Cardiovascular Risk Factors Persist with Demographic Differences

Jiang He, MD

A recent study estimated 20-year trends in multiple cardiovascular risk factors in the US population in order to compare trends in race and ethnicity and socioeconomic status using data from the National Health and Nutrition Examination Surveys (NHANES) from 1999 - 2018.

Led by Jiang He, MD, Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, investigators observed differences in cardiovascular risk factors continued between Black participants and White participants, noting the difference may have to do with the social determinants of health.

Methods

The NHANES assessed the health and nutritional status of the US general population. Investigators used a stratified, multistage probability sampling method to select a series of cross-sectional, nationally representative samples. A total of 10 cycles conducted from 1999 - 2000 through 2017 - 2018 were used in the analysis.

During each 2-year survey, patients completed an in-home interview and a mobile examination center visit. A questionnaire collected information on age, race and ethnicity, sex, education, income, and medical history.

Additionally, data on education, income, employment, housing, health insurance, and access to health care was gathered by investigators.

A physical examination measured weight, height, and calculated body mass index. Further, 3 blood pressure measurements were obtained and used in analyses, determining total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein (LDL) cholesterol, and hemoglobin A1c.

What did they find?

In the study, the mean age of participants ranged from 49.0 - 51.8 years, with the proportion of women from 48.2% to 51.3% in surveys.

Data show proportions of patients with less than a high school education decreased from 39.7% in 1999 - 2000 to 20.0% in 2017-2018, while patients who were college graduates or higher increased from 15.4% - 24.0%.

Investigators observed age- and sex-adjusted mean body mass index increased from 28.0 (95% CI, 27.5 - 28.5) to 29.8 (95% CI, 29.2 - 30.4), while mean hemoglobin A1c increased from 5.4% (95% CI, 5.3% - 5.5%) to 5.7% (95% CI, 5.6% - 5.7%), all P <.001.

Further, the mean systolic blood pressure decreased from 123.5 mm Hg (95% CI, 122.2 - 124.8 mm Hg) in 1999-2000 to 120.5 mm Hg (95% CI, 119.6 - 121.3 mm Hg) in 2009-2010. It then increased to 122.8 mm Hg (95% CI, 121.7 - 123.8 mm Hg), all P <.001.

The primary investigators saw age-and sex-adjusted body mass index, systolic blood pressure, and hemoglobin A1c showed consistently higher numbers, in comparison to lower total cholesterol in non-Hispanic Black patients compared with non-Hispanic White patients (all P <.001).

In addition, the mean age- and sex-adjusted 10-year risk of atherosclerotic cardiovascular disease showed a significantly higher rate in non-Hispanic Black participants compared to non-Hispanic White participants.

They noted a difference of 1.4% (95% CI, 1.0% - 1.7%) in 1999 - 2008 and 2.0% (95% CI, 1.7 - 2.4%) in 2009 - 2018.

Following adjustments for education, income, home ownership, employment, health insurance, and access to healthcare, the difference was lessened at -0.3% (95% CI, -0.6% to 0.1%) in 1999-2008 and 0.7% (95% CI, 0.3% - 1.0%) in 2009 - 2018.

Are there any takeaways?

Although CVD mortality and risk have decreased significantly since 1950, the team concluded Black patients still have higher risk in comparison to patients in other racial and ethnic groups.

“To our knowledge, this is the first study to report that body mass index, systolic blood pressure, and hemoglobin A1c were persistently higher in the Black population compared with the White population after adjustment for important social determinants of health, such as education, income, housing, employment, health insurance, and access to health care,” investigators wrote.

The study, “Trends in Cardiovascular Risk Factors in US Adults by Race and Ethnicity and Socioeconomic Status, 1999-2018,” was published in JAMA.