A recent investigation published in The Journal of the American Medical Association (JAMA) evaluated the prevalence and temporal patterns of metabolic syndrome among adults in the United States.
Metabolic syndrome is characterized by a combination of cardiometabolic risk factors and is linked to increased morbidity and mortality. Disruptions to daily routines and healthcare delivery during the COVID-19 pandemic may have influenced these risk factors, yet contemporary national estimates have been limited.
Study Design and Data Sources
The researchers analyzed trends in metabolic syndrome prevalence among U.S. adults from 2013 through August 2023 using data from the National Health and Nutrition Examination Survey (NHANES). The study included participants aged 20 years and older. Survey response rates declined substantially over time, from 68.5% in 2013–2014 to 25.7% in 2021–2023. To address this, analyses incorporated survey weights to adjust for nonresponse, and sensitivity analyses did not identify evidence of nonresponse bias.
Definition of Metabolic Syndrome
Metabolic syndrome was defined as the presence of at least three of the following criteria: elevated triglycerides, hypertension, impaired fasting glucose or diabetes treatment, increased waist circumference, or reduced high-density lipoprotein (HDL) cholesterol. Thresholds included triglycerides ≥150 mg/dL; blood pressure ≥130/85 mmHg or antihypertensive medication use; fasting glucose ≥100 mg/dL or diabetes treatment; waist circumference >88 cm in women or >102 cm in men; and HDL cholesterol <40 mg/dL in men or <50 mg/dL in women.
Race and ethnicity were self-reported. Age-standardized prevalence estimates were calculated using the 2020 U.S. Census population, and logistic regression models were used to assess temporal trends and subgroup differences.
Prevalence Estimates and Component Trends
The final analytic sample comprised 11,570 adults. The age-standardized prevalence of metabolic syndrome was 38.7%. Although prevalence increased modestly from 35.4% in 2013–2014 to 38.5% in 2021–2023, this change was not statistically significant.
Among individual components, hypertriglyceridemia showed a significant nonlinear pattern, decreasing through 2017–2020 before rising sharply in the most recent survey cycle. Other metabolic syndrome components fluctuated but did not demonstrate statistically significant trends.
Subgroup Analyses
A significant increase in metabolic syndrome prevalence was observed among adults aged 60 years and older, rising from 50.2% to 62.4% over the study period. No significant changes were detected among younger age groups or between sexes.
Racial and ethnic subgroup analyses revealed a significant increase among non-Hispanic Black adults. No consistent trends were observed across poverty income ratio categories or other demographic subgroups.
Interpretation and Public Health Implications
By 2023, nearly 40% of U.S. adults met criteria for metabolic syndrome. While overall prevalence remained relatively stable over the past decade, increases among older adults and non-Hispanic Black individuals highlight persistent health disparities. Rising hypertriglyceridemia may reflect obesity-related lipid abnormalities, dietary changes, or disruptions in healthcare during the COVID-19 pandemic.
Despite limitations related to declining response rates and the cross-sectional design, the findings underscore the importance of sustained prevention strategies and equitable access to cardiometabolic care.
