Significant weight loss may reverse some of the cardiovascular (CV) risk associated with obesity, according to study findings being presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD), held online September 28 – October 1, 2021.
The cross-sectional analysis, led by Professor Maia Smith from St George’s University in Grenada, used US National Health and Nutrition Examination Survey (NHANES) data from 1999-2013 to profile formerly obese American adults and to compare CV risk factors identified in that group to those of currently obese individuals and to those of adults who have always been at a healthy weight.
More than 40% of adult Americans have obesity (BMI >30kg/m²) and close to 1 in 10 is classed as having severe obesity (BMI ≥40 kg/m2), according to a press statement. While the direct association of excess body weight with CV risk factors is well recognized, there is little research investigating whether the effects of obesity persist in those who subsequently achieve and maintain a healthy weight, the authors write in the study abstract. They investigated further.
Specifically, researchers compared the prevalence of hypertension, dyslipidemia, and diabetes, first using crude data and then controlling for participant age, gender, smoking status, and ethnicity.
The NHANES cohort from 1999-2013 numbered 20 271 from which Smith and colleagues defined 3 groups: currently obese (n=13 710); always at a healthy weight (n=6235); and previously had obesity but had maintained a healthy weight for at least on year (n=326).
Investigators found that adults who had previously had obesity and returned to a healthy weight were on average older than those who never, or currently had obesity and also were more likely to smoke cigarettes (36%, vs 24 and 19%.)
After controlling for age, gender, smoking status, and ethnicity among those who had returned to a normal healthy weight the group’s risk of hypertension (odds ratio [OR], 1.08) and dyslipidemia (OR, 1.13) were comparable to those who had never been obese (p<.10 for both).
“Major weight loss appeared to reverse most of the cardiovascular risks associated with obesity, even in those who continued to smoke and especially in those who quit. Risk of diabetes, but not hypertension or dyslipidemia, remained elevated over those who were never obese: however, even diabetes risk dropped with weight loss."
However, investigators pointed out the odds of diabetes was still 3-fold greater among those with a history of obesity (OR, 2.93) and more than 7-fold greater among those who currently had obesity (OR, 7.53) compared to those who were never obese (P<.01). Additionally, those who were currently obese had 3-fold greater odds of hypertension (OR, 3.14) and dyslipidemia (OR, 3.11) compared to those who were currently obese.
“Major weight loss appeared to reverse most of the cardiovascular risks associated with obesity, even in those who continued to smoke and especially in those who quit. Risk of diabetes, but not hypertension or dyslipidemia, remained elevated over those who were never obese: however, even diabetes risk dropped with weight loss,” wrote investigators in their conclusion.
Source: Smith MP, Mansour W, de Gale B. Cardiovascular risk of former obesity in healthy-weight Americans. Abstract presented at: Annual Meeting of the European Association for the Study of Diabetes; held online September 28-October 1, 2021.