Trends in serum lipids among US youths aged 6 to 19 years, 1988-2010

Abstract

Context: For more than 20 years, primary prevention of coronary heart disease has included strategies intended to improve overall serum lipid concentrations among youths.

Objective: To examine trends in lipid concentrations among youths from 1988-1994 through 2007-2010.

Design, setting, and participants: Cross-sectional analysis of serum lipid concentrations among 16,116 youths aged 6 to 19 years who participated in the nationally representative National Health and Nutrition Examination Survey during 3 time periods: 1988-1994, 1999-2002, and 2007-2010.

Main outcome measures: Among all youths, mean serum total cholesterol (TC), non-high-density lipoprotein cholesterol (non-HDL-C), high-density lipoprotein cholesterol (HDL-C); and among adolescents only, low-density lipoprotein cholesterol (LDL-C) and geometric mean triglyceride levels. Trends in adverse lipid concentrations are reported for TC levels of 200 mg/dL and greater, non-HDL-C levels of 145 mg/dL and greater, HDL-C levels of less than 40 mg/dL, LDL-C levels of 130 mg/dL and greater, and triglyceride levels of 130 mg/dL and greater.

Results: Among youths aged 6 to 19 years between 1988-1994 and 2007-2010, there was a decrease in mean TC (from 165 mg/dL [95% CI, 164-167] to 160 mg/dL [95% CI, 158-161]; P < .001) and a decrease in the prevalence of elevated TC (from 11.3% [95% CI, 9.8%-12.7%] to 8.1% [95% CI, 6.7%-9.5%]; P = .002). Mean HDL-C significantly increased between 1988-1994 and 2007-2010, but the prevalence of low HDL-C did not change. Mean non-HDL-C and prevalence of elevated non-HDL-C both significantly decreased over the study period. In 2007-2010, 22% (95% CI, 20.3%-23.6%) of youths had either a low HDL-C level or high non-HDL-C, which was lower than the 27.2% (95% CI, 24.6%-29.7%) in 1988-1994 (P = .001). Among adolescents (aged 12-19 years) between 1988-1994 and 2007-2010, there was a decrease in mean LDL-C (from 95 mg/dL [95% CI, 92-98] to 90 mg/dL [95% CI, 88-91]; P = .003) and a decrease in geometric mean triglycerides (from 82 mg/dL [95% CI, 78-86] to 73 mg/dL [95% CI, 70-76]; P < .001). Prevalence of elevated LDL-C and triglycerides between 1988-1994 and 2007-2010 also significantly decreased.

Conclusions: Between 1988-1994 and 2007-2010, a favorable trend in serum lipid concentrations was observed among youths in the United States but almost 1 in 10 had elevated TC in 2007-2010.

Figure.

Prevalence of Adverse Lipid Concentrations Over Time Among US Children and Adolescents, 1988–2010 Adverse lipid concentrations: total cholesterol (TC, ≥200 mg/dL), high-density lipoprotein (HDL) cholesterol (<40 mg/dL), non-HDL cholesterol (≥145 mg/dL), low-density lipoprotein (LDL) cholesterol (≥130 mg/dL), and triglycerides (≥130 mg/dL). All comparisons, except HDL, show a significant linear trend between 1988–1994 and 2007–2010 (P<.05). Comparisons for TC, HDL, non-HDL, and either HDL or non-HDL are among youths aged 6 to 19 years; LDL and triglyceride comparisons are among youths aged 12 to 19 years. Sample sizes: for TC, HDL, non-HDL, and either HDL or non-HDL, 5759 in 1988–1994, 6152 in 1999–2002, and 4205 in 2007–2010; for LDL, 1093 in 1988–1994, 1853 in 1999–2002, and 995 in 2007–2010; and for triglycerides, 1106 in 1988–1994, 1861 in 1999–2002, and 996 in 2007–2010. Error bars indicate 95% CIs. Data are from National Health and Nutrition Examination Surveys.^,,