Expert addresses global burden of obesity, CVD

DALLAS — Access to health care and prevention methods is critical to reducing cardiovascular disease-related mortality; flexible solutions are needed to overcome the worldwide burden of obesity, according to Karen L. Herbst, PhD, MD.

“Worldwide, overweight and obesity cause more deaths than underweight, and 65% of the world population live in countries where overweight and obesity kill more people than underweight,” Herbst, an associate professor at the University of Arizona in Tucson, said during a presentation at AHA 2013.

Global, economic burden of CVD

Herbst cited the Global Burden of Disease Study of 2010, which was a large systematic effort to describe the global distribution and causes of a wide array of major diseases, injuries and health risk factors.

“Since 1970, men and women worldwide have gained slightly more than 10 years of life expectancy overall, but they spend more years living with injury and illness,” she said.

In 2008, more than 17 million people (>0.25% of the world population) died of CVD, according to Herbst. More than 80% of those deaths occurred in low- and middle-income countries.

This global burden could be due to behavioral risk factors, such as physical inactivity, tobacco usage and unhealthy diets, she said.

From 2011 to 2025, the projected cumulative economic losses from all non-communicable diseases (ie, cancer, respiratory diseases, diabetes and CVD) are $7.28 trillion in low- and middle-income countries, according to a report by the American College of Cardiology presented by Herbst.

“There is no end in sight for direct medical costs for care of CVD,” she said. “If you just look at China alone, the annual direct costs are estimated at over $40 billion.”

Obesity by the numbers

Herbst cited a systematic analysis of epidemiological studies from 199 countries, in which 1.46 billion adults worldwide were estimated to be overweight in 2008. Of these, 502 million were obese.

“Think about this: More than 40 million children under the age of 5 were overweight in 2011,” Herbst said. “Until 1980, less than 1 in 10 people were obese; rates have doubled or tripled.”

In 19 of 34 countries, the majority of the population is now overweight or obese, according to Herbst. Increased BMI is a major risk factor for heart disease, stroke, type 2 diabetes and other chronic disease, she added.

“Severely obese people die 8 to 10 years sooner than those of normal weight; similar to smokers, with every 15 extra kilograms increasing the risk of early death by approximately 30%,” Herbst said. “Obesity is estimated to be responsible for 1% to 3% of total health expenditure in most countries (5% to 10% in the United States).”

The metrics of CVD

Coronary artery disease is not as obvious as obesity, Herbst said. Yet, disability-adjusted life years (DALYs) have shown that CVD is responsible for 10% of healthy years lost in low- and middle-income countries, and 18% in high-income countries.

In 1990, ischemic heart disease ranked fourth in health years lost, and it is now ranked first; stroke was ranked fifth, and is now ranked third, she said.

“Ischemic heart disease has increased by 29% and stroke by 19% over those 2 decades. If this continues, [by 2030] there will be almost 12 million stroke deaths, 70 million stroke survivors and more than 200 million DALYs lost globally,” Herbst said.

Corroborative evidence from PURE

Herbst said researchers in the Prospective Urban and Rural Epidemiological (PURE) study enrolled 155,245 patients from 17 countries to assess the influence of CV risk factors on CVD and mortality.

The study population included 16,110 patients from high-income countries; 104,260 patients from 10 middle-income countries; 34,875 patients from four low-income countries, according to data presented by Herbst.

Researchers found that CVD risk factors, but also treatment and preventive measures, were highest in the high-income countries and lowest in the low-income countries (P<.0001).

Hospitalizations for CVD also were highest in the high-income countries (P<.05). Fatal and other major CVD (myocardial infarction, stroke and heart failure) were less common in high-income countries, and non-major CVD was more common (P<.001 for all).

Major CVD occurred at a higher rate of 4.3 events per 1,000 person-years in high-income countries vs. 5.1 events in middle-income countries, and 6.4 events in low-income countries, according to data. Fatal CVD occurred at a rate of 0.6 events per 1,000 person-years in high-income countries vs. 1.7 events in middle-income and 3.8 in low-income countries.

“While risk factors for CVD are largely the same throughout the world, people in low-income countries are seven times more likely to die of CV events than those in high-income countries,” Herbst said.

‘It could be worse’

The challenge is to identify key aspects of health care that are effective and apply them to low-income and middle-income countries in a much more frugal matter, Herbst said.

“The good news is that it could be worse, as overweight rates may be stabilizing; the bad news is the rate of diabetes continues to rise,” she said.

Ultimately, flexible solutions and access to prevention and health care are vital strategies for decreasing CVD death and overcoming obesity globally, Herbst said. – by Samantha Costa

For more information:

Herbst KL. Sunday Morning Program #704: Obesity in CVD. Confluence of obesity and CVD: global health burden. Presented at: the American Heart Association Scientific Sessions; Nov. 16-20, 2013; Dallas.

Disclosure: Herbst reports financial ties with Aspire Bariatrics and Pathway Genomics Inc.