November 17, 2011
ST LOUIS (MD Consult) - Among children who are overweight or obese, cardiovascular risk factors are not increased for those are nonobese in adulthood, according to a study in the November 17, 2011, issue of The New England Journal of Medicine.
The researchers analyzed data from 4 prospective studies of cardiovascular risk factors involving children with follow-up into adulthood. The analysis included a total of 6,328 participants, with a mean follow-up of 23 years. All underwent assessment of body mass index (BMI) in childhood and adulthood.
Cardiovascular risk factors at follow-up were compared for participants who were normal-weight in both childhood and adulthood (4,742 participants), overweight or obese in childhood but nonobese in adulthood (274 participants), overweight or obese in childhood and obese in adulthood (500 participants), and normal-weight in childhood but obese in adulthood (812 participants). The lead author was Dr Markus Juonala of University of Turku and Turku University Hospital, Finland.
Cardiovascular risk factors were significantly increased for participants who had high adiposity in both childhood and adulthood, compared to those who had normal BMI in childhood and were nonobese in adulthood. Relative risks were 5.4 for type 2 diabetes, 2.7 for hypertension. 1.8 for elevated low-density lipoprotein cholesterol, 2.1 for reduced high-density lipoprotein cholesterol, 3.0 for elevated triglycerides, and 1.7 for increased carotid artery intima-media thickness.
In contrast, none of these risks was increased for participants who had high BMI in childhood but were nonobese in adulthood. For obese adults who had been normal-weight in childhood, risks were similar to those who had been overweight or obese in childhood.
Childhood obesity has been linked to an increased risk of cardiovascular disease and death. It is unclear whether childhood obesity increases risks independently of the effects of obesity in adulthood.
The new study confirms the increased rates of cardiovascular risk factors among overweight or obese children who become obese adults. However, for children who have high BMI but are not obese as adults, risks are similar to those with normal BMI at both times. Although no clinical recommendations can be made from the observational study, the researchers write, "[W]e hypothesize that reducing BMI in children and adolescents who are overweight or obese could reduce their cardiovascular risk."