Years of Heaviness Matter to Your Heart

Key Takeaways

• The number of years spent obese or overweight contributes to higher likelihood of heart damage
• For each 10 years that a person spent obese, their risk increased 1.25 times
• Losing weight even after decades of obesity or being overweight may help reduce risk
• The heart has the ability to heal somewhat

Researchers from Johns Hopkins have shown that the number of years spent overweight or obese appear to "add up" to a distinct risk factor for heart damage.

People with a longer history of heaviness are more likely to test positive for a chemical marker of so-called "silent" heart damage than those with a shorter history.

Silent heart damage was detected with blood tests showing elevated troponin levels of 14 nanograms or more per litre.  

"We're finding that people's weight from age 25 onwards is linked to the risk of more or less heart damage, as measured by levels of the protein troponin, later in life" says Chiadi Ndumele, M.D., M.H.S., a Professor of Medicine at Johns Hopkins University.

"What our findings suggest is that even in the absence of such heart disease risk factors as high blood pressure, diabetes or kidney disease, the number of years spent obese or overweight contributes to the higher likelihood of heart damage."

The Study

The research team used data gathered on 9,062 participants in the Atherosclerosis Risk in Communities (ARIC) study.

Participants were were seen four times over a 10-11 year period, to assess body mass index (BMI), history of heart disease and levels of high sensitivity troponin in the blood.

Participants also self-reported their weight at age 25, which provided information on weight from young adulthood through late middle age and elderly years.

Outcomes

• Those who increased in BMI to overweight and obese ranges at the fourth visit were 1.5 times more likely to have troponin levels indicating heart damage.
• Those people who were obese at both the first and fourth visits were twice as likely as those with persistently normal weight to have increased troponin levels.
• Those with obesity at both the fourth visit and at age 25 were almost four times more likely to have increased troponin levels.

On a scale of zero to 50 years, the researchers then tabulated the number of years each person spent being obese, defined as a BMI over 30.

For each 10 years that a person spent obese, their risk of having elevated troponin increased 1.25 times, even when accounting for heart disease risk due to high blood pressure, diabetes and kidney disease.

Ndumele says there is some evidence that losing weight even after decades of obesity or being overweight may help reduce troponin levels and that the heart has the ability to heal somewhat, but the extent to which it can heal and the number of years spent obese that may cause permanent damage are unknown and require more study.

Calculate Your BMI

BMI can be calculated (easy with the calculator here) by dividing your weight in kilograms by your height in metres squared.

Body mass index (BMI) = weight(kg) ÷ height(m)²

BMI <18.5	Underweight
BMI 18.5-25	Healthy Weight
BMI 25-30	Overweight
BMI >30	Obese

References

Weight History and Subclinical Myocardial Damage (Abstract. Charge for full access)

Johns Hopkins Press Release