Teens who are overweight, but metabolically healthy, still run a significantly higher risk of developing increased carotid intimal-medial thickness and other cardiovascular risk factors as adults.
A study of more than 1,600 Finns who were followed for up to 25 years found that, while childhood metabolic risk factors significantly contributed to adult cardiovascular risks, obesity in isolation was also a very strong predictor, Dr. Juha Koskinen and his colleagues reported online April 17 in Diabetes Care (Diab. Care 2014 April 14 [doi: 10.2337/dc14-0008]).
"The findings demonstrate an increased risk of future raised intimal-medial thickness in pediatric overweight individuals, even in those without metabolic derangement in youth – a finding that assists with clinical decision making in screening and pediatric overweight and obesity management," wrote Dr. Koskinen of the University of Turku, Finland, and his coauthors.
The ongoing Cardiovascular Risk in Young Finns Study is one of the largest follow-up studies tracking cardiovascular risk from childhood to adulthood. Its main aim is to determine how childhood lifestyle, as well as biological and psychological measures, affects the risk of future cardiovascular diseases. Initiated in 1980, it has since tracked a dwindling number of the 3,596 young people originally enrolled when they were 3-18 years old. In 2007, a total of 2,204 subjects were examined. The most recent follow-up was performed in 2011 and included blood samples and questionnaires but not ultrasound data.
For this study, the researchers focused on 1,617 youths who were a mean of 16 years old in 1986. The researchers divided this cohort into four groups according to baseline cardiovascular risk factors:
• Group 1: normal weight, no metabolic problems.
• Group 2: normal weight, at least one metabolic problem, such as elevated blood pressure, glucose, triglycerides, low HDL cholesterol, and high LDL cholesterol.
• Group 3: overweight/obese, no metabolic problems.
• Group 4: overweight/obese, at least one metabolic problem.
They assessed the 21-year risk of subclinical atherosclerosis (as determined by ultrasonographic measurement of carotid intimal-medial thickness), and the 21- to 25-year risks of developing type 2 diabetes and metabolic syndrome.
By the 21-year follow-up, carotid intimal-medial thickness had increased linearly according to the baseline groupings, with overweight/obese subjects (groups 3 and 4) having significantly greater values than group 1. After adjusting for baseline glucose, triglycerides, lipids, systolic blood pressure, smoking, and family history of heart disease, the difference between groups 1 and 2 was not significant, but the differences between all of the other groups remained so.
By 25 years, compared with subjects with normal weight and metabolic status, those who were overweight but metabolically normal at baseline were twice as likely to have metabolic syndrome and six times as likely to have diabetes.
Subjects who were overweight and had metabolic problems at baseline were more than three times as likely to have metabolic syndrome and three times as likely to have diabetes.
"Our analysis ... supports the encouragement of young individuals to avoid being overweight/ obese, irrespective of their metabolic profile," the authors concluded.
The Cardiovascular Risk in Young Finns Study is supported by several national and private grants. None of the authors reported any financial disclosures.