Tackling Obesity for Heart Health: A Global Weight Crisis

Obesity adds stress to the body by forcing the need for more oxygen and nutrients, which can lead to hypertension, heart failure, arrhythmias, type 2 diabetes (T2D), cardiovascular disease (CVD), and sleep disorders—among its many comorbidities—and is a major risk factor for cardiometabolic disorders.^1-5

On day 3 of the 2024 European Society of Cardiology (ESC) Congress, the ongoing and damaging obesity epidemic was tackled head on, with high emotions. The following exclamations were made:

• “Why are we in this mess?”
• “It’s a freakin’ disaster!”
• “What are we doing for the next generation?”
• “We really need to know our enemy.”

The session, “Fixing the Obesity Crisis,” from the American College of Cardiology and the American Heart Association took a multipronged approach to addressing this epidemic, by focusing on 3 key areas of interest: the crisis’ origins, why we must treat this condition now, and its economic implications.

“Obesity is an obvious topic that affects many, many people in the world, and we now realize how important it gets to address this both pharmacologically, but of course, also in terms of lifestyle changes and behavioral changes,” said Franz Weidinger, MD, current president of the ESC and head of cardiology at Klinik Landstrasse at Vienna Medical University in Austria, who cochaired the session. “It is one of the biggest remaining issues and risk factors that we must tackle if we want to make a real impact on improving cardiovascular health and further reducing cardiovascular mortality.”

Naveed Sattar, PhD | Image Credit: University of Glasgow

The Origins of the Obesity Epidemic⁶

Naveed Sattar, PhD, emphasized that obesity actually is a pandemic, with inextricable links to CVD and multimorbidity. A professor of cardiometabolic medicine at the University of Glasgow, and coleader of a CVD prevention clinic at Glasgow Royal Infirmary, he explained how major changes in society have conspired to make obesity such a serious global issue. These include a drop in physical activity brought on by the dominant influence of motorized transportation and sedentary employment, major changes in food production, our dependence on mobile technology—the pace is exceeding human evolution, excessive caloric intake, and a lack of time—to name a few.

“The situation is not getting any better,” he exclaimed. “It’s getting worse, accelerating all over the world,” and Sattar said greed on the part of the food industry is a major factor in this growth, leading to a lack of healthy food options and large portion sizes.

“If you provide more fast foods, people eat them,” he said, “because we can’t resist our biology.” The problem with this is that satiety signals are impaired in people who have obesity, which is driven by misfired adiposity signals from adiponectin, insulin, and leptin and gut hormones that include peptide YY, ghrelin (also known as the hunger hormone), and cholecystokinin.

This excess adiposity has to be treated, otherwise we are promoting multimorbidity, he exclaimed. “Now, more people are living with cardiovascular disease, more people are living with obesity and cardiovascular disease, and more people are living with multimorbidity linked to obesity and its various aspects.”

Hadley Wilson, MD, MACC | Image Credit: Carolinas Medical Center

We Can Reduce CV Risk by Treating Obesity⁷

“The search for an obesity cure has been an 80-year quest,” said B. Hadley Wilson, MD, MACC, president, Medical Staff, Carolinas Medical Center, and immediate past president of the American College of Cardiology. “But things are a lot worse now.”

There are currently 5600 million adults living with obesity—which affect more women (14%) than men (10%)—and 43 million children living with obesity, and by 2030, more than 1 billion adults are predicted to have obesity.^8-10 In the US alone, in 2020, 42.4% of US adults were living with obesity (> BMI 30 kg/m²) and 9.2%, severe obesity (> BMI 40kg/m²); by 2030, 30% of the US adult population could be living with obesity.¹¹

A good place to start is defining obesity. And although body mass index (BMI) remains a controversial measure of physical fitness, the experts on this panel stand by its utility as a screening tool for obesity—with the caveat that diagnosing obesity “should always be a clinical diagnosis, based on excess dysfunctional body fat that impairs health.” Further, BMI shows utility for pharmacotherapy indications and surgery indications, Wilson added, and on a population basis, it correlates with body fat, comorbidities, and mortality.

Obesity care needs to be multimodal, Wilson said, striving to target lifestyle modification for everyone but reserving increasingly invasive methods for higher-risk groups with increased BMIs that can produce greater weight losses; for example, anti-obesity medications in those with a BMI of at least 30 kg/m², endobariatric surgery (eg, gastric sleeve, intragastric balloon , vagal nerve blocking therapy) in those with a BMI between 30 and 40 kg/m², and bariatric surgery in those with morbid obesity (BMI of at least 35 kg/m²).

Attempting to improve CV outcomes alone will not work.

