVD risk factors, and older adolescents aged 18 to 19 years were more likely to have two or more risk factors than those aged 12 to 13 years. No significant differences were identified based on race or ethnicity.
“[T]he results presented here indicate that from a population level, a large proportion of adolescents, regardless of weight status, would benefit from interventions such as Let’s Move and programs that promote overall healthy lifestyles, including physical activity, healthy diet and healthy weight maintenance,” the researchers wrote.
Study limitations included few data on other CVD risk factors, a lack of other nationally representative surveys in similar age groups for which to compare data and reliance on BMI as a measure of obesity, the researchers noted.