OBESITY AS INDEPENDENT CORONARY RISK FACTOR

We have always knew that obesity is an important coronary risk factor. However, what we are not sure about is whether obesity per se is the issue or whether obesity operates through other risk factors like hypertension or diabetes.
Well a recent paper published by Dr Jared Reis from the National Heart, Lung and Blood institute attempts to look into this issue. The paper is published in the July 17th issue of the Journal of the American Medical Association. The paper is entitled, "Association between duration of overall and abdominal obesity beginning in young adulthood and coronary artery calcification in middle age. "
Dr Jared and colleagues reviewed data from the CARDIA cohort. The CARDIA ( Coronary Artery Risk Development in Young Adults ) cohort. The CARDIA cohort began enrolment in 1985-86, the period when obesity became prominent.
They reviewed the data on 3,275 Americans of 18-30yrs age group. These subjects were not obese at enrolment. Followed them up at yr 2,5,7,10,15,20 and 25 yrs, measuring their weight and also abdominal girth. At year 15, 20 and 25, their Calcium Artery Calicification ( CAC ) Score was also measured. They were using the CAC as a measure of the presence of atherosclerosis.
They found that on followup, 40% of the subjects became obese. 25% of these obesed individuals had an increase CAC score,compared to 20% in those who were not obese on follow up.
The findings seemed to suggest that obesity is an independent predictor of increasing CAC. The longer the obesity, the greater the increase in CAC.
What the paper did not say is whether a weight reduction, brought about a lowering of the CAC.
This paper is simple in many ways, but does give some information that weight gain over ten twenty years seem to bring about early changes of atherosclerosis, without any other co-risk factors.