High cholesterol in childhood is not a risk factor for premature death
Obesity, glucose intolerance, and hypertension in childhood are significantly associated with increased rates of premature death in adulthood, say researchers. This comes as no surprise since a carbohydrate-based diet, which most children seem to eat these days — as well as our 'healthy' diet — is known to cause all three of the conditions mentioned.
However, the researchers found that childhood hypercholesterolemia (high cholesterol in the blood) was not a major predictor of premature death.
Paul Franks and colleagues of Umeå University Hospital, Sweden, recruited 4857 children of American-Indian heritage (Pima or Tohono O'odham), aged 11.3 years on average who were born between 1945 and 1984 for the study.
On enrollment, the team measured factors such as body mass index (BMI), glucose tolerance, blood pressure, and cholesterol levels. Then the children were followed-up for a median period of 23.9 years.
Over the follow-up period there were 559 premature (before the age of 55 years) deaths, 166 of which were from endogenous causes, defined as "those in which the proximate cause was disease or self-inflicted injury, such as acute alcohol intoxication or drug use."
Writing in the New England Journal of Medicine, Franks and team found that rates of death from endogenous causes in individuals in the highest versus the lowest quartile of childhood BMI were more than double (incidence-rate ratio, 2.30).
In a similar fashion, children in the highest quartile of glucose intolerance and hypertension were 73% and 57% more likely to die prematurely from endogenous causes, respectively, than those in the lowest quartiles.
However, no significant associations between childhood cholesterol levels or systolic or diastolic blood pressure on a continuous scale and premature death were observed.
"Childhood obesity is becoming increasingly prevalent around the globe. Our observations, combined with those of other investigators, suggest that failure to reverse this trend may have wide-reaching consequences for the quality of life and longevity," conclude Franks et al.
In an accompanying editorial, Edward Gregg of the Centers for Disease Control and Prevention, Atlanta, commented: "Since the trends with respect to obesity and diabetes among the Pima Indians have been a reliable harbinger for trends in the rest of the U.S. population during recent decades, the present study should intensify the debate about whether interventions that are initiated during childhood and young adulthood can affect our broader diabetes epidemic."
For me, the most important message to come from this study is that high blood cholesterol was not a risk factor. I think it is important because children are increasingly being targeted for statin treatment to lower 'high' cholesterol. This at a time in their lives when their bodies are growing — and cholesterol is a major building block for cell growth. Under these circumstances, the possible adverse side effects of statins could be disastrous to a growing child.
Now this study shows that the unwise pressure to lower cholesterol in children is not warranted.
Paul W. Franks, et al. Childhood Obesity, Other Cardiovascular Risk Factors, and Premature Death. NEJM 2010; 362:485-493 [FREE ABSTRACT]