Decades of improving US cholesterol levels abruptly ended in 2008, study finds
The study, by researchers at Quest Diagnostics, examined blood-serum cholesterol test results of nearly 105 million adult Americans of both genders in all 50 states and the District of Columbia from 2001-2011.
"Our study suggests that significant improvements in heart disease risk through declines in LDL cholesterol blood levels over the past several decades came to an unexpected and sudden end in 2008," said investigator Robert Superko, MD, medical director, cardiovascular disease, Quest Diagnostics.
"The unprecedented scale of our data set should spur additional research to identify the cause or causes in order to prevent a possible reversal in years of gains in cardiovascular health in the US population."
Between 2001 and 2008, the average age-adjusted mean LDL levels declined from about 120 mg/dL to 104.7 mg/dL, but plateaued at that level for the remainder of the study period, he said.
The reason is not clear, but it is possible that the recession played a role in that patients may have been less inclined to visit their physician or use their medications at full dose from 2008 onwards, said Harvey W. Kaufman, M.D., senior medical director at Quest Diagnostics.
The investigators also theorized that statins users in the study may have reached the maximum therapeutic-threshold level.
LDL levels of 100 mg/dL or lower are considered optimal by the American Heart Association.
For more details of the study, "Blood Cholesterol Trends 2001-2011 in the United States: Analysis of 105 Million Patient Records," published online on May 10 in PLOS ONE, click here.
