Long-term excess weight is a stronger predictor of cardiovascular risk

Obesity is a known risk factor for cardiovascular disease, but people's weights can shift over time, and little is known about the cumulative impact of excess weight. New research from investigators at Mass General Brigham shows that long-term exposure to excess weight is a stronger predictor of cardiovascular risk than body mass index (BMI) at a single point in time, with the effect strongest in younger people. The results, published in PLOS One, suggest that losing weight and decreasing excess weight exposure may decrease a person's cardiovascular risk.

Excess weight at any given point in time is not a life sentence. What happens to someone's weight over long periods of time matters more for heart health. Our study suggests that if a person lowers their weight, their health outcomes can improve."

Alexander Turchin, MD, MS, of the Division of Endocrinology, Mass General Brigham Department of Medicine

The researchers analyzed data from 136,498 participants in the Nurses' Health Study and Health Professionals Follow-Up Study. All study participants had a baseline BMI above 25 kg/m² and ranged in age from 25 to 69 years for women and 43 to 80 years for men when the study began in 1990. To estimate cumulative exposure to excess BMI over a ten-year period, the researchers averaged the participant's BMI measurements between 1990 and 2000. They began following up on the participants' cardiovascular health in 2000 and continued following them for an average of 16.7 years. During that time, 12,048 (8.8%) of the participants experienced cardiovascular events such as a heart attack or stroke.

The team found a strong relationship between long-term exposure to excess weight and increased cardiovascular disease risk. This effect was strongest for people in the younger age categories and those with the highest cumulative exposure to excess weight. For instance, women who were younger than 35 at baseline had a 60% higher risk of cardiovascular disease with high cumulative exposure to excess weight, compared to 27% for women aged 35-50 and 23% for men 35-65. There was no association for women older than 50 or men older than 65.

"These findings should give patients and their clinicians an impetus to address excess weight to improve their long-term health," said Turchin.