Measuring the content of cholesterol in skin tissue is a noninvasive way to assess the thickness of the carotid artery wall, which in turn is a validated measure of symptomless hardening-of-the-arteries, researchers report.

“A noninvasive assay to measure skin tissue cholesterol recently has become available for use in the outpatient setting as a cardiovascular risk prediction tool,” Dr. James H. Stein and colleagues from the University of Wisconsin Medical School, Madison, write in the American Heart Journal.

The skin test involves applying a special solution to a small area of the palm for one minute. The area is then blotted dry and an indicator solution applied, which turns blue. The hue depends on the cholesterol level, and can be accurately measured with a probe connected to a computer.

The researchers examined whether skin cholesterol content is related to the carotid artery wall thickness, after adjusting for cardiovascular risk factors, in 81 subjects (average age 56 years) who were free of known vascular disease. Along with measurement of skin cholesterol, the carotid arteries were assessed by ultrasound.

The subjects with the highest skin cholesterol level had significantly higher carotid wall thickness compared with those with the lowest skin cholesterol content, the researchers report.

Skin cholesterol remained significantly associated with carotid artery wall thickness after taking account of numerous other cardiovascular risk factors.

“Because skin tissue cholesterol is easy to measure,” Stein and colleagues conclude, “it may be a useful office-based tool for cardiovascular risk prediction.”

SOURCE: American Heart Journal, December 2005.