Average levels of total cholesterol, non-high-density lipoprotein cholesterol and low-density lipoprotein cholesterol all generally declined between 1988 and 2010, according to a study.
Margaret D. Carroll, MSPH, of the Centers for Disease Control and Prevention, and colleagues conducted a study to examine trends in serum lipids in adults between 1988 and 2010, using three distinct U.S. cross-sectional National Health and Nutrition Examination Surveys: 1988-1994 (16,573 participants), 1999-2002 (9,471 participants), and 2007-2010 (11,766 participants). Included in the analysis were measurements of average levels of total cholesterol, LDL-C, HDL-C, non-HDL-C and geometric triglyceride. The researchers also examined the prevalence of lipid-lowering medication use.
As reported in the Oct. 17 issue of JAMA, the authors found that average total cholesterol declined from 206 mg/dL in 1988-1994 to 203 mg/dL in 1999-2002 and 196 mg/dL in 2007-2010. Similar trends over this 22-year period were observed in age-adjusted average TC levels for men and for women.
From 1988 to 2010, researchers found a decreasing linear trend in age-adjusted average LDL-C levels for all adults, from 129 mg/dL in 1988-1994 to 123 mg/dL in 1999-2002 and 116 mg/dL in 2007-2010. The researchers noted that while men had a higher age-adjusted average LDL-C level than women during 1988-94 and 1999-2002, there no longer was a sex difference during 2007-10.
The researchers observed an increasing linear trend in age-adjusted average HDL-C from 1988-94 to 2007-10 (50.7 mg/dl vs. 52.5 mg/dL). Between 1988 and 2010, a linear decline in age-adjusted average non-HDL-C level was observed for all adults.
The age-adjusted geometric average triglyceride level for all adults increased from 118 mg/dL in 1988-1994 to 123 mg/dL in 1999-2002, then declined in 2007-2010 to 110 mg/dL.
The researchers also found that from 1988 to 2010, there was an increasing trend in the age-adjusted percentage of adults taking lipid-lowering medications (from 3.4% in 1988-1994 to 9.3% in 1999-2002 and 15.5% in 2007-2010). Among men and women ages 50 and older, increases of up to 35% in use of lipid-lowering medications were observed.
Even among adults not receiving lipid-lowering medications, the general trends in lipids were similar to those reported for adults overall, the researchers wrote. Among obese adults, average total cholesterol, non-HDL-C, LDL-C and geometric average triglycerides declined between 1988 and 2010.
"The favorable trends in TC [total cholesterol], non HDL-C and LDL-C may be due in part to a decrease in consumption of trans-fatty acids or other healthy lifestyle changes, in addition to an increase in the percentage of adults taking lipid-lowering medications," the authors wrote. "They are unlikely to be the result of changes in physical activity, obesity or intake of saturated fat."
That’s because the intake of saturated fat as a percentage of calories did not decrease between 1999 and 2008; little progress was made from 1998 to 2008 in increasing leisure-time physical activity levels of adults; and the prevalence of obesity among adults remains high, at more than a third of the population, according to information cited in the study.
The study abstract is available at http://jama.jamanetwork.com/article.aspx?articleid=1383233.
Margaret D. Carroll, MSPH, of the Centers for Disease Control and Prevention, and colleagues conducted a study to examine trends in serum lipids in adults between 1988 and 2010, using three distinct U.S. cross-sectional National Health and Nutrition Examination Surveys: 1988-1994 (16,573 participants), 1999-2002 (9,471 participants), and 2007-2010 (11,766 participants). Included in the analysis were measurements of average levels of total cholesterol, LDL-C, HDL-C, non-HDL-C and geometric triglyceride. The researchers also examined the prevalence of lipid-lowering medication use.
As reported in the Oct. 17 issue of JAMA, the authors found that average total cholesterol declined from 206 mg/dL in 1988-1994 to 203 mg/dL in 1999-2002 and 196 mg/dL in 2007-2010. Similar trends over this 22-year period were observed in age-adjusted average TC levels for men and for women.
From 1988 to 2010, researchers found a decreasing linear trend in age-adjusted average LDL-C levels for all adults, from 129 mg/dL in 1988-1994 to 123 mg/dL in 1999-2002 and 116 mg/dL in 2007-2010. The researchers noted that while men had a higher age-adjusted average LDL-C level than women during 1988-94 and 1999-2002, there no longer was a sex difference during 2007-10.
The researchers observed an increasing linear trend in age-adjusted average HDL-C from 1988-94 to 2007-10 (50.7 mg/dl vs. 52.5 mg/dL). Between 1988 and 2010, a linear decline in age-adjusted average non-HDL-C level was observed for all adults.
The age-adjusted geometric average triglyceride level for all adults increased from 118 mg/dL in 1988-1994 to 123 mg/dL in 1999-2002, then declined in 2007-2010 to 110 mg/dL.
The researchers also found that from 1988 to 2010, there was an increasing trend in the age-adjusted percentage of adults taking lipid-lowering medications (from 3.4% in 1988-1994 to 9.3% in 1999-2002 and 15.5% in 2007-2010). Among men and women ages 50 and older, increases of up to 35% in use of lipid-lowering medications were observed.
Even among adults not receiving lipid-lowering medications, the general trends in lipids were similar to those reported for adults overall, the researchers wrote. Among obese adults, average total cholesterol, non-HDL-C, LDL-C and geometric average triglycerides declined between 1988 and 2010.
"The favorable trends in TC [total cholesterol], non HDL-C and LDL-C may be due in part to a decrease in consumption of trans-fatty acids or other healthy lifestyle changes, in addition to an increase in the percentage of adults taking lipid-lowering medications," the authors wrote. "They are unlikely to be the result of changes in physical activity, obesity or intake of saturated fat."
That’s because the intake of saturated fat as a percentage of calories did not decrease between 1999 and 2008; little progress was made from 1998 to 2008 in increasing leisure-time physical activity levels of adults; and the prevalence of obesity among adults remains high, at more than a third of the population, according to information cited in the study.
The study abstract is available at http://jama.jamanetwork.com/article.aspx?articleid=1383233.
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