Patients’ BMI history predicts their future CVD risk

Questioning older patients about their weight earlier in life could be a low-tech, low-cost way to better predict a person’s future risk of heart disease, according to a study published in the Journal of the American Heart Association.

The U.S. estimates 36 percent of its population is obese, and we know those individuals see higher rates of heart disease and diabetes, Michael Fliotsos, BS, and colleagues at Johns Hopkins School of Medicine wrote in the journal. But scientists aren’t sure of how, or even if, the timeframe during which a person gains weight impacts the future trajectory of their heart health.

“Prior studies have suggested that weight patterns are often set well before midlife,” Fliotsos and co-authors wrote. “Weight gain in early or middle adulthood may be riskier than weight gain in later adulthood.”

The researchers considered 6,437 patients enrolled in the MESA (Multi-Ethnic Study of Atherosclerosis) cohort between 2000 and 2002 for their study, which evaluated the utility of retrospectively asking patients about their weights earlier in adulthood. The participants hailed from six major U.S. cities, including Baltimore, Chicago, Los Angeles and New York City, and on average they were 62 years old at baseline.

All patients filled out a survey in which they self-reported their weights at ages 20 and 40, the authors said. Their weights were further monitored over the study period in five in-person visits, and those numbers were then translated into BMI figures. Fliotsos et al. considered a BMI of less than 25 to be normal, while a BMI between 25 and 30 indicated a patient was overweight and a BMI over 30 meant a patient was obese.

By the end of 13-year follow-up, interviews and medical records identified 290 cases of heart failure and 828 CVD events like heart attacks, stroke or death in the study population. The authors said the standard measured weights taken at clinic visits were associated with later heart failure risk, with a 34 percent increased risk of HF for each 5 kilograms-per-square-meter increase in BMI after accounting for other established CVD risk factors.

That finding was expected, but Fliotsos and colleagues reported that even after taking into account the more frequent measured weights at older ages, a self-reported history of obesity at ages 20 and 40 were associated with a threefold risk and a twofold risk of incident heart failure, respectively.

“Asking patients about their weights at ages 20 and 40 is a low-tech tool that can easily be utilized at any clinical encounter and might provide additional insight into risk beyond considering a single baseline weight measure alone,” the authors wrote. “Our results might support the potential utility of asking patients about their prior weights throughout their adult lives to more completely evaluate their HF and ASCVD risk, incremental to their current weight and risk profile.”

The team said the fact that patients self-reported their weight history is a limitation of the study, since it exposes the data to a high potential for bias. But they also said they believe most older adults can recall their younger weights with reasonable accuracy, and the question is such a simple, quick one that it can only help physicians better advise their patients.

“While a single baseline measure of BMI in middle-aged to older adulthood does predict incident HF (and to a lesser extent ASCVD) risk, it may not tell the whole story,” Fliotsos and co-authors wrote. “A self-reported weight history from age 20 and age 40 years was still independently associated with future HF risk. Our study supports the potential utility of assessing an individual’s weight throughout decades of adulthood to gain a more comprehensive understanding of one’s risk for developing incident HF.”