Other promising methods are the newer pharmacological treatments, the incretins and glucagon, which have 3 potential targets: glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic (GIP), and glucagon receptors. And semaglutide.¹²

He closed by highlighting how patients with obesity can better their CV risk and overall health through weight loss:

• 0% to 5%: hypertension and hyperglycemia rates go down
• 5% to 10%: prevention of T2D, polycystic ovarian syndrome, dyslipidemia, asthma, and nonalcoholic fatty liver disease
• 10% to 15%: improvements in CVD, urinary stress incontinence, nonalcoholic steatohepatitis, gastroesophageal reflux disease, and knee osteoarthritis
• More than 15%: remission of T2D, reduction in CV mortality, and clinical symptom improvement in heart failure with preserved ejection fraction

Dhruv S. Kazi, MD, MSc, MS | Image Credit: Harvard Medical School

The Economics of Obesity¹³

Can we afford to treat obesity? Can we afford not to? So asked Dhruv S. Kazi, MD, MSc, MS, associate director, Smith Center for Outcomes Research; director, Cardiac Critical Care, Beth Israel Deaconess Medical Center; and associate professor of medicine, Harvard Medical School. The problem is multidimensional, and so we need a multimodal approach, he explained.

“Obesity is common, it is catastrophic, it is costly, it is everywhere,” he also noted. “Fortunately, we can do something about it as clinicians.” There is potential to transform outcomes, but only if affordability and adherence can be scaled up to meet the scope of the current obesity problem—including for the newer medications (ie, GLP-1s), for surgery (currently unaffordable for many), and via policy interventions that focus on obesity prevention and the food environment.

Direct costs (medical and nonmedical) comprise two-thirds of these costs, and indirect costs (from premature mortality and productivity losses), the rest. Middle-income countries will bear the brunt of this burden, he continued. Between 2020 and 2060, the cost of treating obesity and overweight are projected to increase almost 10-fold globally, from $2 trillion to $18 trillion,¹⁴ and by 2050 in the US, these costs are expected to account for 5% to 14% of health expenditures, with principal reason behind this that the costs of these drugs in the US far outpace the rest of the world. At present, there is also questionable economic value for semaglutide, with high rates of discontinuation that are seen starting at 6 months after treatment initiation.

Efficiency (or cost-effectiveness and ROI), affordability, and equity are the 3 key dimensions of societal value that must be considered if we are to determine absolute, or legacy, benefit. Also important are qualitative and quantitative analyses to figure out how to increase adherence.

References

1. Metabolic and bariatric surgery blog: three ways obesity contributes to heart disease. Penn Medicine. April 12, 2022. Accessed September 1, 2024. https://www.pennmedicine.org/updates/blogs/metabolic-and-bariatric-surgery-blog/2019/march/obesity-and-heart-disease#:~:text=Obese%20individuals%20require%20more%20blood,more%20common%20for%20obese%20individuals

2. Weight: a silent heart risk. Johns Hopkins Medicine. Accessed September 1, 2024. https://www.hopkinsmedicine.org/health/wellness-and-prevention/weight-a-silent-heart-risk

3. Ashraf MJ, Baweja P. Obesity: the ‘huge’ problem in cardiovascular diseases. Mo Med. 2013;110(6): 499-504.

4. Powell-Wiley TM, Poirier P, Burke LE, et al; American Heart Association Council on Lifestyle and Cardiometabolic Health; Council on Cardiovascular and Stroke Nursing; Council on Clinical Cardiology; Council on Epidemiology and Prevention; and Stroke Council. Obesity and cardiovascular disease: a scientific statement from the American Heart Association. Circulation. 2021;143(21):e984-e1010. doi:10.1161/CIR.0000000000000973

5. Valenzuela PL, Carrera-Bastos P, Castillo-García A, Lieberman DE, Santos-Lozano A, Lucia A. Obesity and the risk of cardiometabolic diseases. Nat Rev Cardiol. 2023;20(7):475-494. doi:10.1038/s41569-023-00847-5

6. Sattar N. The origins of the obesity epidemic. Presented at: ESC Congress; August 30-September 2, 2024; London, England.

7. Wilson H. We can reduce cardiovascular risk by treating obesity. Presented at: ESC Congress; August 30-September 2, 2024; London, England.

8. Finucane MM, Stevens GA, Cowan MJ, et al. National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9·1 million participants. Lancet. 2011;377(9765):557-567. doi:10.1016/S0140-6736(10)62037-5

9. Kelly T, Yang W, Chen CS, Reynolds K, He J. Global burden of obesity in 2005 and projections to 2030. Int J Obese (Lond). 2008;32(9):1431-1437. doi:10.1038/ijo.2008.102

10. de Onis M, Blössner M, Borghi E. Global prevalence and trends of overweight and obesity among preschool children. Am J Clin Nutr. 2010;92(5):1257-1264. doi:10.3945/ajcn.2010.29786

11. Katzmarzyk PT. Addressing obesity: implementing evidence-based lifestyle prevention and treatment strategies in clinical practice. Med Clin North Am. 2023;107(6):1025-1034. doi:10.1016/j.mcna.2023.06.011

12. Shaw M. Semaglutide enhances heart failure outcomes in obesity. The American Journal of Managed Care^®. August 30, 2024. Accessed September 1, 2024. https://www.ajmc.com/view/semaglutide-enhances-heart-failure-outcomes-in-obesity

14. Okunogbe A, Nugent R, Spencer, Powis J, Ralston J, Wilding J. BMJ Glob Health. 2022;7(9):e009773. doi:10.1136/bmjgh-2022-009773.