Prevalence of the metabolic syndrome between 1999 and 2014 in the United States adult population and the impact of the 2007-2008 recession: an NHANES study.

To document changes in prevalence of the metabolic syndrome (MetS) in the United States adult population between 1999 and 2014 and to explore how variations in the dietary intakes explain changes in MetS prevalence and its components over time. A total of 38 541 individuals (aged 20-85 years; National Health and Nutrition Examination Survey 1999-2014) were studied. Outcome variables were MetS, waist circumference (WC), plasma high-density lipoprotein cholesterol (HDL-c), triglycerides, fasting glucose (FG) levels, resting systolic and diastolic blood pressure, dietary intakes (total daily energy, carbohydrates, proteins, fats, sodium, and alcohol intakes), the poverty income ratio (PIR) and sociodemographic data (age, sex, ethnicity). Overall, the prevalence of the MetS significantly increased between 1999 and 2014 (27.9% to 31.5%). High plasma FG levels and high WC increased between 1999 and 2014, while the prevalence of the other components of MetS decreased or remained stable. Interestingly, a significant peak in MetS prevalence was observed in 2007-2008 compared with 1999-2006 (34.4% vs 27.6%), accompanied by a concomitant increase in WC and plasma FG levels, as well as a decrease in plasma HDL-c. Finally, significant decreases were observed for the PIR, total daily energy intake, sodium, and all macronutrient intakes in 2007-2008 compared with 1999-2006 (all < 0.01). Results showed that the MetS prevalence significantly increased between 1999 and 2014 in the United States adult population, with a peak in 2007-2008. Interestingly, the 2007-2008 peak in MetS prevalence was accompanied by decreases in the PIR, total daily energy, and macronutrients intakes, suggesting potential impact of the 2007-2008 recession.