Major Weight Loss Could Return Cardiovascular Risk to Normal Levels in Patients with Obesity

Professor Maia Smith

Research presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD) is underlining the potential impact of weight loss on cardiovascular risk among patients with obesity.

Through an analysis of data from NHANES over more than a decade, results of the investigators' analysis indicate major weight loss among obese patients, which was defined as returning to a healthy weight, could reverse some of the cardiovascular risk associated with obesity, including risk of hypertension and dyslipidemia, to a level similar to those who always maintained a healthy weight.

“The key takeaway of this study is that weight loss is hard, but important, for cardiovascular health”, said lead investigator Professor Maia Smith from St George’s University in Grenada, in a statement. “First of all, it’s no surprise that losing weight and keeping it off is hard. Almost everyone in our original sample who had ever had obesity, stayed that way. But don’t despair: if you do manage to lose weight, it can not only prevent but reverse significant health problems.”

With the obesity epidemic already placing a substantial burden on society and health systems across the US, Smith and colleagues from St. George’s University sought to providence evidence of the effects of achieving and maintaining healthy weight among patients with obesity. To do so, investigators designed their study using data from NHANES from 1999-2013 with data related to BMI. For the purpose of analysis, investigators stratified patients according to obesity status, which was defined as currently obese, always healthy weight, and formerly obese.

Investigators identified a cohort of 20,271 patients for inclusion in their analyses. Of these, 6235 were considered always a healthy weight, 13,710 had obesity, and 326 used to have obesity but had been a healthy weight for at least 1 year. Investigators pointed out adults with obesity were on average older than those who never or currently had obesity and were more likely to smoke cigarettes (36% vs 24% vs 19%, respectively).

The primary outcomes of interest for the study were differences in prevalence of hypertension, dyslipidemia, and diabetes between the groups in crude and adjusted models. Of note, age, gender, smoking status, and ethnicity were used as confounding factors in models.

Upon analysis, results indicated returning to a healthy weight resulted in risks in hypertension (OR, 1.08) and dyslipidemia (OR, 1.13) comparable to those who were never obese (P >.10). 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.

This study, “Cardiovascular risk of former obesity in healthy-weight Americans,” was presented at EASD 2021.