Study Draws Attention to Poor Levels of Cardiometabolic Health in US Adults

Meghan O'Hearn, MS

New research from an analysis of trends in the cardiovascular health of US adults from 1999-2018 is drawing attention to concerning trends related to cardiometabolic health across the nation.

Using a nationally representative sample of about 55,000 adults aged 20 years and older from the 10 most recent cycles of the National Health and Nutrition Examination Survey (NHANES), investigators found just 75 of US adults had optimal levels of cardiometabolic health as of 2017-2018 and also shed light on other trends, including increased prevalence of diabetes or prediabetes and adiposity.

“These numbers are striking. It’s deeply problematic that in the United States, one of the wealthiest nations in the world, fewer than 1 in 15 adults have optimal cardiometabolic health,” said lead investigator Meghan O’Hearn, MS, a doctoral candidate at the Friedman School of Nutrition Science and Policy at Tufts University, in a statement. “We need a complete overhaul of our healthcare system, food system, and built environment, because this is a crisis for everyone, not just one segment of the population.”

Launched with the intent of investigating trends in cardiometabolic health among US adults, the current study was designed as an analysis of data from 55,081 adults who participated in NHANES cycles from 1999-2018. Investigators defined optimal cardiometabolic health based on assessments of adiposity, blood glucose, blood lipids, blood pressure, and absence of clinical cardiovascular disease events, with investigators assigning scores of optimal, intermediate, and poor assigned for each of the 5 components.

Optimal adiposity was defined as a BMI below 25 kg/m2 and a waist circumference of 88 cm or less in women and 102 cm or less in men. Optimal blood glucose was defined as a fasting plasma glucose less than 100 mg/dL and an HbA1c greater than 5.7% while not taking diabetes medication. Optimal blood lipids were defined as a total cholesterol to high-density lipoprotein ratio of less than 3.5:1 and not taking lipid-lowering medications. Optimal blood pressure was defined as a systolic blood press less than 120 mmHg and a diastolic blood pressure less than 80 mmHg without the presence of blood pressure-lowering medications. Optimal history of cardiovascular disease was defined as the absence of angina, coronary heart disease, myocardial infarction, heart failure, and stroke. As part of the study, investigators planned multiple subgroups analyses, including those stratified by age, sex, race/ethnicity, education level, and income.

When assessing sociodemographic trends from 1999-2018 within NHANES data, investigators found the proportion of duels aged older than 65 years increased from 15.8% in the 1999-2000 cycle to 20.4% in the 2017-2018 cycle. Conversely, the proportion of those aged 20-34 years declined from 31.8% in the 1999-2000 survey cycle to 27.6% in the 2017-2018 cycle. Investigators also pointed out the proportion of non-Hispanic White adults decreased from 70.3% to 62.2% from the 1999-2000 survey cycle to the 2017-2018 cycle while those identifying as Other races, which included Asians and those identifying as multiracial, increased from 4.4% to 10.5%.

Upon analysis, investigators found just 6.8% (95% CI, 5.4-8.1%) of US adults had optimal cardiometabolic health in the 2017-2018 survey cycle, with the mean number of optimal levels of the 5 factors decreasing from 2.5 (95% CI, 2.4-2.6) in the 1999-2000 survey cycle to 2.2 (95% CI, 2.1-2.3) in 2017-2018. In subgroup analyses, results incited optimal cardiometabolic health was less likely among adults aged older than 65 years (0.4% [95% CI, 0.0-1.0%]) compared to those aged 20-34 years (15.3% [95% CI, 11.6-19.1%]) and among men (3.1% [95% CI, 1.9-4.4%]) compared to women (10.4% [95% CI, 8.2-12.6%]).

When assessing changes in individual components of cardiometabolic health, the greatest declines were observed for adiposity (optimal levels: 33.8%-24.0%; poor levels: 47.7%-61.9%) and glucose (optimal levels: 59.4%-36.9%; poor levels: 8.6-13.7%) (P <.001 for each). In the 2017-2018 survey cycle, the prevalence of optimal cardiometabolic health was lower among US adults with lower (5.0% [95% CI, 2.8%-7.2%]) educational attainment compared to higher education attainment (10.3% [95% CI, 7.6-13.0%]) and among Mexican Americans (3.2% [95% CI, 1.4-4.9%]) compared to non-Hispanic White (8.4% [95% CI, 6.3-10.4%]) adults.

“This is really problematic. Social determinants of health such as food and nutrition security, social and community context, economic stability, and structural racism put individuals of different education levels, races, and ethnicities at an increased risk of health issues,” said senior investigator Dariush Mozaffarian, MD, DrPH, dean of the Friedman School, in the aforementioned statement. “This highlights the other important work going on across the Friedman School and Tufts University to better understand and address the underlying causes of poor nutrition and health disparities in the US and around the world.”

This study, “Trends and Disparities in Cardiometabolic Health Among U.S. Adults, 1999-2018,” was published in the Journal of the American College of Cardiology.