Longer Duration of Obesity Tied to Higher Risk of CHD

You may have a good handle on the clinical degree of obesity in your patients, but have you talked with them about how long they’ve been carrying that weight? A new study suggests if you don’t consider the duration of obesity in addition to body mass index (BMI) and waist circumference, you could be underestimating patients’ health risks.

Study results showed that the longer patients hold onto overall and abdominal fat, the higher their risk of coronary artery calcification (CAC) and progression—a subclinical predictor of coronary heart disease. “We found that with each additional year of obesity, the risk of developing subclinical heart disease increased by about 2% to 4%,” said lead author Jared Reis, PhD, of the National Heart, Lung, and Blood Institute in Bethesda, Md.                 

He and his colleagues looked at the relationship between the duration of overall and abdominal obesity and the presence and 10-year progression of CAC in 3,275 patients from the Coronary Artery Risk Development in Young Adults (CARDIA) study. The participants, ages 18 to 30 at baseline, did not have overall obesity or abdominal obesity when the study began in 1985-86.

The researchers used CT scans to identify CAC at years 15, 20, and 25 of follow-up, and measured the duration of overall and abdominal obesity through BMI and waist circumference at years 2, 5, 7, 10, 15, 20, and 25. During follow-up, 40.4% and 41% developed overall and abdominal obesity, respectively, and CAC occurred in 27.5% of participants. The presence and extent of CAC were significantly associated with the duration of overall and abdominal obesity.

Onset of obesity occurred in the patients’ mid to late 30s, and mean duration was 13.3 years for overall obesity and 12.2 years for abdominal obesity. Longer duration of obesity was also associated with higher levels of blood pressure, glucose, insulin, C-reactive protein, HDL cholesterol, and triglycerides, as well as diabetes and use of antihypertensive and lipid-lowering drugs.      

The authors say that the next step is to develop measures that incorporate both the degree of obesity as well as duration. And with the skyrocketing prevalence of childhood obesity in the U.S., early intervention is also crucial. These findings suggest preventing or delaying the onset of obesity early on could lower the risk of developing CAC in adulthood. “I think our primary solution is to find a way to prevent obesity—continue to encourage identification of effective strategies, seek to prevent the development of obesity during a critical period, which is during young adulthood,” Dr Reis said.

Will these findings change the way you talk about obesity with your patients? Which strategies have you found most effective in obesity prevention and reduction? Let us know in the comments below.

—Colleen Mullarkey

Reference

Reis JP, Loria CM, Lewis CE, et al. Association between duration of overall and abdominal obesity beginning in young adulthood and coronary artery calcification in middle age. JAMA. 2013;310(3):280-288.